Combined modality treatment with preoperative radiation therapy (RT) + capecitabine is a standard of care for locally advanced rectal adenocarcinoma. However, new strategies to improve outcomes are necessary. We previously reported neither differences in pathologic complete response (primary objective) nor in safety results with preoperative RT + capecitabine with or without Bev. We present now the Disease-free survival (DFS), distant relapse free survival (RFS) and Overall Survival (OS) data at 3 and 5 years.
Patients (pts) were randomized in a 1:1 ratio to 5 weeks (w) of RT 45 Gy with concurrent capecitabine 825 mg/m2 bid x 5 d/w with Bevacizumab (Bev) 5 mg/kg q2w (3 doses) (arm A) or without Bev (arm B). Adjuvant systemic chemotherapy administration was upon investigatoŕs criteria.
Ninety pts were included (44 in arm A and 46 in arm B). Preoperative treatment compliance was similar in both arms. Seventy-five pts received adjuvant systemic chemotherapy: 34 (77.3%) in arm A and 41 (89.1%) in arm B (p = 0.1313). One pt (arm B) developed local relapse. Eleven pts in arm A and 10 in arm B developed distant metastasis. With a median follow-up of 63.5 and 63.5 months for arms A and B, respectively, median DFS, median RFS and median OS have not been reached for both arms. DFS at 3 y and 5 y was 75.0% and 68.2% (arm A) vs 71.7% and 69.6% (arm B), respectively (5-y DFS, p = 0.9820). Distant RFS at 3 y and 5 y was 81.0% and 76.2% (arm A) vs 80.4% and 78.3% (arm B), respectively (5y-distant RFS, p = 0.6923). OS was 88.6% and 81.0% (arm A) vs 95.7% and 87.0% (arm B) at 3 and 5y, respectively (5-y OS, p = 0.3350). Five pts had a second malignancy (1 in arm A, 4 in arm B), without significant differences between arms.
In our study, the addition of bevacizumab to capecitabine and radiotherapy in the neoadjuvant setting for locally advanced rectal cancer does not confer benefits in DFS, RFS or OS.
Clinical trial identification
Legal entity responsible for the study
The Spanish Cooperative Group for the Treatment of Digestive Tumors (TTD)
All authors have declared no conflicts of interest.