Isolated Intracranial Myeloid Sarcoma Mimicking Malignant Lymphoma: A Diagnostic Challenge and Literature Reviews.

Isolated intracranial myeloid sarcoma (MS) is an unusual variant tumor with few cases reported so far in the medical literature. A 29-year-old woman was admitted to our hospital presenting progressive visual loss in the right eye and weight loss (20 kg) without a previous history of hematological disease (HD). Radiologic evaluation showed the evidence of intracranial mass. Histologically, the resected tumor was composed of a uniform population of primitive cells and primarily misdiagnosed as a T-cell non-Hodgkin's lymphoma (NHL). Chemotherapy with cyclophosphamide, doxorubicin, vinblastine, and prednisone (CHOP) was ineffective. A biopsy and histopathological evaluation were repeated, and immunohistochemical staining revealed the positivity of immature cells to an extensive panel of myeloid markers. These findings were consistent with a diagnosis of MS and bone marrow infiltration. Literature reviews of previous cases were also undertaken.