Urinary neopterin levels in patients with genitourinary tract malignancies

Abstract

Neopterin is released from macrophages upon stimulation with gamma-interferon, secreted by activated T cell. Therefore it has been recognized as a useful indicator of the activation of the T cell-macrophage system. Increased neopterin levels are observed in patients with acute graft rejections, viral infections, auto-immune diseases and several malignancies. Urinary neopterin concentrations were determined in patients with genitourinary tract malignancies to evaluate the usefulness of neopterin as a tumor marker. Urinary neopterin concentrations were determined by high-performance liquid chromatography in 90 patients with genitourinary tract malignancies and 28 patients with benign urological tumors and 34 healthy subjects. Increased urinary neopterin levels were observed in 52% of the patients with genitourinary tract malignancies and 7% with benign urological tumors. The positivity rate in patients with renal cell carcinoma (RCC), renal pelvic and ureteral tumor, bladder tumor (BT), prostatic carcinoma (PC) and testicular tumor was 68%, 80%, 47% and 30%, respectively. The difference in the urinary neopterin levels between low and high stages was highly significant (p < 0.0005) in patients with RCC (stage I-II vs. stage III-IV) and BT (T1S-1 VS. T2-4). The urinary neopterin levels were also correlated with the tumor grade in patients with RCC and PC. Our study suggests that urinary neopterin levels may supplement laboratory examinations for patients with genitourinary tract malignancies, providing useful information in evaluating the tumor stage and follow-up of the disease.