Colorectal cancer screening guidelines recommend screening schedules for each single type of test except for concurrent sigmoidoscopy and fecal occult blood test.
Dr Tuan Dinh and colleagues from California, USA investigated the cost-effectiveness of a hybrid screening strategy that was based on a fecal immunological test and colonoscopy.
The researchers conducted a cost-effectiveness analysis by using the Archimedes Model to evaluate the effects of different colorectal cancer screening strategies on health outcomes and costs related to colorectal cancer in a population that represents members of Kaiser Permanente Northern California.
|A single colonoscopy when patents were 66 years old reduced colorectal cancer incidence by 72%|
|Clinical Gastroenterology and Hepatology|
The Archimedes Model is a large-scale simulation of human physiology, diseases, interventions, and health care systems.
The colorectal cancer submodel in the Archimedes Model was derived from public databases, published epidemiologic studies, and clinical trials.
The research team found that a hybrid screening strategy led to substantial reductions in colorectal cancer incidence and mortality, gains in quality-adjusted life years, and reductions in costs, comparable with those of the best single-test strategies.
The doctors used screening by annual fecal immunological test of patients 50–65 years old, and then a single colonoscopy when they were 66 years old reduced colorectal cancer incidence by 72%.
The patients gained 110 quality-adjusted life years for every 1000 people during a period of 30 years, compared with no screening.
Compared with annual fecal immunological test, FIT/COLOx1 gained 1400 quality-adjusted life years per 100,000 persons at an incremental cost of $9700 per quality-adjusted life years gained and required 55% fewer fecal immunological test.
Compared with fecal immunological test/COLOx1, colonoscopy at 10-year intervals gained 500 quality-adjusted life years per 100,000 at an incremental cost of $35,100 per quality-adjusted life years gained but required 37% more colonoscopies.
The team observed that over the ranges of parameters examined, the cost-effectiveness of hybrid screening strategies was slightly more sensitive to the adherence rate with colonoscopy than the adherence rate with yearly fecal immunological test.
Uncertainties associated with estimates of FIT performance within a program setting and sensitivities for flat and right-sided lesions are expected to have significant impacts on the cost-effectiveness results.
Dr Dinh's team concludes, "In our simulation model, a strategy of annual or biennial fecal immunological test, beginning when patients are 50 years old, with a single colonoscopy when they are 66 years old, delivers clinical and economic outcomes similar to those of colorectal cancer screening by single-modality strategies, with a favorable impact on resources demand."