A strategy for de-escalating radiotherapy may improve quality of life (QOL) without compromising locoregional tumor control in patients with HPV-associated oropharyngeal carcinoma (OPC), according to research published in JAMA Oncology.
The researchers noted that several de-escalation strategies for HPV-associated OPC have focused on deintensifying gross disease treatment. With the current study, the researchers tested the feasibility of reducing the radiotherapy dose and target volume to subclinical regions.
The retrospective study included 276 patients with OPC who were undergoing concurrent chemoradiotherapy. Their median age was 61 years (range, 36-87 years), 89.5% of patients were men, and 90.9% were White. The primary disease site was the tonsil for 47.8% of patients, the base of the tongue for 46.0%, and unknown or other for 6.2%.
Most patients (77.2%) received high-dose cisplatin and were able to complete a cumulative dose of 300 mg/m2 (62.3%). The remaining patients received weekly carboplatin plus paclitaxel (7.2%), weekly carboplatin plus fluorouracil (5.1%), weekly cisplatin (2.9%), or other regimens (7.6%).
The prescribed radiotherapy regimen consisted of 30 Gy to the elective and subclinical treatment regions (15 fractions of 2 Gy), followed by a cone down of 40 Gy, for a total of 70 Gy to all sites of gross disease. The high retropharyngeal nodal basins in the node-negative neck and bilateral levels IB and V basins were not treated.
The researchers noted that, for 87 patients (31.5%), indeterminate nodes or areas immediately adjacent to the gross disease were treated with a dose of 50 Gy instead of 30 Gy.
The median follow-up was 26 months. Locoregional occurrence was observed in 8 patients, including 7 who had recurrence in the primary site and/or gross disease in nodes that received a full 70 Gy dose. The remaining patient had persistent gross disease in a previously unidentified node that received 30 Gy.
At 24 months, the locoregional control rate was 97%, the progression-free survival rate was 88%, the metastasis-free survival rate was 95.2%, and the overall survival rate was 95.1%.
During treatment, 17 patients required a feeding tube. The median duration of feeding tube dependence was 5 months.
At 24 months, QOL composite scores had improved or were similar to baseline with regard to pain, social contact, and issues with eating, speech, and swallowing. On the other hand, senses, dry mouth, and cognitive function were worse than at baseline.
“This cohort study found that the evaluated de-escalation strategy for elective regions showed favorable clinical outcomes and QOL profiles,” the researchers wrote. “Long-term follow-up data will help affirm the efficacy of this strategy as a care option for treating HPV-associated OPC with primary CCRT [concurrent chemoradiotherapy].”
Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Tsai CJ, McBride SM, Riaz N, et al. Evaluation of substantial reduction in elective radiotherapy dose and field in patients with human papillomavirus-associated oropharyngeal carcinoma treated with definitive chemoradiotherapy. Published online January 20, 2022. doi:10.1001/jamaoncol.2021.6416