Radiat Oncol J.  2024 Sep;42(3):192-199. 10.3857/roj.2024.00164.

Unilateral radiotherapy for tonsillar cancer with multiple ipsilateral neck lymph nodes

• Kim TH
• Wu HG
• Ahn SH
• Jeong WJ
• Cha W
• Eom KY

• KMID: 2559533
• DOI: http://doi.org/10.3857/roj.2024.00164

Abstract

Purpose
For tonsillar cancer with multiple ipsilateral neck lymph nodes, the safety and efficacy of unilateral radiotherapy (RT) have long been a topic of debate. We performed retrospective analyses of patients having ipsilateral neck lymph nodes treated with unilateral RT in two tertiary referral hospitals. Material and Methods: This study accrued 29 patients who were diagnosed as well-lateralized tonsillar cancer with multiple ipsilateral neck lymph nodes and underwent unilateral RT from March 2000 to March 2020. Patients underwent treatment with one of the following options or a combination of them: induction chemotherapy, surgery, RT, and concurrent chemoradiotherapy. We analyzed the recurrence pattern and survival with special attention to contralateral neck failure. Also, treatment-related toxicities were compared with a 1:1 matched cohort of those who received bilateral RT, using propensity score matching analysis.
Results
At a median follow-up of 68 months, no contralateral neck failure was observed. Five-year actuarial locoregional recurrence-free survival, distant metastasis-free survival, and overall survival were 85.6%, 91.8%, and 92.7%, respectively. Both the acute and chronic grade 2 xerostomia occurred in 10.3% of the patients. When the toxicity for unilateral RT was compared to that of bilateral RT using a propensity score-matched cohort, a significantly lower rate of acute xerostomia was observed in unilateral RT group (55.1% vs. 82.7%, p=0.002), primarily at grade 2 level (10.3% vs. 51.7%, respectively)
Conclusion
The results of our study suggest that unilateral RT can be safely performed in well-lateralized tonsillar cancer patients with multiple ipsilateral neck lymph nodes.

Keyword

Unilateral radiotherapy; Tonsillar cancer; Multiple ipsilateral lymph nodes; Contralateral neck recurrence; Toxicity; Propensity score matching analysis