BONE-MARROW MICROMETASTASES IN 109 BREAST-CANCER PATIENTS - CORRELATIONS WITH CLINICAL AND PATHOLOGICAL FEATURES AND PROGNOSIS

Background: The presence in bone marrow of cells which react with mono clonal antibodies against tumor-associated antigens has been proposed over the last few years as a new prognostic factor in breast cancer pa tients. Patients and methods: Bone marrow aspirates were obtained from 109 stage I and II breast cancer patients during or 2-4 weeks after p rimary surgery. The samples were processed for leukocyte separation on a Ficoll-Hypaque gradient and then used to prepare cytospin slides fo r immunocytochemical analysis. The slides were stained with a pool of monoclonal antibodies (MoAbs) which recognize tumor associated antigen s, using the alkaline phosphatase anti-alkaline phosphatase method. Th e median follow-up was 36 months (range 15-62); 22 patients relapsed a nd 7 died. Results: Thirty-four of the 109 patients (31.1%) had MoAb p ositive bone marrow cells. The bone marrow was positive in 28/74 (37.9 %) patients who had the aspirate taken during surgery and in 6/35 (17. 1%) who had it taken after surgery (p = 0.055). No association was fou nd between bone marrow positivity and tumour size, nodal status, menop ausal status, estrogen receptor positivity or the proliferative index. No association was found between bone marrow and prognosis: the log-r ank test was 0.291 (p > 0.5) for OS and 0.023 for DFS; the hazard rati o (positive vs negative) was 1.51 for OS (95% CI: 0.33-6.86) and 0.93 for DFS (95% CI: 0.35-2.45). Conclusions: In our series, bone marrow p ositivity did not correlate with prognostic parameters or prognosis. O f interest is the relative excess of positivity when the bone marrow w as obtained during surgery.