Gemcitabine as single-agent therapy in the management of advanced breast cancer.

Many active cytotoxic agents exist for breast cancer therapy, and numerous combination chemotherapy regimens are derived from them. Creating these combinations is sometimes empirically motivated by non-overlapping toxicities or the expectation of non-cross resistance. Yet, there is usually no absolute division of these aspects among cytotoxic agents, and the median survival for patients with metastatic breast cancer has not been dramatically prolonged by this approach. When the outcome of treatment is palliation rather than cure, it becomes paramount to optimize the dynamic equilibrium between chemotherapy-induced side effects and the benefits attributable to relief of cancer-related symptoms. To this end, several recent clinical trials have evaluated the novel nucleoside analog gemcitabine (Gemzar) as single-agent therapy for advanced breast cancer. This article reviews these trials.