Vinorelbine and cisplatin for metastatic breast cancer: a salvage regimen in patients progressing after docetaxel and anthracycline treatment.

PURPOSE

To assess the antitumor efficacy and safety of a combination of vinorelbine (VNR) and cisplatin in patients with metastatic breast cancer previously treated with anthracyclines and docetaxel.

PATIENTS AND METHODS

Thirty-six patients with assessable metastatic breast cancer previously treated with anthracyclines and docetaxel (adjuvant n = 1, palliative n = 20, both n = 15) were studied. Cisplatin was given at 75 mg/m2 on day 1 followed by 25 mg/m2 VNR on days 1 + 8 in a 5-minute i.v. infusion. Courses were repeated every 3 weeks. Treatment was continued until disease progression, excess toxicity, or patient refusal. Patients were classified according to their response to anthracyclines according to criteria published previously: 1) Anthracycline and/or docetaxel resistant were patients who progressed during treatment with anthracyclines and docetaxel or within 4 months after cessation of treatment (metastatic). In addition, adjuvant patients who progressed within 6 months after completion of chemotherapy belong to this group. 2) Anthracycline and/or docetaxel relapsed were either metastatic patients who responded initially and then progressed after 4 months of completing an anthracycline- and docetaxel-based chemotherapy or patients who progressed after 6 months from completion of anthracycline/docetaxel-based adjuvant chemotherapy.

RESULTS

Two patients (5.6%) achieved a complete response (CR) and 15 patients (41.6%) achieved a partial response (PR), for an overall response rate (OR) of 47.2% (95% confidence interval, 31-63). Of 18 patients relapsed to anthracycline/docetaxel, 2 had a CR (11%) and 8 a PR (44.4%), giving an objective response of 55.5%. Stable disease (SD) was observed in one patient (5.5%); seven patients had progressive disease (PD) (39%). Among the 18 resistant patients, 7 PRs (39%) were observed (p = 0.5), one patient (5.5%) had stable disease, 10 patients (55.5%) progressed. The median time to progression (TTP) was 16 weeks and median overall survival 36 weeks. Relapsed patients had a longer TTP than resistant patients (24 vs. 8 weeks, p = 0.05) but similar survival (48 vs. 24 weeks, p = 0.173). All patients were assessed for toxicity. The main toxicity was neutropenia grade 3 and 4 in 47% of patients. Febrile neutropenia requiring hospitalization was absent. There were no treatment-related deaths. Thrombocytopenia grade 3 and 4 occurred in four patients (11%). Phlebitis, orthostatic hypotension, and asthenia, all reversible, were observed in 3% of patients, respectively.

CONCLUSION

This cisplatin/VNR regimen is well tolerated and active in patients who failed anthracyclines and docetaxel treatment. The response rate, TTP, and survival data are high and indicate that cisplatin/VNR may have a place as salvage treatment in this group of patients. If these results can be verified in multi-institutional trials, this combination of drugs would merit investigation as part of a first-line therapy in breast cancer.