OBJECTIVETo explore the efficacy prediction of the locally advanced rectal cancer patients, especially those with pathological complete response(pCR), receiving neoadjuvant chemoradiotherapy in order to execute precise preoperative neoadjuvant chemoradiotherapy.

METHODSFrom January 2000 to January 2011, 125 patients diagnosed as locally advanced rectal cancer receiving preoperative neoadjuvant chemoradiotherapy in our department with complete data were enrolled in this study, including 85 males and 40 females with mean age of 54(15 to 77) years old. All the patients received radiotherapy with 46 Gy(23 times) and administered XELOX regimen (oxaliplatin 100 mg/m(2) plus capecitabine 2 000 mg/m(2)) for 2 courses simultaneously, and underwent radical operation 6 to 8 weeks after chemoradiotherapy. The data of these patients were analyzed retrospectively. Pathological remission was divided into 4 grades. Patients achieving grade 4 were defined as pCR, and those achieving above grade 2 were defined as better response. Logistic regression analysis was used to identify significant predictors of pCR.

RESULTSAmong 125 patients, 16(12.8%) achieved pCR status, and 90(72.0%) had better response to the neoadjuvant chemoradiotherapy. Logistic regression analysis showed that age(OR:1.060, P=0.037) and preoperative positive lymph nodes detected by endorectal ultrasonography (OR:0.059, P=0.006) were independent predictors of pCR after neoadjuvant chemoradiotherapy.

CONCLUSIONSPreoperative existence of lymph node metastasis around bowel indicates the poor response to neoadjuvant chemoradiotherapy. Age is associated with pCR in patients receiving neoadjuvant chemoradiotherapy.