The first study to measure real-world listening challenges and hearing loss progression in cancer survivors over a long period of time has documented significant hearing difficulties in many testicular cancer survivors.
The study tracked 100 testicular cancer survivors with no hearing loss at baseline who received cisplatin-based chemotherapy. The median time since chemotherapy was 14 years.
Comprehensive audiologic assessments revealed that 78% had audiometrically defined hearing loss (HL) and experienced significant difficulties in everyday listening situations. The men were, on average, 48 years old.
The interdisciplinary study, led by researchers at the University of South Florida (USF) and Indiana University, was published in the Journal of the American Medical Association Oncology on 6 June 2024.
The research team found higher doses of cisplatin led to more severe and progressing hearing loss, especially in patients with risk factors such as hypertension and poor cardiovascular health. The men also experienced increased difficulty hearing in common environments such as a loud restaurant.
“Importantly, a significant time-cisplatin dose interaction occurred as patients given 300 mg/m2 or less experienced significantly less progression than those who received more than 300 mg/m2,” researchers said.
Those self-reporting HL had two-fold worse hearing than survivors without self-reported HL. The 54 patients with self-reported HL showed clinically significant functional impairment on Words-in-Noise (WIN) testing.
Poorer WIN performance was also significantly associated with hypercholesterolemia, lower-education, severity of audiometrically defined HL and cisplatin-related hearing loss (CRHL) severity.
Cisplatin-related hearing loss (CRHL) progression was associated with hypercholesterolemia and increasing age.
“Follow-up of cisplatin-treated cancer survivors should include strict hypercholesterolemia control and regular audiological assessments,” the researchers wrote. “Risk stratification through validated instruments should include querying hearing concerns. CRHL progression relative to age-matched norms is likely associated with cumulative cisplatin dose; investigation over longer follow-up is warranted.”
Cisplatin is commonly used in chemotherapy treatments for cancers including bladder, lung, neck and testicular. It is administered intravenously and affects various parts of the body, but researchers said the ears were particularly vulnerable as they had little ability to filter out the drug, causing it to become trapped. This can lead to inflammation and destruction of sensory cells that are critical for coding sound, causing permanent hearing loss that can progressively worsen well after cisplatin treatments are completed.
Chemo patients should have hearing tests
Lead author, Associate Professor Victoria Sanchez from the USF Health Department of Otolaryngology Head & Neck Surgery, said most patients still did not get their hearing tested before, during or after chemotherapy.
“Our study highlights the need for regular auditory evaluations to manage and mitigate long-term hearing damage,” she said.
Co-author, Dr Lois Travis, said it was important to follow the study participants for life.
“Their current median age is only 48 years and eventually they will enter the years at which age-related hearing loss also begins to develop,” said Dr Travis, Lawrence H. Einhorn Professor of Cancer Research at Indiana University School of Medicine and a researcher at the IU Melvin and Bren Simon Comprehensive Cancer Center.
The research is part of The Platinum Study, an ongoing research effort she leads funded by the National Cancer Institute to study cisplatin-treated testicular cancer survivors.
Professor Robert Frisina, chair of the USF Department of Medical Engineering, added: “It’s important that we understand the real-world effects of patients’ sensory problems and if we can understand that, then we can develop better therapeutic strategies and preventive measures to improve the long-term quality of life for cancer survivors.
“This research gives oncologists the information they need to explore alternative treatment plans that could reduce the long-term side effects, such as altering the dosages and timing of the cisplatin in the treatment, when that could be an appropriate option.”
Prof Frisina said innovative solutions, such as Pedmark, a new FDA-approved injection that mitigates cisplatin-induced hearing loss in children and adolescents, represented promising steps forward.
The researchers hope the study will inspire further investigation into alternative chemotherapeutic protocols and preventive measures such as drugs to prevent or reduce hearing loss.
The American Cancer Society says that, in addition to cisplatin, high doses of chemotherapy, especially ones that are platinum-based such as carboplatin, can cause damage to the cochlea and lead to hearing loss.
