Prognosis of neuroendocrine tumor patients with carcinoid heart disease undergoing Peptide Receptor Radionuclide Therapy – does the heart matter? – PRRT in carcinoid heart disease – does the Tricuspid valve insufficency matters

Introduction: Patients with carcinoid heart disease (Hedinger’s syndrome, HS) have two times lower survival probability as compared to patients without cardiac involvement. The aim of this study was to investigate if the severity of the tricuspid valve insufficiency influence the efficacy of Peptide Receptor Radionuclide Therapy (PRRT) in neuroendocrine tumor patients. Methods: 42 (7.6%; mean age 59 years, F: M 19: 23) out of 550 patients with progressive neuroendocrine tumors (NET) treated at our neuroendocrine tumor center with PRRT using radiolabeled somatostatin analogs (Yttrium–90 or Lutetium–177 DOTA-TATE) were found to have HS as confirmed by 2D echo and CW Doppler. Response to PRRT was assessed by Gallium–68 SMS receptor PET/CT. Results: 16 patients had grade 1, 8 had grade 2, 4 had grade 3 and 13 patients had grade 4 tricuspid valve regurgitation (TR). 9/42 (21%) patients died. Median/mean survival from the time of first diagnosis (ToFD) in high grade TR group (grade 3 and 4) was 146/123 months whereas mean survival time for low grade (1 and 2) TR was 233 months from ToFD. Mean survival in patients with high grade TR was found to be 33.8 months from the time of first PRRT (incidence of death 42.2%) vs. 69.3 months for low grade TR (incidence of death 7%). Patients treated with ≥ 3 cycles of PRRT achieved SD in 50% while the remaining 50% had PD. The incidence of disease progression was 6 to 7 times higher than GEP NET patients. Six patients showed improvement in TR after PRRT (all with grade 1). 8 patients with grade 3/4 TVR underwent tricuspid valve replacement (3 patients with very advanced disease died immediately after surgery). Conclusion: NET patients treated with PRRT having high grade HS have two times lower survival probability as compared to patients with low grade HS. 2D echocardiography must be regularly performed in NET patients in order to detect carcinoid heart disease at an early stage and employ surgical intervention timely. carcinoid heart disease - neuroendocrine tumors - peptide receptor radionuclide therapy - tricuspid valve insufficiency