Urinary gonadotropin fragment measurements in patients with lung and esophageal disease.

Urinary gonadotropin fragment (UGF), a small glycoprotein and an intracellular processing product of human chorionic gonadotropin, has been demonstrated in trophoblast tissue and in nontrophoblastic cancers. Levels of UGF were assayed in 107 patients with malignant and benign pulmonary and esophageal lesions to determine if elevated levels were associated with the presence or progression of malignancy. There were 64 patients with primary bronchogenic carcinoma, 9 with metastatic pulmonary malignancies, 7 with lymphoma, 2 with mesothelioma, 9 with esophageal carcinoma, 1 patient each with metastatic cancer to chest wall and carcinoid, and 14 patients with benign pulmonary and esophageal lesions. Sensitivity was only 24% for urine samples from patients with demonstrable cancer. False-positive rates were 6% and 12% for urine samples from patients with benign lesions and those without evidence of residual cancer following treatment, respectively. Although elevated levels of UGF are present in some patients with pulmonary and esophageal cancer it is neither sensitive nor specific enough for use as a tumor marker.