Serum immunosuppressive acidic protein in renal cell carcinoma.

Serum immunosuppressive acidic protein (IAP) was determined in 45 patients with renal cell carcinoma (20 preoperative and 25 postoperative) and 12 healthy adults. The mean values of serum IAP in patients with renal cell carcinoma of low stage (566.3 +/- 197.7 micrograms/ml) and high stage (936.9 +/- 208.8 micrograms/ml) were statistically higher than those of controls (368.8 +/- 84.5 micrograms/ml). Positive rate of IAP levels was found in 58.3% and 100% of patients with low stage and high stage, respectively. The mean value of serum IAP was 756.4 +/- 361.0 micrograms/ml in patients with metastases, while patients without metastases had a value of 434.7 +/- 170.9 micrograms/ml. There was a statistically significant difference between the two populations. These results suggest that IAP levels appear to provide a useful diagnostic and follow-up marker in renal cell carcinoma patients.