Incidence and factors associated with heart disease in patients diagnosed with small bowel and broncho-pulmonary neuroendocrine tumors: a population-based analysis

Background — Heart disease is a complication of neuroendocrine tumors (NETs). Little is known about its occurrence in all patients diagnosed with NETs. We examined the occurrence of valvular and congestive heart disease and the use of echocardiography after NETs diagnosis.

Methods — We conducted a population-based retrospective cohort study of small bowel and broncho-pulmonary NETs (2000–2019). Heart disease was defined as new congestive heart failure or valvular disease. Cumulative incidence functions (CIF with 95 %CI) of heart disease and use of echocardiography were computed accounting for the competing risk of death.

Results — Of 5735 patients with NETs, 54.1 % had small bowel primaries and 48.8 % metastatic disease. The CIF of heart disease in all patients was 10.7 % (9.8–11.7 %) at 10 years. Heart disease was more frequent for small bowel (10-year CIF 12.7 % [11.2–14.2 %]) than broncho-pulmonary (10-year CIF 9.1 % [8.0–10.3 %]) NETs. Of 1864 patients with available urinary 5HIAA data, 64.0 % had elevated results. Heart disease was more frequent with elevated serotonin (10-year CIF 13.5 % [11.3–15.9 %]). 10-year CIF for echocardiography in all patients was 64.7 % (63.3–66.1 %), and exceeded 50 % in all sub-groups. Patterns of echocardiography CIF mirrored those of heart disease.

Conclusions — Valvular and congestive heart disease occurred in 10 out of 100 patients in the 10 years after small bowel and broncho-pulmonary NETs diagnosis. Patterns of echocardiography use suggest that testing is not influenced by NET disease characteristics, with risks of under-detection in at-risk individuals.