Clinical and Budget Impact of Increasing Colorectal Cancer Screening by Blood- and Stool-Based Testing

Screening for colorectal cancer (CRC) is effective at reducing mortality, but nearly 35% of eligible patients do not get screened. New noninvasive screening methods may help increase CRC screening participation. Current CRC screening methods include blood-based screening with methylated Septin 9 (SEPT9) DNA (Epi proColon), stool-based screening with fecal immunochemical testing (FIT), and the multianalyte fecal test combining FIT and stool DNA (Cologuard).

To estimate the cost and clinical implications to health plans, including the clinical and fiscal implications of the use of blood-based screening with SEPT9 DNA, FIT, and FIT/stool DNA, for patients who are unwilling or unable to undergo other recommended screening methods, and to quantify the clinical and fiscal impacts on health plans of expanding CRC screening participation from today's level of 65% up to 80%.

We designed a simulation model to estimate the 3-year clinical and economic impacts for noninvasive screening scenarios and for no screening in the screening-nonadherent population. Clinical inputs were derived from SEPT9, FIT, and FIT/stool DNA validation studies in the peer-reviewed literature, the US census, and other sources in the peer-reviewed literature. We modeled a population of 1 million covered lives (aged 0-64 years) in a hypothetical health plan to estimate CRC, advanced adenoma, and nonadvanced adenoma diagnoses for different screening scenarios. We also modeled the expenditures related to screening, diagnostic follow-up, and treatment costs for CRC for a 15% increase (34,800 members) to 80% screening over the course of 3 years.

In the health plan population, 232,000 members aged 50 to 64 years were eligible for screening, of whom 81,200 (35%) were unscreened. The number of cases of CRC that were detected was similar for each screening scenario, including 221 for SEPT9, 216 for FIT, and 193 for FIT/stool DNA versus 49 for no screening. The 3-year per-member per-month (PMPM) cost impact for screening versus no screening and the evaluation of positive tests for the scenarios was $0.67 for SEPT9, $0.33 for FIT, and $0.69 for FIT/stool DNA. Including the treatment costs for CRC, the PMPM costs increased to $1.08, $0.71, and $0.98, respectively.

Our simulation model suggests that similar clinical detection rates are achievable with the 3 noninvasive blood- and stool-based screening methods. These results support a role for blood- and stool-based screening to increase participation in CRC screening.