Background
Perioperatory chemoradiotherapy (CRT) improves local control and survival in patients with locally advanced rectal cancer (LARC). The
Conclusions
The addition of BEV to CAP-based preoperative CRT has shown to be feasible in LARC. The association between decreasing Ang-2 levels and tumor downstaging should be further validated in customized studies. Trial registry: Clinicaltrials.gov identifier NCT01043484.
Methods
Patients (pts) were randomized to receive 5 weeks of radiotherapy 45 Gy/25 fractions with concurrent CAP 825 mg/m(2) twice daily 5 days per week and BEV 5 mg/kg once every 2 weeks (3 doses) (arm A), or the same schedule without BEV (arm B). The primary end point was pathologic complete response (ypCR: ypT0N0).
Results
Ninety pts were included in arm A (44) or arm B (46). Grade 3-4 treatment-related toxicity rates were 16% and 13%, respectively. All patients but one (arm A) proceeded to surgery. The ypCR rate was 16% in arm A and 11% in arm B (p =0.54). Fifty-nine percent vs 39% of pts achieved T-downstaging (arm A vs arm B; p =0.04). Serial samples for biomarker analyses were obtained for 50 out of 90 randomized pts (arm A/B: 22/28). Plasma angiopoietin-2 (Ang-2) levels decreased in arm A and increased in arm B (p <0.05 at all time points). Decrease in Ang-2 levels from baseline to day 57 was significantly associated with tumor downstaging (p =0.02). Conclusions: The addition of BEV to CAP-based preoperative CRT has shown to be feasible in LARC. The association between decreasing Ang-2 levels and tumor downstaging should be further validated in customized studies. Trial registry: Clinicaltrials.gov identifier NCT01043484.