Struma ovarii, an ovarian tumor, is diagnosed when >50% of the teratoma is thyroid tissue. Struma ovarii's incidence is <2% of mature teratoma.
Case: We present a rare case report of struma ovarii of a 47-year-old female who presented with incomplete evacuation of bladder and bowel since 2 years. She also complained of dragging pain in abdomen, intermittent radiating to back since last 2/3 years. Her carcino embryonic antigen (CEA) level was 2.56 ng/mL and histologically proved to be struma ovarii.
Results: Single cystic 7 × 4 cm left ovarian mass was diagnosed as struma ovarii.
Conclusion: Struma ovarii though a rare entity should always be kept in mind in a pelvic mass lesion causing discomfort. It is not usually a malignant condition and histopathological examination should be done to rule out struma ovarii.