- Email: [email protected]
Prognostic value of KRAS mutations in stage III colon cancer: post hoc analysis of the PETACC8 phase III trial dataset
original articles
19. Gilardini Montani MS, Prodosmo A, Stagni V et al. ATM-depletion in breast cancer cells confers sensitivity to PARP inhibition. J Exp Clin Cancer Res 2013; 32: 95. 20. Min A, Im SA, Yoon YK et al. RAD51C-deficient cancer cells are highly sensitive to the PARP inhibitor olaparib. Mol Cancer Ther. 2013; 12: 865–877. 21. Koppensteiner R, Samartzis EP, Noske A et al. Effect of MRE11 loss on PARP-inhibitor sensitivity in endometrial cancer in vitro. PLoS One 2014; 9: e100041. 22. Ibragimova I, Cairns P. Assays for hypermethylation of the BRCA1 gene promoter in tumor cells to predict sensitivity to PARP-inhibitor therapy. Methods Mol Biol 2011; 780: 277–291. 23. Drew Y, Mulligan EA, Vong WT et al. Therapeutic potential of poly(ADP-ribose) polymerase inhibitor AG014699 in human cancers with mutated or methylated BRCA1 or BRCA2. J Natl Cancer Inst 2011; 103(4): 334–346.
Annals of Oncology 25: 2378–2385, 2014 doi:10.1093/annonc/mdu464 Published online 6 October 2014
Prognostic value of KRAS mutations in stage III colon cancer: post hoc analysis of the PETACC8 phase III trial dataset H. Blons1,2,3, †, J. F. Emile4,5,†, K. Le Malicot6, †, C. Julié4, A. Zaanan7, J. Tabernero8, E. Mini9, G. Folprecht10, J. L. Van Laethem11, J. Thaler12, J. Bridgewater13, L. Nørgård-Petersen14, E. Van Cutsem15, C. Lepage16, M. A. Zawadi17, R. Salazar18, P. Laurent-Puig1,2,3,† & J. Taieb7,2, †* 1 UMR-S1147, INSERM, Paris; 2Paris Descartes University, Paris; 3APHP Department of Biology, Georges Pompidou Hospital, Paris; 4Department of Pathology, APHP Ambroise Paré Hospital, Boulogne-Billancourt; 5Paris-Ouest University, Versailles Saint-Quentin; 6Department of Statistics, Fédération Francophone de Cancérologie Digestive, Dijon; 7APHP Department of Hepatogastroenterology and GI Oncology, Georges Pompidou Hospital, Paris, France; 8Department of Medical Oncology, Vall d‘Hebron University Hospital and Institute of Oncology (VHIO), Barcelona, Spain; 9Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy; 10 1st Medical Department, University Hospital Carl Gustav Carus, Dresden, Germany; 11Deptartment of Gastroenterology, Erasme University Hospital, Brussels, Belgium; 12 Department of Internal Medicine IV, Klinikum Wels-Grieskirchen, Wels, Austria; 13UCL Cancer Institute, University College London, London, UK; 14Department of Oncology, Rigshospitalet, København, Denmark; 15Department of Digestive Oncology, University Hospitals and KULeuven, Leuven, Belgium; 16Department of Hepato-Gastroenterology, Dijon University Hospital and INSERM U 866, Dijon; 17GI Oncology, Les Oudairies Hospital, La Roche sur Yon, France; 18Catalan Institute of Oncology (IDIBELL), Barcelona, Spain
Received 10 July 2014; revised 18 September 2014; accepted 18 September 2014
Background: The prognostic value of KRAS mutations in colon adenocarcinoma is controversial. We examined this question as an ancillary study of the PETACC8 phase III trial. Patients and methods: We analyzed the pronostic impact of KRAS exon 2 mutations in stage III colon cancer patients (n = 1657) receiving adjuvant FOLFOX ± cetuximab therapy included in the PETACC8 trial. Patients with BRAF-mutated cancers were excluded and, as no difference was found for time to recurrence (TTR) and disease-free survival (DFS) between treatment arms, both were pooled for analysis. Associations with TTR and DFS were analyzed using a Cox proportional hazards model. Results: KRAS mutations were found in 638 of 1657 tumors and linked to shorter TTR (P < 0.001). However, when specific mutations were compared with wild-type, codon 12 mutations [hazard ratio (HR) 1.67, 95% confidence interval (CI) 1.35–2.04; P < 0.001] but not codon 13 (HR 1.23, 95% CI 0.85–1.79; P = 0.26) were significantly associated with shorter *Correspondence to: Dr Julien Taieb, Georges Pompidou Hospital, Department of Hepatogastroenterology and GI Oncology, Université Paris Descartes, 20 rue Leblanc, 75015 Paris, France. Tel: +33-1-5609351; Fax: +33-1-56093441; E-mail: julien.taieb@ egp.aphp.fr †
These authors contributed equally.
© The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: [email protected].
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15. Vaz FH, Machado PM, Brandao RD et al. Familial breast/ovarian cancer and BRCA1/2 genetic screening: the role of immunohistochemistry as an additional method in the selection of patients. J Histochem Cytochem 2007; 55(11): 1105–1113. 16. Carser JE, Quinn JE, Michie CO et al. BRCA1 is both a prognostic and predictive biomarker of response to chemotherapy in sporadic epithelial ovarian cancer. Gynecol Oncol 2011; 123(3): 492–498. 17. Radosa MP, Hafner N, Camara O et al. Loss of BRCA1 protein expression as indicator of the BRCAness phenotype is associated with favorable overall survival after complete resection of sporadic ovarian cancer. Int J Gynecol Cancer 2011; 21(8): 1399–1406. 18. Weberpals JI, Tu D, Squire JA et al. Breast cancer 1 (BRCA1) protein expression as a prognostic marker in sporadic epithelial ovarian carcinoma: an NCIC CTG OV.16 correlative study. Ann Oncol 2011; 22(11): 2403–2410.
Annals of Oncology
original articles
Annals of Oncology
TTR, independently of other covariates. The interaction test showed that, regarding tumor location (distal versus proximal), KRAS genotype affects differently on recurrence (P = 0.02) and DFS (P = 0.042). Subgroup analysis showed that KRAS only affected TTR and DFS in distal tumors (n = 1043; 692 wild type; 351 mutated), with an increased risk of relapse (HR 1.96, 95% CI 1.51–2.56; P < 0.0001) for KRAS codon 12 mutations and a borderline significance for codon 13 mutations (HR 1.59, 95% CI 1.00–2.56; P = 0.051). Conclusion: KRAS exon 2 mutations are independent predictors of shorter TTR in patients with resected stage III distal colon cancers receiving adjuvant therapy. Future clinical trials in the adjuvant setting should consider both the tumor location and KRAS mutations as important stratification factors. Clinical trial number: This is an ancillary study of the PETACC8 trial: EUDRACT 2005-003463-23. Key words: colorectal cancer, KRAS mutation, cetuximab, proximal colon, distal colon, prognosis
Colorectal cancer (CRC) is the fourth cause of cancer death worldwide [1, 2]. Despite advances in drug therapy and the use of targeted treatments [3, 4], many patients with completely resected cancers still die of metastatic relapses, reflecting a biological heterogeneity, which is not fully understood. CRC occurs through a multistep process driven by the accumulation of genetic alterations, of which KRAS activating mutations are considered one of the earliest [5]. They are present in ∼45% of CRCs and exclusive of other genetic alterations in EGFR pathway activators such as BRAF and NRAS. KRAS mutations at codons 12 and 13 are the most frequent alterations in CRC, representing more than 90% of all mutations [6]. KRAS status was shown to be a predictive marker of resistance to EGFR inhibitors, leading to restricted use of these drugs in patients with KRAS wild-type metastatic CRC [7–9]. In contrast, the influence of KRAS mutations on outcome is less evident. In resected colon cancer patients, KRAS mutational status has been linked to disease recurrence and poorer overall survival in recent large prospective cohorts and clinical trials but discrepancies remain [10–12]. In BRAF wild-type CRC, a poor prognosis was either related to KRAS mutations or restricted to patients with codon 12 mutated tumors [11, 13–15]. This post hoc study of the PETACC8 [16] phase III trial analyzed the impact of individual KRAS mutations on time to recurrence (TTR) and disease-free survival (DFS) in stage III CRC patients undergoing surgery and standard 5-fluorouracil (5-FU) and oxaliplatin-based adjuvant therapy and refined the results according to tumor location.
materials and methods patient characteristics Patients from the PETACC8 trial had completely resected, histologically proven stage III colon adenocarcinoma and were randomized to receive, as adjuvant treatment, either 6 months of FOLFOX 4 or FOLFOX 4-cetuximab [16]. The trial started in December 2005, it was amended in June 2008 to enroll patients with KRAS wild-type tumors. Written informed consent was required for patients’ participation to the PETACC8 planned translational program.
