Metastatic Leptomeningeal Carcinomatosis From Primary Lobular Breast Cancer Found in a Medical School Cadaveric Dissection.

Leptomeningeal carcinomatosis (LC) is an uncommon sequelae of metastatic cancer affecting the pia and arachnoid mater. It has been postulated that recent improvements in cancer patient survival time have increased the frequency of LC and other rare metastatic conditions that patients previously would not have lived long enough to experience. LC carries a universally poor prognosis with a mean survival of between two to four months if treated; however, the recent increase in incidence has allowed for further research into the condition and potential treatments. Options for administering chemotherapy have been limited in the past, but recent developments in surgical chemotherapeutic ports have allowed for intrathecal delivery of drugs like methotrexate without systemic exposure. In fact, innovative delivery systems undergoing clinical trials can deliver these drugs in a metronomic fashion to limit the leukoencephalopathy complications of methotrexate. Primary breast cancer is the most common source of metastatic leptomeningeal lesions, and such a lesion was observed by the authors in the cadaver of a 70-year-old Caucasian female with unspecified breast cancer in a medical school anatomic laboratory. The cause of death was listed as "complication of malignant neoplasm of unspecified site of unspecified female breast." Through this case report, we seek to develop our understanding of this rare metastatic phenomenon and highlight the importance of student cadaveric dissection.