Nasal embryonal rhabdomyosarcoma with bone marrow metastasis simulating acute leukemia: A case report and review of the literature / Metástasis en médula ósea de rabdomiosarcoma embrionario simulando una leucemia aguda: reporte de un caso y revisión de la literatura

We present a case of a nasal rhabdomyosarcoma (RMS) in a 27-year-old male with epistaxis and nasal obstruction due to a mass, which was subjected to prophylactic tumor embolization. However, histopathological study on the nasal biopsy was impossible due to necrotic changes. As blast cells were present in peripheral blood samples, a bone marrow biopsy was recommended in order to reach a definitive diagnosis. The possibility of an RMS in cases of bone marrow infiltration by a diffuse tumor constituted by small, round, blast-like cells mimicking acute leukemia should be assessed. Immunohistochemical staining in bone marrow biopsy and flow cytometry in aspirate samples may help to establish the diagnosis (CD45 negativity and CD56 positivity) and cytogenetic studies can be useful in identifying a RMS subtype. When clinically possible, it is desirable to await the results of the tumor immunophenotype and those of the primary mass or bone marrow biopsy to avoid possible errors of diagnosis and treatment

Se presenta el caso de un rabdomiosarcoma (RMS) en un varón de 27 años de edad con cuadro de epistaxis y obstrucción por masa nasal, que fue sometido a embolización tumoral profiláctica. El estudio en sangre periférica, fundamentalmente por la detección de células de apariencia blástica, recomendó biopsia de médula ósea que fue determinante para el diagnóstico, debido a que la embolización tumoral en la biopsia nasal, invalidó por cambios necróticos su estudio histopatológico. Se debe evaluar la posibilidad diagnóstica de un RMS, en casos de infiltración de médula ósea por un tumor difuso constituido por células pequeñas, redondas y similares a blastos que imitan una leucemia aguda. La tinción inmunohistoquímica en la biopsia de médula ósea y la citometría de flujo en muestras de aspirado, pueden ayudar a establecer el diagnóstico (negatividad CD45 y positividad CD56) y los estudios citogenéticos pueden ayudar a diferenciar el subtipo de RMS. Cuando sea clínicamente posible, se debe esperar a los resultados del inmunofenotipo celular del tumor y los de la masa primaria o la biopsia de la médula ósea, para así evitar posibles errores de diagnóstico y tratamiento

Nasal embryonal rhabdomyosarcoma with bone marrow metastasis simulating acute leukemia: A case report and review of the literature.

We present a case of a nasal rhabdomyosarcoma (RMS) in a 27-year-old male with epistaxis and nasal obstruction due to a mass, which was subjected to prophylactic tumor embolization. However, histopathological study on the nasal biopsy was impossible due to necrotic changes. As blast cells were present in peripheral blood samples, a bone marrow biopsy was recommended in order to reach a definitive diagnosis. The possibility of an RMS in cases of bone marrow infiltration by a diffuse tumor constituted by small, round, blast-like cells mimicking acute leukemia should be assessed. Immunohistochemical staining in bone marrow biopsy and flow cytometry in aspirate samples may help to establish the diagnosis (CD45 negativity and CD56 positivity) and cytogenetic studies can be useful in identifying a RMS subtype. When clinically possible, it is desirable to await the results of the tumor immunophenotype and those of the primary mass or bone marrow biopsy to avoid possible errors of diagnosis and treatment.