Immunohistochemical detection of lymph node metastases in node-negative breast cancer patients

Background: Axillary lymph node metastases in breast cancer patients are on e of the most important prognostic factors. Many previous studies have show n that in the detection of occult micrometastses immunohistochemical method s are superior when compared to routine hematoxylin-eosin staining. The aim of the stud was to document the rate of missed occult micrometastases on r outine hematoxylin-eosin staining in our department, in a retrospective stu dy. patients and Methods: One hundred and one tumors of patients with breas t cancer were included in this study. Immunohistochemical staining was perf ormed using Pan-Cytokeratin AE1/AE3 antibody. The number of nodes examined ws 1301 (mean pr patient: 12,9; range; one to 26). Results: Of the 101 tumo rs studied, eleven had occult lymph node metastases detected by immunohisto chemical methods. After repeated review by two independent pathologists, in two out of eleven patients lymph node metastases were confirmed even on he matoxylin-eosin staining. In nine out of eleven patients hematoxylin-eosin staining was not sufficient to detect occult micrometastases. Conclusion: I mmunohistochemical methods enhance the detection rate of occult micrometast ases in axillary lymph nodes of breast cancer patients and are recommended for routine diagnostic use in patients who have been diagnosed node-negativ e on routine hematoxylin-eosin staining.