Evaluation of a radioimmunoassay for alpha 1-acid glycoprotein to monitor therapy of cancer patients.

A new radioimmunoassay for alpha 1-acid glycoprotein (AGP) for monitoring the therapy of cancer patients was evaluated. Plasma levels of this glycoprotein were measured in 49 normal healthy volunteers, 71 patients with illnesses other than cancer, 190 patients with solid tumors, and 58 patients with hematologic neoplasms. Plasma levels of AGP were elevated in 89% of the solid tumor patients and 87% of the patients with hematologic neoplasms who had newly diagnosed, locally recurrent, or metastatic cancer. Only 18% of patients with illnesses other than cancer and normal renal function had elevations of plasma AGP. Serial measurements of AGP may be useful for monitoring therapy in several tumor types, including small-cell lung cancer, colon cancer, lymphoma, and non-small-cell lung cancer.