Local Control of Primary Dural Central Nervous System Lymphoma Achieved With Radiotherapy.

Primary central nervous system lymphomas (PCNSL) are extranodal non-Hodgkin's lymphomas (NHL) confined to the brain, leptomeninges, eyes, or spinal cord. Primary leptomeningeal lymphoma (PLML), without parenchymal involvement, synchronous cerebrospinal, or systemic disease is rare. The estimated incidence of PLML is 7% of all PCNSL, which in turn accounts for about 2% of all primary brain tumors and 0.8% of all lymphomas. The incidence of PCNSL in Western countries is approximately five cases per million inhabitants per year, and less than 5% of all primary tumors of the central nervous system (CNS), although it is worth mentioning that the incidence seems to be increasing. The largest series of cases reported in the medical literature collect information from no more than nine patients; in these series, the median age at diagnosis is 57 years; in general, all patients present with cerebrospinal fluid alteration, and the median overall survival rate is close to eight months. With our case series, we aim at sharing the experience of four patients diagnosed and treated at the National Cancer Institute between 2010 and 2020, establishing a correlation of the clinical, imaging, and histopathological presentation, the response to treatment based on radiotherapy and chemotherapy, and the clinical outcomes reported in the medical records.