Unusual leukemic presentation of rhabdomyosarcoma: report of two cases with immunological, ultrastructural and cytogenetical studies
Putti, M.C.; Montaldi, A.; D'Emilio, A.; Sainati, L.; Milanesi, C.; Stella, M.; Zanesco, L.; Basso, G.
Haematologica 76(5): 368-374
1991
ISSN/ISBN: 0390-6078 PMID: 1806439 Document Number: 380391
Background: Bone marrow infiltration occurs rarely at presentation of rhabdomyosarcoma (RMS) or other childbood solid tumors. This possibility leads to misdiagnosis of leukemia and incorrect therapies might be administered. Methods: We report two patients presenting with diffuse bone marrows involvement by neoplastic cells. Initial studies were not consistent with a diagnosis of leukemia and the cases were further studied extensively by indirect immunofluorescence, immunocytochemistry, electron microscopy and cytogenetics. Results: in both cases blast cells were large, poorly differentiated, with immunological reactivity to the anti-desmin antibody. Ultrastructural findings of muscular features and chromosomal translocation t(2;13) (q37;q14) further confirmed the diagnosis of rhabdomyosarcoma of the alveolar subtype. This was then confirmed histologically in one patient. Conclusion: This study stresses the utility of analyzing cases of morphologically undifferentiated marrow blast cells by various techniques, as well as investigating for different types of both hematological and solid neoplasms.