title: Systemic rhabdomyosarcoma presenting as leukemia: case report with ultrastructural study and reviews.
abstract: A 20-year-old white male was initially suspected clinically and pathologically of having an acute lymphoblastic leukemic process because of fatigue, severe anemia, thrombocytopenia, a leuko-erythroblastic peripheral blood picture, and a diffusely infiltrated bone marrow. Subsequent review of the bone marrow material indicated cytologic features consistent with either an embryonal, undifferentiated small cell mesenchymal malignancy or reticulo-endothelial malignancy. Ultimately, the electron microscopic (EM) study of the tumor proved to be diagnostic of rhabdomyosarcoma. An extensive search for a primary site of rhabdomyosarcoma did not show any lesion, although the genitourinary region was clinically suspected. The clinical course was a rapidly downhill one with extensive bone and CNS involvement. The patient died 5 months later. An autopsy permit was not obtained. This case emphasizes the occasional tendency of rhabdomyosarcoma to masquerade as a hematopoietic malignancy at the time of presentation and the usefulness of EM study in confirming a diagnosis.
authors.forename: M
authors.initials: M
authors.lastname: Huntrakoon
authors.forename: L A
authors.initials: LA
authors.lastname: Callaway
authors.forename: G G
authors.initials: GG
authors.lastname: Vergara
mesh_terms: D000328:Adult; D000740:Anemia / Q000175:diagnosis / Q000473:pathology; D001707:Biopsy, Needle; D001853:Bone Marrow / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D007945:Leukemia, Lymphoid / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008854:Microscopy, Electron; D012208:Rhabdomyosarcoma / Q000175:diagnosis* / Q000473:pathology; D012867:Skin / Q000473:pathology