Management of inner ear schwannomas with cochlear involvement in a tertiary referral centre: a retrospective clinical study.

[PURPOSE] A retrospective observational study in a tertiary otologic referral centre was conducted in to analyse a case series of 33 patients with inner ear schwannoma and cochlear involvement (intracochlear, intravestibulocochlear, or transfundal with modiolar involvement) and report the results of different treatment modalities.

[METHODS] We included consecutive patients with inner ear schwannoma and cochlear involvement (intracochlear, intravestibulocochlear, or transfundal with modiolar involvement). Data collectedincluded demographic data, presenting symptoms, audiometric results, radiological characteristics of the tumour at presentation and at follow-up visits, and treatment modalities.

[RESULTS] We included 33 adults with schwannoma; 17 (51%) were men. The mean age at diagnosis was 55 ± 13.1 years. Twenty-four patients (73%) had intracochlear, 5 (15%) transfundal with modiolar involvement, 2 (6%) intravestibulocochlear schwannoma. Two (6%) schwannomas involved the cerebellopontine angle. Concerning symptoms at diagnosis, 28 on 33 patients audiometric datas were available; in these cases, all patients presented some degree of hearing loss. One patient had spontaneous facial paralysis. Twenty-eight (85%) underwent "wait-and-scan" management, during which hearing worsened to AAO-HNS class D for 6 (21%), 15 (54%) showed some degree of tumour growth, 2 (7%) developed spontaneous facial paralysis. All 3 patients with spontaneous facial paralysis had a tumour involving the internal auditory canal. Eleven of 28 patients (39%) underwent surgery after an initial wait-and-scan management (median follow-up of 50 months). Five patients (15%) elected immediate microsurgery tumour removal. Two patients underwent cochlear implantation: one patient did not use the device and had not achieved satisfactory audiometric results The other one exhibited good audiometric results after 3 months (PTA = 30 dB, Speech Discrimination Score = 100% at 70 dB). Complications were rare and minor; no patients showed residual tumour or recurrence.

[CONCLUSIONS] A wait-and-scan policy is the preferred treatment if patients have serviceable hearing. With AAO-HNS class D hearing, microsurgical removal is advised: tumours extending to the internal auditory canal were associated with risk of spontaneous facial paralysis. Surgery is safe and effective. A simultaneous cochlear implant could be proposed.