Predictors of pCR to neoadjuvant chemotherapy (NAC) for breast cancers have been studied extensively. We focused on CR to antracycline-based chemotherapy using MRI for prediction of pCR, in patients treated with NAC with anthracycline and taxane-based regimens.
Tumor measurements were done at diagnosis, after anthracyclines and at the end of taxanes. pCR was defined as absence of residual invasive foci and no lymph nodeinvolvement. Associations of clinicopathologic parameters with pCR were evaluated with the χ2 test. All test results with a p value of less than 0.05 were considered significant.
A total of 114 TNBC patients were treated with NAC. Median age was 53 (28-77) years. 44 patients (38.6%)had stage II and 67(58.8%)stage III. Mutation in BRCA was detected in 9 patients and variants of uncertain significance in 5. 49 patients (43%) with tumor size by MRI > 50 mm, 49 (43%) with positive results on fine needle aspiration of axilla (FNAA), and 88 (77.2%) with histologic grade III. NAC regimen consisted in 108 patients (94.7%) of 4 cycles of epirrubicin+cyclophosphamide (CP) and in 3 patients (2.6%) 4 cycles of doxorubicin+CP, followed by taxane-based regimens. 43 patients (37.7%) had pCR. CR by MRI occurred in 22 patients (19.3%) after anthracycline-based regimen. At the end of NAC there were 37 patients (32.5%) with CR by MRI. Association of clinicopathologic parameters with pCR were: 62.8% pCR in patients with tumor size ≤ 50mm (p = 0.389); 58.1% in patients with FNAA + (p = 0.238); 81.4% in grade III tumors (p = 0.700); 46.5% pCR in patients with CR by MRI after anthracycline-based regimen (p = 0.0001) and 65.1% pCR in patients with CR by MRI before surgery (p = 0.0001). All the patients with CR by MRI after anthracycline-based regimen had a CR by MRI before surgery.
CR by MRI after treatment with anthracyclines could be a clinically useful predictor of pCR in patients with TBNC treated preoperatively with anthracylcines and taxane-based regimens and patients who not reach CR after anthraclines could benefit from improve taxans regimen.
Luis Antonio Fernandez Morales.
Has not received any funding.
All authors have declared no conflicts of interest.