Primary vaginal yolk sac tumor in an 11-month-old girl: a case report

Background: Extragonadal yolk sac tumors are exceedingly rare. This report describes a vaginal yolk sac tumor in an infant to highlight key diagnostic and therapeutic aspects and its inclusion in the differential diagnoses of unexplained vaginal masses. Case presentation: An 11-month-old girl presented with intermittent vaginal bleeding, initially misdiagnosed as a hematoma. Pathological examination confirmed yolk sac tumors. She underwent hysteroscopic resection and six cycles of PEB (bleomycin, etoposide, cisplatin) chemotherapy. No recurrence occurred during the 12-month follow-up. Conclusion: Primary vaginal yolk sac tumors are extremely rare and lack standardized treatment. Surgery combined with PEB chemotherapy proved effective in this case.