TBCRC 031: Randomized Phase II Study of Neoadjuvant Cisplatin Versus Doxorubicin-Cyclophosphamide in Germline BRCA Carriers With HER2-Negative Breast Cancer (the INFORM trial)
Mené sur 118 patientes atteintes d'un cancer du sein HER2- et porteuses d'une mutation constitutionnelle BRCA (âge moyen : 42 ans), cet essai de phase II compare l'efficacité, du point de vue du taux de réponse complète, et la toxicité d'une chimiothérapie néoadjuvante par cisplatine et d'une chimiothérapie combinant doxorubicine et cyclophosphamide avant le traitement chirurgical
PURPOSE : Platinum compounds have activity in triple-negative breast cancer (TNBC) in germline BRCA mutation carriers (BRCA carriers). Limited data exist for estrogen receptor (ER)–positive (+) breast cancer among BRCA carriers. INFORM is a randomized, multicenter, phase II trial comparing pathologic complete response (pCR) rates (ypT0/is, N0) after neoadjuvant single-agent cisplatin (CDDP) versus doxorubicin-cyclophosphamide (AC) in BRCA carriers with stage I-III human epidermal growth factor receptor 2 (HER2)–negative breast cancer. Secondary objectives included residual cancer burden scores (RCB) of 0 or 1 (combined) and toxicity. The goal was to determine whether pCR was ≥ 20% higher with CDDP than AC. PATIENTS AND METHODS : BRCA carriers with cT1-3 (≥ 1.5 cm), cN0-3 HER2-negative breast cancer were randomly assigned to preoperative CDDP (75 mg/m2 every 3 weeks × 4 doses) or AC (doxorubicin 60 mg/m2; cyclophosphamide 600 mg/m2 every 2-3 weeks × 4 doses) followed by surgery. Pathologic responses were confirmed by central review. RESULTS : A total of 118 patients were randomly assigned; 117 were included in outcome analyses. Mean age was 42 years (range, 24-73 years); 69% were BRCA1+, 30% were BRCA2+, and 2% had both mutations. Clinical stage was I for 19%, II for 63%, and III for 18%; 45% had nodal involvement at baseline. Seventy percent had TNBC. Clinical and tumor characteristics were well matched between treatment arms. The pCR rate was 18% with CDDP and 26% with AC, yielding a risk ratio (RR) of 0.70 (90% CI, 0.39 to 1.2). The risk of RCB 0 or 1 (RCB 0/1) was 33% with CDDP and 46% with AC (RR, 0.73; 90% CI, 0.50 to 1.1). Both regimens were generally well tolerated without unexpected toxicities. CONCLUSION : pCR or RCB 0/1 is not significantly higher with CDDP than with AC in BRCA carriers with stage I-III HER2-negative breast cancer for both TNBC and ER+/HER2-negative disease.