Autoimmune inner ear disease in a melanoma patient treated with pembrolizumab

Immune checkpoint inhibitor-related hearing loss: a systematic review and analysis of individual patient data

PURPOSE

Immune checkpoint inhibitors (ICIs) are related to various immune-related adverse events (irAEs). However, the knowledge is limited with rare irAEs like hearing loss. Therefore, we evaluated the characteristics, presentation, and treatment of ICI-related hearing loss by reviewing the individual patient data from the previous studies.

METHODS

We conducted a systematic search of the Web of Science, PubMed, and Embase databases for studies published until 17 November 2022. The selected MeSH search terms were "hearing loss" OR "hearing impairment" OR "ototoxicity" OR "vestibular toxicity" OR "audiovestibular toxicity" AND "immune checkpoint inhibitor" OR "immunotherapy."

RESULTS

A total of 38 patients were included. Melanoma was the most frequent diagnosis (73.7%). The median time from ICI initiation to hearing loss development was 3 months. The hearing impairment was secondary to bilateral sensorineural hearing loss (SNHL) in 24 (68.6%) patients, and at least one other irAE accompanied the hearing loss in 24 patients. Hearing loss significantly improved in 45.7% of the patients. The overall response rate and disease control rate were 67.6% and 85.3%, respectively.

CONCLUSION

We observed that most cases of ICI-related hearing loss were reversible, observed in patients with melanoma, accompanied by other irAEs, and associated with a high response rate to ICIs. With the expanded use of ICIs in the earlier treatment lines and adjuvant settings, the number of survivors with ICI-related hearing loss is expected to increase. Further research is needed to define the true prevalence of ICI-related hearing loss, optimal diagnosis, and management.

Bilateral cochlear implantation after immunotherapy-related profound hearing loss: A case report

OBJECTIVES

Immune-checkpoint inhibitors (ICI) are being utilized with increasing frequency and may be linked to neurologic and audiovestibular toxicities. This report aimed to describe a case of ICI-induced sensorineural hearing loss ultimately requiring bilateral cochlear implantation.

METHODS

A 42-year-old female with stage IV metastatic melanoma of the perianal skin was treated with ipilimumab (blocker of cytotoxic T-lymphocyte associated protein 4 [CTLA-4]) and nivolumab (anti-programmed cell death protein 1 [PD1]). After 21 weeks of therapy, she developed sudden vertigo and bilateral hearing loss. A full workup including MRI and lumbar puncture ruled out intracranial parenchymal metastases, leptomeningeal metastases, stroke and intracranial infection. ICI-associated aseptic meningoencephalitis was therefore diagnosed. The patient received systemic steroids as well as intratympanic steroids, which temporarily improved hearing, but eventually developed permanent, bilateral profound sensorineural hearing loss.

RESULTS

The patient received bilateral cochlear implants and has demonstrated good performance one year after implantation.

DISCUSSION

ICI are being increasingly used to treat a variety of advanced malignancies. This is the first report of bilateral cochlear implants in the context of profound hearing loss after an immunotherapy induced meningoencephalitis.

CONCLUSION

ICI carries the risk of potential ototoxicity, including profound SNHL as depicted in our case. Cochlear implantation proved to be beneficial and may be considered in patients with ICI-related hearing loss.

Ototoxicity Review: A Growing Number of Non-Platinum-Based Chemo- and Immunotherapies

OBJECTIVE

To raise awareness of the growing list of non-platinum-based chemo- and immunotherapeutic agents that have been associated with ototoxicity and to introduce the possible mechanism of ototoxicity of these agents.

DATA SOURCES

PubMed, Embase, and Web of Science.

REVIEW METHODS

A systematic review was performed following the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-analyses). PubMed, Embase, and Web of Science databases were searched for published reports of ototoxicity from non-platinum-based chemo- and immunotherapeutic agents in adult and pediatric patients. Therapies that utilized any platinum-based agent were excluded.

