Cystic Pancreatic Neuroendocrine Tumors Represent a Distinct Clinical Entity with Less Aggressive Biological...

Area of Science:

• Endocrinology
• Oncology
• Gastroenterology

Background:

• Pancreatic neuroendocrine tumors (pNETs) uncommonly present as cystic lesions, with existing literature showing inconsistent findings regarding their characteristics and behavior.
• A knowledge gap exists concerning the clinicopathological features and biological behaviors of cystic pNETs.

Purpose of the Study:

• To investigate the clinicopathological features of cystic pNETs.
• To determine if cystic pNETs represent a distinct clinical entity by comparing them with solid pNETs.

Main Methods:

• Retrospective review of patients with pNETs who underwent surgical resection from January 2014 to April 2019.
• Collection and analysis of demographic, clinical, surgical, oncological, and histological characteristics of cystic and solid pNETs.

Main Results:

• Cystic pNETs (10.7% of cases) were more likely to be asymptomatic and nonfunctional than solid pNETs.
• No significant differences were observed in age, sex distribution, tumor size, MEN1 association, or tumor location between cystic and solid pNETs.
• Cystic pNETs showed a trend towards a lower Ki-67 index and reduced incidence of liver metastasis compared to solid pNETs, though not statistically significant.

Conclusions:

• Cystic pNETs appear to be more nonfunctional and indolent, exhibiting less aggressive biological behavior than their solid counterparts.
• These findings suggest that cystic pNETs may represent a distinct clinical entity.
• A conservative management approach should be considered for carefully selected patients with cystic pNETs.