Update of epidemiology, survival and initial treatment in patients with gastrointestinal stromal tumour in the USA: a retrospective study based on SEER database.

Objectives: An updated epidemiological analysis of gastrointestinal stromal tumour (GIST), the change of cancer-specific survival (CSS) and patterns of initial treatment are of interest.

Design: A retrospective study using data from the Surveillance, Epidemiology and End Results (SEER) database.

Setting And Participants: A total of 5625 patients with GIST diagnosed between 2010 and 2019 were identified.

Primary Outcome Measures: Age-standardised incidence rate (ASIR) and annual prevalence rate were calculated. SEER combined stage, period CSS rate and initial treatment were summarised. All the data were calculated by SEER*Stat software.

Results: From 2010 to 2019, the ASIR of GIST increased from 0.79 to 1.02 per 100 000 person-years, with an increase of 2.4% annually. The increase was across age and sex subgroups. The prevalence trend was similar with the ASIR trend in each subgroup. The stage distributions were similar between different age groups, but varied among different primary tumour sites. More importantly, a stage shift from regional stage to localized stage at diagnosis was found, which may result in the improvement of CSS over years. Overall, the 5-year CSS rate of GIST was approximately 81.3%. Even for metastatic GIST, the rate exceeded 50%. Surgery was the most common treatment regimen for GIST, followed by surgery and systemic treatment. Whereas approximately 7.0% patients were undertreated, which was more pronounced among patients with distant and unknown stages.

Conclusions: The findings of this study suggest an improving early detection of GIST and an improving ability of accurate staging. Though most patients are effectively treated and perform good survivals, approximate 7.0% patients may be undertreated.