Résumé
BACKGROUND: Systematic preoperative radiochemotherapy and total mesorectal excision are the standard of care for locally advanced rectal carcinoma. Some patients can be over- or undertreated.
OBJECTIVE: This study aimed to investigate the long-term oncological, functional, and late morbidity outcomes after tailored radiochemotherapy and induction high-dose chemotherapy.
DESIGN: This is a prospective, phase II, multicenter, open-label study at 16 tertiary centers in France. SETTINGS: Patients were operated on by surgeons from the French GRECCAR group.
PATIENTS: Two hundred six patients were randomly assigned to treatment: good responders after chemotherapy (>= 75% tumor volume reduction) to immediate surgery (arm A) or standard radiochemotherapy (capecitabine 50) plus surgery (arm B) and poor responders to capecitabine 50 (arm C) or intensive radiochemotherapy (capecitabine 60; 60 Gy irradiation; arm D) before surgery.
INTERVENTIONS: Treatment was tailored according to MRI response to induction chemotherapy. RESULTS: After induction treatment, 194 patients were classified as good (n = 30, 15%) or poor (n = 164, 85%) responders; they were included in arms A and B (16 and 14 patients) or C and D (113 and 51 patients). The primary objective was obtained: R0 resection rates (90% CI) in the 4 arms were 100% (74-100), 100% (85-100), 83% (72-91), and 88% (77-95). At 5 years, overall survival rates were 90% (47.3-98.5), 93.3% (61.3-99.0), 84.3% (71.0-91.8), and 86.1% (71.6-93.5); disease-free survival rates were 80% (40.9-94.6), 89.5% (64.1-97.3), 72.9% (58.5-82.9), and 72.8% (57.7-83.2); local recurrence rates were 0%, 0%, 2.1% (0.3-13.9), and 9.3% (3.6-23.0); and metastasis rates were 20% (5.4-59.1), 10.5% (2.7-35.9), 18% (31.8-94.6), and 18.8% (10.2-33.0). Late morbidity and quality-of-life evaluations showed no significant difference between arms.
LIMITATIONS: Limitations were due to the small number of patients randomly assigned in the good responder arms, especially arm A without radiotherapy.
CONCLUSION: Tailoring preoperative radiochemotherapy based on induction treatment response appears to be promising. Future prospective trials should confirm this strategy. See Video Abstract at http://links.lww.com/DCR/B761.