Dose Adjusted Neoadjuvant Paclitaxel, Carboplatin, Trastuzumab and Pertuzumab in Women With HER2 Positive Early...

Nine cycles of preoperative carboplatin with paclitaxel and anti-HER2 therapy is highly effective in early stage breast cancer. National guidelines include treating with 6 cycles of therapy with reduced dose of carboplatin. This study aimed to assess rates of pathological complete response (pCR), early discontinuation, dose reduction and toxicity with this regimen.

In this multi-center retrospective study, patients with stage II-III HER2-positive breast cancer who received 6 cycles of paclitaxel (80 mg/m² days 1 and 8) and reduced dose of carboplatin (AUC = 5 mg/mL/min) with trastuzumab and pertuzumab every 3 weeks were included. Clinicopathologic data and treatment delay, discontinuation, toxicity, and pCR rates were extracted from electronic medical records.

Over a 33 month period, 32 patients, median age 51 (range 30-65) years were included. Of these, most (66%) were premenopausal, 59% stage II and 69% had ER positive disease. All patients completed neoadjuvant therapy and underwent surgery. In total,19 patients (59%) completed all planned doses of neoadjuvant therapy without dose reductions and 7 patients (22%) had at least 1 dose reduction. In total, 21 patients (66%) underwent mastectomy and 11 (34%) underwent breast-conserving surgery. The pCR rate was 62.5 % (n = 20/32). There was a low rate of high grade toxicity recorded.

In this real world retrospective study, modified dose carboplatin with paclitaxel and anti-HER2 therapy for 6 cycles was associated with a high rate of complete response and a manageable toxicity profile which included favorable rates of early discontinuation and dose reduction.