- Email: [email protected]
Rotational Intensity Modulated Radiation Therapy in Complex Adjuvant Breast and Nodes Irradiation
Volume 93 Number 3S Supplement 2015
Poster Viewing Session
pZ.028), receive chemotherapy (84% vs. 67%, p<.001), and receive Herceptin (39% vs. 23%, pZ.005). The 7-year LRR-free survival for the entire cohort was 92.4% (95% CI 88.7-94.9). EIC+ patients had a significantly higher 7-year LRR rate (14.7% vs. 5.2%, pZ.019), as did younger (age 50) patients (14.1% vs. 3.7%, p<.001). After adjustment for age, chemotherapy receipt, and Herceptin receipt, the presence of EIC remained significant for increased LRR (HR 2.34; 95% CI 1.08-5.06; pZ.031). Conclusion: EIC was a prominent pathologic feature seen in 24% of patients with HER2+ breast cancer treated with breast conserving therapy. Despite the achievement of negative surgical margins in the vast majority of patients, EIC was prognostic for LRR. These results must be confirmed in larger cohorts of HER2+ patients treated with anti-HER2 therapies. Author Disclosure: N. Ohri: None. C.T. Siu: None. A. Eaton: None. A.Y. Ho: None.
2085 Rotational Intensity Modulated Radiation Therapy in Complex Adjuvant Breast and Nodes Irradiation O. Lauche,1 Y.M. Kirova,2 P.J. Fenoglietto,1 C. Bourgier,1 C. Lemanski,1 F. Campana,2 E. Costa,2 A. Fourquet,3 and D. Azria1; 1Institut du Cancer de Montpellier, Montpellier, France, 2Institut Curie, Paris, France, 3Institut Curie, Paris 75005, France Purpose/Objective(s): Analyze clinical and dosimetric results of helical tomotherapy (HT) and rapid arc (RA) in complex adjuvant breast and nodes (IMC and supraclavicular nodes) irradiation with simultaneous-integrated boost Materials/Methods: Seventy-three patients were included in the study (31 HT and 42 RA). Treatments were in 29 fractions. Dose prescriptions were 63.8 Gy (HT) and 63.2 Gy (RA) in the tumor bed, 52.2 Gy in the breast (HT and RA), 50.4 Gy in supraclavicular nodes and IMC with HT and 52.2 Gy, and 49.3 Gy in IMC and supraclavicular nodes with RA. Margins to the PTV were greater in the RA cohort (7mm vs 5mm Results: Doses to heart and lung are summarized in the table below:
Poster Viewing Abstracts 2085; Table 1 Organs at risk Ipsilateral lung
Heart
RA V5 V20 V30 Dmean V5 V30 Dmean
85,3% 20,1% 8,8% 13,6 Gy 77,6% 2,5% 10,3 Gy
HT 9,6 3,2 3,2 1,4 21 3,8 4,2
77,6% 20,9% 10% 13,4 Gy 58,5% 1% 7,4 Gy
12 5 3 2 15 1 1,4
For contralateral breast, mean dose (Dmean) and V5 were respectively 3.6 Gy 0.7 and 15% 7.8 for HT and 4.6 Gy 0.9 and 32% 11.9 for RA. For esophagus, V40 and V5 were respectively 1.8 mm3 1.8 and 18.4 mm3 9.7 for HT and 0.9 mm3 1 and 14.1 mm3 7.5 for RA. For thyroid, V30 and V5 were 39.7% 16.9 and 95% 12.7 for HT and 44% 15.3 and 97.1% 8.3 for RA. For Healthy tissue, V40 and V5 were 1804 mm3 745 and 8333 mm3 1950 for HT and 1977 mm3 911 and 9770 mm3 2551 for RA. There were 5% of acute skin toxicity grade 3 in the two cohorts, 35% of esophageal toxicity grade 2 in the HT cohort, and 40% in the RA cohort and no acute lung or heart toxicity. Conclusion: Rotational IMRT is associated with low acute toxicities and reduced high dose volume to organs at risk in cases of complex anatomy. As low dose distribution after rotational IMRT is large, a careful follow-up regarding healthy tissues is warranted. Since uncertainties still remain regarding the impact of low dose, this technique should only be considered to a selected population of breast cancer with complex anatomy. Author Disclosure: O. Lauche: None. Y.M. Kirova: None. P.J. Fenoglietto: None. C. Bourgier: None. C. Lemanski: None. F. Campana: None. E. Costa: None. A. Fourquet: None. D. Azria: None.
