MONDAY, June 30, 2025 (HealthDay News) — The thought of swallowing a pill on a thread isn’t the most pleasant notion, but it could be a vastly better alternative for people at increased risk of throat cancer, a new study says.

For nearly 20 years, U.K. resident Duncan Cook has had regular endoscopies to monitor his case of Barrett’s esophagus, a condition in which acid reflux damages cells and can lead to throat cancer.

Then researchers offered him another option: Swallow a capsule that dissolves in the stomach to release a small sponge.

Using an attached string, health care professionals draw the sponge back up the throat, lightly scraping cells off the esophagus along the way.

“The first time I had the sponge, I was a bit nervous. It’s quite a big pill to swallow, but it’s much better than going for endoscopies,” Cook, 57, a plumbing and heating engineer from Cambridge, said in a news release.

“The sponge test is faster, you don’t need sedation for it, and you don’t need to find someone to come with you to drive you home after,” Cook continued. “I was able to have the test done and go right back to work after.”

About half of all patients with Barrett’s esophagus could use this pill-on-a-string rather than an endoscopy to keep tabs on their condition, researchers concluded in a report published recently in The Lancet.

In Barrett’s esophagus, acid reflux damages throat cells in a way that can transform them into a pre-cancerous state known as dysplasia, researchers said.

“It’s extremely important to monitor patients so that we can catch the dysplasia and prevent it developing to cancer – and if someone is unfortunate enough to develop cancer, we can catch it early and treat it,” senior researcher Rebecca Fitzgerald, director of the Early Cancer Institute at the University of Cambridge, said in a news release.

Cancer of the esophagus is hard to treat, with fewer than 1 in 5 patients surviving for five or more years following diagnosis, researchers said in background notes. The number of people diagnosed with throat cancer has quadrupled since the 1970s.

“But the chances of Barrett’s progressing to cancer are low, and endoscopies are not very pleasant procedures,” Fitzgerald continued. “Added to that, endoscopies are not always a reliable way of spotting early cancers and can depend on the skill of the person doing the endoscopy and the equipment being used.”

“What we need is an alternative surveillance method that’s less invasive, easier to administer and more reliable,” Fitzgerald said.

In endoscopy, patients lie on their side while doctors run a long, thin, camera-equipped tube down their throat. People typically must fast prior to their endoscopy, and are sedated and anesthetized to eliminate their gag reflex, according to the Mayo Clinic.

For this study, researcher recruited 910 patients being monitored for Barrett’s esophagus at 13 U.K. hospitals.

The patients were given the capsule test, and based on their results, were assigned to one of three groups: High, medium or low risk.

Cell samples drawn from the sponge are stained with a chemical and examined under a microscope, looking for two key “red flag” changes that suggest the cells are pre-cancerous, researchers said.

All patients also received an endoscopy, and these test findings were compared with their capsule sponge results.

More than half of the patients (54%) wound up classified as low-risk based on their sponge test results, showing no signs of cellular changes that would increase their risk of cancer, results show.

A follow-up endoscopy revealed that two of these 495 patients — 0.4% — had high-risk cell changes that needed follow-up exams. No cancers were found among the patients judged to be at low risk by the sponge test.

“Our findings suggest that the capsule sponge could help stratify patients with Barrett’s esophagus by risk and that half of them will fall into the low-risk group,” said researcher Peter Sasieni, director of the Cancer Research UK Cancer Prevention Trials Unit at Queen Mary University of London.

“Given that the risk of these individuals progressing to dysplasia and then to esophageal cancer is so low, it should be safe to replace their usual endoscopy with the capsule sponge,” Sasieni added in a news release.

The pill-on-a-string test also is much quicker, easier and cheaper than endoscopy, added lead researcher Dr. Keith Tan, an honorary registrar in gastroenterology and hepatology at Addenbrooke’s Hospital in the U.K.

“The capsule sponge can be administered easily and quickly by nurses with only limited training required and will not need to take up precious endoscopy resources, which may be better for patients and more cost-effective,” Tan said in a news release.

Researchers plan to continue honing the capsule test by improving the lab work that evaluates throat cells scraped up by the sponge. They also are evaluating the potential of AI to help evaluate these tests.

More information

The Mayo Clinic has more on an endoscopy.

SOURCE: University of Cambridge, news release, June 23, 2025