CONCLUSIONS

Ototoxicity from non-platinum-based chemo- and immunotherapies is an evolving problem. There were 54 reports-39 case reports and 15 cohort studies-documenting ototoxicity from 7 agents/combination therapies. Of these reports, 37 (69%) were published within the last 15 years (after 2005). No recovery of hearing was documented in 21 of 56 cases (38%). Pretreatment audiograms were uncommon (19/54 studies, 35%), despite documented ototoxic associations.

IMPLICATIONS FOR PRACTICE

There is a growing number of novel, ototoxic, non-platinum-based chemo- and immunotherapeutic agents with various potential mechanisms of action. Otolaryngologists will need to prioritize awareness of these agents. This growing list of agents, many of which have reversible effects, suggest a need for standardized ototoxicity monitor protocols so that appropriate and timely management options can be implemented.

Immunotherapy and Modern Radiotherapy Technique for Older Patients with Locally Advanced Head and Neck Cancer: A Proposed Paradigm by the International Geriatric Radiotherapy Group

The standard of care for locally advanced head and neck cancer is concurrent chemoradiation or postoperative irradiation with or without chemotherapy. Surgery may not be an option for older patients (70 years old or above) due to multiple co-morbidities and frailty. Additionally, the standard chemotherapy of cisplatin may not be ideal for those patients due to oto- and nephrotoxicity. Though carboplatin is a reasonable alternative for cisplatin in patients with a pre-existing hearing deficit or renal dysfunction, its efficacy may be inferior to cisplatin for head and neck cancer. In addition, concurrent chemoradiation is frequently associated with grade 3-4 mucositis and hematologic toxicity leading to poor tolerance among older cancer patients. Thus, a new algorithm needs to be developed to provide optimal local control while minimizing toxicity for this vulnerable group of patients. Recently, immunotherapy with check point inhibitors (CPI) has attracted much attention due to the high prevalence of program death-ligand 1 (PD-L1) in head and neck cancer. In patients with recurrent or metastatic head and neck cancer refractory to cisplatin-based chemotherapy, CPI has proven to be superior to conventional chemotherapy for salvage. Those with a high PD-L1 expression defined as 50% or above or a high tumor proportion score (TPS) may have an excellent response to CPI. This selected group of patients may be candidates for CPI combined with modern radiotherapy techniques, such as intensity-modulated image-guided radiotherapy (IM-IGRT), volumetric arc therapy (VMAT) or proton therapy if available, which allow for the sparing of critical structures, such as the salivary glands, oral cavity, cochlea, larynx and pharyngeal muscles, to improve the patients' quality of life. In addition, normal organs that are frequently sensitive to immunotherapy, such as the thyroid and lungs, are spared with modern radiotherapy techniques. In fit or carefully selected frail patients, a hypofractionated schedule may be considered to reduce the need for daily transportation. We propose a protocol combining CPI and modern radiotherapy techniques for older patients with locally advanced head and neck cancer who are not eligible for cisplatin-based chemotherapy and have a high TPS. Prospective studies should be performed to verify this hypothesis.

Uveitis in Tumor Patients Treated with Immunological Checkpoint- and Signal Transduction Pathway-Inhibitors

PURPOSE

New tumor therapies like immune checkpoint inhibitors and small molecule inhibitors of MEK and BRAF have increased the patient's survival rate but can be burdened with severe side-effects including uveitis. Here, we show the spectrum, treatment, and outcome of uveitis types induced by tumor treatment.

METHODS

In this retrospective study, we have included 54 patients from different centers who were developing uveitis under tumor therapy. A 16-item questionnaire was analyzed for type, treatment, and outcome of uveitis and type of tumor treatment, which we have correlated here.

RESULTS

Irrespective of the tumor treatment, most patients developed anterior uveitis. All patients received corticosteroids and some additional immunosuppressive treatments. Cessation of tumor therapy was necessary only in a minority of cases.

CONCLUSIONS

Ocular autoimmunity should be differentiated from toxic effects of cancer treatment and timely recognized since it can be generally well controlled by anti-inflammatory treatment, preserving the patient's vision without cessation of the tumor treatment.

