Patients with mucosal HNSCC deemed unsuitable for curative-intent CRT achieved a 12-month in-field LRC of 80% with high-dose palliative radiation therapy.
High-dose palliative radiation therapy was found to provide durable local control at 1 year with a low incidence of ongoing toxicities in patients with mucosal head and neck squamous cell carcinoma (HNSCC) who are not suitable for definitive chemoradiotherapy, according to findings from a retrospective, real-world study published in Reports of Practical Oncology and Radiotherapy.1
Results showed that patients (n = 53) fully completed the prescribed radiation therapy regimen at a rate of 92.4%. The median overall survival (OS) was 1.8 years (95% CI, 0.81-2.43) and the 12-month in-field locoregional control rate was 80%. The study authors noted that larger primary tumors (T3 or T4) and more advanced disease (AJCC stage III to IV) were associated with a worse rate of in-field locoregional control.
“There is a lack of expert consensus regarding the ideal palliative radiation therapy for HNSCC, with a wide range of dose and fractionation schedules used, and a paucity of literature on prognostic or predictive clinical variables to assist in patient selection for higher-dose regimens,2,3” Anna Lawless, BMBS, MPH, and her coauthors wrote in the publication. “This paper aims to report the real-world efficacy and tolerability of high-dose palliative-intent radiation therapy in patients with incurable mucosal HNSCC and to identify stratification factors which may improve future selection of patients for this treatment.”
Lawless is a radiation oncologist at North Shore Hospital in St Leonards, Australia, a clinical senior lecturer at Sydney Medical School in Australia, and a complex radiation oncology fellow at the University of Texas MD Anderson Cancer Center in Houston.
The retrospective observational cohort study included patients with HNSCC who received high-dose radiation therapy with palliative intent from 2007 to 2024 at academic centers in Australia.1 High-dose radiation therapy was defined as 50 to 55 Gy in 20 fractions over 4 consecutive weeks. All patients underwent FDG-PET staging and histopathology, as conducted by a dedicated HNSCC pathologist, prior to treatment.
At baseline, the median age in the study population was 75.08 years (IQR, 70.3-85.1); 55% of patients had stage IV disease and 28% had stage III disease. Most patients were male (64.2%), had no pain (51.9%), had stage N2 disease (51.0%), had stage M0 disease (77.4%), and received no systemic therapy (60.3%). Tumor subsites consisted of the hypopharynx (11.3%), larynx (13.2%), lip and oral cavity (11.3%), nasal cavity and paranasal sinuses (11.3%), nasopharynx (1.9%), neck (3.8%), oropharynx p16-positive (24.5%), and oropharynx p16-negative or missing (22.6%).
At a median follow-up of 0.81 years, the 1- and 3-year OS rates in the overall population were 60% (95% CI, 45%-73%) and 34% (95% CI: 19–50%), respectively. The median progression-free survival was 1.44 years for all patients. Being a current smoker was associated with higher rates of in-field locoregional failure compared with ex-smokers (HR, 0.76; 0.17-3.39; P = .72) and non-smokers (HR, 0.16; 95% CI, 0.02-1.41; P = .10).
In terms of safety, grade 3 or higher toxicities were reported at a rate of 28%; no grade 4 or 5 toxicities occurred. Over 90% of patients were toxicity-free at 6 months post-radiation therapy. Acute toxicities included grade 3 mucositis (17%), local pain (6.5%), and dysphagia (4.4%).
“Prospective studies are required to determine the relationship between patient, tumor, and treatment factors that impact locoregional control, which will help to better define which patients in this group might benefit from a more or less intensive treatment approach,” Lawless and her coauthors concluded.
