Studies of lymphocyte adenosine deaminase activity in patients with renal and transitional cell carcinoma.

Adenosine deaminase (ADA) is a critical enzyme in purine metabolism and lymphocyte ADA activity is specifically related to immunocompetence in man. Since immunologic factors are relevant in patients with renal and transitional cell carcinoma, we studied lymphocyte ADA activity in these patients. In renal adenocarcinoma patients lymphocyte ADA activity was reduced. Such reductions were most marked in low-as compared to high-stage lesions. Nephrectomy resulted in a rise and disease progression in a decline in ADA activity. In contrast, bladder, carcinoma patients showed elevated lymphocyte ADA activity most marked in high-stage lesions. Disease progression was associated with a rise and tumor resection with a decline in lymphocyte ADA activity. Discordance in patterns of lymphocyte ADA activity when patients with renal and transitional cell carcinoma are compared suggests unique host-tumor interactions at the enzyme level. Studies of ADA may offer insight into molecular aspects of immune mechanisms.