Audiovestibular Toxicity Secondary to Immunotherapy: Case Series and Literature Review

Introduction

Audiovestibular toxicity secondary to immunotherapy has only rarely been reported in the literature. Herein, we examine our experience diagnosing and managing audiovestibular immune-related adverse events (irAEs) in patients undergoing immunotherapy.

Methods

Four patients who experienced irAEs were included. Demographics, immunotherapy regimen, diagnostic tests, treatment, and outcomes were recorded in a retrospective chart review.

Results

The cases of three patients with metastatic melanoma and one patient with metastatic renal cell carcinoma are presented. Hearing loss and tinnitus were the most common presenting symptoms. Immune checkpoint inhibitors (ICIs) were implicated in three cases and T-cell therapy in one case. Two of three patients (67%) treated with steroids had substantial improvements in hearing.

Conclusions

Audiovestibular irAEs are a rare complication of immunotherapy. Suspicion for symptoms including hearing loss, tinnitus, and/or vertigo should prompt an expedient referral to the otolaryngologist for evaluation, as symptoms may improve with corticosteroid use. Hearing and/or vestibular deficits can have a substantial impact on the quality of life for affected patients, but rehabilitation options do exist.

Immune-Related Oral, Otologic, and Ocular Adverse Events

Emerging immunotherapeutic agents, including immune checkpoint inhibitors targeting cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), programmed cell death protein 1 (PD-1), and programmed cell death protein ligand 1 (PD-L1), have revolutionized cancer treatment. The first immune checkpoint inhibitor (ICI) ipilimumab, an anti-CTLA-4, was approved in 2011. Since then, the US Food and Drug Administration (FDA) has approved more than half a dozen immune checkpoint inhibitors to treat various malignancies. These agents are part of a broader class of chemotherapy agents termed immunotherapy, which selectively target different steps in the immune response cascade to upregulate the body's normal response to cancer. While the effects of traditional chemotherapy are well known, the toxicity profile of emerging immune therapies is not fully elucidated. They have been associated with atypical side effects labeled collectively as immune-related adverse events (irAEs).

Evaluation of Nivolumab for Ototoxic Effects: An Animal Study in Rats

OBJECTIVES

The aim of this study was to assess whether nivolumab is ototoxic in rats and whether this ototoxicity is dose-dependent.

MATERIALS AND METHODS

Twelve rats were divided into two groups: Group 1 (control group, 6 rats, 12 ears) received intraperitoneal saline for 14 days. Group 2 (study group, 6 rats, 12 ears) and received two doses of 3 mg/kg intraperitoneal nivolumab within 14 days. Auditory brainstem responses (ABRs) were performed preoperatively and 4 and 8 weeks postoperatively. We compared between the groups, morphologic appearance of spiral ganglion cells and organ of Corti and density of spiral ganglion cells (measured with conventional light microscope connected to a personal computer).

RESULTS

In our control group, both spiral ganglion and organ of corti had a normal morphological appearance. In our study group, spiral ganglion cells had a normal morphological appearance. However, some sections showed possibly mild degenerative changes in the organ of corti. Of 12 samples in the study group, four had a significant loss of density of spiral ganglion cells compared to the control group. The baseline ABR thresholds did not significantly differ between the groups (p=0.713). There was no statistically significant difference between the groups regarding ABR thresholds at week 4 (p=0.347). However, a statistically significant difference was observed in the ABR thresholds at week 8 (p=0.045).

CONCLUSION

The results of our study showed that nivolumab treatment has ototoxic effects. Based on our results, we recommend monitoring the changes in the hearing ability of chemotherapy patients.

