Breaking from the invasive nature of imaging scopes and the Cytosponge, some researchers are looking to use “liquid biopsy” or blood tests to detect abnormalities in the blood like DNA or microRNA (miRNA) to identify precursors or presence of a disease. Much remains to be done to develop a clinically meaningful test, but the use of miRNAs to detect disease is an intriguing option. miRNAs control gene expression, and their dysregulation has been associated with the development of many diseases. One study found that patients with Barrett’s esophagus had increased levels of miRNA-194, 215, and 143 but these findings were not validated in a larger study. Other studies have demonstrated similar findings, but more research must be done to validate these findings in larger cohorts.
Other novel detection therapies have been investigated, including serum adipokine and electronic nose breathing tests. The serum adipokine test looks at the metabolically active adipokines secreted in obese patients and those with metabolic syndrome to see if they could predict the presence of Barrett’s esophagus. Unfortunately, the data appear to be conflicting, but these tests can be used in conjunction with other tools to detect Barrett’s esophagus. Electronic nose breathing tests also work by detecting metabolically active compounds from human and gut bacterial metabolism. One study found that analyzing these volatile compounds could delineate between Barrett’s and non-Barrett’s patients with 82% sensitivity, 80% specificity, and 81% accuracy. Both of these technologies need large prospective studies in primary care to validate their clinical utility.
A discussion of the effectiveness of these screening tools would be incomplete without a discussion of their costs. Currently, endoscopic screening costs are high. Therefore, it is important to reserve these tools for the patients who will benefit the most – in other words, patients with clear risk factors for Barrett’s esophagus. Even the capsule endoscope is quite expensive because of the cost of materials associated with the tool.
Cost-effectivenes calculations surrounding the Cytosponge are particularly complicated. One analysis found the computed incremental cost-effectiveness ratio (ICER) of endoscopy, compared with Cytosponge, to have a range of $107,583-$330,361. The potential benefit that Cytosponge offers comes at an ICER for Cytosponge screening, compared with no screening, that ranges from $26,358 to $33,307. The numbers skyrocket when you consider what society would be willing to pay (up to $50,000 per quality-adjusted life-year gained).