F cells in gynaecologic malignancy.

Red cells containing Hb F (F cells) were detected by immunofluorescence using a specific antiserum. In normal persons, the number of F cells was 2.5 +/- 1.1%. A significantly increased number of F cells was found in 65% of patients with cancer of the ovary, 69% of patients with cancer of the endometrium and in 22% of patients with cancer of the cervix. Highest values were obtained in cancer of the ovary and endometrium. There was no correlation between the number of F cells and stage of disease or degree of differentiation. It is postulated that in patients with malignant disease a humoral factor is produced which interferes with normal erythropoiesis resulting in a process of dedifferentiation.