Deficiency in maturation process of macrophages in human cancer.

Peripheral blood mononuclear cells were cultured from normal individuals and patients with cancer. The analysis of these results indicated a lower number of macrophage precursors (monocytes) in patients with cancer as compared to the number in normal individuals. The macrophage yield was 1.9 +/- 1.1 X 10(4)/ml of blood in patients with cancer versus 7.2 +/- 2.0 X 10(4)/ml of blood in normal individuals. This low yield of macrophages in patients with cancer was not associated with serum factors. Furthermore, a study of the adherent cell population suggests in intrinsic defect in the maturation process in vitro in patients with cancer.