In our series, bone marrow positivity did not correlate with prognostic parameters or prognosis. Of interest is the relative excess of positivity when the bone marrow was obtained during surgery.

The presence of epithelial cells in bone marrow may be a prognostic factor in breast cancer, and so we evaluated their evolution in treated and untreated patients. A first bone marrow aspirate was obtained from 125 stage I/II breast cancer patients at diagnosis and repeated every 6-8 months; the samples were processed for leukocyte separation, used to prepare cytospin slides, stained with a pool of monoclonal antibodies (MoAb) recognising epithelial antigens, and immunocytochemically processed. The median follow-up was 48 months (range 15-82); 23 patients relapsed, and 14 died. MoAb positive cells were observed in 31.2% of first, 24.3% of second, and 27.8% of third aspirates. In 68/100 pairs of successive aspirates, bone marrow status remained unchanged; in 20 it became negative, and in 12 positive (not statistically significant even after adjusting for adjuvant therapy). An analysis based on Mantel and Byar's approach to time-dependent covariates using all 225 aspirates found no statistically significant prognostic difference between the patients with negative and positive bone marrow. Bone marrow status changed over time in about 1/3 of the patients; adjuvant therapy did not affect the probability of its becoming negative or positive. No significant association was found between bone marrow evolution and relapse or death, but the relatively high probability of a change in status over time cannot exclude the possibility that a positive aspirate during the course of breast cancer may be a negative prognostic factor.

The independent prognostic significance of isolated tumour cells in bone marrow is still a matter of debate. This study evaluated the possible association of bone marrow micrometastases with tumour progression and prognosis in patients affected by gastric cancer. Bone marrow aspirates from both iliac crests were obtained from 114 consecutive patients operated on for gastric cancer. The specimens were stained with monoclonal antibody CAM 5.2 which reacts predominantly with cytokeratin filaments 8 and 19. Among 114 cases analysed, 33 cases (29%) had cytokeratine-positive cells in the bone marrow. There was no significant relationship between the presence of bone marrow micrometastases and site, depth of tumour invasion, lymph node metastases, presence of metastases. Patients with cytokeratine-positive cells had a trend towards a diffuse type histology (P=0.06). Among the 88 curatively resected patients, median survivals were 40 months and 36 months for cytokeratine-negative and cytokeratine-positive subsets respectively (P=0.9). Recurrence of the disease was observed in 39 cases (44.3%); 11 of 24 (45.8%) in the cytokeratine-positive subset and 28 of 64 (43.7%) in the cytokeratine-negative subset. In conclusion in our experience the presence of cytokeratine-positive cells in the bone marrow of curatively resected gastric cancer patients did not affect outcome and its independent prognostic significance remains to be proven before its official acceptance in the TNM classification.

The independent prognostic significance of isolated tumour cells in bone marrow is still a matter of debate. This study evaluated the possible association of bone marrow micrometastases with tumour progression and prognosis in patients affected by gastric cancer. Bone marrow aspirates from both iliac crests were obtained from 114 consecutive patients operated on for gastric cancer. The specimens were stained with monoclonal antibody CAM 5.2 which reacts predominantly with cytokeratin filaments 8 and 19. Among 114 cases analysed, 33 cases (29%) had cytokeratine-positive cells in the bone marrow. There was no significant relationship between the presence of bone marrow micrometastases and site, depth of tumour invasion, lymph node metastases, presence of metastases. Patients with cytokeratine-positive cells had a trend towards a diffuse type histology (P=0.06). Among the 88 curatively resected patients, median survivals were 40 months and 36 months for cytokeratine-negative and cytokeratine-positive subsets respectively (P=0.9). Recurrence of the disease was observed in 39 cases (44.3%); 11 of 24 (45.8%) in the cytokeratine-positive subset and 28 of 64 (43.7%) in the cytokeratine-negative subset. In conclusion in our experience the presence of cytokeratine-positive cells in the bone marrow of curatively resected gastric cancer patients did not affect outcome and its independent prognostic significance remains to be proven before its official acceptance in the TNM classification.