title: Expression of bcl-2 by breast cancer: a possible diagnostic application.
abstract: Expression of bcl-2 is most commonly associated with the t(14;18) translocation present in most folicular lymphomas (1). More recently, bcl-2 oncoprotein has been identified in normal tissues and in nonhematologic malignancies. In this study, we investigate the use of bcl-2 as a marker to distinguish metastatic breast carcinoma from primary lung and gastric cancers, and we evaluate the role of bcl-2 as an independent prognostic factor in breast carcinoma and its relationship to other breast cancer markers. bcl-2 immunostains were done on 371 adenocarcinomas of the breast, lung, and stomach. Additionally, 231 samples of metastases from patients with breast or gastric cancer were evaluated for bcl-2 expression. All breast cancer tissue samples had immunohistochemical data on expression of estrogen and progesterone receptors, p53, neu/cerb2, and MIB-1. A large proportion (79.3%) of invasive breast carcinomas expressed bcl-2, whereas only 5.6% and 8.3% of pulmonary and gastric carcinomas did. Moreover, staining was moderate to intense in 70.2% of the breast cancers, compared with only one specimen of lung carcinoma (1.9%) and gastric carcinoma (0.9%) that showed moderate staining. There was agreement of bcl-2 expression between primary and metastatic sites in all specimens except one. Expression of bcl-2 in breast adenocarcinomas was significantly associated with hormone receptor positivity and low histologic grade. Nonetheless, 20.6% of bcl-2-positive specimens were estrogen receptor negative and 24.2% of bcl-2-positive specimens were progesterone receptor negative. Neither the presence nor the absence of bcl-2 expression significantly predicted disease-free survival or overall survival in patients with breast cancer. We conclude that adenocarcinomas with intense bcl-2 staining are more likely to be of breast than of pulmonary or gastric origin. We recommend the addition of bcl-2 to a panel of antibodies (estrogen receptor, GCDFP-15, and S100) that might contribute to the identification of a larger proportion of metastatic breast carcinomas, because almost one-half of the estrogen-receptor negative cancers were bcl-2 positive.
authors.affiliation: Department of Pathology, City of Hope National Medical Center, Duarte, CA 91010, USA.
authors.forename: R
authors.initials: R
authors.lastname: Alsabeh
authors.forename: C S
authors.initials: CS
authors.lastname: Wilson
authors.forename: C W
authors.initials: CW
authors.lastname: Ahn
authors.forename: M A
authors.initials: MA
authors.lastname: Vasef
authors.forename: H
authors.initials: H
authors.lastname: Battifora
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000235:genetics* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000473:pathology; D019254:Genes, bcl-2; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000473:pathology; D008875:Middle Aged; D011379:Prognosis; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor