Giant Paraovarial Cystadenoma in An Adolescent: Case Report and Literature Review

Background: Paraovarian cysts are uncommon adnexal formations arising from paramesonephric, mesonephric, or mesothelial remnants, accounting for 4–7% of adnexal masses in children and adolescents. Giant paraovarian cysts exceeding 15–20 cm are exceptionally rare in this age group and present significant diagnostic challenges. Case Presentation: We report the case of a 16-year-old girl presenting with intermittent abdominal pain and distension. Imaging revealed a large unilocular cystic lesion measuring 18 × 6.6 × 20 cm, extending from the pelvis to the L3 vertebral level and compressing adjacent pelvic structures. Due to the cyst’s size and uncertain nature, an open lower midline laparotomy was performed. Intraoperatively, a right paraovarian cyst was identified and excised en bloc without complications. Histopathological analysis confirmed a benign paraovarian cyst with focal micropapillary serous cystadenoma features. The postoperative course was uneventful, and the patient made a full recovery. Discussion: Preoperative differentiation between ovarian and paraovarian cysts is challenging due to overlapping clinical and imaging features. While laparoscopy is generally preferred, laparotomy may be indicated for large cysts with uncertain etiology or potential malignancy. Conclusion: This case highlights the rarity of giant paraovarian cysts in adolescents and underscores the importance of thorough imaging evaluation and individualized surgical planning to ensure accurate diagnosis and optimal outcomes.