Throat cancer study compares treatments for improved swallowing
LONDON, Ontario, Canada: With the rise of the human papillomavirus (HPV) and cases of oropharyngeal cancer doubling since the 1990s, treatment methods are becoming more and more important. In 2012, scientists at Lawson Health Research Institute launched the world’s first clinical trial comparing transoral robotic surgery (TORS) with radiation therapy for the treatment of oropharyngeal cancer. The results have challenged the commonly held belief that TORS leads to better swallowing outcomes.
HPV and oropharyngeal cancer can be a life-changing experience, resulting in many oral health issues, such as the inability to swallow properly, chronic pain of the gingivae and teeth, and dry mouth caused by antibiotics.
According to the researchers, since TORS became an available therapy, it has been the preferred method of treating throat cancer. “Early studies suggested TORS might reduce the risk of swallowing problems historically associated with radiation and it therefore rose quickly in popularity,” explained Dr. Anthony Nichols, associate scientist at Lawson and associate professor with the Department of Otolaryngology—Head and Neck Surgery at the London Health Sciences Centre (LHSC). “But there was no randomized trial to compare patients’ swallowing outcomes. As the first center in Canada to offer TORS, we decided to tackle this problem through the ORATOR [oropharynx: radiotherapy vs. transoral robotic surgery] trial.”
The seven-year study involved 68 research participants from six centers from across Canada and Australia, as well as LHSC and the London Regional Cancer Program. Participants were randomized to receive either precision radiation therapy, often combined with chemotherapy, or TORS.
According to the results, the research team found no difference in survival rates between the two groups. However, a mild decline in swallowing function was observed in 40% of the surgery participants, compared with 26% of the radiation participants. All participants were able eat a full diet after treatment, but 16% of the surgery group said they needed to specially prepare their food. One year after treatment, patients in the surgery group were more likely to experience pain, use painkillers, have issues with their teeth, and experience shoulder impairment. However, those participants in the radiation group experienced an increased risk of tinnitus and high-frequency hearing loss when receiving chemotherapy, some needing hearing aids.
“Each therapy has its different potential side effects, but our findings suggest that TORS is not superior to modern radiation,” said Nichols.
Nichols and his team have now launched the ORATOR 2 trial, which will further compare TORS against radiation and chemotherapy. The goal is to reduce the intensity of radiation and chemotherapy to improve quality of life while maintaining survival rates.
The study, titled “A phase II randomized trial for early-stage squamous cell carcinoma of the oropharynx: Radiotherapy versus trans-oral robotic surgery (ORATOR),” was published online on May 26, 2019, in the Journal of Clinical Oncology.