Pro-gastrin-releasing peptide (Pro-GRP), a tumor marker for small cell lung cancer.

Gastrin-releasing peptide (Pro-GRP), a member of the bombesin family of peptides, has been shown to have mitogenic activity in small cell lung carcinoma (SCLC), and to be produced by SCLC in an autocrine fashion. We investigated the usefulness of serum pro-gastrin-releasing peptide (Pro-GRP) as a tumor marker for diagnosis, treatment and monitoring of patients with small cell lung cancer (SCLC).This study comprised 80 healthy individuals. Serum samples were also obtained from 80 patients with small cell carcinoma, 20 with chronic bronchitis, 30 with sarcoidosis and 20 with lung fibrosis. The cut-off level of serum Pro-GRP was set at 34.2 pg/ml.The levels of Pro-GRP in the patients with benign diseases were significantly higher than those in the healthy group. The serum Pro-GRP levels were elevated in SCLC patients. The elevation was significantly higher than that of the benign reference group.These results show that Pro-GRP may be a potential tumor marker for small cell lung carcinoma.