Source:http://linkedlifedata.com/resource/umls/id/C0038478
MSH: A rare teratoid tumor of the ovary composed almost entirely of thyroid tissue, with large follicles containing abundant colloid. Occasionally there are symptoms of hyperthyroidism. 5-10% of struma ovarii become malignant, the only absolute criterion for which is the presence of metastasis. (Dorland, 27th ed; Segen, Dictionary of Modern Medicine, 1992),NCI: An ovarian mature teratoma characterized by the presence of aberrant thyroid tissue. The aberrant thyroid tissue shows morphologic changes identical to thyroid adenoma or carcinoma. Patients may present with abdominal mass and unusual symptoms due to thyrotoxicosis, or Meigs syndrome (ascites and pleural effusion).