Noninvasive strategies for colorectal cancer screening: opportunities and limitations

In the United States, only 67% of patients are up to date with colorectal cancer (CRC) screening. While colonoscopy is highly sensitive and specific for CRC and precursor lesion detection and removal, it is invasive, expensive and resource heavy. Hence, there is an unfulfilled need for multiple modality CRC screening that can improve current CRC screening rates and may be resource effective strategies when used in conjunction with a colonoscopy program. Our review highlights the complementary, often underutilized, noninvasive CRC screening methods with a focus on performance, risks, benefits, and recent updates.

Studies demonstrate that fecal immunochemical testing (FIT) is superior to guaiac-based fecal occult blood tests for CRC screening. Studies show superiority of multitarget stool DNA test to FIT in sensitivity, though with concern for decreased specificity in setting of one-time tests. Technical advances continue to improve accuracy of colon capsule endoscopy. There are ongoing studies to characterize often difficult-to-detect high-risk lesions in computed tomography colonography. Septin 9 continues to have suboptimal accuracy for CRC screening, but has been shown to be associated with more advanced, invasive CRC stages.

There are ongoing advances in noninvasive screening modalities for CRC; these should be considered as alternatives to colonoscopy in specific patient populations.