Sudden Otovestibular Dysfunction in 3 Metastatic Melanoma Patients Treated With Immune Checkpoint Inhibitors

Immune-related adverse events have been described in 86%-96% of high-risk melanoma patients treated with immune checkpoint inhibitors (ICI), while in 17%-59% of cases these are classified as severe or even life-threatening. The most common immune-related adverse events include diarrhea, fatigue, hypothyroidism, and hepatitis. Bilateral uveitis and unspecific vertigo have been described in 1% of cases, respectively, in the pivotal studies of ICIs, but the affection of the vestibule-cochlear system has not been reported before. In this case series, we present 3-stage IV melanoma patients with sudden onset of otovestibular dysfunction (hearing loss and vestibulopathy), partly combined with uveitis because of ICIs. We describe detailed diagnostic work-up and therapeutic interventions and discuss possible pathogenic mechanisms of this rare and disabling event.

Immune Checkpoint Inhibitor-induced Bilateral Vestibulopathy

Checkpoint inhibitors (CPI), such as anti-programmed death-1 and anti-cytotoxic T-lymphocyte antigen-4antibodies cause serious, rarely fatal immune-related adverse events (irAE) potentially in all organ systems. Neurological immune-related adverse events occur in 1%-5% of patients on CPI therapy and may present with dramatic clinical symptoms of the sensory organs. After exclusion of other causes, a high-dose treatment with corticosteroids is crucial for clinical outcome with lower risk of sequelae. We present a severe case of CPI-related ongoing and most likely irreversible bilateral vestibular affection. A 59-year-old male melanoma patient with brain metastasis undergoing immunotherapy with anti-cytotoxic T-lymphocyte antigen-4 and anti-programmed death-1 antibodies developed severe debilitating rotatory vertigo. Bilateral vestibulopathy was diagnosed as a result of the CPI therapy after a thorough analysis including magnetic resonance imaging, laboratory tests of blood and cerebrospinal fluid as well as neurological and otorhinolaryngology examinations. The vertigo improved slightly during a 10-day course of steroid therapy and intensive balance training but did not resolve completely.

Immune-mediated ototoxicity associated with immune checkpoint inhibitors in patients with melanoma

Immune checkpoint inhibitors (ICIs) are associated with a range of organ-specific toxicities known as immune-related adverse events (irAEs). Immune-mediated ototoxicity from ICIs is poorly described. Herein, we describe the clinical presentation, diagnostic evaluation and management of six ICI-treated patients who developed immune-mediated ototoxicity, identified by a multidisciplinary immune-related toxicity team. This is the largest case series to date and identifies bilateral high-frequency hearing loss and tinnitus as the most common reported symptoms and can be associated with abnormal speech reception thresholds and word recognition ability on audiogram in select patients. We propose multidisciplinary evaluation of patients with suspected otologic irAEs including referral to otolaryngology, audiometry evaluation±magnetic resonance imaging for evaluation of suspected immune-mediated ototoxicity.

Cranial Nerve Disorders Associated With Immune Checkpoint Inhibitors

OBJECTIVE

To describe the spectrum, treatment, and outcome of cranial nerve disorders associated with immune checkpoint inhibitor (Cn-ICI).

METHODS

This nationwide retrospective cohort study on Cn-ICI (2015-2019) was conducted using the database of the French Refence Center. In addition, a systematic review of the literature (MEDLINE, Scopus, and Web of Science) for records published between 2010 and 2019 was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the search terms cranial nerve or neuropathy or palsy and immune checkpoint inhibitors.

RESULTS

Among 67 cases with ICI-related neurologic toxicities diagnosed in our reference center, 9 patients with Cn-ICI were identified (7 men, 78%, median age 62 years [range 26-82 years]). Patients were receiving a combination of anti-cytotoxic T-lymphocyte antigen 4 and anti-programmed cell death 1 (PD-1)/PD-1 ligand (n = 5, 56%) or anti-PD-1 antibodies alone (n = 4, 44%). Cn-ICI involved optic (n = 3), vestibulocochlear (n = 3), abducens (n = 2), facial (n = 2), and oculomotor (n = 1) nerves. Two patients had involvement of 2 different cranial nerves. Treatment comprised corticosteroids (n = 8, 89%), ICI permanent discontinuation (n = 7, 78%), plasma exchange (n = 2, 22%), and IV immunoglobulin (n = 1, 11%). Median follow-up was 11 months (range 1-41 months). In 3 cases (33%), neurologic deficit persisted/worsened despite treatment: 2 optic and 1 vestibulocochlear. Among cases from the literature and the present series combined (n = 39), the most commonly affected cranial nerves were facial (n = 13, 33%), vestibulocochlear (n = 8, 21%), optic (n = 7, 18%), and abducens (n = 4, 10%). Trigeminal, oculomotor, and glossopharyngeal nerves were less frequently affected (total n = 7).

