Lipid bound sialic acid in cancer patients.

Serum lipid-bound sialic acid (LSA) was measured with a recently described procedure in 108 healthy subjects and in 138 patients with a variety of solid tumors and hematologic malignancies. At the time of serum sampling, 128 patients had active disease and 10 patients had no evidence of disease. LSA was elevated in 104 of 128 (81.2%) patients with active disease, while carcinoembryonic antigen, analyzed in 74, was elevated only in 21 (28.4%) (P less than 0.05). Sensitivity of the serum LSA test ranged from 66% for breast and gastrointestinal cancer to 92% for lung cancer. In patients with lung cancer, ovarian cancer or Hodgkin's disease, LSA was correlated with the extent of disease and it also proved to be useful in following the course of disease. Our preliminary data indicate that this test can be used as a monitor of tumor burden.