Hemocytometer leukocyte adherence inhibition technique

The hemocytometer leukocyte adherence inhibition technique was employed in a criss-cross experimental design with two cancer patients (melanoma and colon carcinoma) and the corresponding tumor extracts. These extracts had been repeatedly tested for specific reactivity and lyophilized before transport to the workshop. The patients' leukocytes were mixed singly with each extract in the presence of normal serum, and the adherences of the cells were determined in hemocytometer chambers. Actual cell counts (total cells before washing and adherent cells after washing) are given in detail for the first time. Blood samples and reaction mixtures were coded by an independent observer. Determination of mean % adherence (+/- S.E.) showed that the melanoma patient's leukocytes (original adherence 70.8 +/- 2.8) reached with the melanoma extract (40.7 +/- 2.9; p less than 0.001) but not significantly with the colon carcinoma extract (61.5 +/- 4.1; p greater than 0.05). Similarly, the colon carcinoma patient's leukocytes (original adherence 68.6 +/- 2.7) reacted with the colon carcinoma extract (43.2 +/- 2.3; p less than 0.001) but adherence was not inhibited by the melanoma extract (76.9 +/- 2.6). The cancer patients were thus correctly identified with regard to tumor type in a simple blind trial.