title: Evolution of benign thyroid nodules under levothyroxine non-suppressive therapy.
abstract: BACKGROUND
  Non-suppressive or partially suppressive L-T4 treatment demonstrated to be effective in reducing the volume of the nodules. However, studies with long follow-up are lacking and significant controversy exists regarding the efficacy of non-suppressive L-T4 treatment in benign nodular goiter.
  
  
  OBJECTIVE
  The goal of this study was to determine the evolution of thyroid nodules in subjects treated with a non-suppressive levothyroxine (L-T4) dose, compared to untreated subjects.
  
  
  METHODS
  We followed for a period of 1-9 years the thyroid nodule size in 356 female patients in the age range 19-45 at study entry, of which 201 untreated (Group 0) and 165 treated with a non-suppressive L-T4 dose (Group L-T4).
  
  
  METHODS
  We determined the volume of thyroid nodules by ultrasonography.
  
  
  RESULTS
  The initial mean nodule volume in Group 0 and Group L-T4 was 3.91 ± 6.87 and 4.01 ± 7.35 mL, respectively. Nodule volume increase was inversely correlated to the initial volume. The final volume was slightly higher in untreated than in L-T4 treated subjects (5.37 ± 8.49 and 4.39 ± 6.72 mL). In both groups, the mean of annual fold increase of nodule volume was inversely correlated with the follow-up duration (P < 0.0046), indicating a slower growth as time advances. In the subjects treated with L-T4, the mean annual increase of nodule volume was significantly minor compared to untreated subjects. Concomitant nodules in ten multinodular goiters exhibited totally independent evolution, demonstrating that intranodular factors are more important for the nodule behavior than extra nodular factors.
  
  
  CONCLUSIONS
  Our study demonstrates that the growth of benign thyroid nodules is inversely correlated to their size, benign nodules naturally growth slowly as time advances, and that a chronic treatment with L-T4 at a non-TSH-suppressive dose significantly reduces their growth.
authors.affiliation: Department of Medicine and Surgery, University of Salerno, Via Allende, Baronissi, 84081, Salerno, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Puzziello
authors.forename: Mario
authors.initials: M
authors.lastname: Carrano
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Angrisani
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Marotta
authors.forename: Antongiulio
authors.initials: A
authors.lastname: Faggiano
authors.forename: Pio
authors.initials: P
authors.lastname: Zeppa
authors.forename: Mario
authors.initials: M
authors.lastname: Vitale
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D016606:Thyroid Nodule / Q000097:blood / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D013974:Thyroxine / Q000627:therapeutic use*; D014463:Ultrasonography
chemical_list: D013974:Thyroxine