summary Histiocytomas, also known as benign fibrous histiocytomas, are extremely rare, benign histiocytic lesions of bone. Patients typically present with regional pain and swelling. Diagnosis is made with radiographs that show a characteristic lytic lesion with a sclerotic border and biopsy with histology showing spindle cells and foamy macrophages in storiform pattern. Treatment is usually curettage and bone grafting. Epidemiology Incidence extremely rare presentation Symptoms pain and swelling Imaging Radiographic characteristics lytic lesion with sclerotic border Histology Characteristic findings spindle cells foamy macrophages storiform pattern (helicopter in wheat field) Treatment Operative curettage and bone grafting Prognosis Recurrence rare