Objective: To 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.
Methods: From 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.
Results: As 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%.
Conclusions: Neoadjuvant 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.