Oncologic outcomes of primary and post-irradiated early stage rectal cancer: a retrospective cohort study

AIM： To evaluate the oncologic outcomes of primary and post-irradiated early stage rectal cancer and the effectiveness of adjuvant chemotherapy for rectal cancer patients. METHODS： Eighty-four patients with stage Ⅰ rectal cancer after radical surgery were studied retrospectively and divided into ypstage Ⅰ group （n = 45） and pstage Ⅰ group （n = 39）, according to their preoperative radiation, and compared by univariate and multivariate analysis. RESULTS： The median follow-up time of patients was 70 mo. No significant difference was observed in diseaseprogression between the two groups. The 5-year disease-free survival rate was 84.4% and 92.3%, respectively （P = 0.327） and the 5-year overall survival rate was 88.9% and 92.3%, respectively, for the two groups （P = 0.692）. The disease progression was not significantly associated with the pretreatment clinical stage in ypstage Ⅰ group. The 5-year disease progression rate was 10.5% and 19.2%, respectively, for the patients who received adjuvant chemotherapy and for those who rejected chemotherapy in the ypstage Ⅰ group （P = 0.681）. CONCLUSION： The oncologic outcomes of primary and post-irradiated early stage rectal cancer are similar. Patients with ypstage Ⅰ rectal cancer may slightly benefit from adjuvant chemotherapy.