DNA extraction and mutation analysis Tumor DNAs were extracted from formalin-fixed and paraffin-embedded (FFPE) tissues using the QIAamp® DNA Mini Kit (Qiagen®). Molecular analysis was centralized and carried out retrospectively for 2096 patients
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included before trial amendment, and prospectively for the other 463 patients, by real-time PCR using TaqMan® probes (Applied Biosystems) for KRAS (c.34G > A/p.G12S, c.34G > C/p.G12R, c.34G > T/p.G12C, c.35G > A/ p.G12D, c.35G > C/p.G12A, c.35G > T/p.G12V and c.38G > A p.G13D) and BRAF (c.1799T > A/p.V600E). Each assay was validated to detect 10% of mutated alleles [17].
statistical analysis Patients were divided into two groups: group 1 with mutant KRAS/BRAF and group 2 with wild-type KRAS/BRAF. Comparisons of patients with specific mutations versus the wild-type population only concerned mutations representing more than 10% of all mutations detected this study. The end points for these analyses were TTR and DFS. TTR was defined as the time between the date of randomization and the date of local or metastatic recurrence. DFS was defined as the time between the date of randomization and the date of local or metastatic recurrence, second colon cancer or death, whichever occurred first. Overall survival data are not yet available for the PETACC8 trial and were thus not reported in this work. For comparisons of baseline characteristics, categorical outcomes were analyzed with χ 2 tests and continuous outcomes were compared with standard parametric or nonparametric tests. Continuous variables are presented as the mean (SD) and median interquartile range. TTR and DFS curves were estimated with the Kaplan–Meier method. Differences between groups of patients were analyzed using unstratified logrank tests. An unstratified Cox regression model was used to estimate hazard ratios (HRs), 95% confidence intervals (CIs) and P values for candidate prognostic factors. Factors included in the multivariate analyses were the treatment group, baseline variables imbalanced between the two PETACC8 arms, and prognostic factors identified in univariate analyses. The WHO 6th edition criteria were used for tumor staging. Analyses were carried out according to the intention-to-treat principle with a two-sided significance level of 5%. Results were unadjusted for multiple comparisons. All statistical analyses were done with the SAS statistical software package (version 9.4).
results study population Among the 2559 patients included in the PETACC8 phase III study, 1810 met all the criteria for molecular analysis (informed consent and available FFPE sample, no technical failure for KRAS/BRAF status determination), 153 were BRAF-mutated and excluded because of the prognostic impact of BRAF mutations (Figure 1), 1 tumor was KRAS- and BRAF-mutated and was also excluded of the analysis. Demographic and clinical characteristics of the patients in the KRAS molecular study (n =
doi:10.1093/annonc/mdu464 |
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introduction
original articles
Annals of Oncology
PETACC8 population n = 2559
KRAS not determined - No informed consent - Black not received - Insufficient material - Technical failure n = 624 (excluded)
KRAS Mut n = 638
KRAS WT n = 1297
BRAF not determined
- Insufficient material - Technical failure n = 125 (excluded) KRAS WT tested for BRAF n = 1172
KRAS WT/BRAD WT n = 1019
KRAS WT/BRAF Mut n = 153 (excluded)
Figure 1. Flow chart of PETACC8 trial molecular study evaluating the impact of KRAS mutations on time to recurrence and DFS in the BRAF wild-type sample population.
A
WT 8%
G12A
8%
Time to recurrence
0%
B
G12C
2%
G12D
13%
G12S
62%
G12R
4%
G12V
3%
G13D
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
P < 0.001 Mutated Wild-type 0
Wild-type 1019 Mutated 638
D
C
Time to recurrence
Codon 12 p.G12A p.G12C p.G12D p.G12S p.G12R p.G12V Codon 13
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
2
3 4 5
2
3
4
5
6
7 Years
933 547
693 465
501 394
182 150
5 5
0 0
0 0
P = 0.26 P < 0.001
Wild-type Codon 12 Codon 13 0
1
1
Wild-type 1019 Codon 12 502 Codon 13 136
1
2
3
4
5
6
7 Years
933 425 122
693 357 108
501 307 87
182 117 33
5 4 1
0 0 0
0 0 0
Figure 2. Time to recurrence according to KRAS status. (A) KRAS mutation types in the PETACC8 trial population. (B) In the entire population, KRAS status is related to shorter time to recurrence (P < 0.01). (C) Subsequent analysis showed that codon 12 (P < 0.01) but not codon 13 (P = 0.26) are associated with shorter time to recurrence. (D) Impact of individual alterations on time to recurrence, results or not statistically relevant for p.G12S and p.G12R due to the small number of tumors in these groups.
| Blons et al.
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- No translational research informed consent
original articles
Annals of Oncology
Table 1. Analyzed population—demographic and clinical characteristics Mutated (N = 638)
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P value
638 316 (38.1%) 322 (38.9%)
1019 513 (61.9%) 506 (61.1%)
χ 2: 0.7472
638 350 (36.5%) 288 (41.3%)
1019 610 (63.5%) 409 (58.61%)
χ 2: 0.0447
638 59.85 (9.42) 61.00 54.00; 67.00 23.00; 74.00
1019 58.79 (9.77) 60.00 53.00; 66.00 19.00; 75.00
W: 0.0301
638 562 (38.0%) 76 (42.9%) 0 (0.0)
1019 918 (62.0%) 101 (57.1%) 0 (0.0)
χ 2: 0.1995
613 503 (32.2%) 108 (38.8%) 2 (40%) 0 (0.0)
988 814 (61.8%) 170 (61.2%) 3 (60%) 1 (100%)
χ 2: 0.8805
634 351 (33.7%) 270 (46.1%) 13 (65%)
1015 692 (66.3%) 316 (53.9%) 7 (35%)
χ 2: <0.0001
630 131 (37.5%) 393 (39.1%) 103 (37.6%) 3 (33.3%)
1007 218 (62.5%) 612 (60.9%) 171 (62.4%) 6 (66.7%)
χ 2: 0.921
638 407 (38.7%) 231 (38.1%)
1019 644 (61.3%) 375 (61.9%)
χ 2: 0.8070
638 14 (30.4%) 37 (31.1%) 440 (38.5%) 147 (42.4%) 0 (0.0)
1019 32 (69.6%) 82 (68.9%) 703 (61.5%) 200 (57.6%) 2 (100%)
χ 2: 0.1135
638 134 (42.5%) 504 (37.6%)
1019 181 (57.5%) 838 (62.4%)
χ 2: 0.1019
638 323 (35.3%) 210 (42.4%) 105 (42.7%)
1019 593 (64.7%) 285 (57.6%) 141 (57.3%)
χ 2: 0.0106
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Treatment group n Folfox Folfox + Cetux Gender n Male Female Age n Moy. (SD) Median Q1; Q3 Min; max Age (Class) n Age ≤70 years Age >70 years Missing WHO performance status n 0 1 2 3 Tumor location n Distal colon Proximal colon Both sides Histopathology grading n Well differentiated Moderately differentiated Poorly differentiated Undifferentiated Pn classification n pN1 pN2 PT classification n pT1 pT2 pT3 pT4 pTx Bowel obstruction and perforation n Bowel obstruction and/or perforation No bowel obstruction and no perforation VELI n Vascular invasion or lymphatic infiltration No vascular invasion and no lymphatic infiltration Unknown
Wild-type (N = 1019)
original articles
Annals of Oncology
Table 2. Multivariate analysis and time to recurrence (TTR) N = 1629
Confidence interval (95%)
P-value
1.03
0.84
1.25
0.812
1.58
1.28
1.94
<0.0001
0.95
0.77
1.17
0.634
0.94
0.68
1.31
0.73
1.37
1.07
1.76
0.012
0.86
0.69
1.07
0.164
0.81 1.95 3.82
0.25 0.72 1.40
2.63 5.26 10.4
2.24
1.82
2.77
<0.0001
0.84
0.66
1.07
0.165
0.97
0.76
1.24
0.804
0.722 0.189 0.009
Bold values are to underline significance in the results.
1657) were not significantly different from those of the excluded population (supplementary data S1, available at Annals of Oncology online).
KRAS results Of the 1657 tumors, 38.5% had a KRAS mutation, located on codon 12 in 79% of the cases. Detailed repartition is shown on Figure 2A. KRAS mutations were more frequent in women, in proximal CRC, and were associated with age, and no vascular or lymphatic infiltration (Table 1).
outcome predictors In the PETACC8 trial, KRAS-mutated tumors were equally numerous in both treatment arms. Moreover, an interaction test was carried out between KRAS status (WT, codon 12 and codon13) and treatment (TTR P = 0.37; DFS P = 0.32) leading to the conclusion that both arms could be pooled to study the impact of KRAS mutations on TTR and DFS. Median follow-up was 3.4 years (95% CI 3.3–3.4) and 3.8 years (95% CI 3.8–3.9) for patients with wild-type and mutated tumors, respectively.
| Blons et al.
subgroup analysis We looked for a different impact of KRAS mutations on TTR and DFS between men and women. The results showed that KRAS codon 12 alterations were related to shorter TTR in both women and men (respectively, HR 1.78, 95% CI 1.29–2.46; P = 0.0004 and HR 1.58, 95% CI 1.19–2.09; P = 0.001). In proximal cancer, KRAS mutations were more frequent than in distal cancer, with a higher proportion of p.G13D and p. G12D alterations (Figure 3A) but had no impact on TTR (HR 1.29, 95% CI 0.90–1.84; NS; HR 0.89; 95% CI 0.50–1.59; NS) (Figure 3B). At the opposite, codon 12 alterations (HR 1.96, 95% CI 1.51–2.56; P < 0.0001) were associated with shorter TTR in patients with distal tumors and a trend was found for codon 13 (HR 1.59, 95% CI 1.00–2.56; P = 0.051) (Figure 3B). The interaction tests between KRAS mutation status and tumor location on TTR (P = 0.02) and DFS (P = 0.042) and between KRAS WT, codon 12 mutations, p.G13D and location on TTR (P = 0.01) and DFS (P = 0.01), were all positive. Finally, an interaction test was carried out and we could not find a survival effect of p.G13D mutation when compared with p.G12X for TTR (HR 0.75; 95% CI 0.52–1.08; NS) or DFS (HR 0.78; 95% CI 0.55–1.10; NS). Figure 3C summarizes the impact of individual mutation on TTR in both locations.
