Persistent pleural effusion in an infant with an unusual diagnosis: congenital alveolar rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is a malignant form of neoplasm that originates from skeletal muscle. RMSs can exist anywhere in the human body but are more commonly detected in the neck region and extremities. The alveolar type is one of the subtypes of RMS that has a poor prognosis.