Thyroid Atypia/Follicular Lesion of Undetermined Significance: Attitudes towards the Diagnosis of Bethesda System III Nodules

Acta Cytol. 2017;61(1):21-26. doi: 10.1159/000452156. Epub 2016 Nov 17.

Abstract

Objectives: To review our institutional experience and to analyze the clinical decisions made after a cytological diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS).

Study design: This is a retrospective review of all thyroid fine-needle aspiration (FNA) cytologies performed in the Hospital Clínico San Carlos (Madrid) between 2010 and 2014.

Results: One hundred thirty thyroid FNA were categorized as AUS/FLUS (5%). One hundred six (81.5%) patients were women, and the mean age was 59 years. In 61 patients a repeated FNA was performed (46%). Fifty-five nodules were treated surgically (42.3%), with a histopathological diagnosis of nodular hyperplasia in 36 cases (65%), adenoma in 11 (20%), and carcinoma in 8 (14.5%). In the group of nonsurgical patients (n = 75), a repeated FNA was performed in 43 (57.3%) cases. We found no statistically significant association between sex or age and clinical management (p = 0.13 and p = 0.31, respectively).

Conclusions: Clinical management after an AUS/FLUS FNA diagnosis is erratic and does not match standardized management protocols. The AUS/FLUS classification has not led to new diagnostic tests in a relevant percentage of patients. The implementation of consensual institutional strategies could lead to better management of these cases.

MeSH terms

  • Adenocarcinoma, Follicular / diagnosis*
  • Adenocarcinoma, Follicular / pathology
  • Adenoma / diagnosis*
  • Adenoma / pathology
  • Adult
  • Aged
  • Aged, 80 and over
  • Biopsy, Fine-Needle
  • Carcinoma / diagnosis*
  • Carcinoma / pathology
  • Diagnosis, Differential
  • Female
  • Humans
  • Male
  • Middle Aged
  • Retrospective Studies
  • Thyroid Gland / pathology
  • Thyroid Neoplasms / diagnosis*
  • Thyroid Neoplasms / pathology
  • Thyroid Nodule / diagnosis*
  • Thyroid Nodule / pathology