Cell-mediated immunity in prostatic cancer and its diagnostic relevancy.

Cell-mediated immunity (CMI) in prostatic cancer patients to presumptively identified prostatic tumour-associated antigens (TAA) was further evaluated in this study by tube leukocyte adherence inhibition in 504 patients with and without prostatic cancer. Peripheral blood leukocytes from 210 of 312 (67%) prostatic cancer patients possessed significant reactivity to extracts of malignant prostate. However, significant reactivity to malignant prostate was also observed in 89 of 192 (46%) controls comprised of patients with other than carcinoma of the prostate [including 91 patients with benign prostatic hypertrophy of which 46 (51%) possessed significant reactivity to malignant prostate] and healthy adults. With the exception of a significant difference in the reactivity between stage A vs stage C patients, there was no significant correlation between the level of reactivity to malignant prostate and the stage of disease. Had CMI to presumptively identified prostatic TAA been employed as an adjunctive diagnostic criterion to detect prostatic cancer, 191 (38%) of the 504 patients in this study would have been incorrectly diagnosed. The results of this study emphasize the critical need in attempting to delineate tumour-directed immunity from possible concomitant sensitization to tissue- and species-specific antigens for the identification, isolation and physicochemical characterization of what previously have been referred to as presumptively or putatively identified prostatic TAA.