Microscopically benign thyroid follicles in cervical lymph nodes.Serial section study of lymph node inclusions and entire thyroid gland in 5 cases

Abstract

Microscopically normal thyroid follicles were found in cervical lymph nodes in 5 of 106 autopsies. The inclusions of thyroid follicles were characterized by their microscopic size, location in or adjacent to the capsule, appearance similar to normal follicles, uncrowded, uniform nuclei, and lack of papillarity, psammoma bodies, or fibrous stroma. A carcinoma was found in only 1 of the 5 serially sectioned thyroid glands, and it was on the side opposite to the thyroid-bearing lymph node and was histologically dissimilar to the inclusion. Measurements of nuclei of the inclusions showed a size-distribution more like that of benign than malignant thyroid follicles. The authors support the hypothesis that microscopic inclusions of normal-appearing thyroid follicles in cervical lymph nodes are benign. They never have been associated with progressive thyroid carcinoma and should not be considered an indication for thyroidectomy.