Role of galectin-3 immunodetection in the cytological diagnosis of thyroid cystic papillary carcinoma

Eur J Endocrinol. 2002 Oct;147(4):515-21. doi: 10.1530/eje.0.1470515.

Abstract

Objective: Cystic thyroid lesions can harbour an occult papillary carcinoma, which fine needle aspiration (FNA) biopsy may fail to detect. Recently, new markers such as galectin-3 lectin have been proposed to distinguish benign from malignant thyroid lesions of follicular origin. The aim of this study was to assess the role of galectin-3 immunodetection in a series of FNA cytological samples of benign and malignant thyroid cystic nodules.

Methods: We retrospectively analysed galectin-3 expression by immunoperoxidase staining on 32 cytological paraffin-embedded samples of cystic papillary carcinoma and on 12 samples of benign cysts, both obtained by FNA biopsy. Specificity, sensitivity, positive/negative predictive values, and accuracy of standard cytological examination and galectin-3 immunodetection were assessed.

Results: Among cystic papillary carcinomas, 29 of 32 samples were galectin-3 positive, whereas standard FNA cytology made a correct diagnosis in only 25 of 32 samples. All the benign cysts were negative for galectin-3. In comparing the sensitivity and specificity of the two methods, it appeared that both had a 100% specificity, whereas the sensitivity of cytological examination alone was 75% versus 89.3% obtained by galectin-3 immunohistochemistry.

Conclusions: Galectin-3 immunostaining represents a valid pre-operative adjunct to pick up malignant cells in those cases where a very poor number of epithelial cells may lead to a cytological misdiagnosis. Therefore, we suggest that in poorly cellular FNA biopsies of simple or complex thyroid cysts, galectin-3 expression by epithelial cells is consistent with a cystic carcinoma and supports surgical treatment indication.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Carcinoma, Papillary / chemistry*
  • Carcinoma, Papillary / pathology*
  • Epithelial Cells / chemistry
  • Epithelial Cells / pathology
  • Female
  • Galectin 3 / analysis*
  • Humans
  • Immunoenzyme Techniques
  • Keratins / analysis
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Retrospective Studies
  • Sensitivity and Specificity
  • Thyroid Neoplasms / chemistry*
  • Thyroid Neoplasms / pathology*

Substances

  • Galectin 3
  • Keratins