discussion We genotyped tumors from 1810 patients enrolled in a randomized phase III trial for KRAS exon 2 and BRAF mutations. The impact of KRAS mutations on TTR and DFS was studied excluding samples with BRAF mutations (8.45%), given that BRAF status itself affects the prognosis. The detection method used for genotyping was validated through various external quality control programs (European Society of Pathology KRAS EQA schemes). As expected in CRC (COSMIC database), KRAS exon 2 mutations were located at codons 12 and 13 in 79% and 21% of the samples, respectively. Large population-based cohorts restricted to nonmetastatic CRC patients have yielded to different results concerning the prognostic value of KRAS mutations [11–13, 18, 19]. For
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Treatment group Folfox versus Folfox + Cetuximab Mutation Wild-type versus mutated Gender Female versus male Age <70 years versus ≥70 years Histopathological grade G1–G2 versus G3–G4 Tumor location Distal cancer versus proximal cancer PT PT1 versus PT2 PT1 versus PT3 PT1 versus PT4 PN PN1 versus PN2 Bowel obstruction and perforation Bowel obstr. and/or perf. versus no bowel obstr. and no perf. VELI Vascular invasion or lymphatic infiltration versus no vascular invasion and no lymphatic infiltration
HR
TTR was significantly shorter (HR 1.56, 95% CI 1.28–1.92; P < 0.001) in KRAS-mutated patients (Figure 2B), with a higher rate of relapse (30% versus 19%, P < 0.001). Codon 12 alterations (HR 1.67, 95% CI 1.35–2.04) but not the p.G13D mutation (HR 0.81, 95% CI 0.56–1.17) were associated with shorter TTR (Figure 2C). Figure 2D summarizes the impact of individual mutation on TTR. In univariate analysis, high-grade tumors (P = 0.0001); stage pT4 (P = 0.0006); stage pN2 (P < 0.0001); obstruction or perforation (P = 0.0001); vascular embolism and/or lymphatic invasion (P = 0.015); KRAS mutations (P < 0.0001) and KRAS codon 12 mutations (P < 0.0001) were all associated with shorter TTR (supplementary Data S2, available at Annals of Oncology online). In multivariate analysis including all significant variables, KRAS mutations (P < 0.001), high-grade tumors (P = 0.012), pT4 (P = 0.009) and pN2 (P < 0.001) remained associated with shorter TTR (Table 2). Similar results were obtained for DFS (supplementary Data S3–S5, available at Annals of Oncology online).
original articles
Annals of Oncology
A
Proximal 12% 8%
1%
54%
17%
5% 3%
Wild-type Codon 12 Codon 13
C
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
11% 3% 3%
NS Wild-type Codon 12 Codon 13
WT G12A G12C G12D G12S G12R G12V G13D
6% 8%
Years
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
66%
P < 0.001 Wild-type Codon 12 Codon 13
Years
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
316 201 69
282 168 62
209 145 46
162 120 47
54 41 18
2 2 1
0 0 0
0 0 0
692 285 66
641 242 59
476 198 51
334 175 39
128 72 14
3 2 0
0 0 0
0 0 0
Codon 12 p.G12A p.G12C p.G12D p.G12S p.G12R p.G12V Codon 13
Codon 12 p.G12A p.G12C p.G12D p.G12S p.G12R p.G12V Codon 13 2
4 6 8 12 18
0.1
1
10
Figure 3. Time to recurrence according to KRAS status for proximal and distal colon cancers. (A) KRAS mutation types in the PETACC8 trial population. (B) In proximal tumors, KRAS mutation status had no impact on time to recurrence (P = 0.69) whereas KRAS codon 12 mutations were associated with TTR in distal cancers (P < 0.001), and a trend was observed for codon 13 (P = 0.051). The individual impact of mutations is shown on figure (C) for proximal and distal cancers.
example, no association between KRAS mutations and relapse or survival was found in the PETACC-3 trial among 1404 CRC patients treated with 5-FU +/− irinotecan [12]. In contrast, the Quasar study [20], which mainly included stage II patients, showed an increased risk of recurrence among KRAS-mutated patients, which was not affected by adjuvant chemotherapy. The RASCAL population-based studies [13, 14] showed that KRAS p.G12V only, was associated with poorer outcome and Imamura et al. found that codon 12 but not codon 13 (HR 1.25; 95% CI 0.85–1.84; NS) mutations negatively affected cancer specific mortality [11]. In contrast, data from the NCCTG NO147 trial, which had a similar design to PETACC-08, showed that KRAS mutations at codons 12 (HR 1.52; 95% CI 1.28–1.8; P < 0.0001) and codon 13 (HR 1.36, 95% CI 1.04–1.72; P = 0.025) had a prognostic value [21, 22]. This may be due to the heterogeneity of the study populations, which included colon and rectal cancer, stage I–III tumors, patients receiving or not adjuvant treatments, patients with and without BRAF mutations and data from population-based cohorts or from clinical trials. In PETACC8 patients (n = 1657), KRAS codon 12 mutations were related to shorter TTR and DFS. Subsequently, we studied the impact of KRAS mutations on TTR and DFS according to
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tumor location [23]. Proximal tumors were more frequently KRAS-mutated than were distal tumors. Previous studies also reported higher KRAS mutation rates in proximal when compared with distal colon cancer [12, 23], but the relationship between cancer location, KRAS status and outcome remains unclear [23–25]. Here, no effect of KRAS mutations was found for proximal tumors. In contrast, codon 12 alterations had a negative impact on TTR in patients with distal tumors and although the test did not reach statistical significance for p.G13D (P = 0.051), there was a clear trend for a similar effect. This borderline significance is possibly due to the poor number of events and patients in this subgroup. Larger series are needed to definitely state on the prognostic impact of p.G13D in colon tumors. One limitation of our study is that MMR status was not available for patients enrolled in the PETACC8 trial. Deficient MMR phenotype tumors are mainly located in the proximal colon, associated with low recurrence rates, BRAF mutations and KRAS p.G13D [26–28]. We estimated that more than 50% of MSI-H cancers (10–15% of CCR) were excluded through the exclusion of BRAF-mutated cancers that tends to limit the possible confounding role of MSI status in our series and suggests that our results, by approximation refer to an MSS population.
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Time to recurrence
B
1% 2%
Time to recurrence
0%
Distal WT G12A G12C G12D G12S G12R G12V G13D
original articles
acknowledgements We thank J. F. Côté for his skillful expertise in reviewing and selecting tumor samples for molecular analysis and T. Kombi for her technical assistance. We thank all PETACC-8 study investigators.
funding The study was sponsored by the Fédération Francophone de Cancérologie Digestive (FFCD) that was responsible for the study management. Merck KGaA and Sanofi-Aventis supported the study: Merck provided the study cetuximab and financial support for study management; Sanofi-Aventis provided financial support for the provision of oxaliplatin to Belgian sites when necessary. JT had full access to the data and had final responsibility for the decision to submit for publication.
disclosure JT received honoraria from Sanofi and Merck KGaA. J-FE received honoraria from Merck Serono. JT received honoraria from Amgen, Merck KGaA and Sanofi. GF declared research funding from Merck KGaA and honoraria from Merck KGaA, Roche, Lilly, BMS and Amgen; JT declared research funding and honoraria from Sanofi and Merck; JB declared advisory roles for Merck, Sanofi and Roche; LNP declared advisory roles for Roche and Bayer; EVC declared receiving research funding from Merck Serono paid to his institution. RS declared advisory roles and lectures for Merck KGaA and Amgen. PL-P declared providing advisory roles and lectures for Sanofi, Merck Serono, Amgen, Roche, Genomic Health, Myriad Genetics, and Pfizer. All remaining authors have declared no conflicts of interest.
references 1. Boyle P, Langman JS. ABC of colorectal cancer: epidemiology. BMJ 2000; 321 (7264): 805–808. 2. Jemal A, Siegel R, Ward E et al. Cancer statistics, 2008. CA Cancer J Clin 2008; 58(2): 71–96. 3. Andre T, Boni C, Navarro M et al. Improved overall survival with oxaliplatin, fluorouracil, and leucovorin as adjuvant treatment in stage II or III colon cancer in the MOSAIC trial. J Clin Oncol 2009; 27(19):3109–3116.
| Blons et al.
