In a small but rigorous pilot study, a team led by gastroenterologist Stephen Meltzer demonstrated that a minimally invasive biomarker-based strategy they developed was 90% successful in detecting the most common form of esophagus cancer.
The team’s case-control study, published in Gastroenterology, combined a biomarker panel that predicts esophageal squamous cell carcinoma with a small sponge designed to collect cell samples from people at risk of developing the disease.
Cancer of the esophagus is the seventh most common cancer and the sixth most lethal form of the disease in the world, claiming 544,000 lives in 2020. While relatively rare in the United States, the disease is more common in stretches of Asia, as well as in southern and eastern Africa. Early detection is key to survival, but by the time symptoms — such as trouble swallowing, weight loss, anemia or bleeding — become apparent, the cancer is often too advanced to cure. The five-year survival rate is less than 20%.
During the screening test, the patient swallows the sponge, which is compressed inside a capsule that has a string attached to it. After the capsule has made its way to the bottom of the esophagus, its coating dissolves, allowing the sponge to expand to roughly the size of a nickel with the string still attached. A clinician gently pulls the string until the sponge emerges from the patient’s mouth. The sample, rich with cells from the entire length and circumference of the esophagus, is sealed in a tube and sent to be tested against the specific DNA-based biomarker panel.
Meltzer says the test could bring efficient, inexpensive and noninvasive screening to areas of the world where access to health care is scarce.
“With esophageal cancer, diagnosis is a matter of life and death,” he says. “There are tests to detect Barrett’s esophagus and esophageal carcinoma. But currently, there is no inexpensive, minimally invasive screening tool that can be used regularly to diagnose people who are specifically at risk for esophageal squamous cell carcinoma.”