Supplementary Material for: Elderly Patients with Metastatic Neuroendocrine Tumors Are Undertreated and Have Shorter Survival: The LyREMeNET Study

Introduction: The incidence of neuroendocrine tumors (NETs) is rising, especially in elderly patients. The elderly cancer population presents considerable challenges, yet little is known about the characteristics, treatment patterns, and outcomes of metastatic NET (mNET) patients. Methods: The Lyon Real-life Evidence in Metastatic NeuroEndocrine Tumors study (LyREMeNET, NCT03863106) included consecutive mNET patients, diagnosed between January 1990 and December 2017. The exclusion criteria were nonmetastatic NET, poorly differentiated neuroendocrine carcinoma, and mixed neuroendocrine-nonneuroendocrine neoplasms. We aimed to compare patients ≥70 years old to patients <70 years old. Results: A total of 866 patients were included, 198 (23%) were ≥70 years old. There was no significant difference in characteristics except that elderly patients had synchronous metastasis more frequently. Elderly patients received significantly fewer treatments (median of 2.0 vs. 3.0 lines, respectively, p < 0.0001), were significantly less frequently treated by chemotherapy (32 vs. 54%), targeted therapy (16 vs. 30%), peptide receptor radionuclide therapy (5 vs. 16%), and they underwent significantly less frequently locoregional intervention. Median overall survival was significantly shorter in elderly patients (5.2 vs. 9.6 years). The most frequent cause of death was related to disease progression (71%). Multivariate analysis found that, after adjustment for tumor location, tumor grade, and number of metastatic sites, age remained significantly associated with overall survival (HR 1.66, 95% CI 1.26–2.18), indicating a poorer survival in patients ≥70 years old in comparison with younger patients (p = 0.0003). Conclusion: Patients ≥70 years old have a worse survival, die frequently from their disease, and are undertreated compared to younger patients.