4. Karapetis CS, Khambata-Ford S, Jonker DJ et al. K-ras mutations and benefit from cetuximab in advanced colorectal cancer. N Engl J Med 2008; 359(17): 1757–1765. 5. Vogelstein B, Fearon ER, Hamilton SR et al. Genetic alterations during colorectaltumor development. N Engl J Med 1988; 319(9): 525–532. 6. Forbes SA, Bindal N, Bamford S et al. COSMIC: mining complete cancer genomes in the Catalogue of Somatic Mutations in Cancer. Nucleic Acids Res 2011; 39 (Database issue): D945–D950. 7. Bokemeyer C, Bondarenko I, Hartmann JT et al. Efficacy according to biomarker status of cetuximab plus FOLFOX-4 as first-line treatment for metastatic colorectal cancer: the OPUS study. Ann Oncol 2011; 22(7): 1535–1546. 8. Lievre A, Bachet JB, Boige V et al. KRAS mutations as an independent prognostic factor in patients with advanced colorectal cancer treated with cetuximab. J Clin Oncol 2008; 26(3): 374–379. 9. Van Cutsem E, Kohne CH, Hitre E et al. Cetuximab and chemotherapy as initial treatment for metastatic colorectal cancer. N Engl J Med 2009; 360(14): 1408–1417. 10. Gavin PG, Colangelo LH, Fumagalli D et al. Mutation profiling and microsatellite instability in stage II and III colon cancer: an assessment of their prognostic and oxaliplatin predictive value. Clin Cancer Res 2012; 18(23): 6531–6541. 11. Imamura Y, Morikawa T, Liao X et al. Specific mutations in KRAS codons 12 and 13, and patient prognosis in 1075 BRAF wild-type colorectal cancers. Clin Cancer Res 2012; 18(17): 4753–4763. 12. Roth AD, Tejpar S, Delorenzi M et al. Prognostic role of KRAS and BRAF in stage II and III resected colon cancer: results of the translational study on the PETACC-3, EORTC 40993, SAKK 60–00 trial. J Clin Oncol 2010; 28(3): 466–474. 13. Andreyev HJ, Norman AR, Cunningham D et al. Kirsten ras mutations in patients with colorectal cancer: the ‘RASCAL II’ study. Br J Cancer 2001; 85(5): 692–696. 14. Andreyev HJ, Norman AR, Cunningham D et al. Kirsten ras mutations in patients with colorectal cancer: the multicenter ‘RASCAL’ study. J Natl Cancer Inst 1998; 90(9): 675–684. 15. Morikawa T, Kuchiba A, Qian ZR et al. Prognostic significance and molecular associations of tumor growth pattern in colorectal cancer. Ann Surg Oncol 2012; 19(6): 1944–1953. 16. Taieb J, Tabernero J, Mini E et al. Oxaliplatin, fluorouracil, and leucovorin with or without cetuximab in patients with resected stage III colon cancer (PETACC-8): an open-label, randomised phase 3 trial. Lancet Oncol 2014; 15(8): 862–873. 17. Blons H, Rouleau E, Charrier N et al. Performance and cost efficiency of KRAS mutation testing for metastatic colorectal cancer in routine diagnosis: the MOKAECM study, a nationwide experience. PLoS One 2013; 8(7): e68945. 18. Farina-Sarasqueta A, van Lijnschoten G, Moerland E et al. The BRAF V600E mutation is an independent prognostic factor for survival in stage II and stage III colon cancer patients. Ann Oncol 2010; 21(12): 2396–2402. 19. Yokota T. Are KRAS/BRAF mutations potent prognostic and/or predictive biomarkers in colorectal cancers? Anticancer Agents Med Chem 2011; 12(2): 163–171. 20. Hutchins G, Southward K, Handley K et al. Value of mismatch repair, KRAS, and BRAF mutations in predicting recurrence and benefits from chemotherapy in colorectal cancer. J Clin Oncol 2011; 29(10): 1261–1270. 21. Yoon H, Tougeron D, Mahoney M et al. Prognostic impact of specific KRAS mutations in codon 12 and 13 in 2,165 BRAF-wildtype colon cancers: results from NCCTG N0147 (Alliance). Eur J Cancer 2013; 49: S484. 22. Yoon HH, Tougeron D, Shi Q et al. KRAS codon 12 and 13 mutations in relation to disease-free survival in BRAF-wild-type stage III colon cancers from an adjuvant chemotherapy trial (N0147 alliance). Clin Cancer Res 2014; 20(11): 3033–3043. 23. Benedix F, Meyer F, Kube R et al. Influence of anatomical subsite on the incidence of microsatellite instability, and KRAS and BRAF mutation rates in patients with colon carcinoma. Pathol Res Pract 2012; 208(10): 592–597. 24. Hansen IO, Jess P. Possible better long-term survival in left versus right-sided colon cancer—a systematic review. Dan Med J 2012; 59(6): A4444. 25. Weiss JM, Pfau PR, O’Connor ES et al. Mortality by stage for right- versus leftsided colon cancer: analysis of surveillance, epidemiology, and end results— Medicare data. J Clin Oncol 2011; 29(33): 4401–4409.
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Another limitation is the lack of data on rare KRAS and NRAS mutations. In a small cohort of patients, KRAS exon3/4- and NRAS-mutated tumors were associated to a better prognostic when compared with exon 2 alterations [29] but large prospective series are still needed to validate the prognostic impact of rare KRAS an NRAS alterations in CCR. In conclusion, we show in a series of stage III CCR patients included in a randomized, controlled phase III trial that codon 12 KRAS mutations have a significant impact on the TTR in distal CRC. The impact of the p.G13D mutation needs to be refined in a larger series according to tumor location and tumor phenotype (MSS/MSI) although this study suggests that p.G13D distal CRC might behave as p.G12X tumors. Future clinical trials in stage III colon cancer should consider both the tumor location and KRAS mutational status as important stratification factors.
Annals of Oncology
original articles
Annals of Oncology 26. Oliveira C, Westra JL, Arango D et al. Distinct patterns of KRAS mutations in colorectal carcinomas according to germline mismatch repair defects and hMLH1 methylation status. Hum Mol Genet 2004; 13(19): 2303–2311. 27. Phipps AI, Buchanan DD, Makar KW et al. BRAF mutation status and survival after colorectal cancer diagnosis according to patient and tumor characteristics. Cancer Epidemiol Biomarkers Prev 2012; 21(10): 1792–1798.
28. Phipps AI, Buchanan DD, Makar KW et al. KRAS-mutation status in relation to colorectal cancer survival: the joint impact of correlated tumour markers. Br J Cancer 2013; 108(8): 1757–1764. 29. Janakiraman M, Vakiani E, Zeng Z et al. Genomic and biological characterization of exon 4 KRAS mutations in human cancer. Cancer Res 2010; 70(14): 5901–5911.
Annals of Oncology 25: 2385–2391, 2014 doi:10.1093/annonc/mdu463 Published online 3 October 2014
Q. Zhou1, Y. Cheng2, J.-J. Yang1, M.-F. Zhao3, L. Zhang4, X.-C. Zhang1, Z.-H. Chen1, H.-H. Yan1, Y. Song5, J.-H. Chen6, W.-N. Feng7, C.-R. Xu1, Z. Wang1, H.-J. Chen1, W.-Z. Zhong1, Y.-P. Liu3 & Y.-L. Wu1* 1
Department of Pulmonary Oncology, Guangdong Lung Cancer Institute, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou; Department of Pulmonary Oncology, Jilin Provincial Cancer Hospital, Changchun; 3Department of Medical Oncology, The First Hospital of China Medical University, Shenyang; 4Department of Respiratory Medicine, Perking Union Medical Hospital, Beijing; 5Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing; 6Department of Medical Oncology, Hunan Cancer Hospital, Changsha; 7Department of Medical Oncology, The First People’s Hospital of Foshan, Foshan, China 2
Received 30 May 2014; revised 1 September 2014 and 23 September 2014; accepted 23 September 2014
Background: CTONG0806 assessed the efficacy of pemetrexed versus gefitinib as second-line treatment in advanced nonsquamous nonsmall-cell lung cancer (NSCLC) harboring wild-type epidermal growth factor receptor (EGFR). Patients and methods: Patients with locally advanced or metastatic nonsquamous NSCLC harboring wild-type EGFR, detected by direct sequencing, and previously treated with platinum-based chemotherapy were randomized to receive gefitinib (250 mg/day) orally or pemetrexed (500 mg/m2) i.v. on day 1 of a 21-day cycle until disease progression or unacceptable toxicity. The primary end point was progression-free survival (PFS). The Independent Review Committee (IRC) evaluated all pictorial data. Results: From February 2009 to August 2012, 161 patients were enrolled, and 157 were assessable (81 in the gefitinib arm, 76 in the pemetrexed arm). Baseline characteristics were balanced between the two arms. The median PFSs were 4.8 versus 1.6 months in the pemetrexed and gefitinib arms, respectively [hazard ratio (HR) 0.54, 95% confidence interval (CI) 0.40–0.75, P < 0.001] as confirmed by IRC evaluation (5.6versus 1.7 months, HR 0.53, 95% CI 0.38–0.75, P < 0.001). The median overall survival (OS) showed a trend of superiority in the pemetrexed arm (12.4 versus 9.6 months, HR 0.72, 95% CI 0.49–1.04, P = 0.077). Quality-of-life assessment showed no marked difference between the arms. No unexpected adverse events were found. Of 108 patients with sufficient DNA samples, EGFR mutation status was re-tested by Scorpion amplification refractory mutation system (ARMS); 32 (29.6%) tested positive (19 in the pemetrexed arm, 13 in the gefitinib arm; median PFS: 8.1 versus 7.0 months, HR 0.94, 95% CI 0.43–2.08, P = 0.877). *Correspondence to: Dr Yi-Long Wu, Guangdong Lung Cancer Institute, Guangdong General Hospital and Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, China. Tel: +86-20-83877855; Fax: +86-20-83827712; E-mail: [email protected] †
Data from this study were previously accepted for oral presentation at the 15th World Conference on Lung Cancer (WCLC), Sydney, Australia, 28–30 September 2013, and was selected to be released in press conference during this WCLC.
© The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: [email protected].
