PROGNOSTIC VALUE OF BONE-MARROW BIOPSY IN OPERABLE BREAST-CANCER PATIENTS AT THE TIME OF INITIAL DIAGNOSIS - RESULTS OF A 20-YEAR MEDIAN FOLLOW-UP

From May 1975 until May 1980,128 operable breast cancer patients, clin ical stage I-II, had a core bone marrow biopsy (BMB) from the posterio r iliac crest as a part of the routine diagnostic work-up at the time of initial diagnosis. The mean age of the patients was 56 years, range 26-93. In a previous study on this material, 10 patients (7.8 per cen t) were positive for tumor cells and 118 negative by conventional hist opathology of BMB [1]. In 1996 we reexamined all BMB separately at two laboratories, using monoclonal antibodies against cytokeratins AE1-AE 3, KL1, CAM 5-2 (DOP), and DC10, BA17 (MCI). The number of extrinsic c ells in the bone marrow was graded positive for micrometastases when g reater than or equal to 5 cells or suspicious when 1-4 cells per simil ar to 2 X 10(6) bone marrow cells were found, using high power field m agnification. Micrometastases were detected in 17 patients (13.3 per c ent) and another 8 patients were classified as suspicious. The presenc e of micrometastases was correlated to the axillary lymph node stage a nd primary tumor location. Median follow-up was 20 years. All 17 micro metastatic patients relapsed and died within 6 years of disease progre ssion with evident osseous metastases. There was one disease-free surv ivor of the 8 patients with suspicious BMB after 17 years of follow-up . The median overall survival was significantly shorter in tumor-cell positive patients, being 1.9 years compared to 11.7 years in the BMB n egative and BMB suspicious groups (p < 0.0001). Immunohistochemical an alysis of core BMB taken postoperatively may be useful in predicting t he prognosis in patients with breast cancer clinical stage I-II.