E35
2086 Supraclavicular Nodal Involvement in Breast Cancer: How and When Should We Adapt the RTOG Atlas Guidelines? S.A. Dudley, Y. Qian, and K.C. Horst; Department of Radiation Oncology, Stanford Cancer Institute, Stanford, CA Purpose/Objective(s): The role of regional nodal irradiation (RNI) in breast cancer is evolving. In the current era of 3D treatment planning, it is important to accurately identify target volumes. The Radiation Therapy Oncology Group (RTOG) has outlined guidelines to define target nodal volumes for early stage breast cancer. The aim of this study was to identify whether breast cancer nodal involvement in the supraclavicular region correlated with the clinical tumor volume (CTV) as defined by the RTOG atlas. Materials/Methods: Thirty-one women with invasive breast carcinoma with supraclavicular nodal involvement were identified for analysis. For each patient, an individual CTV for the supraclavicular nodal region was contoured using the RTOG Breast Cancer Contouring Atlas as a guide. Involved nodes (gross tumor volume, GTV) were contoured independently using information from diagnostic imaging (including computed tomography (CT), positron emission tomography (PET)/CT, or magnetic resonance imaging (MRI). The supraclavicular CTV was compared to the GTVs for pathologic nodes, and each node was assigned a value for complete coverage, partial coverage, or complete discordance. In cases of partial coverage, the degree of coverage was expressed a percentage of the volume of the node which fell within the supraclavicular CTV. Results: Forty-nine supraclavicular lymph nodes were available for comparison to the supraclavicular CTV. 36.7% of the nodes were completely concordant, while 10.2% were completely discordant. For the remaining 53.1% of supraclavicular nodes which were partially covered, the degree of coverage ranged from 4.2% to 96.7%. In the cases where there was discordance, the nodes were located posteriorly and/or laterally to the supraclavicular CTV. Patients with supraclavicular nodal involvement were more likely to have adverse pathologic features, with 13 of 31 (42%) having estrogen/progesterone/Her2-neu negative cancer (triple negative) and 14 of 31 (45%) having estrogen receptor positive tumors with high Ki-67 or Her2-neu positivity (consistent with a luminal B-like tumor). Conclusion: Understanding patterns of supraclavicular nodal failure in breast cancer could help guide prophylactic nodal irradiation, and this study suggests that current RTOG atlas guidelines for the supraclavicular fossa may not extend posteriorly and laterally enough. However, given that broadening coverage may result in increased toxicity, identifying subsets of women at higher risk for failure is of particular importance. Author Disclosure: S.A. Dudley: None. Y. Qian: None. K.C. Horst: None.