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Pemetrexed versus gefitinib as a second-line treatment in advanced nonsquamous nonsmall-cell lung cancer patients harboring wild-type EGFR (CTONG0806): a multicenter randomized trial†
19. Gilardini Montani MS, Prodosmo A, Stagni V et al. ATM-depletion in breast cancer cells confers sensitivity to PARP inhibition. J Exp Clin Cancer Res 2013; 32: 95. 20. Min A, Im SA, Yoon YK et al. RAD51C-deficient cancer cells are highly sensitive to the PARP inhibitor olaparib. Mol Cancer Ther. 2013; 12: 865–877. 21. Koppensteiner R, Samartzis EP, Noske A et al. Effect of MRE11 loss on PARP-inhibitor sensitivity in endometrial cancer in vitro. PLoS One 2014; 9: e100041. 22. Ibragimova I, Cairns P. Assays for hypermethylation of the BRCA1 gene promoter in tumor cells to predict sensitivity to PARP-inhibitor therapy. Methods Mol Biol 2011; 780: 277–291. 23. Drew Y, Mulligan EA, Vong WT et al. Therapeutic potential of poly(ADP-ribose) polymerase inhibitor AG014699 in human cancers with mutated or methylated BRCA1 or BRCA2. J Natl Cancer Inst 2011; 103(4): 334–346.
Annals of Oncology 25: 2378–2385, 2014 doi:10.1093/annonc/mdu464 Published online 6 October 2014
Prognostic value of KRAS mutations in stage III colon cancer: post hoc analysis of the PETACC8 phase III trial dataset H. Blons1,2,3, †, J. F. Emile4,5,†, K. Le Malicot6, †, C. Julié4, A. Zaanan7, J. Tabernero8, E. Mini9, G. Folprecht10, J. L. Van Laethem11, J. Thaler12, J. Bridgewater13, L. Nørgård-Petersen14, E. Van Cutsem15, C. Lepage16, M. A. Zawadi17, R. Salazar18, P. Laurent-Puig1,2,3,† & J. Taieb7,2, †* 1 UMR-S1147, INSERM, Paris; 2Paris Descartes University, Paris; 3APHP Department of Biology, Georges Pompidou Hospital, Paris; 4Department of Pathology, APHP Ambroise Paré Hospital, Boulogne-Billancourt; 5Paris-Ouest University, Versailles Saint-Quentin; 6Department of Statistics, Fédération Francophone de Cancérologie Digestive, Dijon; 7APHP Department of Hepatogastroenterology and GI Oncology, Georges Pompidou Hospital, Paris, France; 8Department of Medical Oncology, Vall d‘Hebron University Hospital and Institute of Oncology (VHIO), Barcelona, Spain; 9Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy; 10 1st Medical Department, University Hospital Carl Gustav Carus, Dresden, Germany; 11Deptartment of Gastroenterology, Erasme University Hospital, Brussels, Belgium; 12 Department of Internal Medicine IV, Klinikum Wels-Grieskirchen, Wels, Austria; 13UCL Cancer Institute, University College London, London, UK; 14Department of Oncology, Rigshospitalet, København, Denmark; 15Department of Digestive Oncology, University Hospitals and KULeuven, Leuven, Belgium; 16Department of Hepato-Gastroenterology, Dijon University Hospital and INSERM U 866, Dijon; 17GI Oncology, Les Oudairies Hospital, La Roche sur Yon, France; 18Catalan Institute of Oncology (IDIBELL), Barcelona, Spain
Received 10 July 2014; revised 18 September 2014; accepted 18 September 2014
Background: The prognostic value of KRAS mutations in colon adenocarcinoma is controversial. We examined this question as an ancillary study of the PETACC8 phase III trial. Patients and methods: We analyzed the pronostic impact of KRAS exon 2 mutations in stage III colon cancer patients (n = 1657) receiving adjuvant FOLFOX ± cetuximab therapy included in the PETACC8 trial. Patients with BRAF-mutated cancers were excluded and, as no difference was found for time to recurrence (TTR) and disease-free survival (DFS) between treatment arms, both were pooled for analysis. Associations with TTR and DFS were analyzed using a Cox proportional hazards model. Results: KRAS mutations were found in 638 of 1657 tumors and linked to shorter TTR (P < 0.001). However, when specific mutations were compared with wild-type, codon 12 mutations [hazard ratio (HR) 1.67, 95% confidence interval (CI) 1.35–2.04; P < 0.001] but not codon 13 (HR 1.23, 95% CI 0.85–1.79; P = 0.26) were significantly associated with shorter *Correspondence to: Dr Julien Taieb, Georges Pompidou Hospital, Department of Hepatogastroenterology and GI Oncology, Université Paris Descartes, 20 rue Leblanc, 75015 Paris, France. Tel: +33-1-5609351; Fax: +33-1-56093441; E-mail: julien.taieb@ egp.aphp.fr †
These authors contributed equally.
© The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: [email protected].
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15. Vaz FH, Machado PM, Brandao RD et al. Familial breast/ovarian cancer and BRCA1/2 genetic screening: the role of immunohistochemistry as an additional method in the selection of patients. J Histochem Cytochem 2007; 55(11): 1105–1113. 16. Carser JE, Quinn JE, Michie CO et al. BRCA1 is both a prognostic and predictive biomarker of response to chemotherapy in sporadic epithelial ovarian cancer. Gynecol Oncol 2011; 123(3): 492–498. 17. Radosa MP, Hafner N, Camara O et al. Loss of BRCA1 protein expression as indicator of the BRCAness phenotype is associated with favorable overall survival after complete resection of sporadic ovarian cancer. Int J Gynecol Cancer 2011; 21(8): 1399–1406. 18. Weberpals JI, Tu D, Squire JA et al. Breast cancer 1 (BRCA1) protein expression as a prognostic marker in sporadic epithelial ovarian carcinoma: an NCIC CTG OV.16 correlative study. Ann Oncol 2011; 22(11): 2403–2410.
Annals of Oncology
original articles
Annals of Oncology
TTR, independently of other covariates. The interaction test showed that, regarding tumor location (distal versus proximal), KRAS genotype affects differently on recurrence (P = 0.02) and DFS (P = 0.042). Subgroup analysis showed that KRAS only affected TTR and DFS in distal tumors (n = 1043; 692 wild type; 351 mutated), with an increased risk of relapse (HR 1.96, 95% CI 1.51–2.56; P < 0.0001) for KRAS codon 12 mutations and a borderline significance for codon 13 mutations (HR 1.59, 95% CI 1.00–2.56; P = 0.051). Conclusion: KRAS exon 2 mutations are independent predictors of shorter TTR in patients with resected stage III distal colon cancers receiving adjuvant therapy. Future clinical trials in the adjuvant setting should consider both the tumor location and KRAS mutations as important stratification factors. Clinical trial number: This is an ancillary study of the PETACC8 trial: EUDRACT 2005-003463-23. Key words: colorectal cancer, KRAS mutation, cetuximab, proximal colon, distal colon, prognosis
Colorectal cancer (CRC) is the fourth cause of cancer death worldwide [1, 2]. Despite advances in drug therapy and the use of targeted treatments [3, 4], many patients with completely resected cancers still die of metastatic relapses, reflecting a biological heterogeneity, which is not fully understood. CRC occurs through a multistep process driven by the accumulation of genetic alterations, of which KRAS activating mutations are considered one of the earliest [5]. They are present in ∼45% of CRCs and exclusive of other genetic alterations in EGFR pathway activators such as BRAF and NRAS. KRAS mutations at codons 12 and 13 are the most frequent alterations in CRC, representing more than 90% of all mutations [6]. KRAS status was shown to be a predictive marker of resistance to EGFR inhibitors, leading to restricted use of these drugs in patients with KRAS wild-type metastatic CRC [7–9]. In contrast, the influence of KRAS mutations on outcome is less evident. In resected colon cancer patients, KRAS mutational status has been linked to disease recurrence and poorer overall survival in recent large prospective cohorts and clinical trials but discrepancies remain [10–12]. In BRAF wild-type CRC, a poor prognosis was either related to KRAS mutations or restricted to patients with codon 12 mutated tumors [11, 13–15]. This post hoc study of the PETACC8 [16] phase III trial analyzed the impact of individual KRAS mutations on time to recurrence (TTR) and disease-free survival (DFS) in stage III CRC patients undergoing surgery and standard 5-fluorouracil (5-FU) and oxaliplatin-based adjuvant therapy and refined the results according to tumor location.
materials and methods patient characteristics Patients from the PETACC8 trial had completely resected, histologically proven stage III colon adenocarcinoma and were randomized to receive, as adjuvant treatment, either 6 months of FOLFOX 4 or FOLFOX 4-cetuximab [16]. The trial started in December 2005, it was amended in June 2008 to enroll patients with KRAS wild-type tumors. Written informed consent was required for patients’ participation to the PETACC8 planned translational program.
