Estrogen Receptor Immunocytochemistry for Preoperative Determination of Estrogen Receptor Status on Fine-Needle Aspirates of Breast Cancer

Angelika Reiner, Georg Reiner, Jürgen Spona, Bela Teleky, Roland Kolb, Johann H. Holzner
1987 American Journal of Clinical Pathology  
Fine-needle aspirates (FN As) of 84 primary breast carcinomas were analyzed immunocytochemically for estrogen receptor (ER) using (ER-ICA) monoclonal antireceptor antibodies. ER-ICA in FN As was concordant to ER-ICA in histologic biopsies in 87% (P < 0.0001). In most of the carcinomas, biochemically determined ER status also correlated to ER-ICA. There was no false positive ER-ICA in FNAs compared with ER-ICA in histologic biopsies. In 11 FNAs, ER-ICA was negative, whereas it showed positivity
more » ... showed positivity in histologic specimens. The most frequent contributing factors to false negative ER-ICAs of FNAs were ER-ICA-low results in histologic biopsies, a prominent stroma component in these tumors, and low cellularity of FNAs. The biochemical ER values in these cases never exceeded 90 fmol/mg protein. In a minority of cases, false negative results were inexplicable. (Key words: Estrogen receptor immunocytochemistry; Monoclonal antibodies; Breast cancer; Fine-needle aspiration) Am J Clin Pathol 1987; 88: 399-404 ESTROGEN RECEPTOR (ER) assays are generally accepted for selection of patients with breast cancer for endocrine therapy. For conventional biochemical ER assays, surgical biopsies are required to obtain sufficient tissue specimens. However, in many patients with recurrent or inoperable carcinoma, surgical specimens for ER determinations are not readily available. With recently developed monoclonal antibodies to ER, the ER protein itself was demonstrated immunocytochemically at the cellular level. 7 Significant associations of immunoperoxidase staining in histologic specimens using this monoclonal antibody to ER and concentrations of biochemically determined cytosolic ER were reported. 8 1 2 1 3 1 5 With this ER immunocytochemical assay (ER-ICA), ER determination in very small tissue samples and even fine-needle aspirates (FNAs) is possible now. Therefore, for many patients where the ER status remained unknown in the past, ER determination could be possible now in an atraumatic procedure. This study was undertaken to determine the reliability of the ER-ICA in FNAs of breast carcinomas. The results are compared with ER-ICAs in histologic biopsies and with biochemically determined ER status. Moreover, the possible reasons for cases showing discrepancies were analyzed. Materials and Methods FNAs were taken in 124 consecutive cases of primary breast carcinoma in situ before surgery. For aspiration biopsy, a 20-mL syringe was mounted on a Franzen® pistol and a needle of 0.7-0.8 mm diameter was routinely used. The needle was introduced into the lesion, the pistol retracted, and the needle moved back and forth into different areas of the tumor. 18 In 84 FNAs sufficient cell material was available for a malignant cytologic diagnosis. Cytologic smears showing hypocellularity with less than 20 cells on the slide were excluded from the study. FNAs were assayed for ER immunocytochemically using the ER-ICA Monoclonal Kit® (Abbott Laboratories, Diagnostic Division, North Chicago, IL). According to the ER-ICA protocol, glass slides pretreated with tissue adhesive were used for FNA and frozen sections. Of each case, one smear was fixed in Zamboni's fixative at room temperature, pH 7.3, for 10 minutes, according to the method of King and associates. 8 Zamboni's fixative was used because it is not necessary to prepare it freshly every day, as is suggested for formaldehyde-phosphate-buffered saline (PBS) by ER-ICA protocol. Therefore, it is possible to provide the clinicians with the fixative in advance. After that, smears were placed in cold absolute methanol at -20 °C for 4 minutes and then cold acetone at -20 °C for 1 minute. Thereafter, samples were collected at -20 °C in storage medium and immunocytochemistry performed strictly according to the ER-ICA protocol. Briefly, specimens were incubated in the primary monoclonal antiestrogen receptor antibody, followed by a bridging secondary antirat immunoglobulin, which was followed by peroxidase antiperoxidase complex. Staining reaction product was developed by diaminobenzidine-tetrahydrochloride. Counterstaining was performed with Harris hematoxylin. The second smear was air dried and stained by the May-Grunwald-Giemsa method. On this 399
doi:10.1093/ajcp/88.4.399 pmid:3661495 fatcat:kksc3mphnzh2dioindc6uiorpa