title: Fine-needle aspiration of mucin-producing thyroid tumors.
abstract: OBJECTIVE
  Mucin-producing thyroid tumors are extremely rare. Nonetheless, we have encountered three such cases in fine-needle aspiration. We report the cytologic and histologic findings and review the literature.
  
  
  METHODS
  Cytologic features were studied on direct smears using Romanovsky stain to detect background substance and Papanicolaou stain to analyze nuclear and cytoplasmic features. The cytologic features were correlated with histology. Mucin was demonstrated by mucicarmine, Alcian Blue/PAS, and Alcian Blue (pH 2.5).
  
  
  RESULTS
  The cytologic features related to mucin include: (1) thick luminal mucin globules and signet ring cells aspirated from an 83-year-old woman with a 3-cm signet ring cell follicular adenoma, (2) abundant fluffy mucin containing signet ring cells in cohesive fragments aspirated from a 75-year-old man with the bilateral signet ring cell follicular variant of papillary carcinoma, which is the first case in the English literature, and (3) abundant thin mucoid mucin aspirated from the lymph node of an 86-year-old woman with a 5-cm mucinous poorly differentiated thyroid carcinoma.
  
  
  CONCLUSIONS
  The occurrence of mucin in thyroid fine-needle aspiration does not necessarily indicate metastasis, and the presence of mucin in cervical lymph nodes does not exclude the thyroid gland as a possible primary.
authors.affiliation: Department of Pathology and Laboratory Medicine, New York Presbyterian Hospital/Weill Cornell Medical Center, New York, N.Y., USA. Mailgry2001@med.cornell.edu
authors.forename: Grace C H
authors.initials: GC
authors.lastname: Yang
authors.forename: Theresa
authors.initials: T
authors.lastname: Scognamiglio
authors.forename: William I
authors.initials: WI
authors.lastname: Kuhel
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000175:diagnosis / Q000473:pathology*; D000236:Adenoma / Q000175:diagnosis / Q000473:pathology*; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle; D002277:Carcinoma / Q000175:diagnosis / Q000473:pathology*; D002291:Carcinoma, Papillary; D018279:Carcinoma, Signet Ring Cell / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D008297:Male; D009077:Mucins / Q000032:analysis* / Q000096:biosynthesis; D017410:Practice Guidelines as Topic; D000077273:Thyroid Cancer, Papillary; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000473:pathology*
chemical_list: D009077:Mucins