title: Signet ring cell adenoma of the thyroid with mucin predominance.
abstract: A 22-year-old male presented with a 1-year history of a right anterior neck mass. He did not have gastrointestinal cancer. Laboratory examination revealed an elevated serum thyroglobulin level of 120 ng/mL. The neck lesion showed poor uptake on 99mTc scan, but enhanced uptake on 201T1 scan. The patient underwent a hemithyroidectomy; the cut surface of the 7 x 3.5 cm lesion was solid and tanned orange. Postoperatively the serum thyroglobulin level decreased to 26 ng/mL. Microscopy of the tumor showed signet ring cells and microfollides, both of which were positive for mucicarmin and alcian Blue. A small percentage of the follicles were positive for thyroglobulin and periodic acid-Schiff. Our literature search detected 18 patients with signet ring cell lesions positive for thyroglobulin, but none had characteristics similar to ours showing predominance of mucin and poor staining for thyroglobulin.
mesh_terms: D000236:Adenoma / Q000378:metabolism* / Q000473:pathology*; D000328:Adult; D006801:Humans; D008297:Male; D009077:Mucins / Q000378:metabolism*; D013954:Thyroglobulin / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000378:metabolism* / Q000473:pathology*