Clinical utility of a blood-based protein assay to increase screening of elevated-risk patients for colorectal cancer in the primary care setting

A Randomized Controlled Study on Clinical Adherence to Evidence-Based Guidelines in the Management of Simulated Patients With Barrett's Esophagus and the Clinical Utility of a Tissue Systems Pathology Test: Results From Q-TAB

INTRODUCTION

Barrett's esophagus (BE) is a precursor to esophageal adenocarcinoma. Physicians infrequently adhere to guidelines for managing BE, leading to either reduced detection of dysplasia or inappropriate re-evaluation.

METHODS

We conducted a three-arm randomized controlled trial with 2 intervention arms to determine the impact of a tissue systems pathology (TSP-9) test on the adherence to evidence-based guidelines for simulated patients with BE. Intervention 1 received TSP-9 results, and intervention 2 had the option to order TSP-9 results. We collected data from 259 practicing gastroenterologists and gastrointestinal surgeons who evaluated and made management decisions for 3 types of simulated patients with BE: nondysplastic BE, indefinite for dysplasia, and low-grade dysplasia.

RESULTS

Intervention 1 was significantly more likely to correctly assess risk of progression to high-grade dysplasia/esophageal adenocarcinoma and offer treatment in accordance with US society guidelines compared with the control group (+6.9%, 95% confidence interval +1.4% to +12.3%). There was no significant difference in ordering guideline-recommended endoscopic eradication therapy. However, for cases requiring annual endoscopic surveillance, we found significant improvement in adherence for intervention 1, with a difference-in-difference of +18.5% ( P = 0.019). Intervention 2 ordered the TSP-9 test in 21.9% of their cases. Those who ordered the test performed similarly to intervention 1; those who did not, performed similarly to the control group.

DISCUSSION

The TSP-9 test optimized adherence to clinical guidelines for surveillance and treatment of both patients with BE at high and low risk of disease progression. Use of the TSP-9 test can enable physicians to make risk-aligned management decisions, leading to improved patient health outcomes.

Colorectal cancer is associated with increased circulating lipopolysaccharide, inflammation and hypercoagulability

Gut dysbiosis contributes to the development of a dysfunctional gut barrier, facilitating the translocation of bacteria and inflammagens, and is implicated in colorectal cancer (CRC) pathogenesis. Such 'leaky gut' conditions result in systemic inflammation, of which a hallmark is increased hypercoagulability. Fluorescence antibody confocal microscopy was used to determine circulating levels of lipopolysaccharide (LPS) in control and CRC populations. Here we showed that circulating levels of LPS are significantly elevated in the CRC population. We also showed that markers of inflammation and hypercoagulability are increased in this population. Furthermore, anomalous blood clotting and structural changes in blood components are presented. Importantly, the association between LPS levels, inflammation, and hematological dysfunction was analysed. Statistical regression models were applied to identify markers with strong association with CRC, and to investigate the correlation between markers. A core aim is enhanced biomarker discovery for CRC. We conclude that circulating LPS can promote systemic inflammation and contribute to the development of a pathological coagulation system, with resulting chronic inflammation and an activated coagulation system implicated in tumorigenesis. Blood-based screening tools are an emerging research area of interest for CRC screening. We propose the use of additional (novel) biomarkers to effectively screen for CRC.

Establishing Clinical Utility for Diagnostic Tests Using a Randomized Controlled, Virtual Patient Trial Design

Demonstrating clinical utility for diagnostic tests and securing coverage and reimbursement requires high quality and, ideally, randomized controlled trial (RCT) data. Traditional RCTs are often too costly, slow, and cumbersome for diagnostic firms. Alternative data options are needed. We evaluated four RCTs using virtual patients to demonstrate clinical utility. Each study used a similar pre-post intervention, two round design to facilitate comparison. Representative samples of physicians were recruited and randomized into control and intervention arms. All physicians were asked to care for their virtual patients during two assessment rounds, separated by a multi-week time interval. Between rounds, intervention physicians reviewed educational materials on the diagnostic test. All physician responses were scored against evidence-based care criteria. RCTs using virtual patients can demonstrate clinical utility for a variety of diagnostic test types, including: (1) an advanced multi-biomarker blood test, (2) a chromosomal microarray, (3) a proteomic assay analysis, and (4) a multiplex immunofluorescence imaging platform. In two studies, utility was demonstrated for all targeted patient populations, while in the other two studies, utility was only demonstrated for a select sub-segment of the intended patient population. Of these four tests, two received positive coverage decisions from Palmetto, one utilized the study results to support commercial payer adjudications, and the fourth company went out of business. RCTs using virtual patients are a cost-effective approach to demonstrate the presence or absence of clinical utility.