WOFAPS 2025 8th World Congress of Pediatric Surgery

Leecarlo Millano Lumban Gaol ¹, Yuliana Saraswati Kusuma Prabaningrum ¹, Aulia Fitri Swity ², Gibran Kashogi ³, Yohanes Firmansyah ⁴, Bryan Anna Wijaya ⁴, Fiona Valencia Setiawan ⁴

¹ Department of Surgery, Pediatric Surgery Division, Tarakan General Hospital, Central Jakarta, Indonesia
² Department of Pediatrics and Child Health, Tarakan General Hospital, Central Jakarta, Indonesia
³ Department of Surgery, Pediatric Surgery Division, Cibinong General Hospital, West Java, Indonesia
⁴ Faculty of Medicine Tarumanagara University, Jakarta, Indonesia

Introduction:Rhabdomyosarcoma (RMS) is a malignant neoplasm of mesenchymal origin.Perianal and perineal RMS (PRMS) are rare tumors that are often misdiagnosed and have a poor prognosis.Embryonal rhabdomyosarcoma (ERMS),the most common histological subtype, predominantly affects children under 10 years of age.However,its occurrence in neonates and early infancy is rare,comprising only 0.4–2% of reported cases.In this population,ERMS may mimic benign perineal lesions,complicating early recognition and diagnosis.

Case Presentation:A two-month-old female infant,born at term via cesarean section to a mother with gestational diabetes mellitus,presented with a perineal mass noted since birth.The family resided adjacent to a gas processing facility during pregnancy.The mass had increased in size,accompanied by urinary straining and decreased activity.Gynaecological examination showed abnormal vaginal tissue protruding through the vagina introitus and anus in the form of a "grape bunch" appearance which also resembled cauliflower,measuring approximately 10 cm in diameter.The mass is pale pink,soft to firm on palpation,suspected to contain fluid,and malodorous with surface ulceration and contact bleeding.Laboratory results showed anemia (Hb 8.6 g/dL),leukocytosis (13.64 × 10³/µL),thrombocytosis (758 × 10³/µL),and hypoalbuminemia (2.7–3.4 g/dL).Peripheral blood smear revealed microcytic, hypochromic anisopoikilocytosis with target cells.Viral serologies for CMV and HSV types I and II were non-reactive.Surgical excision of the mass was performed.Histopathological analysis showed round to spindle-shaped tumor cells with hyperchromatic nuclei.Immunohistochemical staining was positive for vimentin,desmin,and myogenin,confirming the diagnosis of embryonal rhabdomyosarcoma.Bone marrow aspiration and cerebrospinal fluid analysis showed no evidence of metastasis.The patient was initiated on a chemotherapy regimen consisting of ifosfamide,vincristine,and dactinomycin.

Conclusion:Embryonal rhabdomyosarcoma,although rare in early infancy,should be considered in the differential diagnosis of congenital perineal masses.Accurate diagnosis requires comprehensive clinical, histopathological, and immunohistochemical evaluation to guide timely and appropriate treatment.