Source: www.medscape.com
Author: Alexander M. Castellino, PhD

Another trial has shown that de-escalating therapy does not work in patients with good prognosis human papillomavirus-positive (HPV+) oropharyngeal squamous cell carcinoma or throat cancers.

Results from the De-ESCALaTE HPV study show that using the targeted drug cetuximab with radiotherapy does not improve side effects and, more importantly, has worse survival compared with the standard of care — chemotherapy with cisplatin and radiotherapy.

The finding echoes the results from the US National Cancer Institute’s Radiation Therapy Oncology Group (RTOG) 1016 trial, the top-line results of which were released earlier this year, and details of which were presented this week at the American Society of Radiation Oncology (ASTRO) 2018 meeting.

“Do not change your clinical practice of using cisplatin with radiotherapy in these patients,” cautioned Hisham Mehanna, MBChB, PhD, chair of head and neck surgery at the University of Birmingham, United Kingdom, and lead investigator of the De-ESCALaTe study. He presented the results during a presidential session here at the European Society for Medical Oncology (ESMO) 2018 Congress (abstract LBA9).

“Cetuximab did not cause less toxicity and resulted in worse overall survival and more cancer recurrence than cisplatin. This was a surprise — we thought it would lead to the same survival rates but better toxicity. Patients with throat cancer who are HPV+ should be given cisplatin, and not cetuximab, where possible,” Mehanna said in a statement.

Hope for Fewer Side Effects
Cetuximab with radiation is already approved by the US Food and Drug Administration for use in head and neck cancer, including oropharyngeal cancer, and is an accepted standard of care, especially for patients who cannot tolerate cisplatin.

The hope behind de-escalation of therapy was that this regimen would offer similar efficacy but have fewer side effects than the standard regimen of cisplatin plus radiation.

“The side effects of treatment for patients with head and neck cancers are devastating. They experience loss of speech, loss of taste, and have trouble swallowing,” explained ESMO expert Jean-Pascal Machiels, MD, PhD, head of the department of medical oncology at the Cliniques Universitaires Saint-Luc, Brussels, Belgium.

“With HPV increasing rapidly in the Western world, HPV+ head and neck cancers are typically seen in younger patients who respond well to treatment and live for three to four decades. These patients would like to live without the toxicities associated with treatment,” he added.

“Based on a large study in 2006, many patients have been receiving cetuximab with radiotherapy on the assumption that it was as effective as chemotherapy with radiotherapy and caused fewer side effects,” Mehanna commented. That study showed that for patients with squamous cell carcinoma of the head and neck, treatment with cetuximab and high-dose radiotherapy improved locoregional control and reduced mortality. At the same time, side effects were no worse (N Engl J Med. 2006;354:567-578).

 

OCF NOTE: The foundation’s donors were funders of the RTOG 1016 clinical trial over several years.