Long-term results of preoperative chemoradiation for distal rectal cancer correlation between final stage and survival

Abstract

Neoadjuvant chemoradiation treatment (CRT) has resulted in significant tumor downstaging and improved local disease control for distal rectal cancer. The purpose of the present study was to determine the correlation between final stage and survival in these patients regardless of initial disease stage. Two hundred sixty patients with distal (0-7 cm from anal verge) rectal adenocarcinoma considered resectable were treated by neoadjuvant CRT with 5-FU and leucovorin plus 5040 cGy. Patients with incomplete clinical response 8 weeks after CRT completion were treated by radical surgical resection. Patients with complete clinical response were managed by observation alone. Overall survival and disease-free survival were compared according to Kaplan-Meier curves and log-rank tests according to final stage. Seventy-one patients (28%) showed complete clinical response (clinical stage 0). One hundred sixty-nine patients showed incomplete clinical response and were treated with surgery. In 22 of these patients (9%), pathologic examination revealed pT0 N0 M0 (stage p0), 59 patients (22%) had stage I, 68 patients (26%) had stage II, and 40 patients (15%) had stage III disease. Overall survival rates were significantly higher in stage c0 (P=0.01) compared with stage p0. Disease-free survival rate showed better results in stage c0, but the results were not significant. Five-year overall and disease-free survival rates were 97.7% and 84% (stage 0); 94% and 74% (stage I); 83% and 50% (stage II); and 56% and 28% (stage III), respectively. Cancer-related overall and disease-free survival may be correlated to final pathologic staging following neoadjuvant CRT for distal rectal cancer. Also, stage 0 is significantly associated with improved outcome.