NEARLY 55,000 PEOPLE in the U.S. learn they have cancer of the mouth or throat each year. Treatments for these cancers, called oral cavity and oropharyngeal cancers, can leave lasting changes in the mouth and throat that make detecting cancer recurrence difficult.

“It isn’t always easy [to find a cancer recurrence] because there are a lot of changes” due to treatment, says Elizabeth Franzmann, who specializes in head and neck cancer surgery at Sylvester Comprehensive Cancer Center at the University of Miami Health System. These treatments, including tissue transfers, surgery, chemotherapy and radiation, can change tissue in ways that might look like early signs of cancer.

Franzmann and colleagues set out to develop a quick and convenient test to identify patients who have a high risk of recurrence and may benefit from more frequent visits and scans and earlier biopsies to detect cancer. The researchers analyzed the approach in a study published Aug. 15, 2024, in JAMA Otolaryngology—Head & Neck Surgery that enrolled 172 adults newly diagnosed with oral cavity and oropharyngeal cancers. Participants rinsed and gargled with a saline solution and then provided saliva samples before treatment and three, six, 12 and 18 months after treatment ended. Researchers found that elevation in two biomarkers—a protein called CD44 that is overexpressed in some cancers and total protein levels—were linked to an increased risk of recurrence.

While the samples in the study had to be sent away to the lab for analysis, Franzmann and researchers plan to develop the saliva test so results can be provided in just one doctor’s visit. They hope the test may provide more information so surgeons and oncologists can better decide who needs more frequent scans and when to biopsy suspicious areas.

“If we could bring this to the clinic and have the result right there in a point-of-care fashion, that, I think, is going to be a big help to our patients and their physicians,” Franzmann says