Neoadjuvant chemotherapy is strongly recommended for patients (pts) with MIUBC, but the optimal perioperative chemotherapy regimen is not defined.
Between February 2013 and February 2018, 494 pts were randomized in 28 French centers and received either 4 cycles of GC every 3 weeks or 6 cycles of dd-MVAC every 2 weeks before surgery (neoadjuvant group) or after surgery (adjuvant group). The primary endpoint was the progression-free survival at 3 years. Secondary endpoints included toxicity, pathological responses and overall survival.
In the neoadjuvant group, 218 pts received dd-MVAC and 219 pts GC. The median number of cycles was 6 (0-6) and 4 (1-4), respectively. 60% of pts received 6 cycles in the dd-MVAC arm, 84% received 4 cycles in the GC arm. 199 pts (91%) and 198 (90%) pts underwent surgery, respectively. Complete pathologic responses (ypT0pN0) were observed in 84 (42%) and 71 (36%) pts, respectively (p=0.02). An organ-confined status (<ypT3pN0) was obtained in 154 (77%) and 124 (63%) pts, repectively (p=0.002). In the adjuvant group, the median number of cycles was 5 (1-6) and 4 (1-4), respectively. 40% of pts received 6 cycles in the dd-MVAC arm, 60% received 4 cycles in the GC arm. Most of CTCAE grade ≥ 3 toxicities concerned hematological toxicities, reported for 125 (50%) pts in the dd-MVAC group and 134 (54%) pts in the GC group (p=NS). Gastrointestinal (GI) grade ≥ 3 disorders were more frequently observed in the dd-MVAC arm (p<0.0001) as well as asthenia of grade ≥ 3 (p<0.00001). Four deaths (3 in dd-MVAC arm) occured during chemotherapy.
VESPER preliminary results suggested that the dd-MVAC toxicity was manageable with more severe asthenia and GI side effects than GC in perioperative chemotherapy. Moreover, we observed more frequently complete pathological reponses and organ-confined status in the dd-MVAC arm.