Pancytopenia and fulminant disseminated intravascular coagulation in a 68-year-old woman suggested an acute hematologic malignancy. However, cytogenetic analysis on a bone marrow sample revealed a near-tetraploid karyotype with an isochromosome 1q and a translocation (2;13) (q35;q14), which was suggestive of an alveolar rhabdomyosarcoma (ARMS). This diagnosis was subsequently confirmed by indirect immunohistochemistry. ARMS has not yet been observed in a patient of this age. Thus, our case underlines the importance of cytogenetics, to establish an a priori unexpected tumor diagnosis.