# Insulin‐Dependence and Survival in Pancreatic Neuroendocrine Tumors: Results From the US‐NTSG Group

## TL;DR

This study finds that insulin-dependent diabetes is linked to worse survival outcomes in patients with pancreatic neuroendocrine tumors.

## Contribution

The study is the first to show that insulin dependence, but not non-insulin dependence, is independently associated with worse survival in PNET patients.

## Key findings

- IDDM patients had significantly lower 5-year cancer-specific survival compared to non-DM and NIDDM patients.
- On multivariate analysis, IDDM was independently associated with worse cancer-specific survival (HR 2.27).

## Abstract

PNETs are rare pancreatic malignancies originating from islet cells and exhibit a strong co‐occurrence with Diabetes Mellitus (DM), associated with worse survival outcomes. However, studies have yet to delineate the impact of insulin dependent (IDDM) and non‐insulin dependent (NIDDM) on poor oncological outcomes.

Utilizing the U.S. Neuroendocrine Tumor Study Group database (1999‐2016), we performed a retrospective cohort study of adult patients who underwent primary surgical resection of PNETs. Patients were categorized based on preoperative diagnosis into non‐DM, NIDDM, and IDDM cohorts. We used the Kaplan‐Meier method and log‐rank test to study cancer‐specific survival (CSS). Cox proportional Hazards models were used to assess the impact of IDDM on CSS.

Of the 1122 patients included in the analysis, 870 (77%) were non‐DM, 168 (15%) were NIDDM, and 84 (8%) were IDDM. The groups were similar in tumor stage and grade. However, they differed in sex, BMI, age, ASA class, tumor location, preoperative HbA1c, and serum glucose (p‐value < 0.05). Patients with IDDM had significantly decreased 5‐year CSS compared to patients without IDDM (CSS: IDDM 85%, NIDDM 94%, non‐DM 93%, NIDDM + non‐DM 93%; p < 0.01). On multivariate analysis, IDDM was independently associated with worse CSS (HR 2.27, 95% Confidence Interval 1.15−4.45, p = 0.02).

Insulin dependence is associated with worse cancer‐specific survival in PNET patients following surgical resection compared to PNET patients with NIDDM or without DM.