Purpose: No reliable biomarkers are currently available for pancreatic neuroendocrine tumors (PanNETs). Vasostatin-1 (VS-1), the N-terminal fragment of Chromogranin A (CgA), seems to a more reliable biomarker compared to its precursor. Primary aim of this study was to investigate the ability of VS-1, compared to total-CgA, to assess the effectiveness of surgical resection performed for NF-PanNETs. Secondary aim was to evaluate two additional CgA-derived fragments, pancreastatin (PST) and vasostatin-2 (VS-2) as possible biomarkers for NF-PanNETs. Method: Consecutive patients who underwent surgery for sporadic NF-PanNETs between May 2018 and October 2019 were included. Plasma levels of CgA and CgA-derived fragments were measured by Enzyme-Linked ImmunoSorbent Assay (ELISA), preoperatively and on postoperative day 5 (POD5). Results: Preoperative VS-1 was significantly higher compared to VS-1 measured on POD5 (pre: 0.338 nM versus POD5: 0.147 nM, P<0.001), whereas total-CgA plasma levels significantly increased after surgery (pre: 1.123 nM versus POD5: 1.949 nM, P=0.006). The proportion of patients with VS-1 plasma levels greater than a previously defined cut-off (0.390 nM) significantly decreased from preoperative time (15/35, 43%) to POD5 (2/35, 6%) (P<0.001). No statistically significant differences in terms of PST (P=0.870) and VS-2 (P=0.909) plasma levels were observed between preoperative and postoperative time. Conclusion: VS-1 seems able to provide an early assessment of surgical efficacy in patients submitted to surgery for NF-PanNETs, whereas total-CgA, PST and VS-2 have no clinical utility in this setting.