“MC1675 is an important and exciting trial,” stated invited discussant Farzan Siddiqui, MD, PhD, of the Henry Ford Cancer Institute, Detroit. “Congratulations to the authors and to Dr. Ma for his award.”

Farzan Siddiqui, MD, PhD

“There is strong evidence to suggest that patients with HPV-positive oropharyngeal cancers have improved outcomes compared to patients with HPV-negative oropharyngeal cancers. These patients are generally younger, have fewer comorbidities, and probably can withstand cancer treatments better than older patients. But the incidence is rising in younger patients, and they will have to live [longer] with the side effects of treatment,” Dr. Siddiqui continued.

With or Without Extranodal Extension

Many approaches have been employed for de-escalation of adjuvant treatment, including lower doses of radiation therapy and alternatives to cisplatin chemotherapy. “For radiation therapy, we are looking at reduced dose and trying to limit radiation therapy to the uninvolved neck nodal region,” explained Dr. Siddiqui. “The study included 115 patients with extranodal extension [60%]. Other trials have not done this,” he noted.

Dr. Siddiqui continued: “Is de-escalation ready for prime time for patients without extranodal extension? The outcomes are inferior for patients with extranodal extension especially in the subgroup with N2 disease.”

What About Transoral Robotic Surgery?

In MC1675, transoral robotic surgery was performed. According to Dr. Siddiqui, this type of surgery should be performed only in highly specialized, high-volume centers with expert pathologic assessment of margins and extranodal extension status. The side effects of transoral robotic surgery and chemotherapy should be kept in mind in these intermediate-risk patients who receive trimodality therapy.

“Transoral robotic surgery followed by low-dose hyperfractionated radiation therapy and concurrent chemotherapy may be feasible in a select group of patients with intermediate-risk HPV-positive oropharyngeal cancers. But for now, de-intensification of therapy should not be done in patients with pathologic extranodal extension and/or N2 disease,” he stated.

At the end of his presentation, Dr. Siddiqui reminded the audience about the importance of HPV vaccination in the prevention of these cancers. 

DISCLOSURE: Dr. Siddiqui has received honoraria and travel reimbursement and serves on an advisory board for Varian Medical Systems.