[Detection of micrometastases in excised regional lymph nodes in cancer of the breast. Systematic use of KL1 anticytokeratin monoclonal antibodies in a prospective series of 120 T2 N- patients].

A series of 120 patients (T2, No, N1a according to UICC classification) with mammary cancer treated by mastectomy and regional lymph node dissection, classified T2N-after Hemalun-Phloxine Safran (HPS) standard sections, have a positive reaction with immunohistochemical staining (IHM) using monoclonal antibodies (anti KL1) so that IHM improve the detection of lymph node metastases. 13 patients out of 120 presumed N-after HPS technic became positive with IHM staining. We examined 2108 lymph nodes and noticed 19 N+, the size of which was less than 2 millimeters. Microscopically, three main aspects are follows. Micrometastases made of clusters of malignant cells; micrometastases with single cells in file, and a composite aspect from both previous ones. Metastatic cells detected by anti KL1 have an excellent contrast due to clear nucleus surrounded by a large rim of dark cytoplasm. Although T2N-has a better prognosis than T2N+, 10 to 20% of patients relapsed within ten years after surgical treatment. It is important to determine whether the detection of occult micrometastases permits to predict recurrence. Is it a relevant correlation or not? if such a connection does'not exist, micrometastasis detection became irrelevant; on the contrary, if it exists, the therapists can launch on adequate adjuvant treatment - useful only - for patients with high risk of relapse.