High-dose intrathecal trastuzumab for leptomeningeal metastases secondary to HER-2 overexpressing breast cancer

Abstract

We are facing an increasing incidence of brain and leptomeningeal metastases (LM) during the history of patients with HER-2-overexpressing breast cancer. This clinical issue is due to the neurotropism of HER-2-overexpressing breast cancer cells, combined with the high antitumoral activity of systemic administrations of trastuzumab but without preventive effect in the brain and leptomeninges. Indeed, trastuzumab is a monoclonal IgG1 antibody to HER-2, which poorly reaches the cerebrospinal fluid (CSF) when given i.v. [1]. Intrathecal (IT) administration of trastuzumab has been scarcely tested [2–5] in patients with LM occurring after a systemic complete remission induced by i.v. trastuzumab (Table 1). Therefore, we eagerly need to accumulate experience on the use of IT trastuzumab in this setting. We report here the case of a patient with HER-2-overexpressing breast cancer who developed LM. We obtained a long-lasting control of the disease progression using high doses of IT trastuzumab.