Controversy still exists over in the prognostic significance of microscopic tumor cell dissemination in patients with cancer. This study evaluated the prognostic implication of isolated tumor cells in the bone marrow of patients with gastric cancer.

Four hundred nineteen (419) patients who underwent surgery for gastric cancer between June 1998 and July 2000 were enrolled in the study. Bone marrow aspirate was obtained from the iliac crest before removal of the primary tumor. Mononuclear cells were isolated and stained with AE-1/AE-3 PAN-CYTOKERATIN.

Cytokeratin-positive cells were found in the bone marrow of 219 patients (52.3%). The incidence varied significantly with the depth of invasion (P=0.021) and the stage (P=0.026). The five-year survival rate of patients with cytokeratin-positive cells was 74.1% and that of patients without cytokeratin-positive cells was 81.1% (P=0.2481). There were no significant differences in the recurrence rate and the site of recurrence according to whether or not cytokeratin-positive cells were present in the bone marrow.

The presence of cytokeratin-positive cells in the bone marrow of patients with gastric cancer did not predict outcome and recurrence. Therefore, it cannot be used as a prognostic factor.