title: Natural course of benign thyroid nodules in a moderately iodine-deficient area.
abstract: OBJECTIVE
  Few studies using ultrasonographic evaluation have addressed the natural course of benign thyroid nodules. In this study, we present the long-term analysis of benign, untreated thyroid nodules in a moderately iodine-deficient area.
  
  
  METHODS
  We collected the retrospective data for 531 nodules in 420 patients followed by ultrasonography for a mean time period of 39.7 +/- 27.8 months (range 12-168 months).
  
  
  RESULTS
  When we considered significant nodule size decrease criteria as decreases in nodule volume of at least 15% and 30%, we found that 33.1% and 20.7% of thyroid nodules decreased in size, respectively. Using the criteria of a greater than 15% and 30% increase in volume showed that 32% and 24.1% increased in size, respectively. A logistic regression analysis using mixed models to predict thyroid nodule growth (volume change > or = 15%), including age, TSH, sex and time between evaluations, failed to predict nodule growth. Only hypoechoic echo pattern remained as a statistically significant predictor of growth.
  
  
  CONCLUSIONS
  In 40 months' follow-up, we found that benign thyroid nodules exhibited a mostly favourable clinical natural course. One-third of benign thyroid nodules showed continuous growth, one-third remained unchanged, and the other third decreased in size.
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Ankara University School of Medicine, Ankara, Turkey.
authors.forename: Murat Faik
authors.initials: MF
authors.lastname: Erdogan
authors.forename: Alptekin
authors.initials: A
authors.lastname: Gursoy
authors.forename: Gurbuz
authors.initials: G
authors.lastname: Erdogan
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D018450:Disease Progression; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007455:Iodine / Q000172:deficiency*; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D012737:Sex Factors; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000209:etiology; D013972:Thyrotropin / Q000097:blood; D019371:Topography, Medical; D014421:Turkey; D014463:Ultrasonography
chemical_list: D013972:Thyrotropin; D007455:Iodine