Upper-Neck vs Whole-Neck Irradiation in Patients With Nasopharyngeal Carcinoma

Elective upper-neck irradiation of the uninvolved neck in patients with N0–N1 nasopharyngeal carcinoma demonstrated non–inferiority to whole-neck irradiation in a phase 3 trial.

In the open-label study, 446 patients with untreated, non-keratinising, non-distant metastatic disease at 3 medical centers in China were randomized in a 1:1 to receive either upper-neck irradiation or whole-neck irradiation between January 22, 2016, and May 23, 2018. Eligible participants had a Karnofsky performance status score of 70 or higher.

Total radiation doses of 70 Gy for the primary tumor volume and the enlarged retropharyngeal nodes, 66 to 70 Gy for the involved cervical lymph nodes, 60 to 62 Gy for the high-risk target volume, and 54 to 56 Gy for the low-risk target volume were administered in 30 to 33 fractions, 5 fractions per week. Patients with stage II–IVA disease were recommended to receive combined intravenous cisplatin-based chemotherapy (either induction chemotherapy followed by concurrent chemoradiotherapy or concurrent chemoradiotherapy alone). The median follow-up was 53 months (IQR 46 to 59).

The 3-year regional relapse-free survival was 97.7% in patients who received upper-neck irradiation, compared to 96.3% those who received whole-neck irradiation (non-inferiority P <.0001).

Acute radiation-related toxic effects were similar between the groups, but late toxicity was lower in the upper-neck irradiation group than in the whole-neck irradiation group: any-grade hypothyroidism 30% vs 39%; neck tissue damage 23% vs 40%; skin toxicity 14% vs 25%; and dysphagia 17% vs 32%. One patient in the whole-neck irradiation group died post-treatment from dermatomyositis, which was deemed unrelated to cancer.

Source:
Tang L, Huang C, Zhang N, et al. Elective upper-neck versus whole-neck irradiation of the uninvolved neck in patients with nasopharyngeal carcinoma: an open-label, non-inferiority, multicentre, randomised phase 3 trial. Lancet Oncol. Published online February 28, 2022. doi:10.1016/S1470-2045(22)00058-4.