Impact of Computer-aided Detection on the Cost-effectiveness of CT Colonography

Purpose: To analyze the cost-effectiveness of adding computer-aided detection (CAD) to a computed tomographic (CT) colonography screening program and to compare it with other options of colorectal cancer (CRC) prevention. Materials and Methods: The cost-effectiveness of screening strategies by using CT colonography with and without CAD, flexible sigmoidoscopy (FS), and optical colonoscopy were compared by using a Markov-based computer model. In the model, a hypothetical population of 100 000 persons aged 50 years underwent colorectal screening every 10 years. Baseline sensitivities for both experienced and inexperienced readers and the incremental accuracy when adding CAD were estimated from a systematic review of the literature. Results: At baseline, the addition of CAD resulted in 9% and 2% increases in CRC prevention rates for inexperienced and experienced readers, respectively, when compared with CT colonography without CAD. Assuming a CAD cost of $50 per CT colonography, the overall program costs increased by only 3%-5%, largely because of the substantial reduction in CRC-related costs. The incremental cost-effectiveness of CT colonography with CAD compared with CT colonography without CAD was $8661 and $61 354 per life-year gained for inexperienced and experienced readers, respectively. Optical colonoscopy was not a cost-effective alternative to CT colonography with CAD performed by experienced readers, with an incremental cost-effectiveness of $498 668 per life-year gained. CT colonography with CAD for inexperienced readers was more clinically effective and cost-effective than FS. At analysis, sensitivity of CT colonography with CAD for polyps 6 mm or larger was the most meaningful variable. Conclusion: The addition of CAD to CT colonography screening improves the CRC prevention rate, resulting in advantageous cost-effectiveness for screening. (C) RSNA, 2009