CONCLUSION

Cranial nerve disorders can complicate treatment with ICIs. Approximately one-third of the patients had persisting deficits, most frequently involving hearing and vision loss.

Autoimmune inner ear disease: A systematic review of management

OBJECTIVES

The study systematically reviewed the existing literature on the management of autoimmune inner ear disease (AIED).

STUDY DESIGN

Systematic review.

METHODS

We performed a literature search of Embase, NCBI, Cochrane, and Web of Science databases from April 1990 to April 2020. Inclusion criteria included studies that were retrospective or prospective in nature evaluating the treatment of AIED with audiometric data measuring hearing outcomes during treatment. Hearing improvement was the primary study outcome and improvement in vestibular symptoms was the secondary study outcome.

RESULTS

Sixteen of 412 candidate articles were included in our study. Systemic steroid treatment is most commonly described. Alternative treatment modalities included intratympanic steroid treatment, methotrexate, cyclophosphamide, azathioprine, infliximab, etanercept, adalimumab, golimumab, methylprednisolone, rituximab, and anakinra.

CONCLUSION

Systemic corticosteroids are the first line treatment of AIED. Intratympanic steroids are a potential adjuvant or alternative treatment for patients who cannot tolerate or become refractory to steroid treatment. Steroid nonresponders may benefit from biologic therapy. Alternative treatment modalities including nonsteroidal immunosuppressants and biologics have been studied in small cohorts of patients with varying results. Prospective studies investigating the efficacy of biologic and nonsteroidal therapy are warranted.

LEVEL OF EVIDENCE

2.

Phase I Clinical Trial of Combination Propranolol and Pembrolizumab in Locally Advanced and Metastatic Melanoma: Safety, Tolerability, and Preliminary Evidence of Antitumor Activity

PURPOSE

Increased β-adrenergic receptor (β-AR) signaling has been shown to promote the creation of an immunosuppressive tumor microenvironment (TME). Preclinical studies have shown that abrogation of this signaling pathway, particularly β2-AR, provides a more favorable TME that enhances the activity of anti-PD-1 checkpoint inhibitors. We hypothesize that blocking stress-related immunosuppressive pathways would improve tumor response to immune checkpoint inhibitors in patients. Here, we report the results of dose escalation of a nonselective β-blocker (propranolol) with pembrolizumab in patients with metastatic melanoma.

PATIENTS AND METHODS

A 3 + 3 dose escalation study for propranolol twice a day with pembrolizumab (200 mg every 3 weeks) was completed. The primary objective was to determine the recommended phase II dose (RP2D). Additional objectives included safety, antitumor activity, and biomarker analyses. Responders were defined as patients with complete or partial response per immune-modified RECIST at 6 months.

RESULTS

Nine patients with metastatic melanoma received increasing doses of propranolol in cohorts of 10, 20, and 30 mg twice a day. No dose-limiting toxicities were observed. Most common treatment-related adverse events (TRAEs) were rash, fatigue, and vitiligo, observed in 44% patients. One patient developed two grade ≥3 TRAEs. Objective response rate was 78%. While no significant changes in treatment-associated biomarkers were observed, an increase in IFNγ and a decrease in IL6 was noted in responders.

CONCLUSIONS

Combination of propranolol with pembrolizumab in treatment-naïve metastatic melanoma is safe and shows very promising activity. Propranolol 30 mg twice a day was selected as RP2D in addition to pembrolizumab based on safety, tolerability, and preliminary antitumor activity.

