Active Surveillance May Benefit Certain Patients With Small Nonfunctional Pancreatic NETs

Active Surveillance May Benefit Certain Patients With Small Nonfunctional Pancreatic NETs

Results from a retrospective review demonstrated significant increases in the use of observation in patients with small nonfunctional pancreatic neuroendocrine tumors (NF-pNETs) from 2015 to 2020, as published in JAMA Surgery.

In this retrospective review of the National Cancer Database, among 10,227 patients (mean age, 61.5 years; 51.3% men) with NF-pNETs, overall observation increased from 16.4% in 2010 to 44.7% in 2020 (P < .001). In tumors sized 1 cm or smaller, the use of observation increased from 18.5% in 2010 to 52.0% in 2020 (P < .001). For tumors sized between 1.01 cm and 2 cm, observation rates increased from 15.4% in 2010 to 41.9% in 2020 (P < .001). Researchers also found that patients seen at academic centers were more likely to undergo observation compared with those seen at nonacademic centers.

“These findings highlight a growing nationwide trend in the initial nonoperative management of small NF-pNETs,” study authors wrote. “As most patients with small NF-pNETs still undergo resection despite its associated morbidity and unclear survival advantage, research should focus on whether barriers exist to adopting active surveillance in specific patient populations.”

Additionally, in the 5579 patients with localized pNETs 2 cm and smaller, 2027 (36.3%) patients underwent observation during 2015 and 2020, whereas 3552 (63.7%) patients from this group underwent resection during those years.

Upon multivariable analysis, several factors were associated with the use of observation including increasing age, later year of diagnosis, and treatment at an academic center. Factors associated with surgery included female sex, further distance traveled, tumor size between 1.01 cm and 2.00 cm, and pancreas body/tail tumors.

This study assessed the nationwide trends during the use of observation for pNETs sized 2 cm and smaller and performed a multivariate analysis to determine the factors associated with resection.

Eligible patients were aged 18 years and older and diagnosed with NF-pNETs between 2010 and 2020 at facilities treating 3 or more pNETs per year of any size. “This cutoff represented the top quartile of facilities and helped avoid biased results from centers with little experience managing pNETs,” the study authors wrote.

NF-pNETs are commonly diagnosed by chance in adults, according to the study’s introduction. Although many NF-pNETs remain clinically indolent (no symptoms), some may reveal a tendency to spread.

Currently, experts are uncertain of the metastatic potential of NF-pNETs, and the potential morbidity linked with pancreatic surgery, as noted in the study. This may be associated with patients opting for surgery vs active surveillance, although recent guidelines endorse the use of active surveillance backed by retrospective data.

The study’s main limitation was a lack of availability of information in the National Cancer Database pertaining to why surgery or observation was selected (eg, patient preference, symptoms, tumor grade). Information was also unavailable regarding whether a patient changed from observation to surgery during follow-up.

“Further research on the long-term efficacy of active surveillance, cost-effectiveness strategies, and further refining patient-related risk factors other than tumor size will ultimately guide the evidence-based and personalized management of small NF-pNETs,” study authors concluded.

Reference

Ruff SM, Dillhoff M, Tsai S, et al. Trends in the Use of Observation for Small Nonfunctional Pancreatic Neuroendocrine Tumors. JAMA Surg. Published online August 21, 2024. doi:10.1001/jamasurg.2024.2243