DNA extraction and mutation analysis Tumor DNAs were extracted from formalin-fixed and paraffin-embedded (FFPE) tissues using the QIAamp® DNA Mini Kit (Qiagen®). Molecular analysis was centralized and carried out retrospectively for 2096 patients
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included before trial amendment, and prospectively for the other 463 patients, by real-time PCR using TaqMan® probes (Applied Biosystems) for KRAS (c.34G > A/p.G12S, c.34G > C/p.G12R, c.34G > T/p.G12C, c.35G > A/ p.G12D, c.35G > C/p.G12A, c.35G > T/p.G12V and c.38G > A p.G13D) and BRAF (c.1799T > A/p.V600E). Each assay was validated to detect 10% of mutated alleles [17].
statistical analysis Patients were divided into two groups: group 1 with mutant KRAS/BRAF and group 2 with wild-type KRAS/BRAF. Comparisons of patients with specific mutations versus the wild-type population only concerned mutations representing more than 10% of all mutations detected this study. The end points for these analyses were TTR and DFS. TTR was defined as the time between the date of randomization and the date of local or metastatic recurrence. DFS was defined as the time between the date of randomization and the date of local or metastatic recurrence, second colon cancer or death, whichever occurred first. Overall survival data are not yet available for the PETACC8 trial and were thus not reported in this work. For comparisons of baseline characteristics, categorical outcomes were analyzed with χ 2 tests and continuous outcomes were compared with standard parametric or nonparametric tests. Continuous variables are presented as the mean (SD) and median interquartile range. TTR and DFS curves were estimated with the Kaplan–Meier method. Differences between groups of patients were analyzed using unstratified logrank tests. An unstratified Cox regression model was used to estimate hazard ratios (HRs), 95% confidence intervals (CIs) and P values for candidate prognostic factors. Factors included in the multivariate analyses were the treatment group, baseline variables imbalanced between the two PETACC8 arms, and prognostic factors identified in univariate analyses. The WHO 6th edition criteria were used for tumor staging. Analyses were carried out according to the intention-to-treat principle with a two-sided significance level of 5%. Results were unadjusted for multiple comparisons. All statistical analyses were done with the SAS statistical software package (version 9.4).
results study population Among the 2559 patients included in the PETACC8 phase III study, 1810 met all the criteria for molecular analysis (informed consent and available FFPE sample, no technical failure for KRAS/BRAF status determination), 153 were BRAF-mutated and excluded because of the prognostic impact of BRAF mutations (Figure 1), 1 tumor was KRAS- and BRAF-mutated and was also excluded of the analysis. Demographic and clinical characteristics of the patients in the KRAS molecular study (n =
doi:10.1093/annonc/mdu464 |
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introduction
original articles
Annals of Oncology
PETACC8 population n = 2559
KRAS not determined - No informed consent - Black not received - Insufficient material - Technical failure n = 624 (excluded)
KRAS Mut n = 638
KRAS WT n = 1297
BRAF not determined
- Insufficient material - Technical failure n = 125 (excluded) KRAS WT tested for BRAF n = 1172
KRAS WT/BRAD WT n = 1019
KRAS WT/BRAF Mut n = 153 (excluded)
Figure 1. Flow chart of PETACC8 trial molecular study evaluating the impact of KRAS mutations on time to recurrence and DFS in the BRAF wild-type sample population.
A
WT 8%
G12A
8%
Time to recurrence
0%
B
G12C
2%
G12D
13%
G12S
62%
G12R
4%
G12V
3%
G13D
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
P < 0.001 Mutated Wild-type 0
Wild-type 1019 Mutated 638
D
C
Time to recurrence
Codon 12 p.G12A p.G12C p.G12D p.G12S p.G12R p.G12V Codon 13
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
2
3 4 5
2
3
4
5
6
7 Years
933 547
693 465
501 394
182 150
5 5
0 0
0 0
P = 0.26 P < 0.001
Wild-type Codon 12 Codon 13 0
1
1
Wild-type 1019 Codon 12 502 Codon 13 136
1
2
3
4
5
6
7 Years
933 425 122
693 357 108
501 307 87
182 117 33
5 4 1
0 0 0
0 0 0
Figure 2. Time to recurrence according to KRAS status. (A) KRAS mutation types in the PETACC8 trial population. (B) In the entire population, KRAS status is related to shorter time to recurrence (P < 0.01). (C) Subsequent analysis showed that codon 12 (P < 0.01) but not codon 13 (P = 0.26) are associated with shorter time to recurrence. (D) Impact of individual alterations on time to recurrence, results or not statistically relevant for p.G12S and p.G12R due to the small number of tumors in these groups.
| Blons et al.
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- No translational research informed consent
original articles
Annals of Oncology
Table 1. Analyzed population—demographic and clinical characteristics Mutated (N = 638)
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P value
638 316 (38.1%) 322 (38.9%)
1019 513 (61.9%) 506 (61.1%)
χ 2: 0.7472
638 350 (36.5%) 288 (41.3%)
1019 610 (63.5%) 409 (58.61%)
χ 2: 0.0447
638 59.85 (9.42) 61.00 54.00; 67.00 23.00; 74.00
1019 58.79 (9.77) 60.00 53.00; 66.00 19.00; 75.00
W: 0.0301
638 562 (38.0%) 76 (42.9%) 0 (0.0)
1019 918 (62.0%) 101 (57.1%) 0 (0.0)
χ 2: 0.1995
613 503 (32.2%) 108 (38.8%) 2 (40%) 0 (0.0)
988 814 (61.8%) 170 (61.2%) 3 (60%) 1 (100%)
χ 2: 0.8805
634 351 (33.7%) 270 (46.1%) 13 (65%)
1015 692 (66.3%) 316 (53.9%) 7 (35%)
χ 2: <0.0001
630 131 (37.5%) 393 (39.1%) 103 (37.6%) 3 (33.3%)
1007 218 (62.5%) 612 (60.9%) 171 (62.4%) 6 (66.7%)
χ 2: 0.921
638 407 (38.7%) 231 (38.1%)
1019 644 (61.3%) 375 (61.9%)
χ 2: 0.8070
638 14 (30.4%) 37 (31.1%) 440 (38.5%) 147 (42.4%) 0 (0.0)
1019 32 (69.6%) 82 (68.9%) 703 (61.5%) 200 (57.6%) 2 (100%)
χ 2: 0.1135
638 134 (42.5%) 504 (37.6%)
1019 181 (57.5%) 838 (62.4%)
χ 2: 0.1019
638 323 (35.3%) 210 (42.4%) 105 (42.7%)
1019 593 (64.7%) 285 (57.6%) 141 (57.3%)
χ 2: 0.0106
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Treatment group n Folfox Folfox + Cetux Gender n Male Female Age n Moy. (SD) Median Q1; Q3 Min; max Age (Class) n Age ≤70 years Age >70 years Missing WHO performance status n 0 1 2 3 Tumor location n Distal colon Proximal colon Both sides Histopathology grading n Well differentiated Moderately differentiated Poorly differentiated Undifferentiated Pn classification n pN1 pN2 PT classification n pT1 pT2 pT3 pT4 pTx Bowel obstruction and perforation n Bowel obstruction and/or perforation No bowel obstruction and no perforation VELI n Vascular invasion or lymphatic infiltration No vascular invasion and no lymphatic infiltration Unknown
Wild-type (N = 1019)
original articles
Annals of Oncology
Table 2. Multivariate analysis and time to recurrence (TTR) N = 1629
Confidence interval (95%)
P-value
1.03
0.84
1.25
0.812
1.58
1.28
1.94
<0.0001
0.95
0.77
1.17
0.634
0.94
0.68
1.31
0.73
1.37
1.07
1.76
0.012
0.86
0.69
1.07
0.164
0.81 1.95 3.82
0.25 0.72 1.40
2.63 5.26 10.4
2.24
1.82
2.77
<0.0001
0.84
0.66
1.07
0.165
0.97
0.76
1.24
0.804
0.722 0.189 0.009
Bold values are to underline significance in the results.
1657) were not significantly different from those of the excluded population (supplementary data S1, available at Annals of Oncology online).
KRAS results Of the 1657 tumors, 38.5% had a KRAS mutation, located on codon 12 in 79% of the cases. Detailed repartition is shown on Figure 2A. KRAS mutations were more frequent in women, in proximal CRC, and were associated with age, and no vascular or lymphatic infiltration (Table 1).
outcome predictors In the PETACC8 trial, KRAS-mutated tumors were equally numerous in both treatment arms. Moreover, an interaction test was carried out between KRAS status (WT, codon 12 and codon13) and treatment (TTR P = 0.37; DFS P = 0.32) leading to the conclusion that both arms could be pooled to study the impact of KRAS mutations on TTR and DFS. Median follow-up was 3.4 years (95% CI 3.3–3.4) and 3.8 years (95% CI 3.8–3.9) for patients with wild-type and mutated tumors, respectively.
| Blons et al.
subgroup analysis We looked for a different impact of KRAS mutations on TTR and DFS between men and women. The results showed that KRAS codon 12 alterations were related to shorter TTR in both women and men (respectively, HR 1.78, 95% CI 1.29–2.46; P = 0.0004 and HR 1.58, 95% CI 1.19–2.09; P = 0.001). In proximal cancer, KRAS mutations were more frequent than in distal cancer, with a higher proportion of p.G13D and p. G12D alterations (Figure 3A) but had no impact on TTR (HR 1.29, 95% CI 0.90–1.84; NS; HR 0.89; 95% CI 0.50–1.59; NS) (Figure 3B). At the opposite, codon 12 alterations (HR 1.96, 95% CI 1.51–2.56; P < 0.0001) were associated with shorter TTR in patients with distal tumors and a trend was found for codon 13 (HR 1.59, 95% CI 1.00–2.56; P = 0.051) (Figure 3B). The interaction tests between KRAS mutation status and tumor location on TTR (P = 0.02) and DFS (P = 0.042) and between KRAS WT, codon 12 mutations, p.G13D and location on TTR (P = 0.01) and DFS (P = 0.01), were all positive. Finally, an interaction test was carried out and we could not find a survival effect of p.G13D mutation when compared with p.G12X for TTR (HR 0.75; 95% CI 0.52–1.08; NS) or DFS (HR 0.78; 95% CI 0.55–1.10; NS). Figure 3C summarizes the impact of individual mutation on TTR in both locations.
