Elevated serum chromogranin A is detectable in patients with carcinomas at advanced disease stages

Chromogranin A (CgA), a marker of neuroendocrine cells and an indicator for neuroendocrine differentiation, is associated with a poor prognosis when detected in tumor tissue, based on immunohistochemical techniques. We sought to determine whether it is possible to detect elevated serum CgA in patients with commonly occurring carcinomas of non-neuroendocrine origin. CgA was measured in both random and serial serum specimens, using a serum CgA assay developed in our laboratory. Elevated levels of serum CgA were detected in patients with carcinoma of the prostate, breast, ovary, pancreas, and colon. Serum CgA levels in patients with all types of carcinoma appeared to parallel the changes of serum dominant tumor markers and were found in sera containing highly elevated tumor markers. Based on these preliminary findings, perhaps we should monitor CgA, in addition to the routinely used tumor markers, during the treatment of patients with carcinomas to determine if CgA is useful as a prognostic marker in carcinomas other than prostatic cancer.