Paratesticular Malignant Ectomesenchymoma: An Unrecognized Entity Case Report

Abstract

Saulo Mendoza-Ramírez*, Abril Trejo‐Caballero, Marco Antonio Olvera‐Olvera and Mario Murguia‐Perez*

Malignant ectomesenchymoma is the malignant neoplasm that derives from this tissue; it is characterized by presenting differentiation of neuro-ectodermal and mesenchymal components. The mesenchymal component most of the time is rhabdomyosarcoma. We present the case of an 18-year-old man with a right paratesticular tumor and diffuse pulmonary nodules with probable metastatic activity. The initial diagnosis was a right paratesticular sarcoma with rhabdoid differentiation. By expanding the immunohistochemistry panel, the diagnosis of malignant ectomesenchymoma was confirmed. This tumor is rare and rapidly progressive; few cases have been described in the medical literature.