Neopterin is an independent prognostic variable in females with breast cancer

Background: Neopterin, produced by human monocytes/macrophages upon stimula tion by interferon-gamma, is a sensitive marker for monitoring Th1-cell imm une response in humans. In malignant diseases, the frequency of increases i n neopterin in the serum and urine of patients depends on tumor stage and t ype. Methods: In a retrospective study comprising 129 females with breast cancer , urinary neopterin/creatinine ratios were measured at the time of diagnosi s. Tumor characteristics were determined concomitantly. Results: Urinary neopterin was increased in 18% of the patients. It did not correlate with tumor size or lymph node status, but it was influenced by t he presence of distant metastases (P <0.05) and by tumor differentiation (P = 0.01). When product-limit estimates were calculated after follow-up for up to 13 years (median follow-up, 56 months), the presence of distant metas tases (P <0.001), neopterin (P <0.001), tumor size (P=0.001), and lymph nod e status (P <0.01) were Significant: predictors of survival. By multivariat e analysis, a combination of the variables presence of distant metastases ( P <0.001), neopterin (P <0.01), and lymph node status (P < 0.05) was found to jointly predict survival. In lymph node-negative patients without distan t metastases, the relative risk of death associated with increased neopteri n concentrations was 2.5 compared with patients with neopterin concentratio ns within the reference interval. Conclusion: Urinary neopterin provides additional prognostic information in patients with breast cancer. (C) 1999 American Association for Clinical Ch emistry.