Advancing Personalized Treatment For Throat Cancer Patients

University of California researchers are studying how to advance personalized treatment for patients with HPV-associated oropharyngeal cancer. The research led by Robert Chin, MD, PhD, a radiation oncologist at UCLA Jonsson Comprehensive Cancer Center, focuses particularly on patients with an inherited variant KRAS gene.

The team of researchers gained data insights and built upon previous studies by reviewing the work of Joanne Weidhaas, MD, PhD, MSM, at UCLA Jonsson Comprehensive Cancer Center. Weidhass discovered that around 16 percent of health and neck cancer patients have the inherited variant KRAS gene.

When these patients received standard chemoradiation treatments for their HPV-positive squamous cell cancers of the oropharynx, physicians witnessed worse toxicity and rates of cancer control. However, researchers suspect these poor patient outcomes could be reversed by pursuing a precision medicine approach with cetuximab.

“In standard clinical practice, tumors are assumed to be different, but patients mostly uniform,” Chin said in a press release.

“Thus, we spent a lot of energy analyzing tumors. However, we have since come to understand that our body’s own immune system is crucial in making treatments effective. Matching the right body to the right treatment may make our treatments less toxic and more effective.”

According to Chin, UCLA researchers are currently conducting a clinical trial. Patients with both the KRAS variant and HPV-positive squamous cell oropharyngeal cancer are randomized into two groups. One group received the standard care treatment while the other received the standard care treatment plus cetuximab.

“We think this approach of identifying unique clusters of patients may be a way for us to design new treatments that are more personalized and effective,” Chin said.

Researchers discovered the KRAS-variant, an inherited genetic mutation found in up to 25 percent of people with cancer, in 2006. The variant has shown its ability to predict a patient’s response to treatment for many different cancers.

Chemotherapy and radiation typically have around a 5-10 percent treatment failure. Additionally, the failure rate is much higher in KRAS-variant patients. However, a short course of cetuximab can help improve the immune systems of those with the KRAS-variant to fight their cancer.

“This and related research at UCLA Jonsson Comprehensive Cancer Center has provided evidence that patients with variant KRAS may have an altered immune system. This likely explains both elevated cancer risk as well as benefit from cetuximab for these individuals,” the press release stated

According to Chin, using these and similar biomarkers could assist in creating personalized radiation therapy and immune therapies for cancer.