Phase II Study With Epirubicin, Cisplatin, and Infusional Fluorouracil Followed by Weekly Paclitaxel With Metronomic Cyclophosphamide as a Preoperative Treatment of Triple-Negative Breast Cancer

Abstract

Background: The aggressive biological behavior and the lack of target therapy prompts the search for new therapeutic approaches for triple-negative breast cancers.

Patients and methods: We evaluated the efficacy in terms of Ki-67 variation and clinical response but also the toxicity of a neoadjuvant regimen based on metronomic principles including ECF (epidoxorubicin with cisplatin on day 1 with low-dose 5-fluorouracil in continuous infusion every 21 days for 4 courses) followed by paclitaxel (90 mg/m(2)) on day 1, 8, and 15 every 28 days for 3 courses in combination with metronomic oral cyclophosphamide 50 mg/d for 12 weeks in patients with HER2-negative breast cancer (T2-T4a-d, N0-3, M0) with estrogen receptor and progesterone receptor < 10%.

Results: We enrolled 34 patients from June 2009 to May 2013. All were considered evaluable on an intention-to treat basis. The mean difference between the percentage of Ki-67 positive cells evaluated in surgical resection specimens and in pretreatment tumor core biopsy was 41% (95% confidence interval [CI], 30-51; P < .0001) for the entire population, and 22% (95% CI, 7-38; P = .0097) in patients who did not achieve pathological complete response (pCR). Responses to the treatment were obtained in 31 patients [91%] of the patients, and 19 patients (56%; 95% CI, 35-70) had a pCR. Stable disease was observed in 3 patients and none had progressive disease. Grade ≥ 3 hematologic adverse events included leukopenia in 9% (3 of 34), neutropenia in 38% (13 of 34), and anemia in 3% (1 of 34) of patients. Nonhematologic Grade ≥ 3 toxicities included only stomatitis in 1 patient.

Conclusion: A neoadjuvant program with an ECF regimen followed by weekly paclitaxel with metronomic cyclophosphamide proved to be very effective, with high pCR rates, reduction of Ki-67, and it was associated with a low toxicity profile.

Keywords: Chemotherapy; Ki-67; Metronomic therapy; Neoadjuvant; Pathological complete response.