Primary leptomeningeal histiocytic sarcoma in a patient with a good outcome: a case report and review of the literature

INTRODUCTION: Histiocytic sarcoma is a rare neoplasm with few cases reported in the literature of which some were diagnosed in animals. This neoplasm arises from abnormal reticuloendothelial system cell proliferation of histiocytes and has an aggressive behavior especially if located in the central nervous system. We present the first case of a patient with histiocytic sarcoma that involved the meninges and had a good course after multidisciplinary treatment. CASE PRESENTATION: Our patient was a 41-year-old Caucasian woman with no previous history of disease who started with systemic symptoms such as headache and chills. Magnetic resonance imaging with gadolinium contrast of the brain suggested a mass 1.5×2cm in diameter in the temporal lobe with a non-uniform vasogenic edema. This lesion was implanted in the meninges and surgery was the first treatment. The histological findings revealed a histiocytic sarcoma. The patient received concomitant chemoradiotherapy after surgery with good tolerance and currently lives without disease. CONCLUSION: Although histiocytic sarcomas in the brain present an unusual location and have a poorer prognosis, we have identified the first primary leptomeningeal histiocytic sarcoma with a disease-free survival greater than 3 years following multidisciplinary treatment with surgery and chemotherapy and radiotherapy.