1. ¹Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
2. ²Department of Pathology, The University of Chicago, Chicago, IL, USA

Correspondence: Dr AG Montag, MD, Department of Pathology, MC6101, University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA. E-mail: amontag@mcis.bsd.uchicago.edu

Received 22 January 2004; Revised 6 April 2004; Accepted 6 April 2004; Published online 2 July 2004.

Abstract

The importance of estrogen in vascular neoplasia is suggested by a predilection for women and a tendency for rapid growth during pregnancy. Although early experiments using radioligand assays demonstrated estrogen receptor (ER) expression, these findings were not confirmed by subsequent immunohistochemical studies which were performed with antibodies raised against ER. A newly discovered estrogen receptor subtype, ER, has not been previously characterized in vascular lesions. In order to verify the expression of estrogen receptors in vascular neoplasms as well as to clarify the inconsistency between radioligand and early immunohistochemical studies, we examined a series of 53 benign and malignant vascular neoplasms for ER expression. All of the subtypes of vascular neoplasia examined had nuclear expression of ER. The majority of cases (94%) displayed 2+ to 3+ staining. The discrepancy between radioligand studies and previous immunohistochemical studies is attributable to the use of antibodies raised against ER, which is not expressed in vascular lesions, and not ER, which is broadly expressed in both benign and malignant vascular neoplasms. Although ER may be of limited diagnostic use in vascular neoplasia due to its broad expression, the potential exists for a therapeutic approach using ER agonists.