SY5-3 - Role of radiotherapy for multidisciplinary treatment of head and neck cancer

Abstract

Definitive radiotherapy (RT) plays an essential role for locally advanced head and neck cancer (LAHNC), especially for organ preservation. Although RT can show clear benefit in minimal invasive therapy regarding both organ preservation and better patient's QOL, the tumor control of LAHNC was insufficient. Thus, multidisciplinary approach was required in improving efficacy of definitive RT. Concurrent chemoradiotherapy (CCRT) with platinum agents was believed as standard modality because of improving tumor control, while increasing radiation morbidity sometimes became significant problems. Even if CCRT was administered, local failure still remained essential problem for LAHNC after CCRT, thus, surgical intervention was sometimes needed to salvage either residual or recurrent disease. In addition, postoperative CCRT was reported to be considered for patients with high risk features such as positive surgical margin and/or extranodal extension. More intensive treatment sometimes sacrificed functional and social status of LAHNC patients, so less invasive treatment became one of the major clinical requirement for improving treatment outcome. Recently, intensity modulated radiation therapy (IMRT) has been penetrated to Japanese clinical practice for LAHNC. Using this technique, conformal dose distribution to both tumor and microscopic tumor burden could be achieved with sufficient dose-sparing to the normal tissue. Thus, IMRT could allow to minimize late radiation morbidity, especially for xerostomia without sacrificing treatment efficacy. IMRT is believed to useful modality for LAHNC at both definitive and adjuvant setting. More sophisticated IMRT technique would be expected to reduce dose exposure to the normal organ. Furthermore, intensity modulated proton beam therapy could reach to the further improvement of treatment quality with its physical superiority in dose distribution. Prospective trial using these high-precision RT techniques will be warranted.