Nov. 20, 2020
Radiation therapy is correlated with a host of significant side effects for patients with oropharyngeal cancer. More than 33% of these patients experience grade 3 or greater toxicity following mucosal radiation delivered postoperatively. Toxicities may include dry mouth, throat pain, swallowing difficulty and taste changes, which can lead to emergency room visits, hospitalization and significantly decreased quality of life.
The changing oropharyngeal cancer landscape and its impact
The problem with these complications magnifies when the patient has many decades of life yet to live. As oropharyngeal cancer shifts from a cancer of older people, prompted by tobacco use, to an HPV-related cancer of younger people, radiation oncologists are focusing more than ever on making the therapy less painful and less detrimental to quality of life.
"The chronic side effect burden can impact you not only physically but also psychosocially," says Samir H. Patel, M.D., a radiation oncologist at Mayo Clinic's campus in Phoenix/Scottsdale, Arizona. "The severity is such that head and neck cancer treatment can lead to significant psychosocial burden leading to depression and even suicide in some patients."
The study and its findings
Proton beam therapy made a profound difference for study participants
Mucosal sparing radiation after transoral surgery: protons compared with intensity-modulated radiation therapy (IMRT).
One-year data from a new Mayo Clinic study led by Dr. Patel and colleagues presented at the American Society for Radiation Oncology (ASTRO) Annual Meeting 2020 and also published in the International Journal of Radiation Oncology-Biology-Physics in 2020 reveal that compared with standard therapy ― intensity-modulated radiation therapy (IMRT) ― proton beam therapy (PBT) is better tolerated by patients who've had expert transoral surgical resection of oropharyngeal cancer.
Quality-of-life scores, modified barium swallowing impairment profiles and toxicity rates were unchanged from baseline or even better than baseline measurements. With two undesirable treatment side effects in particular — mucositis and taste changes — patients receiving PBT experienced a profound difference compared with participants receiving IMRT.
"Taste changes really are underrecognized," says Dr. Patel. "It's important because without taste, or if your food tastes terrible or causes nausea, you really can't enjoy any of your food, which is a problem because much of our socializing revolves around food."
Dr. Patel and colleagues conducted the study as a prospective, observational trial including 64 patients accrued from 2016 to 2019 at multiple Mayo Clinic campuses. All patients had American Joint Committee on Cancer seventh edition stage III to IVA cancers and had transoral surgical resection with negative margins with neck dissection. Pathologic nodal findings for all participants indicated adjuvant radiation therapy, which was delivered to the neck only. Patients whose insurance denied PBT were treated with IMRT. Investigators measured toxicities, modified barium swallowing impairment and quality of life via European Organisation for Research and Treatment of Cancer QLQ-H&N35 35 survey before radiation therapy and again at three and 12 months postoperatively.
Of the 61 evaluable patients, 92.1% of whom were male, 76.2% underwent PBT. During the treatment period, six patients experienced grade 3 adverse events, including dermatitis and nausea, yet patients reported no adverse events at this level at three months following PBT and thereafter. With the exception of dry mouth, patients described quality-of-life advantages in swallowing, sense, speech, pain, contact and mouth opening. Those participants who'd received PBT indicated notable improvement in eating, swallowing, feeding tube use and weight loss compared with participants receiving IMRT. Speech and diet normalcy improved markedly over time post-treatment.
Outdoorsman experiences minimized effects of PBT adjuvant therapy
Patient skiing one day after proton beam therapy.
Dr. Patel recounts that one study participant, a 45-year-old avid mountain biker and skier living with oropharyngeal cancer, received proton beam therapy on a Friday, right before a scheduled weekend family ski trip to Telluride, Colorado. Post-therapy, the patient left for the mountains for his winter vacation. He then delighted Dr. Patel by sending a photo of himself that weekend on a 4-foot (1.2 meter) ski jump, putting his recovery post-treatment at distinct contrast to that of patients who received IMRT, which typically requires rest for a few days with opioid therapy.
For more information
Patel SH, et al. A prospective study of mucosal sparing proton beam therapy in resected oropharyngeal cancer patients: Toxicity, quality of life and swallow function. International Journal of Radiation Oncology-Biology-Physics. 2020;108:S161.