Thrombotic risk in gastroenteropancreatic neuroendocrine tumor patients: a single-center experience

BACKGROUND: Only scanty specific studies are available on venous thromboembolism (VTE) in neuroendocrine neoplasms (NEN). We retrospectively assessed the incidence of VTE in gastroenteropancreatic (GEP) NEN patients. METHODS: Between 2000 and 2016, GEP-NEN patients were retrospectively evaluated for VTE. Major thrombotic events included deep venous thrombosis (DVT) and pulmonary embolism (PE). 160 patients were included. The primary tumor site was: the gut in 99, pancreas in 54, and unknown in 7. A total of 93 patients had grade (G) 1 tumor, 36 G2, 4 G3; G was not available in 27 patients. TNM stage was I in 76 patients, II in 17, III in 23, and IV in 44. RESULTS: Twelve patients developed VTE: 9 had DVT and 3 PE. The primary site of the tumor was located in the pancreas in 9 patients, in the gut in 2, and it was unknown in one patient. Two patients had a functioning tumor. Grading was G1 in 3 patients, G2 in 6, G3 in 2 cases, and not available in one. The TNM stage was IV in 5 patients, III in 2, II in 3, and I in 2. Two patients died during the study period, one of whom died from PE. CONCLUSION: GEP-NEN patients harbor a considerable risk of VTE, particularly high for pancreatic NEN patients, for patients with moderate-poorly differentiated neoplasms, and at an advanced tumor stage.