Modeled Impact of a Multi-Cancer Diagnostic Aid for Cancer (DAC) Test on Reducing Esophagogastroduodenoscopy (EGD) in US Patients With Dyspepsia

OBJECTIVES: Patients with dyspepsia are at moderate risk of cancer. Clinical guidelines recommend against EGD for patients aged <60 years to rule out cancer. For patients aged >=60 years, EGD is recommended with weak supporting evidence. A large proportion of EGDs performed to evaluate dyspepsia are unnecessary. A blood-based DAC test, aimed to detect the presence or absence of malignancy, could provide reassurance and reduce invasive and costly EGDs. This study aims to estimate the cancer risk of individuals receiving a negative DAC result and the impact of DAC on EGD use among patients with dyspepsia.

METHODS: A mathematical model of a hypothetical cohort of individuals with dyspepsia incorporated DAC test sensitivity (100%, 95% CI 69.2%-100%), specificity (100%, 95% CI 98%-100%), and variability among dyspeptic patients, as well as across all symptoms (sensitivity 66.3%, specificity 98.4%) in the SYMPLIFY study (ISRCTN10226380). Among dyspeptic patients, pre-test cancer risk by age (1.3% ages 40-59, 2.7% ages 40+, 3.7% ages 60+) and EGD use in practice were estimated using the PharMetrics^Ⓡ Plus database. If post-test cancer risk was lower than the corresponding general population risk by age (0.49%, 1.11%, 1.77%), EGD was assumed to be unjustified.

RESULTS: For dyspeptic individuals receiving negative DAC results, the post-test cancer risks were reduced to 0-0.45%, 0-0.93%, and 0-1.26% for the respective age groups and a negative DAC test could reduce EGDs by up to 22%, 25%, and 27% (about 96% of all EGD use in non-cancer patients). Results were sensitive to the assumption of physicians’ decisions to reduce EGD with negative DAC results.

CONCLUSIONS: A non-invasive, highly accurate, diagnostic aid may have the potential to reduce EGDs performed to detect/rule out cancer by up to a quarter among patients with dyspepsia.