discussion We genotyped tumors from 1810 patients enrolled in a randomized phase III trial for KRAS exon 2 and BRAF mutations. The impact of KRAS mutations on TTR and DFS was studied excluding samples with BRAF mutations (8.45%), given that BRAF status itself affects the prognosis. The detection method used for genotyping was validated through various external quality control programs (European Society of Pathology KRAS EQA schemes). As expected in CRC (COSMIC database), KRAS exon 2 mutations were located at codons 12 and 13 in 79% and 21% of the samples, respectively. Large population-based cohorts restricted to nonmetastatic CRC patients have yielded to different results concerning the prognostic value of KRAS mutations [11–13, 18, 19]. For
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Treatment group Folfox versus Folfox + Cetuximab Mutation Wild-type versus mutated Gender Female versus male Age <70 years versus ≥70 years Histopathological grade G1–G2 versus G3–G4 Tumor location Distal cancer versus proximal cancer PT PT1 versus PT2 PT1 versus PT3 PT1 versus PT4 PN PN1 versus PN2 Bowel obstruction and perforation Bowel obstr. and/or perf. versus no bowel obstr. and no perf. VELI Vascular invasion or lymphatic infiltration versus no vascular invasion and no lymphatic infiltration
HR
TTR was significantly shorter (HR 1.56, 95% CI 1.28–1.92; P < 0.001) in KRAS-mutated patients (Figure 2B), with a higher rate of relapse (30% versus 19%, P < 0.001). Codon 12 alterations (HR 1.67, 95% CI 1.35–2.04) but not the p.G13D mutation (HR 0.81, 95% CI 0.56–1.17) were associated with shorter TTR (Figure 2C). Figure 2D summarizes the impact of individual mutation on TTR. In univariate analysis, high-grade tumors (P = 0.0001); stage pT4 (P = 0.0006); stage pN2 (P < 0.0001); obstruction or perforation (P = 0.0001); vascular embolism and/or lymphatic invasion (P = 0.015); KRAS mutations (P < 0.0001) and KRAS codon 12 mutations (P < 0.0001) were all associated with shorter TTR (supplementary Data S2, available at Annals of Oncology online). In multivariate analysis including all significant variables, KRAS mutations (P < 0.001), high-grade tumors (P = 0.012), pT4 (P = 0.009) and pN2 (P < 0.001) remained associated with shorter TTR (Table 2). Similar results were obtained for DFS (supplementary Data S3–S5, available at Annals of Oncology online).
original articles
Annals of Oncology
A
Proximal 12% 8%
1%
54%
17%
5% 3%
Wild-type Codon 12 Codon 13
C
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
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NS Wild-type Codon 12 Codon 13
WT G12A G12C G12D G12S G12R G12V G13D
6% 8%
Years
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
66%
P < 0.001 Wild-type Codon 12 Codon 13
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1
2
3
4
5
6
7
0
1
2
3
4
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7
316 201 69
282 168 62
209 145 46
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54 41 18
2 2 1
0 0 0
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641 242 59
476 198 51
334 175 39
128 72 14
3 2 0
0 0 0
0 0 0
Codon 12 p.G12A p.G12C p.G12D p.G12S p.G12R p.G12V Codon 13
Codon 12 p.G12A p.G12C p.G12D p.G12S p.G12R p.G12V Codon 13 2
4 6 8 12 18
0.1
1
10
Figure 3. Time to recurrence according to KRAS status for proximal and distal colon cancers. (A) KRAS mutation types in the PETACC8 trial population. (B) In proximal tumors, KRAS mutation status had no impact on time to recurrence (P = 0.69) whereas KRAS codon 12 mutations were associated with TTR in distal cancers (P < 0.001), and a trend was observed for codon 13 (P = 0.051). The individual impact of mutations is shown on figure (C) for proximal and distal cancers.
example, no association between KRAS mutations and relapse or survival was found in the PETACC-3 trial among 1404 CRC patients treated with 5-FU +/− irinotecan [12]. In contrast, the Quasar study [20], which mainly included stage II patients, showed an increased risk of recurrence among KRAS-mutated patients, which was not affected by adjuvant chemotherapy. The RASCAL population-based studies [13, 14] showed that KRAS p.G12V only, was associated with poorer outcome and Imamura et al. found that codon 12 but not codon 13 (HR 1.25; 95% CI 0.85–1.84; NS) mutations negatively affected cancer specific mortality [11]. In contrast, data from the NCCTG NO147 trial, which had a similar design to PETACC-08, showed that KRAS mutations at codons 12 (HR 1.52; 95% CI 1.28–1.8; P < 0.0001) and codon 13 (HR 1.36, 95% CI 1.04–1.72; P = 0.025) had a prognostic value [21, 22]. This may be due to the heterogeneity of the study populations, which included colon and rectal cancer, stage I–III tumors, patients receiving or not adjuvant treatments, patients with and without BRAF mutations and data from population-based cohorts or from clinical trials. In PETACC8 patients (n = 1657), KRAS codon 12 mutations were related to shorter TTR and DFS. Subsequently, we studied the impact of KRAS mutations on TTR and DFS according to
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tumor location [23]. Proximal tumors were more frequently KRAS-mutated than were distal tumors. Previous studies also reported higher KRAS mutation rates in proximal when compared with distal colon cancer [12, 23], but the relationship between cancer location, KRAS status and outcome remains unclear [23–25]. Here, no effect of KRAS mutations was found for proximal tumors. In contrast, codon 12 alterations had a negative impact on TTR in patients with distal tumors and although the test did not reach statistical significance for p.G13D (P = 0.051), there was a clear trend for a similar effect. This borderline significance is possibly due to the poor number of events and patients in this subgroup. Larger series are needed to definitely state on the prognostic impact of p.G13D in colon tumors. One limitation of our study is that MMR status was not available for patients enrolled in the PETACC8 trial. Deficient MMR phenotype tumors are mainly located in the proximal colon, associated with low recurrence rates, BRAF mutations and KRAS p.G13D [26–28]. We estimated that more than 50% of MSI-H cancers (10–15% of CCR) were excluded through the exclusion of BRAF-mutated cancers that tends to limit the possible confounding role of MSI status in our series and suggests that our results, by approximation refer to an MSS population.
doi:10.1093/annonc/mdu464 |
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Time to recurrence
B
1% 2%
Time to recurrence
0%
Distal WT G12A G12C G12D G12S G12R G12V G13D
original articles
acknowledgements We thank J. F. Côté for his skillful expertise in reviewing and selecting tumor samples for molecular analysis and T. Kombi for her technical assistance. We thank all PETACC-8 study investigators.
funding The study was sponsored by the Fédération Francophone de Cancérologie Digestive (FFCD) that was responsible for the study management. Merck KGaA and Sanofi-Aventis supported the study: Merck provided the study cetuximab and financial support for study management; Sanofi-Aventis provided financial support for the provision of oxaliplatin to Belgian sites when necessary. JT had full access to the data and had final responsibility for the decision to submit for publication.
disclosure JT received honoraria from Sanofi and Merck KGaA. J-FE received honoraria from Merck Serono. JT received honoraria from Amgen, Merck KGaA and Sanofi. GF declared research funding from Merck KGaA and honoraria from Merck KGaA, Roche, Lilly, BMS and Amgen; JT declared research funding and honoraria from Sanofi and Merck; JB declared advisory roles for Merck, Sanofi and Roche; LNP declared advisory roles for Roche and Bayer; EVC declared receiving research funding from Merck Serono paid to his institution. RS declared advisory roles and lectures for Merck KGaA and Amgen. PL-P declared providing advisory roles and lectures for Sanofi, Merck Serono, Amgen, Roche, Genomic Health, Myriad Genetics, and Pfizer. All remaining authors have declared no conflicts of interest.
references 1. Boyle P, Langman JS. ABC of colorectal cancer: epidemiology. BMJ 2000; 321 (7264): 805–808. 2. Jemal A, Siegel R, Ward E et al. Cancer statistics, 2008. CA Cancer J Clin 2008; 58(2): 71–96. 3. Andre T, Boni C, Navarro M et al. Improved overall survival with oxaliplatin, fluorouracil, and leucovorin as adjuvant treatment in stage II or III colon cancer in the MOSAIC trial. J Clin Oncol 2009; 27(19):3109–3116.
| Blons et al.
