PP317 - Risk Factors for Ototoxicity in Head and Neck Cancer: A Retrospective Medical Record Review

Abstract:
This study investigates risk factors associated with ototoxicity in head and neck cancer patients treated with chemotherapy/radiation therapy. A retrospective medical record review of patients enrolled in an ototoxicity monitoring program between 2016 and 2021 was conducted. Data collected include patient demographics, history of tobacco and alcohol use, patient comorbidities, tumor characteristics, treatment regimens, and audiological evaluations. Statistical analyses aim to identify potential risk factors associated with ototoxicity incidence. Findings will inform clinicians on risk factors associated with ototoxicity and support the development of personalized strategies for early detection and intervention to improve overall quality of life.

Summary:
Rationale
Ototoxicity refers to inner ear damage caused by treatments with an ototoxic drug. Cisplatin is an antineoplastic drug that is effectively used in head and neck cancer (HNC) therapies and is well-known for its potential ototoxic effect (Paken et al., 2022; Shankar et al., 2024). Approximately 500,000 individuals are diagnosed globally with head and neck cancers every year. These patients necessitate concurrent chemotherapy and radiation therapy which place them at a higher risk for ototoxicity due to the proximity of the tumor to auditory structures (Santucci et al., 2021; Schuette et al., 2020). Currently, treatment advancements have improved the survival rates for HNC patients, hence managing the long-term side effects like ototoxicity becomes increasingly important for maintaining patients’ quality of life. The main purpose of this study is to identify the demographic and clinical risk factors associated with ototoxicity threshold shift in HNC patients receiving chemotherapy/radiation.

Methods
In 2016, a multidisciplinary ototoxicity monitoring program was initiated at Novant Health Forsyth Medical Center for HNC patients receiving chemotherapy/radiation therapy. Audiometric evaluations included otoscopy, pure-tone audiometry (250-8000 Hz), high-frequency audiometry (9000-20,000 Hz), bone conduction thresholds (500-4000 Hz), speech reception and discrimination testing, distortion product otoacoustic emissions (DPOAEs), and tympanometry. Serial assessments included pre-treatment, mid-treatment, post-treatment, six, and 12 months.

Study Design
This single-institution retrospective medical records review of adults with HNC who underwent chemotherapy/radiation therapy between 2016 and 2021. Patients included must have completed a baseline audiological evaluation and at least one follow-up. Data collected include Patient demographics (age, sex, and ethnicity), patient comorbidities (renal disorders, hypertension, DM, tobacco and alcohol use), tumor characteristics (tumor stage, tumor histologic characteristics, and primary tumor site), treatment regimen (concomitant cranial radiation, and radiotherapy dose), and cisplatin dose (single dose volume, final cumulative dose, duration of exposure, total number of doses). Ototoxicity is defined using the ASHA (1994) criteria: a ≥20 dB shift at one frequency, a ≥10 dB shift at two consecutive frequencies, or "no response" at three consecutive frequencies. Audiometric data will be analyzed to assess the severity of hearing loss utilizing the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) scale. The scale assigns numeric ototoxicity grades to quantify the hearing impairment level (Isaradisaikul & Chowsilpa, 2020).

Results
Data collection is ongoing and expected to be completed by February 3, 2025. Descriptive statistics will summarize patient demographics, clinical features, and treatment details. Statistical analyses will explore the incidence of ototoxicity and its correlation with tumor characteristics, treatment regimens, and patient comorbidities.

Conclusion
This study aims to improve understanding of the risk factors contributing to ototoxicity in HNC patients. By identifying these factors, clinicians can better recognize patients at a high risk for significant hearing threshold shifts. This will help guide informational counseling and enable the implementation of personalized strategies for early detection and management of hearing loss. Ultimately, these efforts will enhance the quality of life for cancer survivors by addressing hearing-related issues before they become more severe.