First-line treatment with mitoxantrone, methotrexate, vincristine, and carboplatine (MIMOC) plus cyclical hormonotherapy with tamoxifen and megestrolacetate in advanced breast cancer

Fifty patients with stage IIIB and IV breast cancer entered a prospective s tudy receiving combination chemotherapy consisting of mitoxantrone (8 mg/m( 2)) on day 1, methotrexate (30 mg/m2) on day 1, vincristine (1 mg/m(2)) on day 2, and carboplatine (250 mg/m(2)) on day 2 (MIMOC), plus cyclical hormo notherapy with tamoxifen (20 mg daily, days 1-10) and megestrol acetate (16 0 mg daily, days 11-21). The regimen was repeated every 3 weeks. None had r eceived chemotherapy for advanced disease, although 17 patients had previou sly received adjuvant chemotherapy and 21 had received adjuvant hormonother apy with tamoxifen. Twenty-seven patients had positive estrogen receptor (E R+) status, and 23 negative estrogen receptor (ER-) status. Response was ob served in 31 (62%) of the 50 analyzed patients (95% CI: 48.5-75.4%), with 5 complete responses (10%). A significantly better response rate was observe d in ER+ patients (p = 0.03). The median duration of response was 16 months , and the median time to disease progression was 18 months. The median over all survival was 19 months (27 for responders and 7 for nonresponders). ER patients had a higher probability of survival (p = 0.02). Toxicity was mod erate. Nausea/vomiting and myelotoxicity were the main side effects. In con clusion, MIMOC plus cyclical hormonotherapy represents a well-tolerated and effective first-line treatment for advanced breast cancer. The observed di fference in response and survival in favor of ER+ patients warrants further investigation.