Estrogen receptors in human thyroid gland. An immunohistochemical study.

Objective: Thyroid diseases affect women approximately 3 times more frequently than men. It has been suggested that the female sex steroids stimulate thyroid growth such as in the breast. Seventeen beta-estradiol, the major estrogen in the body acts via estrogen receptors (ER) present in the nucleus of the cell. The aim of the study is to determine the ER status in the thyroid gland tissues.

Methods: Our study was based on immunohistochemical staining for ER. Fifty previously diagnosed cases of various thyroid lesions were selected from the Surgical Pathology Records of Pathology Department, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Center, Karachi, Pakistan between March and August 2000. The staining was performed on formalin-fixed paraffin embedded tissues using monoclonal anti-ER antibody (clone 1D5). Out of 50 cases, 8 were nodular goiter, 9 cases of adenoma, 19 papillary carcinoma, 10 follicular and 4 cases were of medullary carcinoma. Surrounding normal tissue was available in 25 (50%) cases, 4 non-neoplastic and 21 neoplastic lesions. Out of 50 cases, 10 (20%) were males and 40 (80%) were females, the youngest patient was a 14-year-old female and the eldest patient was a 56-year-old male.

Results: Despite the availability of normal thyroid tissue and a wide range of lesions, none of our cases showed positive staining.

Conclusion: In contrary to many earlier reports by immunohistochemical method using monoclonal antibody (clone 1D5) on formalin-fixed paraffin-embedded thyroid tissues, the ER are not detectable. The effect of estrogen on thyroid gland may be indirect one.