Determining Prognosis in Patients With Carcinoid Syndrome: A Retrospective Single-Center Cohort Study

Carcinoid syndrome (CS), the most prevalent neuroendocrine tumor (NET)-related hormonal syndrome, is associated with impaired survival. However, the contribution of NET-specific death in patients with this syndrome is currently unknown. This study aimed to evaluate overall survival (OS), prognostic factors, and causes of death in patients with CS.

We retrospectively included patients with CS treated between 1995 and 2021 at our ENETS Center of Excellence. We used Kaplan-Meier curves and log-rank tests to perform survival analyses, and a Cox proportional hazards model to calculate mortality hazard ratios (HRs).

A total of 295 of 427 included patients with CS died during follow-up, and cause of death was recorded in 255 patients. In 231 (90.6%) patients, the cause of death was NET-specific. Median OS was 7.1 years, and 65.1% and 34.1% of CS patients were alive at 5 and 10 years, respectively. Multivariate analysis identified age (HR, 1.06; P<.001), WHO tumor grade 2 (HR, 2.11; P=.01), plasma chromogranin A (CgA) level of 200 to 940 µg/L (HR, 1.64; P=.04), CgA level >940 µg/L (HR, 3.18; P<.001), and primary lung NET (HR, 1.77; P=.008) as negative predictors of survival. The presence of carcinoid heart disease (HR, 1.01; P=.97) was not associated with OS in a multivariate model due to interaction with CgA levels.

Patients with CS are likely to succumb to their disease, with >90% of mortality being NET-specific. Age, tumor grade, primary lung origin, and CgA levels were independent predictors of mortality. These findings indicate that there is an urgent need for advances in therapeutic options for patients with CS.