Fasting human pancreatic polypeptide (HPP) levels are similar in patients with type 2 diabetes, chronic pancreatitis, and pancreatic ductal adenocarcinoma, regardless of their glycemic status, according to a study published in Pancreas, making them an inadequate diagnostic biomarker.
Patients with diabetes that results from pancreatic disorders have been described by the term type 3c diabetes mellitus, and the condition is often misdiagnosed as type 2 diabetes. To determine whether fasting HPP levels could be used as a biomarker to distinguish between these conditions, the study set out to compare the fasting HPP levels of patients with chronic pancreatitis and pancreatic ductal adenocarcinoma, stratified by diabetes status with new onset type 2 diabetes and healthy controls. Fasting HPP levels of patients with type 3c diabetes were also compared with patients with type 2 diabetes.
The study included 250 subjects who were enrolled in the Mayo Clinic Specialized Program of Research Excellence database for pancreatic cancer. There were 50 individuals in the chronic pancreatitis group, 50 in the pancreatic ductal adenocarcinoma with new-onset diabetes mellitus group, 50 in the pancreatic ductal adenocarcinoma without diabetes group, 50 in the new-onset type 2 diabetes group, and 50 healthy controls without diabetes. Patients in the chronic pancreatitis group were broken down into those without diabetes (n=34) and those with diabetes (n=16).
The median levels of fasting HPP were similar between all groups, including healthy controls. Consequently, study investigators conclude “that fasting levels of HPP cannot be used to distinguish [pancreatic ductal adenocarcinoma with new-onset diabetes mellitus] from new-onset [type 2 diabetes mellitus] as well as type 3c [diabetes mellitus]. Pancreatic polypeptide response to mixed meal may be a better biomarker to help distinguish type 3c [diabetes mellitus] from underlying [pancreatic ductal adenocarcinoma] and [chronic pancreatitis], as well as from type 2 [new-onset diabetes mellitus], and act as the second ‘sieve’ to enrich a population that can then be targeted for screening for [pancreatic ductal adenocarcinoma].”
Nagpal SJS, Bamlet WR, Kudva YC, Chari ST. Comparison of fasting human pancreatic polypeptide levels among patients with pancreatic ductal adenocarcinoma, chronic pancreatitis, and type 2 diabetes mellitus [published online May 17, 2018]. Pancreas. doi: 10.1097/MPA.0000000000001077