Unusual case of pelvic hydatid cyst of broad ligament mimicking an ovarian tumour

INTRODUCTION: The diagnosis of hydatid cyst in female genital tract is rare and difficult. A high degree of clinical suspicion is needed for pre-operative investigations to exclude hydatid cyst of female pelvis. The objective of this presentation is to highlight a pelvic hydatid cyst that presented as an ovarian tumour. CASE PRESENTATION: A 22-year-old female, presented with constipation and haematuria with acute urinary retention. On examination, a mass measuring 15×13 cm was palpable in the left iliac region reaching up to the umbilicus. It was smooth, movable and non-tender and a provisional diagnosis of ovarian teratoma was made pre-operatively. At laparotomy, a cystic mass was found attached to the broad ligament, excised, and a frozen section was sent for histopathology. Gross features were consistent with hydatid cyst; the cystic wall was white and there were multiple small thin-wall daughter cysts. Microscopic diagnosis with paraffin sections showed cystic lesions with laminated wall and scolices in the daughter cyst. Indirect haemagglutination test for specific antibodies was positive (128 IU). The patient responded well to surgical excision followed by albendazole administration. CONCLUSION: This case highlights the fact that a pelvic hydatid disease may resemble neoplastic ovarian cyst, clinically and radiologically. The possibility of pelvic hydatid disease should be included, in endemic areas where differential diagnosis of cystic ovarian lesions is needed, so that the patient can be managed accordingly.