Carboplatin plus gemcitabine repeating doublet therapy in recurrent breast cancer

The combination of cisplatin plus gemcitabine is active in metastatic breast cancer. Carboplatin plus gemcitabine, widely used in ovarian and non-small-cell lung cancers, has also been used in breast cancer. This trial examined the efficacy and toxicity of split-dose carboplatin plus gemcitabine in advanced breast cancer.

Patients with measurable disease, recurrent after adjuvant and < or = 1 previous treatment for systemic disease, received carboplatin area under the curve = 2.0 (Calvert) plus gemcitabine 800 mg/m2, both drugs administered days 1 and 8 every 21 days. Of 15 patients accrued, 13 are fully evaluable.

There were 2 complete (13.3%) and 6 partial (40%) responses, for an overall response rate by intention to treat of 53.3% (95% CI, 28%-82%). The median time to progression was 4.5 months (95% CI, 2.03-6.97 months), and median overall survival was 28.8 months (95% CI, 9.4-48.2 months). There were 2 patients with grade 3 (13.3%) anemia, 7 patients with grade 3 (46.6%) and 4 patients (26.6%) with grade 4 neutropenia, 4 patients with grade 3 (26.6%) and 3 patients (20%) with grade 4 thrombocytopenia.

The repeating doublet of split-dose carboplatin plus gemcitabine reveals activity comparable to that of cisplatin plus gemcitabine, is well tolerated, and warrants evaluation in patients with recurrent breast cancer.