2087 Noninvasive Breast Brachytherapy Boost: Cosmesis and Tumor Control J.M. Schuster,1 C. Chipko,2 C.A. Quiet,3 R.K. Benda,4 S.J. Sha,5 A.M. Kuruvilla,6 C.S. Anderson,7 K.L. Leonard,8 D.E. Wazer,9 J.T. Hepel,9 and D.W. Arthur2; 1Virginia Commonwealth University Medical Center, Richmond, VA, 2Virginia Commonwealth University, Richmond, VA, 3Arizona Breast Cancer Specialists, Arizona Center for Cancer Care, Phoenix, AZ, 4Lynn Cancer Institute, Boca Raton, FL, 5 Central Florida Cancer Institute, Davenport, FL, 6First Radiation and Oncology Group, Palatka, FL, 7Florida Radiation Oncology Group LLC, Jacksonville, FL, 8Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI, 9 Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI Purpose/Objective(s): To evaluate cosmesis and tumor control results after high dose rate (HDR) noninvasive breast brachytherapy (NIBB) for tumor bed boost in combination with whole breast radiation therapy
Poster Viewing Session
pZ.028), receive chemotherapy (84% vs. 67%, p<.001), and receive Herceptin (39% vs. 23%, pZ.005). The 7-year LRR-free survival for the entire cohort was 92.4% (95% CI 88.7-94.9). EIC+ patients had a significantly higher 7-year LRR rate (14.7% vs. 5.2%, pZ.019), as did younger (age 50) patients (14.1% vs. 3.7%, p<.001). After adjustment for age, chemotherapy receipt, and Herceptin receipt, the presence of EIC remained significant for increased LRR (HR 2.34; 95% CI 1.08-5.06; pZ.031). Conclusion: EIC was a prominent pathologic feature seen in 24% of patients with HER2+ breast cancer treated with breast conserving therapy. Despite the achievement of negative surgical margins in the vast majority of patients, EIC was prognostic for LRR. These results must be confirmed in larger cohorts of HER2+ patients treated with anti-HER2 therapies. Author Disclosure: N. Ohri: None. C.T. Siu: None. A. Eaton: None. A.Y. Ho: None.
2085 Rotational Intensity Modulated Radiation Therapy in Complex Adjuvant Breast and Nodes Irradiation O. Lauche,1 Y.M. Kirova,2 P.J. Fenoglietto,1 C. Bourgier,1 C. Lemanski,1 F. Campana,2 E. Costa,2 A. Fourquet,3 and D. Azria1; 1Institut du Cancer de Montpellier, Montpellier, France, 2Institut Curie, Paris, France, 3Institut Curie, Paris 75005, France Purpose/Objective(s): Analyze clinical and dosimetric results of helical tomotherapy (HT) and rapid arc (RA) in complex adjuvant breast and nodes (IMC and supraclavicular nodes) irradiation with simultaneous-integrated boost Materials/Methods: Seventy-three patients were included in the study (31 HT and 42 RA). Treatments were in 29 fractions. Dose prescriptions were 63.8 Gy (HT) and 63.2 Gy (RA) in the tumor bed, 52.2 Gy in the breast (HT and RA), 50.4 Gy in supraclavicular nodes and IMC with HT and 52.2 Gy, and 49.3 Gy in IMC and supraclavicular nodes with RA. Margins to the PTV were greater in the RA cohort (7mm vs 5mm Results: Doses to heart and lung are summarized in the table below:
Poster Viewing Abstracts 2085; Table 1 Organs at risk Ipsilateral lung
Heart
RA V5 V20 V30 Dmean V5 V30 Dmean
85,3% 20,1% 8,8% 13,6 Gy 77,6% 2,5% 10,3 Gy
HT 9,6 3,2 3,2 1,4 21 3,8 4,2
77,6% 20,9% 10% 13,4 Gy 58,5% 1% 7,4 Gy
12 5 3 2 15 1 1,4
For contralateral breast, mean dose (Dmean) and V5 were respectively 3.6 Gy 0.7 and 15% 7.8 for HT and 4.6 Gy 0.9 and 32% 11.9 for RA. For esophagus, V40 and V5 were respectively 1.8 mm3 1.8 and 18.4 mm3 9.7 for HT and 0.9 mm3 1 and 14.1 mm3 7.5 for RA. For thyroid, V30 and V5 were 39.7% 16.9 and 95% 12.7 for HT and 44% 15.3 and 97.1% 8.3 for RA. For Healthy tissue, V40 and V5 were 1804 mm3 745 and 8333 mm3 1950 for HT and 1977 mm3 911 and 9770 mm3 2551 for RA. There were 5% of acute skin toxicity grade 3 in the two cohorts, 35% of esophageal toxicity grade 2 in the HT cohort, and 40% in the RA cohort and no acute lung or heart toxicity. Conclusion: Rotational IMRT is associated with low acute toxicities and reduced high dose volume to organs at risk in cases of complex anatomy. As low dose distribution after rotational IMRT is large, a careful follow-up regarding healthy tissues is warranted. Since uncertainties still remain regarding the impact of low dose, this technique should only be considered to a selected population of breast cancer with complex anatomy. Author Disclosure: O. Lauche: None. Y.M. Kirova: None. P.J. Fenoglietto: None. C. Bourgier: None. C. Lemanski: None. F. Campana: None. E. Costa: None. A. Fourquet: None. D. Azria: None.