Unilateral autoimmune inner ear disease in a patient with lung cancer treated with nivolumab

A 69-year-old male presented with early stage non-small cell lung cancer in 2016. The tumor was resected; however, the patient experienced recurrence 2 years later and subsequently received paclitaxel/carboplatin concurrently with radiotherapy. Within weeks of completing this treatment, he developed a symptomatic pancoast tumor secondary to disease progression and commenced second line nivolumab. Following the second dose of nivolumab, he developed acute unilateral right hearing loss. He commenced intravenous methylprednisolone followed by a slow taper of oral prednisolone. With steroids, he noted a gradual improvement in hearing, confirmed by audiology. Restaging imaging post-nivolumab demonstrated a complete metabolic response. Two prior cases have reported bilateral sensorineural hearing loss post-immune checkpoint inhibitor (ICI). We postulate the hearing impairment relates to the development of autoimmune inner ear disease. To our knowledge, this is the only case of a patient experiencing unilateral loss of hearing following an ICI.

Anti-PD-1 Therapy Does Not Influence Hearing Ability in the Most Sensitive Frequency Range, but Mitigates Outer Hair Cell Loss in the Basal Cochlear Region

The administration of immune checkpoint inhibitors (ICIs) often leads to immune-related adverse events. However, their effect on auditory function is largely unexplored. Thorough preclinical studies have not been published yet, only sporadic cases and pharmacovigilance reports suggest their significance. Here we investigated the effect of anti-PD-1 antibody treatment (4 weeks, intraperitoneally, 200 μg/mouse, 3 times/week) on hearing function and cochlear morphology in C57BL/6J mice. ICI treatment did not influence the hearing thresholds in click or tone burst stimuli at 4–32 kHz frequencies measured by auditory brainstem response. The number and morphology of spiral ganglion neurons were unaltered in all cochlear turns. The apical-middle turns (<32 kHz) showed preservation of the inner and outer hair cells (OHCs), whilst ICI treatment mitigated the age-related loss of OHCs in the basal turn (>32 kHz). The number of Iba1-positive macrophages has also increased moderately in this high frequency region. We conclude that a 4-week long ICI treatment does not affect functional and morphological integrity of the inner ear in the most relevant hearing range (4–32 kHz; apical-middle turns), but a noticeable preservation of OHCs and an increase in macrophage activity appeared in the >32 kHz basal part of the cochlea.

Recurrent audiovestibular dysfunction and associated neurological immune-related adverse events in a melanoma patient treated with nivolumab and ipilimumab

BACKGROUND

Recurrent immunotherapy-induced audiovestibular toxicity despite cessation of therapy has not been reported.

METHODS

We report the first case of recurrent audiovestibular toxicity following immune-checkpoint inhibitor (ICI) therapy. The patient was seen with sudden bilateral hearing loss and disequilibrium. After ruling out other etiologies, he was diagnosed with audiovestibular and neurological immune-related adverse events (irAEs). He received systemic steroids, with significant hearing and balance recovery. Over the following 4 months, he experienced two other episodes of sudden bilateral hearing loss despite ICIs cessation. The second episode was treated with oral steroids, and hearing improved. On the third episode, he received oral and intratympanic steroids, and he was started on infliximab.

RESULTS

Audiogram 8 months following the last recurrence showed hearing improvement and stability.

CONCLUSION

Immunotherapy-induced ototoxicity may recur despite therapy cessation. High dose steroids remain the mainstay of treatment. If audiovestibular irAEs recur despite multiple courses of steroids, immunosuppressive agents may be considered.

Bilateral Sensorineural Hearing Loss Associated With Nivolumab Therapy for Stage IV Malignant Melanoma

OBJECTIVES

Present the case of a 67-year-old male with stage IV malignant melanoma who presented with uveitis and sensorineural hearing loss (SNHL) while on nivolumab and review the literature for likely etiologies.

