Don't Take the Bait, Radiate: Importance of Adjuvant Radiation Therapy for Oral Tongue Cancer

Abstract

This young patient with a lack of traditional risk factors for oral cavity cancer (OCC) presents with a pathologic T2N1 stage III squamous cell carcinoma (SCC) of the tongue.1Hara JHL Juloori A Node out, about it? Consideration of adjuvant treatment of oral tongue cancer.Int J Radiat Oncol Biol Phys. 2022; 112: 849Google Scholar Given the patient's young age, the omission of adjuvant radiation therapy may seem compelling. However, she has 2 indications for adjuvant radiation therapy: a depth of invasion of ≥5 mm and a positive node. Although omission of adjuvant therapy could be considered for a similar stage low risk oropharynx SCC, OCC carries a worse prognosis. Furthermore, ipsilateral level IB, a potential first-echelon drainage site, was not dissected and may harbor microscopic disease. We recommend postoperative radiation therapy with 60 Gy in 30 fractions to the primary site and ipsilateral levels IA through IV, with undissected regions receiving 54 Gy. We at minimum include contralateral level IB with submandibular gland sparing, a possible first-echelon contralateral drainage site. Primary tumor with several pathologic risk factors, approaching midline, or floor of mouth invasion necessitates comprehensive contralateral neck coverage. Regarding systemic therapy, we favor clinical trial enrollment as this patient lacks the standard indication for concurrent chemotherapy: positive margin or extracapsular extension.2Bernier J Cooper JS Pajak TF et al.Defining risk levels in locally advanced head and neck cancers: A comparative analysis of concurrent postoperative radiation plus chemotherapy trials of the EORTC (#22931) and RTOG (# 9501).Head Neck. 2005; 27: 843-850Google Scholar RTOG 0920 investigated concurrent cetuximab for intermediate-risk postoperative head and neck SCC, as we know concurrent cetuximab improves survival compared with definitive radiation alone in non-OCC head and neck SCC, so we await the full results before implementing off trial.3Bonner JA Harari PM Giralt J et al.Radiotherapy plus cetuximab for locoregionally advanced head and neck cancer: 5-year survival data from a phase 3 randomised trial, and relation between cetuximab-induced rash and survival.Lancet Oncol. 2010; 11 (Erratum in: Lancet Oncol. 2010;11:14): 21-28Google Scholar Neoadjuvant immunotherapy is also being investigated for locally advanced OCC; however, this patient was clinical T1N0 at presentation and would not qualify.4Schoenfeld JD Hanna GJ Jo VY et al.Neoadjuvant nivolumab or nivolumab plus ipilimumab in untreated oral cavity squamous cell carcinoma: A phase 2 open-label randomized clinical trial.JAMA Oncol. 2020; 6: 1563-1570Google Scholar Lastly, it is important to recognize that in young patients without a history of smoking, alcohol use, or premalignant lesions, OCC has a poorly understood biological component. As radiation oncologists, we are appropriately concerned about the long-term effects of radiation therapy; however, the morbidity and mortality of recurrent OCC must not be underestimated.5Tam S Araslanova R Low T et al.Estimating survival after salvage surgery for recurrent oral cavity cancer.JAMA Otolaryngol Head Neck Surg. 2017; 143: 685-690Google Scholar