title: Histologic trends in thyroid cancer 1969-1993: a clinico-pathologic analysis of the relative proportion of anaplastic carcinoma of the thyroid.
abstract: BACKGROUND
  It was observed that new presentations of anaplastic carcinoma of the thyroid had become infrequent in the last two decades.
  
  
  METHODS
  All cases of thyroid cancer seen at our centre between 1969-1993 (n = 2921) were classified as papillary 49%, follicular 34%, medullary 7.5%, anaplastic 4.7%, and other 4.8%. The total number of thyroid cancers show a 3.5-fold rise.
  
  
  RESULTS
  The differentiated thyroid cancers show a significant rising trend as against the relative proportion of anaplastic carcinoma, which shows a significant decline (P = 0.002). Clinicopathologic data on 124 patients of anaplastic carcinoma revealed 50% patients had either long-standing goitres, previous thyroid abnormalities, or associated differentiated thyroid carcinoma on histology.
  
  
  CONCLUSIONS
  The decline in the relative proportion of anaplastic carcinoma may in part be explained by the clinicopathologic findings or it may be attributed to histological reclassification.
authors.affiliation: Department of Surgical Oncology, Tata Memorial Hospital, Parel, Bombay, India.
authors.forename: S
authors.initials: S
authors.lastname: Agrawal
authors.forename: R S
authors.initials: RS
authors.lastname: Rao
authors.forename: D M
authors.initials: DM
authors.lastname: Parikh
authors.forename: H K
authors.initials: HK
authors.lastname: Parikh
authors.forename: A M
authors.initials: AM
authors.lastname: Borges
authors.forename: M B
authors.initials: MB
authors.lastname: Sampat
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000453:epidemiology / Q000473:pathology*; D018276:Carcinoma, Medullary / Q000453:epidemiology; D002291:Carcinoma, Papillary / Q000453:epidemiology; D018265:Carcinoma, Papillary, Follicular / Q000453:epidemiology; D016009:Chi-Square Distribution; D005260:Female; D006042:Goiter / Q000453:epidemiology / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D013964:Thyroid Neoplasms / Q000453:epidemiology / Q000473:pathology*