Background: 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.
Methods: 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.
Results: 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.
Conclusion: Three-years disease-free survival was better in CRT group comparing with RT group with no difference in overall survival.
Trial registration: http://clinicaltrials.gov identifier NCT00597311. January 2008.
Keywords: Chemoradiotherapy; Rectal cancer.