435. Unfavorable Effect of Preoperative Chemotherapy for Initially Resectable Colorectal Liver Metastases

858 Results: The retrohepatic process of the Spieghel lobe extended most dorsal at 22% of distance and was most close to the right dorsal liver at 25% of distance from the top of the retrohepatic IVC. In 11 (22%) patients, the retrocaval portion of the Spieghel lobe projected right dorsally, while the right dorsal liver extended left dorsally in one patient. And in nine patients (18%), the retrohepatic process appeared connected with the right dorsal liver. An 80-year-old man with 8cm metastatic colon cancer occupying the whole Spieghel lobe and tucking around the IVC underwent extended left hemihepatectomy with semicircle resection and patch reconstruction of the IVC, using this approach. Conclusions: The Spieghel lobe sometimes extends around to the right dorsal aspect of the IVC, thus right side approach will give a good surgical field and feasibility for securing the retrohepatic IVC through the lesser sac and dissecting a protruding portion of the tumor. 434. Kruppel like Factor 6 Splice Variant 1 in Patients with Colorectal Liver Metastasis Correlates with a Higher Prognostic Scores K.Y.D. Hui1, S. Robinson2, G.L. Patman1, D. Manas2, H. Reeves1, S.A. White2 1 Newcastle University, Northern Institute for Cancer Research, Newcastleupon-Tyne, United Kingdom 2 The Freeman Hospital, Department of HPB and Transplant Surgery, Newcastle-upon-Tyne, United Kingdom Introduction: In its wild type form KLF6 (KLF6-WT) acts as a tumour suppressor gene whose expression is lost in a variety of human cancers. Conversely, KLF-6 splice variant 1 (KLF6-SV1) is able to function as an oncogene playing an important role in tumour proliferation and invasion. The aim of this study was to determine how the expression of these two KLF6 variants in patients with colorectal liver metastases (CRLM) correlates with two established prognostic scoring systems. Methods: Patients undergoing resection of CRLM over a 2 year period were identified for inclusion within this study. Immunohistochemistry was performed using antibodies directed against KLF6-WT and KLF6-SV1 on formalin fixed paraffin embedded tumour samples and the proportion of positively stained nuclei for each was determined using an automated computerized image analysis system (APERIO). Clinical data was collected and prognostic scores from Fong and Nagashima were calculated as a marker of patients’ outcome. Spearmans correlation coefficient was used to determine the relationship between nuclear staining of KLF-6 and the CRS. Continuous variables were compared with Mann Whitney U Test. A p-value <0.05 was considered significant. Results: Twenty five patients (male 64%) were included in this study with a mean age of 69.2 years (range 52-81).The distribution of prognostic scores were as follows; Fong score 0 n¼2, Fong score 1 n¼6, Fong score 2 n¼ 3, Fong score 3 n¼10, Fong score 4 n¼3, Fong score 5 n¼1; Nagashima score 1 n¼5, Nagashima score 2 n¼ 4, Nagashima score 3 n¼9, Nagashima score 4 n¼7. 9 patients developed recurrence within 1 year of liver resection. All patients remained alive at the end of the study period. There were positive correlation between KLF6-SV1 and the calculated Fong score and Nagashima score (Spearman’s correlation efficient ¼ 0.481, p¼0.015 and Spearman’s correlation efficient ¼ 0.445, p¼0.026, respectively) whereas no such correlation existed with KLF6-WT. In those with a Fong score <3 the mean proportion of positive nuclear staining for KLF6-SV1 was 5% compared to 15% in those with a Fong score3 (p<0.05). Conclusion: In this preliminary study, high expression of KLF6-SV1 in patients with CRLM correlates with higher prognostic scores. Further long-term follow up data is required to determine what effect this has on prognosis and overall patient survival. 435. Unfavorable Effect of Preoperative Chemotherapy for Initially Resectable Colorectal Liver Metastases R. Nishitai1, D. Manaka1, S. Hamasu1, S. Konishi1, K. Sakamoto1, K. Yoshino1, S. Kanto1, D. Yokoyama1, M. Uehara1 1 Kyoto-Katsura Hospical, Department of Surgery, Kyoto, Japan

