Rare Adult Presentation of Embryonal Rhabdomyosarcoma: A Case Analysis

Abstract Rhabdomyosarcoma (RMS) is a malignant tumor of striated muscle origin, derived from primitive mesenchymal cells that retain the capacity for skeletal muscle differentiation. Nearly 90% of cases are diagnosed in individuals under the age of 25, with a slightly lower prevalence among people of Asian descent compared to Black or White populations. The most common sites of origin include the head and neck, followed by the genitourinary tract, extremities, and trunk.Rhabdomyosarcoma is classified into five major histologic subtypes: embryonal, alveolar, botryoid, spindle cell embryonal, and anaplastic. Embryonal rhabdomyosarcoma, the most common subtype in children, accounts for approximately 60% of all cases.Embryonal rhabdomyosarcoma is associated with a loss of genetic material from the short arm of chromosome 11 (11p15), suggesting the presence of a tumor suppressor gene in this region, though the exact gene responsible remains unidentified.