Inappropriate Ordering of Multitarget Stool DNA Tests for Colon Cancer Screening.

BACKGROUND

CRC screening is recommended for adults aged 45-75. Mt-sDNA is indicated for asymptomatic individuals between the ages of 45 and 85, but not for those with rectal bleeding, iron deficiency anemia, adenomatous polyps, previous colonoscopy within 10 years, family history of CRC, positive results from CRC screening tests within the past 6 months, or age less than 45 and greater than 85. We aimed to determine the prevalence of mt-sDNA use when not indicated and factors associated with inappropriate testing.

METHODS

7,345 patients underwent mt-sDNA testing and were randomized using EMERSE. Charts for the first 500 patients were reviewed to determine whether mt-sDNA was ordered appropriately according to the USPSTF criteria. Seven patients were excluded due to having more than one inappropriate ordering for mt-sDNA.

RESULTS

Of 500 patients, 22.2% had an inappropriately ordered mt-sDNA test. The most common reason for inappropriate ordering was having a previous colonoscopy done within the past 10 years. Rates of inappropriate testing significantly varied by race and the specialty of the ordering provider, with internal medicine providers ordering the most mt-sDNA tests. Rates of inappropriate testing did not significantly vary by sex or type of insurance.

DISCUSSION: Our study suggests that providers may not be familiar with guidelines for the indicated use of mtsDNA, leading to inappropriate referrals and increased costs. Patients at increased CRC risk would benefit from a more sensitive procedure such as a colonoscopy. Future studies could understand the motivation to order testing outside approved indications through provider surveys and interviews.