314. Preoperative Versus Postoperative Chemoradiotherapy for Locally Advanced Rectal Cancer

S 831 As a conclusion, the activity of cytokine reaction of advance CRC has the disorganization. The CRC with SCID has typical hyperactive TNF-a. If the patients of CRC haven~ Ot immunodeficiency they have hyperactive IL2 and IFN-g and hypoactive TNF-a. The different reaction of cytokines and indices of CR may be used for option of immune rehabilitation of advance CRC after complex treatment. 314. Preoperative Versus Postoperative Chemoradiotherapy for Locally Advanced Rectal Cancer J.S. Kim, S.Y. Jeong, R. Shin, H.K. Oh, K.J. Park, J.G. Park 1 Dongnam Institute of Radiological and Medical Sciences, Department of Surgery, Busan, Korea 2 Seoul National University Cancer Hospital Seoul National University College of Medicine, Colorectal Cancer Center Department of Surgery, Seoul, Korea 3 Seoul National University Cancer Hospital, Colorectal Cancer Center, Seoul, Korea Background: German trial demonstrated that preoperative chemoradiotherapy (CRT), as compared with postoperative CRT, improved local control and was associated with reduced toxicity. Since then, however, there has been no study on this issue. This study compared the surgical and oncologic outcomes between preoperative and postoperative CRT in patients with locally advanced rectal cancer. Material andmethods:Between January 2005 and December 2008, 196 patients who underwent curative intent surgery for locally advanced extraperitoneal rectal cancer (cT3/4NxM0) at the Seoul National University Hospital were analyzed. One hundred nineteen patients (preop group) received preoperative CRT (50.4 Gy with concurrent 5-fluorouracil or capecitabine) and 77 patients (postop group) received same dose postoperative CRTwith 5-fluorouracil or capecitabine with or without oxaliplatin. Total mesorectal excision was performed after an interval of 6-8 weeks.Whether to deliver CRT preoperatively or postoperatively was determined by surgeons~ O preferences. Results: The median follow-up time was 50.3 months. Patients~ O characteristics including age, sex, and clinical T and N categories were not different between the groups. Sphincter sparing rate in patients with tumor within 3cm from the anal verge was higher in preop group (92.3% vs. 50.0%, P1⁄40.024). And diversion rate was significantly higher in preop group (52.2% vs. 6.8%, p 27%) nuclear staining. P53 was scored in percentage positive nuclei and scores were divided in negative staining (0%), restricted overexpression (-25%) and overexpression (>25%). Caspase-3 was scored as absent, weak, moderate and strong cytoplasmatic staining. Finally, M30 was scored as presence versus absence. Results: Presence of Ki67 was significantly related to a better OS and DFS (p1⁄4 0.003, HR 0.656 and p1⁄40.007, HR 0.684 respectively). P53 was not related to clinical outcome. Interestingly, patients without p53 expression before chemotherapy showed a better OS (HR 5.2 in case of restricted overexpression and HR 4.7 for overexpression, p1⁄40.033) and DFS (HR 4.7 and 4.9 respectively, p1⁄4 0.037) M30 was related to a better DFS (p1⁄4 0.050) and borderline significant for OS (p1⁄40.062). Caspase-3 was not related to OS and DFS. Patients with presence of both Ki67 and M30 had a better OS and DFS (p1⁄40.002, HR 0.52 and p1⁄40.001, HR 0.51 resp.). The same was true for the combination Ki67 and Caspase-3 with HRs of 0.65 for OS (p1⁄4 0.028) and 0.69 (p1⁄40.054) for DFS. In multivariate analysis, Ki67 was an independent predictor for OS (p1⁄40.011) and DFS (p1⁄40.020). The combinations Ki67 with Caspase-3 and Ki67 with M30 were borderline independent predictors for OS (p1⁄40.056 and 0.060). For DFS, Ki67 with M30 was a borderline significant independent predictor. Conclusions: Ki67, independently and in combination with M30 or Caspase-3, is an important prognostic marker for CRC for both DFS and