Utility of tumor marker CA 72.4 in patients with chronic renal failure

The tumor marker CA 72.4 is composed of two monoclonal antibodies, B 72.3 and cc49, which detect the glycoprotein TAG 72 present in tumor cells. The levels of CA 72.4 may be modified depending on the route of excretion of the antigen TAG 72. The objective of this study was to evaluate the behavior of CA 72.4 in healthy subjects and to assess the influence of chronic renal failure (CRF) on the levels of this tumor marker. Random serum samples were collected in 181 individuals (148 healthy volunteers and 33 patients with CRF) and 214 determinations of CA 72.4 were performed. We also performed 66 determinations of plasma creatinine. In healthy subjects the cutoff value of CA 72.4 was established at 3 U/mL, with a sensitivity of 53% and a specificity of 85.8%. In the CRF patients we found no statistically significant differences when we compared the values of CA 72.4 predialysis and postdialysis (p = 0.197). However, a statistically significant difference was found in the plasma creatinine levels (p < 0.001). Chronic renal failure does not affect the result of CA 72.4 determinations; this tumor marker may therefore be useful in the monitoring of patients with cancer, independent of their renal function.