U takes lead to fight oral cancer

Jamie VanGeest

Sue Linder sat in the dentist’s chair staring into the bright light as doctors examined the crevices of her mouth.

Two months ago, Linder of Bloomington had a sore in her mouth that wouldn’t go away. Her dentist referred her to the country’s only oral clinic that studies and treats precancerous mouth lesions. The clinic is a part of the University’s Academic Health Center.

While Linder attempted to proudly speak about her daughter’s job with a newspaper in Fort Worth, Texas, Frank Ondrey, an ear, nose and throat doctor from the Medical School, and Nelson Rhodus, a professor of oral medicine at the University’s School of Dentistry, inspected her mouth.

Linder is participating in a study to test a new drug. The drug treats cells of the mouth so they don’t become cancerous, Rhodus said. Oral cancer is the sixth-most common cancer in the United States.

Half of people with oral cancer die within five years. Oral cancer has a survival rate worse than breast, colon and lung cancers, he said.

Survival rates haven’t improved for oral cancer in the past 30 years, unlike with other cancers. This means there has not been a lot of research on the disease, Rhodus said.

Ninety percent of people aren’t even aware that oral cancer exists, and many health care professionals aren’t either, he said.

In the past, cases of oral cancer have been more prevalent in older people who smoke and drink alcohol more often than most people, Rhodus said.

Now, as many as 20 percent of new oral cancer cases are found in younger people who don’t smoke or drink, he said.

Rhodus said a majority of the clinic’s patients are referred by oral surgeons or ear, nose and throat doctors.

Everyone in the ongoing study is in the precancerous stages of oral cancer, and 30 percent to 35 percent of the patients will develop oral cancer, he said.

“We hope this will stop oral cancer before it starts,” Rhodus said.

This study is the first for a drug that has shown promise in preventing oral cancer in its early stages, he said.

Typically, treatment begins after the cancer has fully developed, he said. Then surgery, radiation or chemotherapy is used to eliminate the cancer.

The clinical trial for the new drug is just one aspect of research at the clinic.

The clinic is the only place in the United States trying to find whether saliva can be used to detect oral cancer, Rhodus said.

“One of the reasons why (oral cancer) is so misdiagnosed is because people don’t know how to test for it, detect it or treat it,” he said.

Rhodus said he hopes someone in a state outside of Minnesota will be able to spit into a test tube, mail their saliva and have it tested at the University’s clinic.

The clinic is also looking at genetics to find whether it is a reliable way of determining if a lesion is cancerous or will become cancerous.

Rhodus is testing for genetic risk factors by analyzing blood, tissue and saliva, which allows him to see an entire profile of the patient’s DNA.

His goal is to see if a patient has a “specific genetic signature” that makes them more susceptible to cancer.

Carcinogens, such as tobacco smoke, will turn on genes that cause oral cancer.

The clinic is also studying whether oral cancer is caused by the human papilloma virus, the virus known to cause cervical cancer and genital warts.

The interdisciplinary aspect of the study is unique; the team at the clinic includes three dentists, three ear, nose and throat doctors and two nurses.

Both dentists and ear, nose and throat doctors treat oral cancer, Rhodus said.

“Together we are setting a lot of new standards for patient care,” Ondrey said.

Rhodus said the clinic wouldn’t be possible without the Dental School because the school provides the clinic space.