Responses of Patients with T3-4N0-2M0 Rectal Cancer to Preoperative Chemoradiotherapy: Review of Current Literature

Objective: To investigate the efficacy and safety of chemoradiotherapy and radiotherapy followed by surgery in patients with locally advanced unresectable rectal cancer. Material and method: We reviewed records for 65 patients with locally advanced unresectable rectal cancer treated by preoperative chemoradiotherapy or radiotherapy followed by surgery between 2013 and 2016. Of these, 23 patients were treated with preoperative chemoradiotherapy (40 - 45 Gy) plus concomitant chemotherapy (5Fluorouracil + Calcium Folinate). For comparison, 42 similar patients treated by preoperative radiotherapy (45 - 50Gy) plus surgery served as control. The primary end-point of the study was overall survival and local control rate. Results: No treatment plan was delayed because of toxicities in both groups. The radical resectability rate was 69.9 % in the chemoradiotherapy group and 33.3 % in the radiotherapy plus surgery group (P = 0. 024). The anal sphincter preservation rates were 26. 6 % and 3. 7 %, respectively (P= 0. 028). The anal sphincter preservation rates of the lower rectal cancer were 27. 3 % and 0. 0 %, respectively (P = 0. 014). Response rates of chemoradiotherapy and radiotherapy plus surgery groups were 82.6 % and 61.9 % (P = 0. 053). The tumor downstage rates were 16 (69.6%) and 24 (57.1%) in these groups (P = 0. 206). The 3-years overall survival rates were 66. 7 % and 55. 6 % (P = 0. 485), and the tumor-free survival rates were 40. 3 % and 33. 1 % (P = 0. 663). The 3-years local recurrent rates were 26. 9 % and 48. 1 % (P = 0. 174) . No obvious late effects were found in either group. Conclusion: The results of this study suggested at least that acute side effects of preoperative chemoradiotherapy can be tolerated, and a higher surgical resection rate can be achieved. However, the chemoradiotherapy did not improve the survival rate while it increased local recurrence due to the high rate of anal sphincter preservation. It is safe and effective to use Fluorouracil + Folinate and 5 - DFUR as a radiosensitizer during the whole course of radiotherapy.