Plasma ghrelin levels may be biomarkers for gastric cancer survival

Last Updated: 2017-01-19

By Lorraine L. Janeczko

NEW YORK (Reuters Health) - In patients with gastric cancer (GC), plasma ghrelin levels may be a biomarker for survival, but the relationship is different for pre- and post-operative measures, new research from Iran suggests.

"Previous laboratory studies have shown that ghrelin can modulate the growth of cancer cells positively or negatively," explained Dr. Max W. Sung, an associate professor of medicine, hematology and medical oncology at the Icahn School of Medicine at Mount Sinai in New York City, who was not involved in the work.

"Depending on the cancers tested, high levels of tumor tissue ghrelin has been shown to be associated with survival: increased in breast cancer, decreased in kidney cancer, and similar in lung cancer," he told Reuters Health by email.

For the study, online January 5 in Clinical and Translational Gastroenterology, Dr. Kazem Zendehdel of Tehran University of Medical Sciences and colleagues enrolled 81 GC patients having curative gastrectomy with or without neoadjuvant chemotherapy at one center. They followed the patients for up to three years.

Before surgery, patients in the second and third quartiles of total ghrelin levels had significantly worse survival than those in the lowest quartile (hazard ratio, 2.67 and 2.32, respectively). There was no significant survival difference between the highest and lowest quartiles, though.

Ghrelin levels dropped significantly after gastrectomy. Patients with post-op total ghrelin below the median (HR, 2.33) or the 25th percentile (HR, 4.29) both had significantly worse survival than those with higher levels.

The researchers observed similar patterns for active ghrelin.

Other prognostic factors associated with poorer survival included advanced tumor-node-metastasis stage (HR, 4.88), cachexia (HR, 2.99), and receiving no neoadjuvant chemotherapy (HR, 2.02). However, the "prognostic effects of plasma ghrelin in gastric cancer are independent of stage, grade, and cachexia," the researchers note.

Dr. Harry H. Yoon, an assistant professor of oncology at the Mayo Clinic in Rochester, Minnesota, said the findings are unlikely to affect patient care at this point.

"This is an interesting exploratory study," said Dr. Yoon, who was not involved in the study. "Its main finding - that low postoperative plasma ghrelin levels are associated with worse survival - needs confirmation in larger cohorts."

Dr. Sung added, "It will be of great interest to see future studies looking at the benefits of administering drugs mimicking ghrelin in cancer patients to determine if survival can be affected, although such drugs are not approved by the FDA in humans."

The authors recommend further studies with longer follow-up period and considering H. pylori infection status.

Dr. Zendehdel did not respond to requests for comment.

SOURCE: http://bit.ly/2jCuHNa

Clin Transl Gastroenterol 2017.