“Cellular adenomatoid nodules” of the thyroid: Review of 219 fine‐needle aspirates

Abstract

We reviewed 219 consecutive thyroid aspirates previously diagnosed as "cellular adenomatoid nodule," applying the criteria presented in this paper and reclassifying them as 146 adenomatoid nodules (AN), 31 cellular adenomatoid nodules (CELL-AN), 29 cellular adenomatoid nodules vs. follicular neoplasms (CELL-AN vs. FN), 5 follicular neoplasms (FN), 2 FN of oxyphilic cell type, 4 papillary carcinomas, and 2 chronic lymphocytic (Hashimoto's) thyroiditis. Of the 146 adenomatoid nodules, 14 occurred in multinodular goiters on histologic examination. Of the 31 CELL-AN, five had surgery: two were follicular adenomas, one was papillary carcinoma, and two were multinodular goiters. Of the 29 CELL-AN vs. FN, 11 had surgery: six were follicular adenomas, two were follicular carcinomas, two were multinodular goiters, and one was Hashimoto's thyroiditis. Surgery on four FN showed follicular adenomas (a fifth patient was lost to follow-up). Of the two FN of oxyphilic cell type, one was a multinodular goiter and the other a follicular adenoma with oxyphilic cells. Three of the four papillary carcinomas were confirmed histologically (one patient was lost to follow-up). Of the two cases showing Hashimoto's thyroiditis, one was diagnosed as FN on repeat aspiration and follicular carcinoma at surgery. After review, we identified 40 patients at higher risk of harboring a neoplasm and 31 with cellular adenomatoid nodules. Twenty-five underwent surgery with the above results. In the classification of follicular lesions of the thyroid by FNA, adherence to strict cytologic criteria helps identify those patients who will benefit most from surgery.