Characteristics and treatment options of glucagonomas: a national study from the French Group of Endocrine Tumors and ENDOCAN-RENATEN network.

ABSTRACT

OBJECTIVE: Glucagonoma is a very rare functional pancreatic neuroendocrine tumor (PanNET). We aimed to provide data on the diagnosis, prognosis, and management of patients with glucagonoma. DESIGN AND METHODS: In this retrospective national cohort, we included all patients with glucagonoma, defined by at least 1 major criterion (necrolytic migratory erythema [NME] and/or recent-onset diabetes, and/or weight loss ≥ 5 kg) associated with either glucagonemia > 2 × upper limit of normal or positive glucagon immunostaining. Antisecretory efficacy was defined as partial/complete resolution of glucagonoma symptoms. Antitumor efficacy was assessed according to the time to next treatment (TTNT). RESULTS: Thirty-eight patients were included with median age 58.7 yo, primary PanNET located in the tail (68.4%), synchronous metastases (63.2%). Median Ki-67 index was 3%. Most frequent glucagonoma symptoms at diagnosis were NME (86.8%), weight loss (68.4%), and diabetes (50%). Surgery of the primary PanNET was performed in 76.3% of cases, mainly with curative intent (61.5%). After surgery, complete resolution of NME was seen in 93.8% (n = 15/16). The secretory response rates were 85.7%, 85.7%, 75%, and 60% with surgery of metastases (n = 6/7), chemotherapy (n = 6/7), liver-directed therapy (n = 6/8), and somatostatin analogs (n = 6/10), respectively. All lines combined, longer TTNT was reported with chemotherapy (20.2 months). Median overall survival (OS) was 17.3 years. The Ki-67 index > 3% was associated with shorter OS (hazard ratio 5.27, 95% CI [1.11-24.96], P = .036). CONCLUSION: Patients with glucagonoma had prolonged survival, even in the presence of metastases at diagnosis. Curative-intent surgery should always be considered. Chemotherapy, peptide receptor radionuclide therapy, or liver-directed therapy seems to provide both substantial antitumor and antisecretory efficacies.