DNA-Based Blood Test Could Help Guide Throat Cancer Treatment

People battling throat cancer may gain extra guidance on their treatment with DNA blood tests taken before and after tumor-removing surgery, a new study shows.

In a new trial involving 104 patients, circulating tumor DNA (ctDNA) testing helped doctors make decisions about the need for further treatment, researchers said.

The patients had throat cancer linked with the human papilloma virus (HPV), which causes most (90%) of these tumors.

“While this type of cancer responds well to treatment, patient quality of life is impacted by radiation and chemotherapy,” explained Dr. Catherine Haring, an otolaryngologist specializing in head and neck cancers at Ohio State University in Columbus.

She said ctDNA test results “could help us better tailor treatment to reduce unnecessary side effects while ensuring patients receive the therapy they need.”

More than 22,000 Americans receive a throat cancer diagnosis each year, with men more prone to the disease than women, according to the U.S. Centers for Disease Control and Prevention (CDC).

Decisions around the need for chemotherapy or radiation therapies are especially important, since either can leave patients with long-term side effects that include difficulty swallowing, dry mouth, changes in taste, sleep apnea and underactive thyroid.

In the new study, patients with HPV-linked throat cancers underwent surgery between mid-2021 and early 2025. Most had early stage throat cancers located near their tonsils.

The decision to follow with radiation and/or chemotherapy after the surgery was based on certain risk factors, including results of ctDNA testing. All of the patients gotten the blood test before they underwent surgery, and 74 got the test once more after their operations.

Test results will likely be used in combination with other factors to help physicians decide a patient’s odds for tumor recurrence and their need for post-surgical treatment, Haring said.

Levels of circulating tumor DNA in blood “are influenced by tumor biology and kidney function,” she explained in a university news release.

“Postoperative ctDNA reflects both residual cancer and baseline tumor DNA levels,” Haring said. “This means the test needs to be interpreted in context. A positive result after surgery may indicate higher risk [for tumor recurrence], but a negative result does not always mean a patient is in the clear.”

The researchers plan further study to help boost the sensitivity of the ctDNA test and see how combining it with other risk factors might guide throat cancer care.