Ovary tumor
Germ cell tumors
Struma ovarii

Authors: Shahrzad Ehdaivand, M.D. (see Authors page)

Revised: 8 August 2018, last major update December 2012

Copyright: (c) 2002-2018, PathologyOutlines.com, Inc.

PubMed search: Ovarian struma ovarii
Cite this page: Ehdaivand, S. Struma ovarii. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/ovarytumorstruma.html. Accessed August 20th, 2018.
Definition / general
  • Rare monodermal teratoma composed predominantly of mature thyroid tissue
  • May show pathologic changes of thyroid gland including hyperfunctioning; malignancies are usually papillary thyroid carcinoma
  • Associated with mucinous cystadenoma, Brenner tumor, carcinoid tumor and dermoid cyst
Case reports
Gross description
  • Resembles red-brown thyroid tissue but usually multilocular cystic; usually unilateral
Gross images

Images hosted on PathOut server:


Solid and cystic

Reddish brown solid mass

Cystic tumor

Images hosted on other servers:

Partially cystic tumor resembling thyroid

Microscopic (histologic) description
  • Thyroid follicles with colloid; other teratomatous elements may be present
  • Rarely has solid or pseudotubular patterns, microfollicles, abundant eosinophilic cytoplasm, abundant clear cytoplasm or minimal thyroid follicles
Microscopic (histologic) images

Images hosted on PathOut server:

Macrofollicular, microfollicular and solid areas

Solid tubular pattern

Oxyphilic cells arranged in nests

With peripheral formation of lutein cells

Resembling clear cell carcinoma

Cystic tumor


With papillary carcinoma

Images hosted on other servers:

Thyroid-like follicles

Positive stains
  • Thyroglobulin
Molecular / cytogenetics description
Differential diagnosis
  • Metastatic thyroid carcinoma to ovary