Significance of lipid-associated sialic acid and CA 19-9 as tumor markers for renal cell carcinoma.

Numerous neoplasms, including colonic, lung, stomach, and prostate, have been found to have increased concentrations of lipid-associated sialic acid (LASA). CA 19-9 is a carbohydrate antigen found on the membrane surface of pancreatic, gastric, and colonic cancers. A prospective study involving 25 patients (15 males, 10 females) with renal cell carcinoma (RCC) was undertaken to examine the clinical value of these two markers. Patients' ages ranged from twenty-five to seventy-seven years (mean 56 years). The group consisted of 9 Stage I, 1 Stage II, 5 Stage III, and 10 Stage IV patients. Twenty three of the 25 had known disease present when tested. Eleven patients with no known tumor were used as an age-matched control group. Sixteen of the 23 patients with known disease (70%) had elevated LASA values. Nine of the 11 control patients (82%) had normal LASA values. Three of 7 patients with values obtained pre- and post-nephrectomy showed levels returned to normal after nephrectomy; 3 had persistent LASA elevation and were found to have either metastatic or recurrent disease, and 1 had a persistent elevation of his LASA value without known metastatic or recurrent disease. When the 23 patients with known disease were compared according to stage, 62 percent of Stages I and II, 80 percent of Stage III, and 70 percent of Stage IV had elevated LASA values. There was no statistically significant difference between LASA values and tumor stage. CA 19-9 values obtained in 15 of 25 patients with RCC were within normal range.