Is It Beneficial for Patients with pT1-2N1M0 Breast Cancer to Receive Post-Mastectomy Radiotherapy? An Analysis Based on RecurIndex Assay

Menée à l'aide de données portant sur 213 patientes atteintes d'un cancer du sein de stade pT1-2N1M0 traité par mastectomie entre 2011 et 2015 (durée médiane de suivi : 77 mois), cette étude évalue l'efficacité, du point de vue de la survie sans récidive, d'un traitement par radiothérapie postopératoire

Résumé en anglais

The benefit of post-mastectomy radiotherapy (PMRT) for pT1-2N1M0 breast cancer patients currently remains controversial. This study was conducted to investigate whether pT1-2N1M0 breast cancer patients could benefit from PMRT based on RecurIndex assay. The clinical data of 213 pT1-2N1M0 breast cancer patients were retrospectively analyzed. Through RecurIndex assay, 81 cases were assessed as the low risk, and 132 as the high risk. Compared with low-risk patients, high-risk patients especially those not receiving PMRT had a significantly increased risk of recurrence and metastasis, and worse 7-year local-regional recurrence-free interval (LRFI), distance recurrence-free interval (DRFI) and recurrence-free survival (RFS) rates. PMRT-based subgroup analysis indicated no significant differences between the low-risk patients with and without PMRT in 7-year LRFI, DRFI, RFS and overall survival (OS) rates, but apparent differences were all shown between the high-risk patients with and without PMRT in 7-year LRFI, DRFI, RFS and OS rates. Overall, for pT1-2N1M0 breast cancer patients at low risk of recurrence and metastasis stratified by RecurIndex assay, there may be a phenomenon of no PMRT benefits, while for those at high risk, use of PMRT may produce survival benefits.