Higher preoperative levels of pancreastatin are associated with significantly worse survival times among patients with surgically treated small bowel (SBNET) and pancreatic neuroendocrine tumors (PNETs), according to findings presented at the 7th Annual Neuroendocrine Tumors (NET) conference in Nashville, TN. The meeting was organized by the North American Neuroendocrine Tumors Society (NANETS).
Both median progression-free survival (PFS) and overall survival (OS) were “significantly better in patients with normal (n=46) versus elevated (n=84) preoperative pancreastatin levels,” said lead author Scott K. Sherman, MD, of the University of Iowa Carver College of Medicine in Iowa City, IA, and coauthors. Median PFS was 6.5 versus 1.7 years and 5-year OS was 88% vs 73%, respectively (P = 0.04), they reported.
The study included 98 patients with SBNET and 78 patients with PNETs. At a median follow-up of 3.8 years, 62% of patients had metastatic disease and patients in the SBNET group had significantly shorter PFS than those with PNET (2.0 vs. 5.6 years; P < 0.01), the authors reported. (Median OS was 10.5 years for PNETs and has not been reached among patients with SBNETS, they noted.)
After multivariate statistical adjustment for confounding variables, pre- and postoperative pancreastatin remained “independently predictive of worse PFS and OS” (P < 0.05 for PFS and OS), they reported.
Postoperative normalization of pancreastatin levels might also prove to be predictive of outcome, they added.
“Higher pancreastatin levels are significantly associated with worse PFS and OS in SBNETs and PNETs,” the coauthors concluded. “This effect is independent of age, primary tumor site, and presence of nodal or metastatic disease. Pancreastatin provides valuable prognostic information and identifies surgical patients at high risk of recurrence who could benefit most from novel therapies.”
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Preoperative neurokinin A did not correlate with PFS or OS, while preoperative serotonin correlated with PFS but not OS, they noted.
A separate 2008 study published by British researchers found that rapid rises in circulating pancreastatin after initiation of somatostatin analog (SSA) therapy is significantly associated with poor survival.1
NET Abstract #C30
- Stronge RL, Turner GB, Johnston BT, et al. A rapid rise in circulating pancreastatin in response to somatostatin analogue therapy is associated with poor survival in patients with neuroendocrine tumours. Ann Clin Biochem. 2008;45(6):560-566.