Hearing Loss After Chemo Radiotherapy In Head And Neck Cancer- Is Dose Of Radiation The Only Factor Responsible?

Research Article
Rohit Dominic Jawahar Rebello, Hasib A G, Valentine Almeida., Athiyamaan M S, Venkatram Kini and Firhanaruzin
Cochlea dose; radiotherapy hearing loss

Background; Hearing loss during chemo radiotherapy is a common problem encountered during the treatment of head and neck cancers. In this study, we try to understand the relationship of dose to hearing loss in a subset of patients treated for head and neck malignancies Objectives: To assess hearing loss in patients receiving cisplatin based chemo-radiotherapy for head and neck cancers Methods: Patients were treated with conformal radiotherapy either by 3 dimensional conformal radiotherapy (3DCRT) or intensity modulated radiotherapy (IMRT) with 6 MV photons from a medical linear accelerator. A weekly low dose of cisplatin was given concurrently with radiotherapy. Pure tone audiometry (PTA) was done at baseline and three weeks into radiotherapy as well as at the end of radiotherapy and three months later. The dose received by the cochlea was then correlated with the PTA values. Results: The mean drop in the PTA values of the right ear when compared to base line was 3.77 at 3 weeks, 7.89 at completion of chemo radiation and 10.08 at the third month follow up. However, Pearson test did not show any statistically significant correlation between the dose and the hearing loss. The mean drop in PTA in the left ear was 1.13 at 3 weeks and 6.95 at completion of chemo radiation and 9.32 at the third month follow up. Here too, there was no correlation seen between the dose of radiation received by the cochlea and the hearing loss. Conclusion: There was a drop in the pure tone audiometry values during the course of treatment which was found to b statistically significant in both the ears. However there was no statistically significant correlation between the dose of radiation and hearing loss in this study