Cost-utility of colorectal cancer screening at 40 years old for average-risk patients

The incidence of colorectal cancer (CRC) is increasing in patients under the age of 50. The purpose of this study was to assess the cost-utility of available screening modalities starting at 40 years in the general population compared to standard screening at 50 years old. A decision tree modeling average-risk of CRC in the United States population was constructed for the cost per quality-adjusted life year (QALY) of the five most common and effective CRC screening modalities in average-risk 40-year olds versus deferring screening until 50 years old (standard of care) under a limited societal perspective. All parameters were derived from existing literature. We evaluated the incremental cost-utility ratio of each comparator at a willingness-to-pay threshold of $50,000/QALY and included multivariable probabilistic sensitivity analysis. All screening modalities assessed were more cost-effective with increased QALYs than current standard care (no screening until 50). The most favorable intervention by net monetary benefit was flexible sigmoidoscopy ($3284 per person). Flexible sigmoidoscopy, FOBT, and FIT all dominated the current standard of care. Colonoscopy and FIT-DNA were both cost-effective (respectively, $4777 and $11,532 per QALY). The cost-effective favorability of flexible sigmoidoscopy diminished relative to colonoscopy with increasing willingness-to-pay. Regardless of screening modality, CRC screening at 40 years old is cost-effective with increased QALYs compared to current screening initiation at 50 years old, with flexible sigmoidoscopy most preferred. Consideration should be given for a general recommendation to start screening at age 40 for average risk individuals.