Diagnostic characteristics, treatment outcomes, and prognostic factors in glucagonomas.

Objective: Glucagonomas are rare islet cell tumours, accounting for 2% of such tumours, with an annual incidence of 0.01-0.1 per million. This study aimed to describe diagnostic characteristics and treatment outcomes in patients with glucagonoma from a major referral centre.

Design: A retrospective case series included patients diagnosed with glucagonoma at the ENETS Centre of Excellence, Royal Free Hospital, London, UK.

Methods: Electronic patient records were reviewed to document baseline disease characteristics and treatment outcomes. Disease-free survival (DFS), progression-free survival (PFS), and overall survival (OS) were calculated using the Kaplan-Meier method.

Results: Twenty patients (75% male, age 56.6 ± 11.6 years, mean Ki-67 index 7.3 ± 7, mean ± SD) were included; 50% had liver metastases at diagnosis. The median OS was 34 months (95% CI: 30.3-37.7). Median OS was 34, 9, and 71 months for patients with liver, lung, and skeletal metastases, respectively. At diagnosis, migratory necrolytic erythema was linked to poorer OS (22 months, 95% CI: 14.3-29.7). Median DFS following surgery was 25 months (95% CI: 3.5-46.5). For inoperable disease, Lutetium-177 (¹⁷⁷Lu)-DOTATATE peptide receptor radionuclide therapy (PRRT) demonstrated efficacy in disease control. Other treatments included somatostatin analogues, chemotherapy, and molecular-targeted agents.

Conclusion: Tumour grade, metastases, and NME at diagnosis influence OS in glucagonoma. Surgery is associated with the best PFS as first-line therapy, while ¹⁷⁷Lu-DOTATATE PRRT effectively controls disease progression. Further studies are needed to optimise treatment sequencing for advanced glucagonoma.