Long-term clinical response in leptomeningeal metastases from breast cancer treated with capecitabine monotherapy: a case report.

Brain and leptomeningeal metastases from breast cancer carry a poor prognosis and are often less responsive to systemic therapy. It is often thought that systemic therapy has a minimal role in the management of central nervous system (CNS) metastases because of the impermeability of the blood-brain barrier. However, treatments directed to the CNS such as radiation or intrathecal chemotherapy are not effective in managing concurrent non-CNS metastases. We report the long-term control of a woman receiving capecitabine with brain and leptomeningeal metastases. After 3.7 years of capecitabine therapy after whole-brain radiation, the patient remains without neurologic symptoms or deficits, has no evidence of disease on neuroimaging studies, but has a persistent positive cytology. This case report demonstrates that, in principle, systemic therapy can provide long-term complete responses for some patients with CNS metastases. The significance of persistent circulating tumor cells in the CNS in patients without evidence of disease is unclear but should be investigated further.