Utility of chromogranin B compared with chromogranin A as a biomarker in Japanese patients with pancreatic neuroendocrine tumors.
Objective
Currently, serum chromogranin A is a well-established biomarker for pancreatic neuroendocrine tumors; however, other pancreatic diseases, oral use of a proton pump inhibitor and renal impairment can affect chromogranin A. Meanwhile, chromogranin B, belonging to the same granin family as chromogranin A, is not fully examined in these conditions. The present study aimed to evaluate the utility of chromogranin B as a pancreatic neuroendocrine tumor biomarker.


Methods
Serum chromogranin B levels were determined by radioimmunoassay and serum chromogranin A levels by enzyme-linked immunosorbent assay in pancreatic neuroendocrine tumor (n = 91) and other pancreatic conditions, and in healthy people (n = 104), to assess the relationships with clinical features.


Results
The diagnostic ability of chromogranin B was as good as chromogranin A. The area under the curve was 0.79 for chromogranin B (sensitivity/specificity: 72%/77%), and 0.78 for chromogranin A (sensitivity/specificity: 79%/64%). Chromogranin B was not affected by proton pump inhibitor use and age, which affected chromogranin A. The number of cases without liver metastases was larger in pancreatic neuroendocrine tumor patients with positive chromogranin B and negative chromogranin A. Though chromogranin A significantly elevated cases with proton pump inhibitor treatment and had positive correlation with age, chromogranin B did not have the tendencies. However, both chromogranin B and chromogranin A elevated in the case with renal impairment. In addition, the logistic regression analysis showed that chromogranin B was superior to chromogranin A in differentiation of pancreatic neuroendocrine tumor from other pancreatic diseases.


Conclusions
Compared with chromogranin A, chromogranin B may be more useful during proton pump inhibitor treatment and can detect tumors without liver metastases. In addition, chromogranin B may be an excellent biomarker when differentiation of pancreatic neuroendocrine tumor from other pancreatic diseases is required.
['Miki|Masami|M|', 'Ito|Tetsuhide|T|', 'Hijioka|Masayuki|M|', 'Lee|Lingaku|L|', 'Yasunaga|Kohei|K|', 'Ueda|Keijiro|K|', 'Fujiyama|Takashi|T|', 'Tachibana|Yuichi|Y|', 'Kawabe|Ken|K|', 'Jensen|Robert T|RT|', 'Ogawa|Yoshihiro|Y|']
D000328:Adult D000367:Age Factors D000368:Aged D000369:Aged, 80 and over D014408:Biomarkers, Tumor D016022:Case-Control Studies D053379:Chromogranin A D053378:Chromogranin B D004797:Enzyme-Linked Immunosorbent Assay D005260:Female D005755:Gastrins D006801:Humans D016015:Logistic Models D008297:Male D008875:Middle Aged D015999:Multivariate Analysis D018358:Neuroendocrine Tumors D010190:Pancreatic Neoplasms D054328:Proton Pump Inhibitors D012372:ROC Curve D055815:Young Adult
chromogranin B chromogranin A pancreatic neuroendocrine tumors pancreatic diseases