GIST Rates Rise, With Black Patients Facing Higher Mortality

TOPLINE:

Gastrointestinal stromal tumors (GISTs) have increased in incidence over the past 2 decades, with notable survival disparities among racial and ethnic groups, particularly among Black patients who face higher mortality rates from esophageal and gastric GISTs.

METHODOLOGY:

• A steep increase in GIST incidence was observed from 2000 to 2005, largely due to the reclassification of sarcomas as GISTs. The classification of GISTs has changed over time, with all GISTs now considered malignant instead of benign, likely further increasing the incidence. However, updated data on GIST trends are lacking.
• This study assessed recent trends in GIST incidence and survival outcomes across different racial and ethnic groups using data from the National Cancer Institute’s SEER database, including the SEER-22 and SEER-17 registries.
• Researchers evaluated annual percentage changes and incidences among 23,001 patients from SEER-22 (mean age, 64 years) and median overall and cancer-specific survival rates in 12,109 patients from SEER-17 (mean age, 64 years).
• More than half of the patients in both cohorts were White, 17.8%-19.6% were Black, 11.6%-12.3% were Hispanic, and 9.7%-13.2% were Asian or Pacific Islander.

TAKEAWAY:

• The rates of GISTs increased annually between 2000 and 2019 for all organ sites, except the colon, where it decreased by 0.2% per year. Esophageal GISTs increased by 7.3%, gastric by 5.1%, small intestine by 2.7%, and rectal by 1.9%.
• Black patients had significantly lower median overall survival than other racial groups. For example, the median survival for Black patients with esophageal GISTs was 3.6 years vs 15.3 years for White patients (hazard ratio [HR], 6.4; 95% CI, 2.0-20.3). Similar patterns were seen for gastric GISTs — 9.1 years for Black patients vs 11.8 years for White patients (HR, 1.4). GIST-specific mortality was also higher in Black patients for these two organ sites.
• Additionally, Asian or Pacific Islander patients with esophageal GISTs had lower survival rates, with a median of 8.8 years (HR, 5.6) vs 15.3 years for White patients. Similarly, American Indian or Alaska Native patients with gastric GIST had lower survival rates, with a median of 8.5 years (HR, 1.6) vs 11.8 years for White patients.
• Over the 20-year study period, 5-year relative survival rates improved for most patient groups but remained the lowest among American Indian or Alaska Native patients across various GIST sites.

IN PRACTICE:

“We observed a continued increase in the incidence of GISTs after 2005” with a “substantial increase in the last two decades,” the authors wrote. Therefore, “future research should explore lifestyle-related or environmental factors underlying the unfavorable trends” which “could not fully be explained by coding reclassification and advances in diagnostic technologies,” they further added.

SOURCE:

The study was led by Christian S. Alvarez, PhD, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland. It was published online on August 19, 2024, in JAMA Network Open.