Alveolar Paratesticular Rhabdomyosarcoma in an Adult Patient With PAX3-FOXO1 Fusion and Unfavorable Evolution.

Rhabdomyosarcomas, malignant mesenchymal tumors of skeletal striated muscle tissue cells, are usually rare in adults. However, when they occur in this population, the prognosis is usually poor, especially if the condition is associated with molecular factors such as the PAX3-FOXO1 fusion. Here, We report a case of paratesticular alveolar rhabdomyosarcoma in an adult patient who initially complained of increased scrotal volume for two years and presented with a PAX3-FOXO1 fusion. This emphasizes the dire prognosis of the disease, reinforcing the need for thorough and directed diagnostic efforts.