Comparing the long-term outcomes among patients with stomach and small intestine gastrointestinal stromal tumors: An analysis of the National Cancer Database.

BACKGROUND AND OBJECTIVES

Gastrointestinal stromal tumors (GIST) are the most common sarcoma arising from the gastrointestinal tract. Data regrading long-term prognosis based on tumor location (stomach vs small intestine) are mixed, so we aimed to analyze their outcomes using a large national oncology database.

METHODS

The National Cancer Database was queried for cases of stomach and small intestine GIST between the years 2004 and 2014. Survival analysis was performed using the Kaplan-Meier method, and factors related to survival were compared using the Cox proportional hazards model.

RESULTS

Of 18 900 total patients, those with small intestine GIST had larger median tumor size (6.2 cm; interquartile range [IQR], 3.8 to 10.0 vs stomach: 5.0 cm; IQR, 3.0 to 9.0; P < 0.001) and a higher incidence of tumors with ≥5 mitoses/50 HPF (29.3% vs stomach: 24.2%; P < 0.001). Unadjusted median overall survival (OS) was longer for patients with stomach GIST (10.3 years) as compared to small intestine GIST (9.4 years) (P = 0.01). After controlling for patient and tumor-related factors, however, OS did not differ between stomach and small intestine GIST (hazard ratio, 1.19; 95% confidence interval, 0.88 to 1.61; P = 0.26).

CONCLUSIONS

Patients with small intestine GIST more commonly have larger, high mitotic rate tumors, but despite these worse prognostic features, tumor location did not independently impact OS.