Dam G, Grønbæk H, Sorbye H, et al. - In neuroendocrine tumor (NET) patients with disseminated disease, the authors prospectively examined whether changes in plasma chromogranin A (CgA) was correlated with tumor burden changes. Between 2010-2013, 239 patients from five NET centers were included. Only a weak association was observed between change in plasma CgA and change in tumor burden in this prospective study of GEP-NET patients. Therefore, CgA was ineffective as a single biomarker to predict tumor progression.