Mar 21, 2016 - Pathology of Struma Ovarii: Single Institutional Experience With 93 ... ovarii is defined as ovarian goiter that is composed either entirely or ...
Surgical Pathology 302 Id: SA59 Pathology of Struma Ovarii: Single Institutional Experience With 93 Cases Shuanzeng Wei, MD, Zubair Baloch, MD, FASCP, Virginia LiVolsi, MD, MASCP, The Hospital of University of Pennsylvania
© American Society for Clinical Pathology
Am J Clin Pathol 2015;144:A302
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Thyroid tissue is a relatively frequent component of mature teratoma, which can be found in 5-20% of cases. Struma ovarii is defined as ovarian goiter that is composed either entirely or predominantly of thyroid tissue (>50%). This definition also encompasses cases of mature teratoma with less than 50% thyroid tissue that contains thyroid malignancy. This case cohort comprising of 115 patients with mature teratoma containing thyroid tissue was identified from the electronic files of our institution (this study was approved by the institutional review board [1989 to 2014]). 13 cases of adenomatous hyperplasia were stained with Ki67 and HBME-1. 4 cases of stromal carcinoid were stained with chromogranin, synaptophysin, calcitonin, thyroglobulin and TTF-1. The teratomas measured 0.141 cm in the greatest dimension (mean 9.2 cm). Various thyroid tissue associated lesions identified in this cohort included papillary thyroid carcinoma (7), highly differentiated follicular carcinoma of ovarian origin (1), strumal carcinoid (5), and struma ovarii (80; 53 cases of thyroid-only struma ovarii). 6 cases showed diffuse adenomatous hyperplasia, and 7 focal had adenomatous hyperplasia. The adenomatous hyperplasia showed no increased expression of Ki67, and focal HBME-1 expression was found in 5 out of 13 hyperplastic lesions. Concurrent lesions with struma ovarii included serous cystadenoma (3), mucinous cystadenomas (4), Brenner tumors (3), ovarian fibroma (1), thecomas (2), and 4 cases with focal hilus cell hyperplasia. There was no tumor recurrence on follow-up (ranging from 2 months to 17 years). In conclusion, papillary thyroid carcinoma and strumal carcinoid are the most common well-differentiated neoplasms/malignancies in struma ovarii; these lesions demonstrate a minimal aggressive clinical behavior.
