Cisplatin-epirubicin-paclitaxel weekly administration with G-CSF support in advanced breast cancer. A Southern Italy...

It has been shown in vitro that both cisplatin and epirubicin increase the antitumor activity of paclitaxel. Weekly administration could give a substantial improvement in the therapeutic index of cisplatin and paclitaxel. This study was aimed at defining the antitumor activity of a weekly cisplatin-epirubicin-paclitaxel (PET) administration in locally advanced or metastatic breast cancer patients.

Sixty-eight breast cancer patients with advanced disease, who had not received prior chemotherapy (except adjuvant), received weekly cisplatin 30 mg/sqm, paclitaxel 120 mg/sqm and epirubicin 50 mg/sqm plus G-CSF (day 3-5), for a maximum of 12 cycles. Thirty-five patients had stage IIIB and 33 stage IV disease (14 with visceral metastases).

All patients were evaluable for response on an intent to treat basis. Overall, 21 complete and 38 partial responses have been recorded for an 87% ORR (95% CI = 76-94%). Fourteen CRs and 19 PRs have been registered in the 35 patients with locally advanced disease for a 94% ORR (95% CI = 81-99%) while 7 CRs and 19 PRs were observed in the 33 patients with metastatic disease for a 79% ORR (95% CI-61-91%). Surgery was performed in 33/35 women with locally advanced disease. Four of these patients (11%) showed no invasive cancer on pathologic examination, and in an additional 8 patients tumor < 1 cm was found in the breast. Only 4/33 patients who underwent surgery relapsed. The projected one-year RFS was greater than 80%. At an 11-month median follow-up (range, 3-19), 11 patients had progressed and 5 had died among the 33 patients with metastatic disease, the median progression-free survival in this group being 14 months. Severe hematologic toxicity was uncommon, grade 3-4 neutropenia and thrombocytopenia occurring in 32% and 4% of patients, respectively. Only 2 episodes of neutropenic sepsis were registered. Packed red blood cell transfusions were required in 7 patients. Vomiting, diarrhoea, mucositis and skin toxicity were severe in 6%, 9%, 10%, and 9% of patients, respectively. Peripheral neuropathy was observed in 47% of patients.

The weekly PET administration is a well tolerated and very effective approach in advanced breast cancer patients. It can produce a 40% clinical complete response rate, with a more than 10% pCR rate in patients with T4 disease, and an about 80% ORR in those with distant metastases. A phase III trial comparing PET with a standard every 3 weeks epirubicin-taxol administration is underway.