Efficacy and safety of ruxolitinib in regularly transfused patients with thalassemia: results from a phase 2a study

Histiocytic sarcoma (HS) is a rare hematopoietic neoplasm derived from non-Langerhans histiocytic cells of the monocyte/macrophage system that is diagnosed using immunohistochemistry markers, such as CD68, lysozyme, CD4, and CD163, on the tissue biopsies.1 HS can occur in isolation or in association with other hematological neoplasms like non-Hodgkin lymphoma (NHL), myelodysplasia, or acute leukemia.2 HS has variable clinical presentation and outcomes, ranging from localized disease to multiple sites within a single system, to life-threatening disseminated disease (preferentially involving the skin, soft tissue, and gastrointestinal tract).