|
|
Back to 2014 Annual Meeting Abstracts
Surgical Resection Provides a Significant Overall Survival Benefit for Patients With Small Pancreatic Neuroendocrine Tumors
Susan Sharpe*1, Haejin in1, David P. Winchester3, Mark Talamonti2,1, Marshall Baker2,1
1Surgery, University of Chicago, Chicago, IL; 2Surgery, NorthShore University HealthSystems, Chicago, IL; 3American College of Surgeons, Chicago, IL
Background
Pancreatic neuroendocrine tumors (PNETs) have a widely variable potential for malignant behavior. Most series examining the efficacy of surgical resection of these tumors are underpowered, single institutional, retrospective studies. There continues to be controversy regarding the optimal management of incidentally discovered small (≤ 2 cm) non-functioning PNETs. We evaluated the sub-population of small, non-functional PNETs in the National Cancer Data Base (NCDB) to determine if an aggressive surgical approach provides a significant survival advantage over observation.
Methods
The National Cancer Data Base was queried to identify all patients with PNETs ≤ 2cm in size treated between 2003 and 2011. Patients with metastatic disease at the time of presentation and those with unknown histologic grade were excluded. Kaplan-Meier analysis, stratified by histologic grade and treatment type, was used to evaluate the difference in 5-year overall survival (OS) between patients who received surgery and those who did not. Multivariable Cox regression was used to determine the relative importance of surgical intervention in overall survival.
Results
749 patients met inclusion criteria. 93.2% underwent surgery and 6.8% were managed with observation alone. 24.7% were size 0-1 cm and 75.3% were 1.1-2 cm. There were no significant differences between patients in the surgical and observation cohort with regard to tumor size, tumor location, or comorbid disease characteristics. A greater percentage of patients in the observation cohort had moderately or poorly differentiated tumors than did patients in the surgical cohort (37.3% vs. 11.3%, p<0.05). Five-year OS was 89.6% for patients who underwent surgery and 40.1% for those who did not (p<0.0001). Variables included in the final multivariate Cox model were selected by backwards selection and included: age, Charlson score, tumor location, histologic grade, and treatment (surgery vs. observation). When controlling for Charlson score, age, and tumor location, observation without surgical resection (OR 4.94, 95% CI [2.79, 8.76]) and poorly differentiated histology (OR 8.15, 95% CI [4.47, 14.85]) were independently associated with a significant increase in the risk of death (p<0.0001). Lymph node positivity and tumor size were not associated with an increased risk of death.
Conclusion
In patients with localized, non-functional pancreatic neuroendocrine tumors 2 cm in size or smaller, surgical resection provides a significant overall survival advantage over observation. This benefit is independent of patient age, co-morbid status, and histologic grade of the tumor.
Back to 2014 Annual Meeting Abstracts
|
