Endocrine Abstracts

Background: Through this study, we hoped to better understand the factors affecting recurrence-free survival in patients who have undergone curative intent resection for small bowel neuroendocrine tumors (SB-NETs). Extensive literature exists on recurrence predictors for pancreatic NETs but not for those of the small bowel. We hope to bridge this gap.

Methods: We retrospectively evaluated patients who had received their index curative-intent operation for a small bowel neuroendocrine tumor at the Mayo Clinic (Rochester) from 2013-2017. Patients with distant metastases and those who had residual disease after resection were excluded. Descriptive statistical analysis was performed. Recurrence-free survival was estimated using Kaplan-Meier analysis and groups compared using log-rank test.

Results: Inclusion criteria were met in 122 patients. TNM stage was 1 or 2 (localized disease) in 25 patients (20.5%) and 3 (regional disease) in 97 patients (79.5%). Multifocal disease was present in 55 patients (45.1%). Symptomatic disease was present in 80 patients (65.6%). The most common symptoms were obstruction and Gl bleeding, which were seen in 16 (13.1%) and 21 (17.2%) patients, respectively. Overall, 5-year recurrence-free survival was 87% (95% CI 81-93). When stratified by extent of disease, 5-year recurrence-free survival was 95% (95% CI 87-100) for localized (stage 1-2) disease and 84% (95% CI 77-92) for regional (stage 3) disease (P=0.07). When stratified by tumor size, 5-year recurrence-free survival was 94% (95% CI 89-99) for tumors <2 cm and 66% (95% CI 50-86) for tumors >2 cm (P<0.001).

Conclusions: In this preliminary study, recurrence risk after curative-intent resection of small bowel neuroendocrine tumors was low and was associated with tumor size and extent of disease. This data can be used to accurately counsel our patients in the future and provide optimal follow-up recommendations after curative intent resection.

Abstract ID 21565