607P - Efficacy and safety of two neoadjuvant strategies with bevacizumab in locally advanced resectable rectal cancer: interim results of a randomized, no...

Date 01 October 2012
Event ESMO Congress 2012
Session Poster presentation III
Topics Anti-Cancer Agents & Biologic Therapy
Rectal Cancer
Presenter Jean-François Bosset
Authors J. Bosset1, G. Mantion2, T. André3, F. Boudghène4, F. Piard5, F. Mornex6, P. Maingon7, A. Adenis8, M. Piutti9, C. Borg10
  • 1Radiation-oncology, CHU Jean Minjoz, 25030 - Besançon/FR
  • 2Service De Chirurgie Digestive Et Vasculaire, Hôpital Jean Minjoz, Besançon/FR
  • 3Medical Oncologie, Hôpital Saint Antoine, Paris/FR
  • 4Service Imagerie Médicale, Hôpital TENON, 75020 - Paris/FR
  • 5Service D'anatomo-pathologie, CHU de Dijon, Dijon/FR
  • 6Radiothérapie-oncologie, Centre Hospitalier Lyon-Sud, Lyon/FR
  • 7Radiothérapie, Centre Georges-François-Leclerc, Dijon/FR
  • 8Centre Oscar Lambret, FR-59020 - Lille CEDEX/FR
  • 9Responsable Etudes Cliniques, Laboratoires Roche, Boulogne-Billancourt/FR
  • 10Medical Oncology, Hopital Minjoz, 25000 - besançon/FR

Abstract

Background

Current therapy of locally advanced resectable rectal cancer (LARC) involves a combination of chemotherapy (CT), radiation therapy, (RT) and total mesorectal excision (TME) surgery. Two neoadjuvant strategies with bevacizumab (Bv) were assessed in a randomized, open-label, multicentre, phase II study.

Method

Patients (pts) were treated with a sequential strategy including induction Bv/6 cycles (5mg/2weeks) + Folfox4, followed by CT-RT (Bv/6 cycles + 5-FU/5 cycles) + RT(45Gy) then TME in Arm A and the same CT-RT, then TME in Arm B. Primary end-point was tumor sterilization rate (pCR) - at least 10% in each arm. Efficacy and safety were reviewed by an independent committee. Results at 8 weeks post-surgery are presented.

Results

Pts characteristics in Arm A (n = 46) and in Arm B (n= 45) were: men 67%, age 60 ± 9 years, ECOG score 0 (85%), mid-rectum (60%), low-rectum (40%), MRI stage: T3N0M0/T3N1M0/T3N2M0 (20%/65%/15%). In Arm A, 94% pts completed induction and 91% had CT-RT and surgery; in Arm B 100% had CT-RT and 98% surgery. Resection was macroscopically complete in 91% pts. Median post-surgery hospitalization duration was 15 [0-84] days. In the ITT population, pCR (ypT0-N0) rate was 23.8% [12.1%-39.5%] in Arm A (p = 0.015) and 11.4% [3.8%-24.6%] in Arm B (p = 0.91), both compared to the 10% pCR initial hypothesis. Central review found similar results for pCR. At surgery and 4 weeks post-surgery grade 3/4 adverse events (AE) were reported in 10 (22%) of pts in both arms. At 8 weeks post-surgery, grade 3/4 adverse events (AE) were reported in 59% of pts in Arm A and 36% in Arm B. Grade 3/4 AEs of special interest for bevacizumab were reported in 20% of pts in Arm A and 22% in Arm B. No death was reported at 8 weeks post-surgery follow-up.

Conclusions

Interim results in patients with LARC treated with 2 neoadjuvant strategies showed that bevacizumab combination to neoadjuvant CT-RT did not significantly increase pCR in Arm B. The neoadjuvant strategy assessed in Arm A seems promising and deserves further investigation. Safety was comparable in Arms A and B at 8 weeks post-surgery.

Disclosure

T. André: Consultant: Roche Honoraries: Amgen, Merck, Sanofi.

F. Boudghène: Honoraries : Roche.

M. Piutti: Employment: Roche.

All other authors have declared no conflicts of interest.