Immunohistochemical study of estrogen receptors and the responsiveness to estrogen in papillary thyroid carcinoma

Abstract

Background. Epidemiologic data suggested that the differentiated thyroid carcinoma was affected by sex hormones, especially estrogen. Methods. The authors have immunohistochemically studied estrogen receptors (ER) in papillary thyroid carcinoma in women. Two anti‐ER monoclonal antibodies, D5 and H222, were used. The authors then investigated the responsiveness to estrogen of thyroid neoplasms using primary culture of surgically resected thyroid tissues. The proliferative activity of cultured cells was measured by the bromodeoxyuridine (BrdU) labeling index (LI). Results. Twenty‐six percent of the specimens (18/70) showed positive staining with D5, but only 5.6% of the specimens (2/36) showed positive staining with H222. The BrdU LI of ER‐positive papillary thyroid carcinoma increased with the addition of estradiol. Conclusions. These findings indicate that estrogen may affect the proliferation of ER‐positive papillary thyroid carcinoma. Copyright © 1993 American Cancer Society