E35
2086 Supraclavicular Nodal Involvement in Breast Cancer: How and When Should We Adapt the RTOG Atlas Guidelines? S.A. Dudley, Y. Qian, and K.C. Horst; Department of Radiation Oncology, Stanford Cancer Institute, Stanford, CA Purpose/Objective(s): The role of regional nodal irradiation (RNI) in breast cancer is evolving. In the current era of 3D treatment planning, it is important to accurately identify target volumes. The Radiation Therapy Oncology Group (RTOG) has outlined guidelines to define target nodal volumes for early stage breast cancer. The aim of this study was to identify whether breast cancer nodal involvement in the supraclavicular region correlated with the clinical tumor volume (CTV) as defined by the RTOG atlas. Materials/Methods: Thirty-one women with invasive breast carcinoma with supraclavicular nodal involvement were identified for analysis. For each patient, an individual CTV for the supraclavicular nodal region was contoured using the RTOG Breast Cancer Contouring Atlas as a guide. Involved nodes (gross tumor volume, GTV) were contoured independently using information from diagnostic imaging (including computed tomography (CT), positron emission tomography (PET)/CT, or magnetic resonance imaging (MRI). The supraclavicular CTV was compared to the GTVs for pathologic nodes, and each node was assigned a value for complete coverage, partial coverage, or complete discordance. In cases of partial coverage, the degree of coverage was expressed a percentage of the volume of the node which fell within the supraclavicular CTV. Results: Forty-nine supraclavicular lymph nodes were available for comparison to the supraclavicular CTV. 36.7% of the nodes were completely concordant, while 10.2% were completely discordant. For the remaining 53.1% of supraclavicular nodes which were partially covered, the degree of coverage ranged from 4.2% to 96.7%. In the cases where there was discordance, the nodes were located posteriorly and/or laterally to the supraclavicular CTV. Patients with supraclavicular nodal involvement were more likely to have adverse pathologic features, with 13 of 31 (42%) having estrogen/progesterone/Her2-neu negative cancer (triple negative) and 14 of 31 (45%) having estrogen receptor positive tumors with high Ki-67 or Her2-neu positivity (consistent with a luminal B-like tumor). Conclusion: Understanding patterns of supraclavicular nodal failure in breast cancer could help guide prophylactic nodal irradiation, and this study suggests that current RTOG atlas guidelines for the supraclavicular fossa may not extend posteriorly and laterally enough. However, given that broadening coverage may result in increased toxicity, identifying subsets of women at higher risk for failure is of particular importance. Author Disclosure: S.A. Dudley: None. Y. Qian: None. K.C. Horst: None.
2087 Noninvasive Breast Brachytherapy Boost: Cosmesis and Tumor Control J.M. Schuster,1 C. Chipko,2 C.A. Quiet,3 R.K. Benda,4 S.J. Sha,5 A.M. Kuruvilla,6 C.S. Anderson,7 K.L. Leonard,8 D.E. Wazer,9 J.T. Hepel,9 and D.W. Arthur2; 1Virginia Commonwealth University Medical Center, Richmond, VA, 2Virginia Commonwealth University, Richmond, VA, 3Arizona Breast Cancer Specialists, Arizona Center for Cancer Care, Phoenix, AZ, 4Lynn Cancer Institute, Boca Raton, FL, 5 Central Florida Cancer Institute, Davenport, FL, 6First Radiation and Oncology Group, Palatka, FL, 7Florida Radiation Oncology Group LLC, Jacksonville, FL, 8Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI, 9 Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI Purpose/Objective(s): To evaluate cosmesis and tumor control results after high dose rate (HDR) noninvasive breast brachytherapy (NIBB) for tumor bed boost in combination with whole breast radiation therapy