Immunohistochemical Expression of Prostate-Specific Membrane Antigen in Malignant Thyroid Lesions

Abstract

Introduction:

Prostate-specific membrane antigen (PSMA) is a zinc-dependent peptidase overexpressed in prostate cancers, making them amenable to imaging and targeted radionuclide therapy. However, its expression is not only restricted to prostate cancer but has also been demonstrated in tumor neovasculature (vascular endothelium), gliomas, and lung cancers.

Objectives:

1. To study the immunohistochemical expression of PSMA in malignant thyroid lesions.


2. Correlation of expression of PSMA among different grades of malignant thyroid tumor.

Methodology:

The present Hospital-based cross-sectional study was carried out in the histopathology section, pathology department of the tertiary center.  Vijayapura during the period from 1^st September 2022 – 31^st December 2023 involved 30 cases who underwent excision of the thyroid gland.

Results

The most common malignant thyroid lesion is papillary carcinoma followed by follicular, medullary, and anaplastic carcinoma. According to gender-wise distribution, most of the malignant thyroid lesions are more common in females when compared to males. The expression of PSMA is seen in the lining endothelial cells of the blood vessels within the tumor. The expression is considered positive when the endothelial cell shows brown discoloration, the expression is considered negative when the endothelial cell shows no staining. PSMA is seen in 100% of cases of papillary carcinoma, 75% of follicular carcinoma, 50% of cases of medullary carcinoma, and negative expression in anaplastic carcinoma.

Conclusion:

These results help to explore novel biomarkers such as PSMA in thyroid cancer diagnosis and management.