Intra-operative consult for cystic struma ovarii—An experience in an academic medical center: A study of 53 cases over 21 years

Struma ovarii often escapes recognition during intraoperative consultation because of its rarity, subtle characteristic gross appearance, and lack of clinical suspicion. An intraoperative diagnosis of benign struma ovarii enables the general gynecologic surgeon to continue the planned surgery. However, a diagnosis of malignnancy in a struma ovarii would alter the course of surgery with the involvement of a gynecologic oncology surgeon. We present here that our experience with intraoperative consultation for preoperatively undiagnosed struma ovarii presenting as an adnexal cystic or solid mass at our teaching hospital. Fifty-three cases of struma ovarii, 5.2% of all cystic teratoma of the same period, were diagnosed between January 1991 and March 2011. All intraoperative consultation reports, gross descriptions and final pathology reports were reviewed. The H&E stained slides and in selected cases, immunohistochemistry stained slides, were reviewed. Of the 53 cases of struma ovarii, intraoperative consultation was requested on 48 cases. Frozen section was done on 24 cases and only gross examination was felt appropriate in remaining 24 cases. 83% cases were diagnosed when a frozen section was done. None of the remaining 24 cases were recognized as struma by gross inspection. Our findings reveal that in a large number of cases the diagnosis of struma ovarii remained unrecognized during intraoperative consultation, indicating its often subtle/deceptive gross morphologic appearance. However, the purpose of the intraoperative consultation was served, as appropriate information was provided to the surgeon to guide the surgical management.