Predictive value of estrogen receptors evaluated by immunocytochemical analysis in breast cancer patients

Abstract

BACKGROUND: The determination of estrogen receptor (ER)status is valuable in selecting the appropriate therapy and predicting prognosis for patients with invasive breast carcinoma. OBJECTIVE: The aim of our study was to assess the predictive value of ER status evaluated preoperatively by immunocytochemical analysis and compared with recurrence rate, clinical and histopathological features in 52 patients with breast carcinoma. MATERIALS AND METHODS: Fifty-two aspirates obtained by fine-needle-aspiration biopsy (FNAB) were prepared as cytospin samples for ER-immunocytochemical analysis (ER-1CA). Cytospin slides were stained using a standard procedure with horseradish peroxidase-antiperoxidase (PAP) method, utilising monoclonal antibody to ER (H222SP, ER-ICA kit, Abbott Laboratories, USA). The assessment of staining was scored in a semiquantitative fashion incorporating the intensity and the distribution of stained cells and the values were designated as IS-CYTOSCORE. All the patients underwent radical mastectomy with axillar lymphadenectomy during the period from September 1990 to March 1992 and were staged according to the postoperative pTNM classification of UICC (1987) guidelines. During the follow-up period (range, 2-75 months, mean 32) recurrences were observed in 25 (48%) patients.ER status was correlated to recurrence rate, age of the patients, type of the breast carcinoma, tumor size, grade of histologic differentiation, desmoplastic reaction, elastosis, necrosis and calcifications. The comparison was made by cross-classification and statistical significance determined by χ2 and Fisher's exact test. RESULTS: ER status was positively detected in 28 (53.8%) patients. There is significant association between ER status and age of the patients (p = 0.02), the type of the breast carcinoma (p = 0.018), and the recurrence rate (p = 0.012). Eighteen out of 26 (70%) patients 50 years or older, were positively related to ER status. In 22 (42.3%) lobular carcinomas, ER status was positive in 16 (73%) patients, compared with 30 (57.7%) ductal carcinomas, with ER status positive for 12 (40%) patients, only. Recurrences were observed in 16 (64%) patients with ER- breast carcinomas and 9 (36%) patients with ER+ breast carcinomas. Less important histopathological features as elastosis and calcifications, demonstrated statistically significant positive relation with ER status (p = 0.004 and p = 0.005, respectively). No significant association was found between the ER status and other histopathological characteristics. CONCLUSION: Our results suggest that recurrences, age of the patients and the lobular type of breast carcinoma are positively correlated with ER status. These data are consistent with the results of other similar studies. On the other hand, the stage of the disease as well as the grade of histologic differentiation and lymph node involvement, demonstrated no significant association with ER status as expected. A small number of cases studied and the heterogeneous stages included, could explain some of the differences between our data and the results from other studies. Semiquantitative ER-1CA, as fast and simple method, is especially useful in determination of ER status in recurrent, metastatic and small-sized breast carcinomas. The great advantage of ER-ICA is in a possibility of ER status preoperative determination, and repeating the procedure, if necessary. Despite the good performances, some inherent difficulties must be noted: subjectivity in scoring and detection by antigenicity of ER. Therefore, ER status quantitative assessment by using Cell-Analysing-System (CAS) and concomitant quantitative measurements of progesterone receptor status, should be of additional benefit.