We observed a small and non-significant increase in the percentage of Gr-1+/CD11b+cells in tumor-bearing mice compared to the controls (2.24±0.75% vs. 1.78±0.41% in spleen and 37.7±8.6% vs. 35.0±0.67% in bone marrow) following 1 week of myeloma implantation. This evidence concerns the gene ITGAM and plasma cell myeloma.