OBJECTIVETo explore the possibility of further improvement of the efficacy of neoadjuvant chemoradiotherapy in locally advanced lower rectal cancer and the management of patients with clinical complete regression.

METHODSFrom May 2001 to August 2007, 192 cases with locally advanced lower rectal cancer (T3/T4 or N(+)) received preoperative radiotherapy 40 - 46 Gy/20 - 23 fractions and concomitant oral capecitabine 625 mg/m(2) bid for 10 weeks prior to surgery. Curative resection with total mesorectal excision (TME) was carried out 6 weeks after the end of radiation.

RESULTSAs a result, 117 cases (60.9%) experienced adverse events but only 2 suffered from G3 side effects. Seventeen cases (8.9%) had a clinical complete tumor regression without surgery; 175 patients underwent curative resection, of them 134 cases with low anterior resection (LAR), 32 cases with ultra-low anterior resection with Park's coloanal anastomosis (6 cases with diverting temporary colostomy) and 9 cases with abdominal pelvic resection (APR). Sphincter preservation was achieved in 94.9%. Twenty-four patients (12.5%) got pathological complete response (CR), 17 patients with clinical CR and the overall CR rate was 21.4%. According to the pathological staging post operation: T0N0 41 cases, T2N0 43 cases, T3N0 77 cases, T4N0 5 cases, T2N1 11 cases, T3N1 13 cases, T4N1 2 cases; Graded under Dworak's tumor regression: TRG0 8 patients, TRG1 32 patients, TRG2 28 patients, TRG3 83 patients and TRG4 24 patients, with an overall pathological tumor downstaging in 77.14%. No operative death occurred, 5 patients suffered from rectovaginal fistulas and 4 anastomotic leakages with an overall anastomotic leakage rate of 5.1% (9/175) and all the patients recovered uneventfully after properly managed. All patients were followed up for a median time of 42 months (range, 12 - 87 months). During the time, 11 patients developed lung metastases, 6 liver metastases and 7 had local recurrences. The 3 years disease-free survival (DFS) was 86.6% and overall survival (OS) was 92.6%.

CONCLUSIONSNeoadjuvant chemoradiotherapy has high efficacy in locally advanced lower rectal cancer, resulting in tumor down-staging, improved resectability and sphincter preservation, and reduced local recurrences. Meanwhile the cases with clinical complete response can be followed up closely and safely without surgery.