adenomatoid nodule

adenomatoid nodule (thyroid)

One or more circumscribed but unencapsulated clusters of follicular cells that are morphologically similar to the surrounding thyroid tissue, which may arise in a background of Hashimoto’s thyroiditis and be confused with a true adenoma.
References in periodicals archive ?
Follicular carcinoma must be distinguished from follicular adenoma, adenomatoid nodules, the follicular variant of thyroid papillary carcinoma, medullary carcinoma, and other clear-cell tumors (parathyroid adenoma/carcinoma) or metastatic renal cell carcinoma.
Fortunately, the vast majority of these nodules are benign (adenomas and adenomatoid nodules of multinodular goiters); approximately 2% to 12% are found to represent malignancy upon further work-up.
Metastatic deposits are identified at a higher frequency in abnormal glands--that is, those with adenomatoid nodules, thyroiditis, and follicular neoplasms.
Many neoplasms are considered in the differential diagnosis, but the principal ones are follicular adenoma, follicular carcinoma, and medullary carcinoma; nonneoplastic considerations are diffuse hyperplasia (Graves' disease) and adenomatoid nodules.