Bortezomib-Induced Sensorineural Hearing Loss May Be Reversible with Intratympanic Dexamethasone

<b>Background</b>: Bortezomib, a proteasome inhibitor used in multiple myeloma (MM), is associated with several adverse effects, most notably peripheral neuropathy. Ototoxicity, however, remains a rare and underrecognized complication. <b>Case presentation</b>: We report the case of a 74-year-old man with MM who developed sudden unilateral sensorineural hearing loss following subcutaneous bortezomib administration. Audiometry confirmed severe right-sided hearing loss. MRI of the internal auditory canal was normal. Given the absence of other ototoxic agents, bortezomib was identified as the likely causative drug. The patient was treated with intratympanic dexamethasone injections, achieving partial hearing recovery. Subsequent chemotherapy re-exposure triggered another hearing decline, which again improved after repeated intratympanic treatment. <b>Conclusions</b>: Bortezomib-related ototoxicity is a rare but potentially reversible adverse event. This case suggests that early intratympanic corticosteroid therapy may mitigate cochlear injury, allowing continuation of chemotherapy for patients responding well to bortezomib.