Role of Adjuvant Chemotherapy in ypT0-2N0 Patients Treated with Preoperative Chemoradiotherapy and Radical Resection for Rectal Cancer
Menée à partir de données portant sur 1 016 patients atteints d'un cancer du bas ou du moyen rectum de stade ypT0-2N0, cette étude évalue, du point de vue du taux de récidive locale et du taux de métastases distantes à 5 ans, l'intérêt d'ajouter une chimiothérapie adjuvante à un traitement comportant une chimioradiothérapie puis une résection radicale
Objective : To explore the role of adjuvant chemotherapy for patients with ypT0-2N0 rectal cancer treated by preoperative chemoradiotherapy (PCRT) and radical resection. Methods and materials : A national consortium of 10 institutions was formed, and patients with ypT0-2N0 mid- and low-rectal cancer after PCRT and radical resection from 2004–2009 were included. Patients were categorized into two groups according to receipt of additional adjuvant chemotherapy: Adj CTx (+) vs. Adj CTx (–). Propensity scores were calculated and used to perform matched and adjusted analyses comparing RFS between treatment groups while controlling for potential confounding. Results : 1016 patients, who met the selection criteria, were evaluated. Of these, 106 (10.4%) did not receive adjuvant chemotherapy. There was no overall improvement in 5-year RFS as a result of adjuvant chemotherapy (91.6% for Adj CTx(+) vs. 87.5% for Adj CTx(–), p=0.18). There were no differences in 5-year local recurrence and distant metastasis rate between the two groups. In patients who show moderate/minimal/no regression in tumor regression grade, however, possible association of adjuvant chemotherapy with RFS would be considered (HR, 0.35; 95% CI, 0.14–0.88; p=0.03). Cox regression analysis after propensity score matching failed to show that addition of adjuvant chemotherapy was associated with improved recurrence-free survival (HR, 0.81; 95% CI, 0.39–1.70; p=0.58). Conclusions : Adjuvant chemotherapy appeared to not influence the RFS of patients with ypT0-2N0 rectal cancer after PCRT followed by radical resection. Thus, the addition of adjuvant chemotherapy needs to be weighed against its oncologic benefits.
http://www.redjournal.org/article/S0360-3016(15)00198-4/abstract