Predictive factors of positive circumferential resection margin after radiochemotherapy for rectal cancer: The French randomised trial ACCORD12/0405 PRODIGE 2

Anne Rullier (1) , Sophie Gourgou-Bourgade (2) , Marta Jarlier (2) , Frédéric Bibeau (2) , Catherine Chassagne-Clement (3) , Christophe Hennequin (4) , Laurent Tisseau (5) , Agnès Leroux (6, 7) , Francette Ettore (8) , Michel Peoc'H (9) , Marie-Agnès Diebold (10) , Yves-Marie Robin (11) , Isabelle Kleinclaus (12) , Laurent Mineur (13) , Christophe Petitjean (14) , Jean-François Mosnier (15) , Isabelle Soubeyran (16) , Norbert Padilla (17) , Anne-Isabelle Lemaistre (18) , Jocelyne Bérille (19) , Bernard Denis (12) , Thierry Conroy (7, 6) , Jean-Pierre Gérard (8)

1 CHU Bordeaux
2 Centre Régional de Lutte contre le Cancer Val d'Aurelle
3 Centre Léon Bérard [Lyon]
4 Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)
5 Laboratoire de Pathologie [Saint Brieuc]
6 UNICANCER/ICL - Institut de Cancérologie de Lorraine - Alexis Vautrin [Nancy]
7 APEMAC - Maladies chroniques, santé perçue, et processus d'adaptation
8 UNICANCER/CAL - Centre de Lutte contre le Cancer Antoine Lacassagne [Nice]
9 Laboratoire de Pathologie [Saint Priest en Jarez]
10 Hôpital Robert Debré
11 UNICANCER/Lille - Centre Régional de Lutte contre le Cancer Oscar Lambret [Lille]
12 CH Colmar - Hôpital Louis Pasteur [Colmar]
13 Institut Sainte Catherine [Avignon]
14 Laboratoire medipath [Hyères]
15 Centre Hospitalier Universitaire de Nantes - Hôpital Hôtel-Dieu [Nantes]
16 Institut Bergonié [Bordeaux]
17 Laboratoire de Pathologie [Le Mans]
18 Laboratoire de Pathologie [Lyon]
19 UNICANCER [Paris]

Circumferential resection margin (CRM) appears as a new powerful prognostic factor of survival after surgery for rectal cancer. We aimed to evaluate predictive factors of positive CRM following preoperative radiochemotherapy in a French trial. Patients with rectal cancer were randomised in long course preoperative radiotherapy 45 Gy plus capecitabine versus 50 Gy plus capecitabine and oxaliplatin. Mesorectal excision was performed 6 weeks after treatment. Impact of clinical, pathological and surgical variables on positive CRM (≤1 mm) were analysed by multivariate analysis. Of 565 randomised patients, CRM was recorded in 390 cases and was positive in 8% (30/390). Patients with 50 Gy plus capecitabine and oxaliplatin had a 6% rate of positive CRM while those treated by 45 Gy plus capecitabine had a 10% rate (p=0.128). Three independent predictive factors of positive CRM were identified: abdominoperineal resection (APR) (odds ratio OR=3.24; p=0.004), vascular tumour invasion (OR=2.78; p=0.026) and poor histological response (modified Dworak 0-2) (OR=9.01; p=0.003). Significant predictive factors of positive CRM are related to type of surgery, especially APR, and poor histological prognostic factors. Intensification of neoadjuvant radiochemotherapy does not seem to have a major role in this study.

Domaines: Santé publique et épidémiologie

Anne Rullier, Sophie Gourgou-Bourgade, Marta Jarlier, Frédéric Bibeau, Catherine Chassagne-Clement, et al.. Predictive factors of positive circumferential resection margin after radiochemotherapy for rectal cancer: The French randomised trial ACCORD12/0405 PRODIGE 2. European Journal of Cancer, 2013, 49 (1), pp.82 - 89. ⟨10.1016/j.ejca.2012.06.028⟩. ⟨hal-01797382⟩