Leptomeningeal metastasis

Leptomeningeal cancer (also called leptomeningeal carcinomatosis, leptomeningeal disease (LMD), leptomeningeal metastasis, neoplastic meningitis, meningeal metastasis and meningeal carcinomatosis) is a rare complication of cancer in which the disease spreads from the original tumor site to the meninges surrounding the brain and spinal cord, causing them to become inflamed. The term leptomeningeal (from the Greek lepto, meaning “fine” or “slight”) describes the thin meninges, the arachnoid and the pia mater, between which the cerebrospinal fluid is located. The disorder was originally reported by Eberth in 1870. Leptomeningeal cancer (also called leptomeningeal carcinomatosis, leptomeningeal disease (LMD), leptomeningeal metastasis, neoplastic meningitis, meningeal metastasis and meningeal carcinomatosis) is a rare complication of cancer in which the disease spreads from the original tumor site to the meninges surrounding the brain and spinal cord, causing them to become inflamed. The term leptomeningeal (from the Greek lepto, meaning “fine” or “slight”) describes the thin meninges, the arachnoid and the pia mater, between which the cerebrospinal fluid is located. The disorder was originally reported by Eberth in 1870. It occurs with cancers that are most like to spread to the central nervous system. The most common cancers to include the leptomeninges are breast cancer, lung cancer, and melanomas because they can metastasize to the subarachnoid space in the brain which offers a hospitable environment for the growth of metastatic tumor cells. Individuals whose cancer has spread to an area of the brain known as the posterior fossa have a greater risk of developing a leptomeningeal cancer. Leptomeningeal disease is becoming more evident because cancer patients are living longer and many chemotherapies cannot reach sufficient concentrations in the spinal fluid to kill the tumor cells. In the United States, 1–8% of cancer patients are diagnosed with leptomeningeal disease, with approximately 110,000 cases per year. The exact incidence of leptomeningeal disease is difficult to determine, since gross examination at autopsy may overlook signs of leptomeningeal disease, and microscopic pathological inspection may be normal if the seeding is multifocal or if an unaffected area of the CNS is examined. Leptomeningeal carcinomatosis occurs when the cancer cells invade and proliferate in the cerebrospinal fluid. and spread throughout the central nervous system. The metastatic tumor cells grows either attached to the pia mater covering the brain and spinal cord or floating unattached to the subarachnoid space. Tumors of diverse origins and hematologic cancers may spread to this space.