Prognostic relevance of urinary neopterin in non-Hodgkin's lymphomas

Neopterin excretion levels were assessed in 66 consecutive patients affected by non-Hodgkin's lymphomas (NHL). The logarithm of the mean value of the whole series was 2.71 (log [mumol neopterin/mol creatinine]), significantly higher (P less than 0.001) than the control value (2.12). Fifty-six of 66 patients had a raised excretion of neopterin in amounts statistically related to the stage of disease. The mean value (2.51) of patients in Stages I-II was lower than the mean value (2.86) of patients in Stage III-IV (P less than 0.001). The 2-year probability of survival was 64% for patients in Stages I-II and 34% for patients in Stages III-IV. However, patients with lower neopterin excretion (less than 2.65) fared better than patients with higher neopterin excretion, regardless of the stage. Longitudinal analysis showed a trend toward a correlation between response to therapy and neopterin excretion. In NHL, the raised neopterin excretion appears to be a consequence of activation of the host immune system rather than a product of the malignant cells. But this excessive activation of the monocytes-macrophages, as reflected by urinary neopterin levels, is not accompanied by a better outcome. In conclusion, although neopterin cannot be considered a typical tumor marker, nevertheless it is an useful prognostic marker in NHL.