Embryonal rhabdomyosarcoma of the perineum in an adult: a case report

BACKGROUND We report the case of an adult patient with embryonal rhabdomyosarcoma of the perineum admitted to our practice at Joliot Curie Institute in Dakar. It is a rare tumor at this age and has a bad prognosis at this localization. CASE PRESENTATION We describe the case of a 22-year-old African man admitted for a perineal mass that had evolved over 6 months. He complained of tenesmus, obstinate constipation, and dysuria. A clinical examination revealed perineal swelling spread over his anus, scrotum, penis, testicles, and inguinal lymph nodes. A perineal ultrasound and computed tomography scan showed a large mass driving his testicles forward with regional lymph node metastases. An ultrasound-guided biopsy showed embryonal rhabdomyosarcoma on histology and immunohistochemistry, with strong positivity of neural cell adhesion molecule and myogenin while results for cytokeratin AE1/AE3, cluster of differentiation 45, synaptophysin, and chromogranin were negative. Our patient was classified T2N1M1. Outcome was quickly marked by occlusive syndrome and colostomy. Our patient did not opt for chemotherapy and died after 6 months of follow-up. CONCLUSIONS The embryonic RMS of the adult is a rare disease. Despite the sensitivity to chemotherapy and surgery. Localization to perineum remains poor prognosis.