Chilean experience using “Theranostics” for treating metastatic neuroendocrine tumors with [177Lu]Lu DOTA-TATE

Abstract

Introduction: Well-differentiated, Neuroendocrine Tumors (NET) are highly heterogenic and slow-growing pathologies, characterized by unspecific symptomatology and elevated expression of somatostatin receptors (SSTR). Despite the high incidence of NETs, several patients are diagnosed in advance stages of the disease when surgery is insufficient to treat the pathology. Peptide receptor radionuclide therapy (PRRT) has emerged as a new state-of-the-art treatment for NET-patients in advanced stages. Results: In this retrospective study, between 2004 and 2018 a total of 66 patients with advanced-stage-NETs, refractory to other therapies, were treated with [177Lu]Lu DOTA TATE. At the end of the study, 56.1% of the patients were alive and the median overall survival for all patients in the study was 86.3 months. Patients that received doses ≥ 22.2 GBq showed increased overall survival (OS) in comparison with patients that received doses < 22.2 GBq (HR, 0.168; 95%CI 0.12- 0.99; p<0.001), adjusted by gender. Likewise, patients that received doses ≥29.6 GBq had an increased OS (HR, 0.42; 95%CI 0.19-0.94, p<0.05). Conclusion: Although several studies have shown that PRRT is an effective alternative for advanced NET, patients in South America have no regular access to PRRT. Our study proves that [177Lu]Lu-DOTA-TATE effectively increases the survival of patients with metastatic NET and provides an excellent alternative in terms of cost-efficiency for South American countries.