4. Karapetis CS, Khambata-Ford S, Jonker DJ et al. K-ras mutations and benefit from cetuximab in advanced colorectal cancer. N Engl J Med 2008; 359(17): 1757–1765. 5. Vogelstein B, Fearon ER, Hamilton SR et al. Genetic alterations during colorectaltumor development. N Engl J Med 1988; 319(9): 525–532. 6. Forbes SA, Bindal N, Bamford S et al. COSMIC: mining complete cancer genomes in the Catalogue of Somatic Mutations in Cancer. Nucleic Acids Res 2011; 39 (Database issue): D945–D950. 7. Bokemeyer C, Bondarenko I, Hartmann JT et al. Efficacy according to biomarker status of cetuximab plus FOLFOX-4 as first-line treatment for metastatic colorectal cancer: the OPUS study. Ann Oncol 2011; 22(7): 1535–1546. 8. Lievre A, Bachet JB, Boige V et al. KRAS mutations as an independent prognostic factor in patients with advanced colorectal cancer treated with cetuximab. J Clin Oncol 2008; 26(3): 374–379. 9. Van Cutsem E, Kohne CH, Hitre E et al. Cetuximab and chemotherapy as initial treatment for metastatic colorectal cancer. N Engl J Med 2009; 360(14): 1408–1417. 10. Gavin PG, Colangelo LH, Fumagalli D et al. Mutation profiling and microsatellite instability in stage II and III colon cancer: an assessment of their prognostic and oxaliplatin predictive value. Clin Cancer Res 2012; 18(23): 6531–6541. 11. Imamura Y, Morikawa T, Liao X et al. Specific mutations in KRAS codons 12 and 13, and patient prognosis in 1075 BRAF wild-type colorectal cancers. Clin Cancer Res 2012; 18(17): 4753–4763. 12. Roth AD, Tejpar S, Delorenzi M et al. Prognostic role of KRAS and BRAF in stage II and III resected colon cancer: results of the translational study on the PETACC-3, EORTC 40993, SAKK 60–00 trial. J Clin Oncol 2010; 28(3): 466–474. 13. Andreyev HJ, Norman AR, Cunningham D et al. Kirsten ras mutations in patients with colorectal cancer: the ‘RASCAL II’ study. Br J Cancer 2001; 85(5): 692–696. 14. Andreyev HJ, Norman AR, Cunningham D et al. Kirsten ras mutations in patients with colorectal cancer: the multicenter ‘RASCAL’ study. J Natl Cancer Inst 1998; 90(9): 675–684. 15. Morikawa T, Kuchiba A, Qian ZR et al. Prognostic significance and molecular associations of tumor growth pattern in colorectal cancer. Ann Surg Oncol 2012; 19(6): 1944–1953. 16. Taieb J, Tabernero J, Mini E et al. Oxaliplatin, fluorouracil, and leucovorin with or without cetuximab in patients with resected stage III colon cancer (PETACC-8): an open-label, randomised phase 3 trial. Lancet Oncol 2014; 15(8): 862–873. 17. Blons H, Rouleau E, Charrier N et al. Performance and cost efficiency of KRAS mutation testing for metastatic colorectal cancer in routine diagnosis: the MOKAECM study, a nationwide experience. PLoS One 2013; 8(7): e68945. 18. Farina-Sarasqueta A, van Lijnschoten G, Moerland E et al. The BRAF V600E mutation is an independent prognostic factor for survival in stage II and stage III colon cancer patients. Ann Oncol 2010; 21(12): 2396–2402. 19. Yokota T. Are KRAS/BRAF mutations potent prognostic and/or predictive biomarkers in colorectal cancers? Anticancer Agents Med Chem 2011; 12(2): 163–171. 20. Hutchins G, Southward K, Handley K et al. Value of mismatch repair, KRAS, and BRAF mutations in predicting recurrence and benefits from chemotherapy in colorectal cancer. J Clin Oncol 2011; 29(10): 1261–1270. 21. Yoon H, Tougeron D, Mahoney M et al. Prognostic impact of specific KRAS mutations in codon 12 and 13 in 2,165 BRAF-wildtype colon cancers: results from NCCTG N0147 (Alliance). Eur J Cancer 2013; 49: S484. 22. Yoon HH, Tougeron D, Shi Q et al. KRAS codon 12 and 13 mutations in relation to disease-free survival in BRAF-wild-type stage III colon cancers from an adjuvant chemotherapy trial (N0147 alliance). Clin Cancer Res 2014; 20(11): 3033–3043. 23. Benedix F, Meyer F, Kube R et al. Influence of anatomical subsite on the incidence of microsatellite instability, and KRAS and BRAF mutation rates in patients with colon carcinoma. Pathol Res Pract 2012; 208(10): 592–597. 24. Hansen IO, Jess P. Possible better long-term survival in left versus right-sided colon cancer—a systematic review. Dan Med J 2012; 59(6): A4444. 25. Weiss JM, Pfau PR, O’Connor ES et al. Mortality by stage for right- versus leftsided colon cancer: analysis of surveillance, epidemiology, and end results— Medicare data. J Clin Oncol 2011; 29(33): 4401–4409.
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Another limitation is the lack of data on rare KRAS and NRAS mutations. In a small cohort of patients, KRAS exon3/4- and NRAS-mutated tumors were associated to a better prognostic when compared with exon 2 alterations [29] but large prospective series are still needed to validate the prognostic impact of rare KRAS an NRAS alterations in CCR. In conclusion, we show in a series of stage III CCR patients included in a randomized, controlled phase III trial that codon 12 KRAS mutations have a significant impact on the TTR in distal CRC. The impact of the p.G13D mutation needs to be refined in a larger series according to tumor location and tumor phenotype (MSS/MSI) although this study suggests that p.G13D distal CRC might behave as p.G12X tumors. Future clinical trials in stage III colon cancer should consider both the tumor location and KRAS mutational status as important stratification factors.
Annals of Oncology
original articles
Annals of Oncology 26. Oliveira C, Westra JL, Arango D et al. Distinct patterns of KRAS mutations in colorectal carcinomas according to germline mismatch repair defects and hMLH1 methylation status. Hum Mol Genet 2004; 13(19): 2303–2311. 27. Phipps AI, Buchanan DD, Makar KW et al. BRAF mutation status and survival after colorectal cancer diagnosis according to patient and tumor characteristics. Cancer Epidemiol Biomarkers Prev 2012; 21(10): 1792–1798.
28. Phipps AI, Buchanan DD, Makar KW et al. KRAS-mutation status in relation to colorectal cancer survival: the joint impact of correlated tumour markers. Br J Cancer 2013; 108(8): 1757–1764. 29. Janakiraman M, Vakiani E, Zeng Z et al. Genomic and biological characterization of exon 4 KRAS mutations in human cancer. Cancer Res 2010; 70(14): 5901–5911.
Annals of Oncology 25: 2385–2391, 2014 doi:10.1093/annonc/mdu463 Published online 3 October 2014
Q. Zhou1, Y. Cheng2, J.-J. Yang1, M.-F. Zhao3, L. Zhang4, X.-C. Zhang1, Z.-H. Chen1, H.-H. Yan1, Y. Song5, J.-H. Chen6, W.-N. Feng7, C.-R. Xu1, Z. Wang1, H.-J. Chen1, W.-Z. Zhong1, Y.-P. Liu3 & Y.-L. Wu1* 1
Department of Pulmonary Oncology, Guangdong Lung Cancer Institute, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou; Department of Pulmonary Oncology, Jilin Provincial Cancer Hospital, Changchun; 3Department of Medical Oncology, The First Hospital of China Medical University, Shenyang; 4Department of Respiratory Medicine, Perking Union Medical Hospital, Beijing; 5Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing; 6Department of Medical Oncology, Hunan Cancer Hospital, Changsha; 7Department of Medical Oncology, The First People’s Hospital of Foshan, Foshan, China 2
Received 30 May 2014; revised 1 September 2014 and 23 September 2014; accepted 23 September 2014
Background: CTONG0806 assessed the efficacy of pemetrexed versus gefitinib as second-line treatment in advanced nonsquamous nonsmall-cell lung cancer (NSCLC) harboring wild-type epidermal growth factor receptor (EGFR). Patients and methods: Patients with locally advanced or metastatic nonsquamous NSCLC harboring wild-type EGFR, detected by direct sequencing, and previously treated with platinum-based chemotherapy were randomized to receive gefitinib (250 mg/day) orally or pemetrexed (500 mg/m2) i.v. on day 1 of a 21-day cycle until disease progression or unacceptable toxicity. The primary end point was progression-free survival (PFS). The Independent Review Committee (IRC) evaluated all pictorial data. Results: From February 2009 to August 2012, 161 patients were enrolled, and 157 were assessable (81 in the gefitinib arm, 76 in the pemetrexed arm). Baseline characteristics were balanced between the two arms. The median PFSs were 4.8 versus 1.6 months in the pemetrexed and gefitinib arms, respectively [hazard ratio (HR) 0.54, 95% confidence interval (CI) 0.40–0.75, P < 0.001] as confirmed by IRC evaluation (5.6versus 1.7 months, HR 0.53, 95% CI 0.38–0.75, P < 0.001). The median overall survival (OS) showed a trend of superiority in the pemetrexed arm (12.4 versus 9.6 months, HR 0.72, 95% CI 0.49–1.04, P = 0.077). Quality-of-life assessment showed no marked difference between the arms. No unexpected adverse events were found. Of 108 patients with sufficient DNA samples, EGFR mutation status was re-tested by Scorpion amplification refractory mutation system (ARMS); 32 (29.6%) tested positive (19 in the pemetrexed arm, 13 in the gefitinib arm; median PFS: 8.1 versus 7.0 months, HR 0.94, 95% CI 0.43–2.08, P = 0.877). *Correspondence to: Dr Yi-Long Wu, Guangdong Lung Cancer Institute, Guangdong General Hospital and Guangdong Academy of Medical Sciences, 106 Zhongshan Er Road, Guangzhou 510080, China. Tel: +86-20-83877855; Fax: +86-20-83827712; E-mail: [email protected] †
Data from this study were previously accepted for oral presentation at the 15th World Conference on Lung Cancer (WCLC), Sydney, Australia, 28–30 September 2013, and was selected to be released in press conference during this WCLC.
© The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: [email protected].
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Pemetrexed versus gefitinib as a second-line treatment in advanced nonsquamous nonsmall-cell lung cancer patients harboring wild-type EGFR (CTONG0806): a multicenter randomized trial†