Non-invasive blood test helps rule out oesophageal cancer

Perth-based medtech company Proteomics International has announced the development and launch of PromarkerEso — a serum glycoprotein biomarker-based diagnostic test for ruling out oesophageal adenocarcinoma (OAC), the predominant form of oesophageal cancer. Designed and developed in Australia, the blood test is designed to offer a quick, non-invasive alternative to endoscopy for people with chronic reflux.

The five-year survival rate for OAC is less than 20%, with median survival time less than one year, as the disease is often asymptomatic in its early stages and is thus frequently diagnosed too late for effective treatment. It is commonly caused by chronic acid reflux — also known as gastro-oesophageal reflux disease, or GORD.

Individuals living with GORD are commonly referred to a gastroenterology specialist for routine endoscopies to assess their risk of OAC in the presence of Barrett’s oesophagus (BE) — a well-known precancerous condition of OAC. This invasive and uncomfortable procedure, often repeated at annual or biannual intervals, requires a fasting prep the night before, a day off work, and assisted transport home from the hospital or clinic due to the use of anaesthesia.

Furthermore, such routine endoscopic surveillance has been called into question with the publication of the BOSS Trial results in Gastroenterology, as the study authors reported no difference in outcomes between biannual surveillance endoscopy and endoscopy at-need only. The need for a better diagnostic tool thus opens up a significant opportunity for PromarkerEso, which simply requires a standard and quick visit to a local blood collection centre.

Proteomics International’s own study, published in Diseases of the Esophagus, analysed 350 people across two independent cohorts. Cohort A compared 89 healthy controls with OAC samples of known stage, while cohort B compared 40 negative controls with unstaged EAC and BE samples. According to the company, PromarkerEso exhibited excellent diagnostic accuracy for all stages of OAC with a minimum area under the curve (AUC) of 0.97. The test also exhibited high sensitivity for OAC in all stages (from 81% for stage I to 100% for stage IV) and also for Barrett’s oesophagus with high-grade dysplasia (BE-HGD; 93%).

“These new results have enormous significance, because if OAC can be detected early it can be more readily treated, whereas late-stage EAC has a very poor prognosis,” said Proteomics International Managing Director Dr Richard Lipscombe. “With the increasing numbers of people living with chronic acid reflux, PromarkerEso has the potential to revolutionise how doctors manage the risk of oesophageal cancer.”

With PromarkerEso now available across Australia, people living with GORD have a quick, non-invasive alternative to endoscopy. Clinical validation of the test demonstrates a negative predictive value (NPV) of 99.99% based on the estimated prevalence of OAC, supporting physicians’ ability to rule out OAC and to confidently manage their patient’s GORD. The high accuracy of the test (91.4% sensitivity, 98.9% specificity) meanwhile gives clinicians critical knowledge to conduct follow-up investigations under endoscopy to better identify the presence of OAC.

“This blood test reduces reliance on costly multidisciplinary and invasive procedures, offers better accuracy, and improves patient experience,” Lipscombe said. The test is now available across Australia to patients through a telehealth consultation via www.myTEST.health, and by physician referral.

Image credit: iStock.com/Pawel Kacperek