OBJECTIVETo evaluate the efficacy of preoperative radiochemotherapy and investigate the influencing factors in rectal cancer.

METHODSFifty-three patients with locally advanced rectal cancer were treated with radiochemotherapy before surgery. Three-field technique of radiation therapy was administered with 46 Gy, 2 Gy per fraction, five times a week. Two cycles of chemotherapy were carried out at day 1, 2 and day 21, 22 during the radiation course. Surgery was performed 4-6 weeks after the radiochemotherapy. Response of preoperative radiochemotherapy was evaluated in all the patients by endoscopic ultrasonography (EUS), spiral computed tomography (SCT) and pathology. Influencing factors of the efficacy of radiochemotherapy were evaluated by univariate and Logistic analysis.

RESULTSUnivariate analysis revealed that tumor size and histological grading were associated with the efficacy of preoperative radiochemotherapy. Logistic regression analysis showed that only tumor size was the significant predictive factor for response to preoperative radiochemotherapy. All patients underwent surgical resection after preoperative radiochemotherapy. The tumor was reduced by an average of 32.1%. T-level down-staging was 64.2%. Nodal negativity was 58.1%. Complete pathologic remission occurred in 11 patients.

CONCLUSIONSPreoperative radiochemotherapy can shrink the primary tumor and decrease lymph node metastasis rate. Patient with small tumor may have better response to preoperative radiochemotherapy.