ESTRO 2024 - Abstract Book

S1395

Clinical - Head & neck

ESTRO 2024

Nasopharyngeal Carcinoma (NPC) presents a unique challenge in oncology, and Intensity-Modulated Radiotherapy (IMRT) stands as a pivotal advancement in its management. IMRT offers precise radiation dosing, preserving the integrity of critical Regions of Interest (ROIs) and improving patients quality of life. This study sought to assess the acute and late side effects of IMRT in NPC patients, as well as radiation doses delivered to Organs at Risk (OARs), within the context of the COVID-19 pandemic, with a primary focus on staging-driven insights.

Material/Methods:

In this retrospective study, we utilized data from the QSUNT national cancer registry, focusing on patients undergoing IMRT for NPC from 2018 to 2021. Our cohort consisted of 37 patients, aged 32 to 79, who received IMRT with or without chemotherapy and presented with no metastases. Patients were categorized into distinct stages as follows: Stage I, 13 patients; stage II, 7 patients; stage III; 13 patients; stage IVA, 4 patients. Total radiation doses between 54 Gy, 60Gy and 69.96 Gy were administered, with strict adherence to OAR dose constraints, and fractionated dosing regimens were examined. To gain a comprehensive understanding of the patient experience, we employed a questionnaire adapted from Michigan's Quality of Life (QoL), Anderson's QoL questionnaires, and CTCAE v5.0 guidelines for Head and Neck Cancers. Out of the 37 patients, 21 responded, providing valuable insights into overall survival (OS), disease-free survival (DFS), and the spectrum of acute and late radiation-related side effects.

Results:

IMRT treatment consistently adhered to prescribed dose limits, with minimal OAR overdosing observed in three cases. Acute side effects were frequently reported, including fatigue (76%), dysphagia (71%), and headache (66%). Other common side effects encompassed radiation dermatitis (66%), xerostomia (66%), and mucositis (57%). Weight loss, primarily of Grade 2 (G2), affected 49% of patients, with one case reporting epilepsy during treatment. Late side effects, including xerostomia (43%), trismus (29%), and rhinorrhea (24%), prevailed. Additional side effects, such as ageusia, anosmia, osteoradionecrosis (ORN), dental caries, and thrombosis, were reported at varying frequencies. Most early side effects fell within the G2-G3 range, with occasional G4 events. Disease recurrence occurred in 33% of patients. Remarkably, one-third of the patients received treatment during the most aggressive phase of the COVID-19 pandemic, potentially influencing outcomes.

Conclusion:

This study brings to light the presence of common early and late side effects in IMRT-treated NPC patients, with persistent xerostomia affecting 43% of cases. The potential impact of the COVID-19 pandemic on treatment outcomes and its influence on patients' abilities to perceive taste and smell alterations cannot be overlooked. Nonetheless, the study demonstrates a relatively high overall survival rate of 76% over a 3 year period, despite disease recurrence in a substantial proportion of cases. These findings underscore the need for ongoing research to optimize treatment strategies for NPC patients undergoing IMRT, especially with due consideration of the patients staging. A special emphasis on tailoring interventions based on disease stage may further enhance the precision and effectiveness of IMRT in addressing this intricate malignancy. Future research avenues could explore the promise of liquid biopsies in predicting and managing treatment response, thereby adding to the armamentarium of strategies for navigating the multifaceted landscape of NPC.