
A spotlight on Chromogranin A
What is Chromogranin A? Chromogranin A (CgA) is an acidic protein released along with catecholamines from chromaffin cells and nerve terminals. This statement alone might explain why it's a good marker to use with Neuroendocrine Neoplasms. It is said to be a measure of tumour bulk. Depending on the test kit being used, you may also see test results for Chromogranin B (CgB) alongside CgA. CgB is said to be less affected by false positives and forms a useful adjunct to the more established chromogranin A measurement. The brand of test kit which includes CgB tends to be confined to Europe. Immunohistochemical Testing. CgA is one the most commonly used immunohistochemical (IHC) markers for neuroendocrine cells and their tumours. You may find the mention of CgA in your biopsy reports…