Which benefit from adding gemcitabine to vinorelbine in elderly (≥70 years) women with metastatic breast cancer?: Early interruption of a phase II study

Background: Since vinorelbine and gemcitabine are both active in breast cancer with moderate toxicity, in 2002 we started a phase II trial with a combination regimen in elderly patients. Patients and methods: To evaluate complete plus partial response rates and toxicity of first-line vinorelbine 25 mg/m(2) plus gemcitabine 1000 mg/m(2) on days 1 and 8, every 3 weeks, in women >= 70 years with advanced breast cancer and measurable lesions. All patients underwent multidimensional geriatric assessment before enrollment. A two-step design was applied, and the trial would be completed if an overall response rate >= 30% was obtained with a grade 3-grade 4 (G3-G4) toxicity rate <= 25% (excluding neutropenia) in the first step. Results: Twelve eligible patients had a median age of 74 years. At MGA, eight patients were fit, three vulnerable, one frail due to major depression; only two patients had G3 comorbidities according to Cumulative Illness Rating Scale-Geriatric. Seventy-five percent of patients had visceral disease. We obtained only one partial remission (11.1%) and six stabilizations of disease in nine assessable patients, with a time to progression of 3 months. Three patients (25%) experienced G3 neutropenia, and three patients (25%) developed G3 anemia (one patient) and G3 gastrointestinal toxicity (two patients). Conclusions: The promising response rates obtained with this combination by other authors could not be confirmed in our small cohort of older women with breast cancer, therefore the trial was prematurely terminated. We do not recommend the co-administration of gemcitabine to vinorelbine in women >= 70 years outside the setting of controlled clinical trials.