ABSTRACTS Background: After the EORTC 40983 study, perioperative chemotherapy has been widely conducted against colorectal liver metastases (CRLM). However, since controversial result was reported in a large Cohort study (LiverMetSurvey), the role of preoperative chemotherapy for initially resectable CRLM seems to remain unclear. Therefore, we retrospectively examined the utility of preoperative chemotherapy for CRLM in our hospital. Materials and methods: Twenty cases of initially resectable CRLM (from 2006 to 2011) who received preoperative doublet chemotherapy which consisted of oxaliplatin or irrinotecan and fluorouracil (NAC group) and 43 cases of CRLM (from 2000 to 2011) who underwent hepatectomy without preoperative oxaliplatin or irrinotecan (SURG group) were evaluated. The demographic of the two groups were similar, and most of the patients received fluorouracil based postoperative chemotherapy (adjuvant chemotherapy). We compared disease free survival after hepatectomy (DFS) and overall survival between the two groups. Results: As for DFS, there was a tendency that NAC group showed shorter intervals than SURG group. The tendency became apparent 1 year after hepatectomy (p¼0.18). The overall survival curves of NAC and SURG group were completely overlapped, although the observation period was not long enough to evaluate statistical significance. This result might suggest that preoperative chemotherapy was not necessarily required for CRLM. For further investigation, according to age, synchronous metastases or metachronous, lymph node involvement of the primary, the number of the metastases, the size of the largest tumor, existence of extrahepatic metastases at the time of hepatectomy, carcinoembryonic antigen (CEA) or carbohydrate antigen 19-9 (CA19-9) levels before hepatectomy, surgical margin, we divided 63 cases into two subpopulations, and compared between DFS of NAC group and that of SURG group within each subpopulations. Among those subpopulations, DFS of NAC group was significantly shorter in the patients with less than 5 metastases, as compared to that of SURG group (p¼0.03). In addition, NAC group showed a tendency of shorter DFS than SURG group in 70 years of age or younger, metachronous metastases, maximum tumor size of 5 cm, no extrahepatic metastases, negative surgical margin. Conclusion: We observed that preoperative chemotherapy was not necessarily required for some low-risk subpopulations of CRLM patients. Uniform application of preoperative chemotherapy to low-risk initially-resectable CRLM should be reconsidered. In order to refine the indication, further evaluation of the relationship between the number of metastases and the prognostic effect of preoperative chemotherapy for resectable CRLM is required. 436. Benefit of Liver Resection for Selected Cases of Non-colorectal, Non-neuroendocrine Liver Metastases S. Schuele1, A. Altendorf-Hofmann1, Y. Dittmar1, T. Knoesel2, U. Settmacher1 1 Friedrich-Schiller-University Jena, Department of General Visceral and Vascular Surgery, Jena, Germany 2 Ludwig-Maximilians-University Munich, Institute of Pathology, Munich, Germany Introduction: Resection for colorectal or neuroendocrine liver metastases is an established therapeutical concept at present. Data for liver metastases originating from other primary tumours are less clear. We have reviewed the outcome of our patients after resection of non-colorectal, non-neuroendocrine liver metastases (NCNN) regarding prognostic factors and survival. Material and methods: Data of all patients treated in our Department for NCNN from 1995 to 2011 were extracted from our prospective cancer registry. Observed 5-year survival rates were calculated according to Kaplan-Meier and compared by log-rank test. Results: From 1995 to 2011, 199 patients with NCNN underwent laparotomy. In 105 cases, complete removal of the metastatic lesion was achieved with extrahepatic tumour resection in 22 cases (21%); 23 patients underwent radiofrequency ablation (RFA), 5 of them in palliative intent. Metastases occurred synchronously in almost one third of the patients. Median disease-free interval