Comparison between NK cell activity and prostate cancer stage and grade in untreated patients: correlation with tumor markers and hormonal serotest data.

NK cell activity was measured in 24 patients with untreated prostate cancer (11 subjects with localized disease, D0, and 13 patients with stage D tumor) and 10 healthy controls. In these same subjects serum prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), testosterone, prolactin and cortisol concentrations were assessed. The data obtained were correlated with both tumor spread (localized vs disseminated disease) and grade (well-differentiated cancer, G1, vs moderately and poorly differentiated carcinoma, G2 and G3). In patients with stage D0 cancer mean NK activity (33.0 +/- 10.6) was virtually identical with the mean value recorded in healthy men (34.5 +/- 7.1), while in subjects with stage D1-D2 disease NK activity was significantly reduced (11.9 +/- 7.1). These findings correspond with our data on treated subjects, in whom NK activity level was found to correlate well with the presence of tumor cells in the circulation. In subjects free of malignant tumors but with a chronic disease (diabetes, arthritis, severe rheumatic disorders) mean NK activity was clearly reduced (5.7 +/- 1.5). The use of NK activity data as a probe for tumor metastases was found to be statistically as reliable as was the application of the PSA serotest (but not serum PAP concentrations). None of the measured hormonal parameters correlated well with tumor stage. Both testosterone and prolactin serum concentrations were found to be lower in the G2 and G3 cancer group than in well-differentiated (G1) tumors, in accordance with the published literature.(ABSTRACT TRUNCATED AT 250 WORDS)