Combination treatment of rectal cancer using polyradiomodification and short courses of neoadjuvant radiotherapy

Objective : to improve the outcomes of combination treatment of patients with rectal cancer using polyradiomodification and short courses of neoadjuvant radiotheragy. Materials and methods . A total of 905patients were included into this retrospective study based on the data retrieved from a prospective database. Of them, 241 patients underwent combination treatment with polyradiomodification (CT + PRM); 271 patients underwent combination treatment with preoperative radiotherapy alone (CT); 393patients underwent surgical treatment only (ST). Combination treatment with polyradiomodification included a course of radiotherapy with a total dose of 25 Gy delivered in 5 fractions (5 Gy each), rectal administration of biopolymer composition containing metronidazole at a dose of 10 g/m 2 (5-h exposure in the rectum on days 3 and 5), and chemotherapy with capecitabine at a dose of 2 g/m2 on days 1—14 followed by surgery within the next 4—6 weeks. We analyzed the incidence of postoperative complications, 5-year relapse-free survival, and frequency of relapses. Results . The incidence of grade IIIB postoperative complications was significantly lower in patients who underwent combination treatment with polyradiomodification than in those who had surgery only (p = 0.0023) and those who had combination therapy without polyradiomodification (p = 0.0003). The 5-year relapse-free survival rate was 80.5 % in the group of CT + PRM compared to 64.9 % in the group of CT (p = 0.00315) and 60.1 % in the group of ST (p = 0.000001). The frequency of relapses was 0.4 %, 8.5 % (p = 0.00001), and 13.7 % (p = 0.00001) in the groups CT + PRM, CT, and ST respectively. There were no significant differences in the incidence of distant metastasis between the groups. Conclusions . The developed variant of combination treatment with polyradiomodification did not increase the number of complications and ensured better relapse-free survival due to improved locoregional control.