A less intense treatment for human papillomavirus positive (HPV+) throat cancer-using robotic surgery followed by low-dose radiation-could provide as much benefit as standard higher-dose radiation and chemotherapy while preserving a patient's throat function, and with potentially less toxicities, according to researchers at UPMC Hillman Cancer Center and Yale Cancer Center.
The results of their randomized phase II clinical trial were presented virtually at the 2020 ASCO Annual Meeting during the Head and Neck Oral Abstract Session (Abstract 6500).
"These results present a promising deintensification approach that has proven to be safe in patients with intermediate risk, locally advanced oropharynx cancer," said Robert Ferris, MD, PhD, Director of the UPMC Hillman Cancer Center and a surgical oncologist specializing in head and neck cancer, who was lead investigator of the trial. The results are not yet published in a peer-reviewed journal.
Treatment Options
About 60 percent of oropharynx cancer, in which cancer cells form in the back of the throat, base of the tongue and tonsils, is associated with HPV infection. The incidence has been increasing in recent years, especially in individuals under the age of 45.
Following robotic surgery, patients with HPV-associated throat cancer would typically undergo high-dose radiation and chemotherapy. While robotic surgery allows for more precise and optimal preservation of the organs and surrounding tissue, there is still concern with the toxicities from the chemotherapy and consequences of tissue damage from radiation therapy, particularly in a younger population.
"Most throat cancers caused by HPV have good outcomes, and the cancer doesn't return or spread to other parts of the body after treatment," said Ferris, who also is Professor in the Departments of Otolaryngology, of Immunology, and of Radiation Oncology at the University of Pittsburgh School of Medicine.
"In this trial, we studied the pathologic features of the tumors obtained at surgery to determine patients' risk of recurrence-low, intermediate or high-to then administer the right amount of postoperative treatment for each risk group."
Patients at low risk were observed. Patients at intermediate risk were randomized to two arms of radiation alone, at standard or lower doses of radiation. Patients at high risk were assigned to usual high-dose radiation therapy plus chemotherapy.
For patients at low and intermediate risk, the 2-year, progression-free survival rate was approximately 95 percent, and reducing radiation or chemotherapy intensity did not increase the risk of recurrence.
"The tissue samples and imaging studies collected in the course of this trial are a rich resource for studying the biology of intermediate- and high-risk disease, in work that is ongoing," said ECOG-ACRIN Head and Neck Committee Chair Barbara Burtness, MD, Professor of Medicine, and co-leader, Developmental Therapeutics Program at Yale Cancer Center and Yale School of Medicine.
Top 10 Best Hospitals for Cancer