519PCarcinoid heart disease (CHD): the CRUSOE-NETs, a prospective cohort study from the French group of endocrine tumours (GTE)

Abstract Background Neuroendocrine tumors (NET) represent a heterogeneous group of rare tumors, some of them secreting serotonin resulting in the carcinoid syndrome (CS). CHD is an integral part of this syndrome but remains poorly understood. The GTE is conducting a national survey of patients at risk for CHD aiming at evaluating the occurrence & progression rates of CHD, the frequency & results of cardiac surgery, and patient outcomes as well as the role of clinical characteristics and biomarkers as predictive markers; 600 patients are expected over a 5-year period with a 10-year follow-up. We herein present the study status at one year. Methods Patients with a metastatic ileum or bronchial NET, or any NET with a CS or 5HIAA levels greater than at least twice the upper normal range, seen by a NET specialist and a referee cardiologist are eligible. Clinical, pathological, biological parameters and previous treatments are collected. A transthoracic echocardiography is realised at inclusion and at least every year. Results From March 2018 to March 2019, 167 patients from 8 centers were included. Median [range] time from NET diagnosis to study inclusion was 56 months [0-501]. Median age was 66 years [34-86] with a male preponderance (53%); 85% had ileum NETs, 8% lung NETs, and 7% other NETs with CS or elevated 5HIAA; 100% had metastatic disease. Most of them have been pretreated: somatostatin analogs 96%, surgery of primary tumor 81% or metastasis 34%, liver embolization 24%, peptide receptor radionuclide therapy 19%, chemotherapy 16%, targeted therapy 12%, radiofrequency ablation 6%, interferon 2%. At inclusion, 81 patients (49%) had a CS, 67% with flushing, 68% with diarrhea. CHD was documented in 22 (13%) patients, all of them had tricuspid disease and simultaneous pulmonary, mitral and/or aortic disease for respectively 13, 3 and 1 of them; 14 patients with CHD had a CS. Seven patients underwent cardiac surgery for CHD. Conclusions The first large prospective multicentric study about CHD is ongoing. Preliminary results confirm the feasibility of the study with nearly 170 patients included in one year and 13% of CHD. The inclusion of new patients and 10-year follow-up will allow a better knowledge of the current incidence, progression and prognosis of CHD. Clinical trial identification NCT03498040. Legal entity responsible for the study French Group of Endocrine Tumors (GTE). Funding IPSEN. Disclosure G. Cadiot: Advisory / Consultancy: Novartis; Advisory / Consultancy: Ipsen; Advisory / Consultancy: AAA; Advisory / Consultancy: Keocyt. P. Nazeyrollas: Honoraria (self), Honoraria (institution), Travel / Accommodation / Expenses, Non-remunerated activity/ies: Novartis; Honoraria (self), Non-remunerated activity/ies: MSD; Honoraria (institution): Sanofi; Honoraria (institution): novo-nordisk; Travel / Accommodation / Expenses, Non-remunerated activity/ies: actelion; Travel / Accommodation / Expenses, Non-remunerated activity/ies: Bayer; Non-remunerated activity/ies: Servier; Non-remunerated activity/ies: bms. P. Afchain: Travel / Accommodation / Expenses: Novartis; Travel / Accommodation / Expenses: Ipsen. F. Delelis: Honoraria (self): Novartis; Honoraria (self): boehringer. J. Forestier: Honoraria (self): Amgen; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Bayer; Honoraria (self), Speaker Bureau / Expert testimony, Research grant / Funding (institution): Ipsen; Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: Sanofi; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony: Merck; Honoraria (self): Servier. C. Lombard Bohas: Advisory / Consultancy: Ipsen; Advisory / Consultancy: Novartis; Advisory / Consultancy: Pfizer; Advisory / Consultancy: AAA. All other authors have declared no conflicts of interest.