Special Clinical Characteristics of Struma Ovarii- Two Unique Cases Report

Introduction: Struma ovarii is a rare type of ovarian cystic teratoma with composed of predominantly thyroid tissue. It occurs between 30-50 years of age, usually in unilateral ovary. Struma ovarii rarely occurs before puberty and is growing slowly. Hereby we reported 2 cases in which one case with combined cystic teratoma in one side and Struma ovarii in contralateral side of ovary, the second case with Struma ovarii occurs at age of 16 then growing tremendously with in only 8 years.

Methods: A retrospective study of the data bases of community hospitals in Taipei city during 2014 -2016 were included. Two cases with a histological diagnosis of Struma ovarii who had undergone surgery were identified.

Patients

Case 1: A 29-year-old female patient presented with recently irregular vaginal bleeding, abdominal distention and low abdominal palpable mass. Her past history revealed right ovarian cystic teratoma underwent laparoscopic removal of tumor at age of 16. CT scan revealed the contralateral ovarian calcified tumor (10cm x 7.5cm) with heterogenous mass with solid and cystic components. Post-operative finding was left ovarian cyst with smooth surface and gelatinous material content.

Case 2: A 24-year-old single patient presented with amenorrhea and abdominal distention. She had history of right ovarian simple cyst (4.2cm x 3.2cm) at age of 16. She came after 8 years; the physical examination found the ovarian tumor growing to a tremendous size. CT scan showed a homogenous cystic tumor 25.8cm x 25.7cm x 16cm with a few heterogenous enhanced nodules. Post-operative finding of big left ovarian cystic tumor, glistening surface with gelatinous material, few septations was observed.

All two patient’s pre-operative diagnosis were dermoid tumors with suspected ovarian malignancy.

Conclusion: Due to the rarity of Struma ovarii its natural history, growth pattern and treatment strategy is not yet cleared. Clinical presentation and symptoms of Struma ovarii are vary, image studies are often suspected of ovarian carcinoma. Preoperative diagnosis is important. The best management plan should be individualized. More cases reports are needed.

Keywords: Cystic teratoma; Fast growing Struma ovarii