Original Research ArticleSmall-sized gastrointestinal stromal tumors: Is there an association between expectant management and overall survival?
Introduction
With the increase in the use of endoscopy and axial imaging to evaluate vague abdominal symptomatology, there has been an increase in the discovery of small gastrointestinal stromal tumors (GISTs).1 While these tumors are typically low grade with very limited potential for aggressive behavior, many are referred for surgical resection. The most recent guidelines from the National Comprehensive Cancer Network (NCCN) recommend resection of very small gastric GISTs in patients that are symptomatic or have high-risk features (irregular borders, echogenic foci or sonographic heterogeneity) on endoscopic ultrasound (EUS).2 Non-gastric GIST are thought to be characterized by a higher potential for disease progression, and these tumors are uniformly resected regardless of symptoms or radiographic features. For patients without high-risk features on EUS, the NCCN recommends interval surveillance by either serial EUS or axial CT or MR imaging. The evidence supporting these NCCN guidelines is sparse with the best available clinical studies including relatively few patients managed expectantly and relatively few patients with small but moderate to high grade tumors. Although complete resection of very small GISTs is thought to be curative, the actual overall survival benefit of resection over expectant management (EM) remains to be determined.3
We queried the National Cancer Data Base (NCDB) in an effort to identify factors associated with use of EM for GIST ≤3CM and to compare survival outcomes between patients with small-sized tumors who underwent curative resection to those undergoing EM. Our hypothesis was that patients with non-gastric GISTs would be less likely to be managed with surveillance only and that there would be no significant difference in survival between patients who underwent surgery and patients who did not.
Section snippets
Data source, sample selection, and variables examined
The National Cancer Data Base (NCDB) is a facility-based dataset that is a joint project of the American Cancer Society and the Commission on Cancer (CoC) of the American College of Surgeons (ACS).4 The NCDB captures an estimated 70% of newly diagnosed cancers being treated in the United States annually at nearly 1500 accredited hospitals. The ACS and CoC have not reviewed and are not responsible for the statistical analysis and conclusions discussed in this manuscript. This project was
Univariate analysis of patient outcomes by treatment approach
1330 patients met inclusion criteria. 966 (72.6%) patients had tumors located in the stomach; 304 (22.9%) patients had small bowel tumors; 43 (3.2%) patients had colonic tumors; 17 (1.3%) patients had rectal tumors. 1196 (89.9%) underwent surgical resection; 134 (10.1%) EM. Of those undergoing resection, 884 had a recorded histologic grade with 861 (97.4%) having low-grade tumors. 1270 (95.5%) patients received histologic confirmation of their tumors either by surgical pathology, preoperative
Discussion
In this study, we report the largest comparison to date of EM and resection for GISTs ≤3CM. While sex and insurance status were both found to be associated with overall survival, there was no statistical difference in overall survival between those patients undergoing resection and those undergoing observation for GIST ≤3CM. This trend was consistent ever after matching for covariates that would be expected to impact overall survival.
There is one finding from our results that ran counter to our
Conclusion
We report the largest and most contemporary comparison between EM and resection for GISTs ≤3CM. Despite the inherent limitations, we find that patients who received EM had no statistically significant reduced overall survival compared to patients who underwent resection. The decision to operate on tumors within this size category should be made after consideration for symptomatic status and imaging features.
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Cited by (1)
Impact of Tumor Size and Management on Survival in Small Gastric Gastrointestinal Stromal Tumors
2023, Journal of Gastrointestinal Surgery