There still is no evidence which neoadjuvant therapy regimen for stage II–III rectal cancer is superior. The aim of this study was to compare results achieved after long-course chemoradiotherapy (CRT) with short-term radiotherapy (RT) followed by delayed surgery. A randomized trial was carried out between 2007–2013. One hundred fifty patients diagnosed with stage II–III rectal cancer were randomized into one of two neoadjuvant treatment arms: conventional chemoradiotherapy (CRT) and short-term radiotherapy (RT) followed by surgery after 6–8 weeks. Primary endpoints of this trial were downstaging and pathological complete response rate. Secondary endpoints were local recurrence rate and overall survival. The pathological complete response was found in 3 (4.4%) cases after RT and 8 (11.1%) after CRT (P = 0.112). Downstaging (stage 0 and I) was observed in 21 (30.9%) cases in RT group vs. 27 (37.5%) cases in CRT group (P = 0.409). Median follow-up time was 39.7 (range 4.9–79.7) months. 3-years overall survival (OS) was 78% in RT group vs. 82.4% in CRT group (P = 0.145), while disease-free survival (DFS) differed significantly – 59% in RT group vs. 75.1% in CRT group (P = 0,022). Hazard ratio of cancer progression for RT patients was 1.93 (95% CI: 1.08–3.43) compared to CRT patients. Three-years disease-free survival was better in CRT group comparing with RT group with no difference in overall survival. http://clinicaltrials.gov identifier NCT00597311. January 2008.

At present, there are common recommendations for treatment for stage II-III resectable rectal cancer patients: preoperative conventional chemoradiotherapy (CRT) with delayed surgery in 6-8 weeks or preoperative short-course radiotherapy (SCRT) followed by immediate surgery. The aim of this study was to compare overall survival (OS) and disease-free survival (DFS) in two treatment groups: preoperative SCRT and CRT both with delayed surgery plus adjuvant chemotherapy in CRT arm. A total of 150 patients were randomly assigned to two groups: 75 to CRT (preoperative conventional CRT, 50Gy/25 fr with fluorouracil and leucovorin on the 1st and the 5th week of RT followed by TME surgery in 6-8 weeks and 4 cycles of adjuvant fluorouracil/leucovorin every 4 weeks; then follow-up) and 75 to SCRT (preoperative short-course RT, 25Gy/5 fr followed by TME surgery in 6-8 weeks; then follow-up). The data of 140 patients (72 in CRT and 68 in SCRT group) were included in statistical analysis. Primary end points were OS and DFS. Median follow-up was 60.5 (range, 5-108) months. The 5-year DFS was 67% in the CRT group (n=72) and 45% in the SCRT group (n=68) (P=0.013; HR=1.88; 95% CI, 1.13-3.12; P=0.015). The 5-year OS was 79% and 62% in the CRT and SCRT groups, respectively (P=0.015; HR=2.05; 95% CI, 1.13-3.70; P=0.017). The 5-year OS for intent-to-treat (ITT) population (n=150) was 78% in the CRT and 58% in the SCRT group (P=0.003; HR=2.28; 95% CI, 1.30-4.00; P=0.004). The 5-year DFS and OS were significantly better in the CRT than the SCRT group. For ITT population, OS was also significantly better after CRT versus SCRT.