Evaluation of immunosuppressive acid protein in genitourinary malignant diseases

: Clinical significance of serum immunosuppressive acid protein (IAP) was evaluated on the basis of experience on 55 patients with genitourinary malignant disease and 49 control patients. Although the measurement of serum level of IAP is not good enough to diagnose early stage of cancer, patients with 800 micrograms/ml or more of serum IAP can be suspected to have malignant diseases. With the exception of prostatic cancer, both mean serum level and positive rate of IAP were higher in patients with high stage of disease than in those with low stage. Furthermore, on an individual basis, serum level of IAP was elevated with the progress of malignant tumor and was reduced with effective treatment. Thus, serum IAP is considered as a valuable nonspecific tumor marker in monitoring clinical course of genitourinary malignant diseases except for cancer of the prostate. In patients with advanced prostatic cancer, no definite correlation was seen between serum IAP and stage of disease, histopathological finding or serum prostatic acid phosphatase.