Dr. Keiichiro Okano

Abstract:

Historically, advanced head and neck cancer was treated primarily with radical surgery. However, radiotherapy and concurrent chemoradiotherapy, particularly cisplatin-based regimens, have become the preferred approach due to their efficacy in tumor control while preserving normal tissue function. Despite these advantages, radiotherapy induces significant adverse effects, including oral mucositis, xerostomia, salivary gland dysfunction, neuropathies, dysphagia, and dysphonia, which impair quality of life(1). Preclinical and clinical studies have demonstrated the ability of antioxidants to mitigate radiation-induced damage to normal tissues. However, their potential to attenuate the tumoricidal effects of radiotherapy remains controversial. Clinical evidence suggests that systemic antioxidant administration may negatively impact oncological outcomes, reducing tumor control and survival rates(2). Consequently, non-selective antioxidant therapy is generally discouraged in this setting. Recent advances in oxidative stress quantification, such as measuring derivatives of reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP), have improved our ability to assess oxidative balance in cancer patients(3). These developments may offer personalized strategies for antioxidant use.Future research should focus on developing tissue-selective antioxidants that protect normal structures without interfering with ROS-mediated tumor suppression. Large-scale randomized controlled trials (RCTs) will be necessary to validate tailored approaches that optimize therapeutic efficacy while minimizing normal tissue toxicity.