Long-term treatment outcomes in patients with low rectal cancer

Abstract

Objective: to assess the effect of preoperative treatment option on the number of sphincter-preserving operations (SPO) in patients with low rectal cancer. Materials and methods . The patients with low rectal cancer (0—6 cm from anocutaneous line) were randomized into 3 groups: in the 1st control group surgery was performed in 0—3 days after completion of short-course radiotherapy (5 х 5 Gy). Patients in the 2nd control group received identical radiotherapy but the interval before surgery was extended to 42 ± 3 days. Patients in the study group received treatment identical to 2nd control group with 2 additional courses of monochemotherapy with capecitabine, starting on the first day of radiotherapy. The primary endpoint was the number of SPO. Complete pathomorphologic response rate, overall survival, tumor-specific survival and event-free 5-year survival were also assessed as secondary endpoints. Results. Data on 129 patients was analyzed: 46 in the 1st control group, 43 in the 2nd control group, 40 in the study group. The proportion of SPO was 41,3 ± 7,3 % in the 1st group, 69,7 ± 7,0 % and 77,5 ± 6,6 % in the 2nd group and study group, respectively. Complete histological response was achieved in 15 % of patients in study group, comparing to 14,3 % of patients in the 2nd group. Overall 5-year survival in this study was estimated to be 77,8 ± 4,5%, tumor-specific survival — 89,7 ± 3,7 %, event-free survival — 90,1 ± 2,9 %, with no significant differences between groups. Conclusion. Short-course radiotherapy (5 х 5 Gy) with 6-week interval before surgery resulted in increase of SPO rate with no affect on oncologic outcome.