METHODS

A retrospective case review was conducted. The current literature was accessed to inquire about possible pathologic mechanisms and treatment options.

RESULTS

A 67-year-old male with stage IV malignant melanoma was treated with nivolumab. During therapy, the patient presented with bilateral uveitis, vertigo, and bilateral moderate sloping to moderate-severe SNHL. After 4 cycles of nivolumab, restaging scans showed no evidence of disease. Nivolumab was discontinued. The patient was placed on a 3-week course of systemic high dose steroids and topical steroid eye drops. Both his uveitis and SNHL resolved after treatment. Nivolumab enhances the antitumor activity of T cells by inhibiting the programed death-1 receptor. While nivolumab has shown great promise in the treatment of many types of cancers, it has also been associated with many autoimmune side effects. We propose the etiology of this 67-year-old male's SNHL and uveitis are the result of an autoimmune process secondary to an augmented T cell response induced by nivolumab.

CONCLUSION

While immunotherapeutic agents such as nivolumab have shown great promise in the treatment of cancer, one should maintain an awareness and caution of autoimmune side effects such as uveitis and SNHL.

Ear and labyrinth toxicities induced by immune checkpoint inhibitors: a disproportionality analysis from 2014 to 2019

Aim: We aimed to systematically characterize ear and labyrinth toxicities after immune checkpoint inhibitors (ICIs) initiation. Materials & methods: Data were extracted from the US FDA Adverse Event Reporting System database. Disproportionality analysis including information component and reporting odds ratio (ROR) was performed to access potential signals. Results: In FDA Adverse Event Reporting System database, 284 records for ICIs-associated ear/labyrinth adverse events (AEs) were involved. In general, there was no significant association between total ICIs use and total ear and labyrinth AEs (ROR₀₂₅: 0.576). However, in ICIs monotherapy and polytherapy groups, signals were detected in several specific ear and labyrinth AEs. Conclusion: Total ear and labyrinth toxicities were not significantly reported with ICI immunotherapy, while class-specific ear toxicities were detected in some strategies.

Electrophysiological and inner ear MRI findings in patients with bilateral vestibulopathy

PURPOSE

Bilateral vestibulopathy (BV) is an uncommon disorder and the etiology remained idiopathic in most cases. Delayed 3D-FLAIR sequences have provided new insights into various inner ear diseases, allowing the evaluation of the endolymphatic space and the permeability of the blood-labyrinthine barrier (BLB). The aim of this study was to assess both the morphology of the endolymphatic space and the permeability of the BLB in patients with BV as evaluated by delayed 3D-FLAIR sequences.

METHODS

In this retrospective study, we performed 3D-FLAIR sequences 4 h after administering contrast media to 42 patients with BV. Two radiologists independently evaluated the morphology of the endolymphatic space (either vestibular atelectasis or endolymphatic hydrops) and the permeability of the BLB.

RESULTS

Morphologic anomalies of the endolymphatic space and vestibular blood-labyrinthine barrier impairment were observed in 59.6% of patients with BV. Bilateral vestibular atelectasis (VA) was found in 21 patients (50%), involving only the utricle and all three ampullas while the saccule was always observed with no sign of collapse: idiopathic BV (n = 19), aminoglycoside administration (n = 1) and few days following abdominal surgery (n = 1). One patient had bilateral vestibular malformation. BLB impairment was observed in five patients (11.9%): paraneoplastic (n = 1), lymphoma (n = 1), autoimmune (n = 1), and vestibular "neuritis" (n = 2). Seventeen patients (40.4%) had normal MRI with no endolymphatic space anomaly or BLB impairment.

CONCLUSION

Patients with BV presented with morphologic anomalies of the endolymphatic space or BLB impairment in 59.6% of patients.

Immune-Related Oral, Otologic, and Ocular Adverse Events

Emerging immunotherapy agents, such as immune checkpoint inhibitors, have shown remarkable promise in the treatment of various malignancies. These drugs selectively target different steps in the immune response cascade to upregulate the body's normal response to cancer. Due to the novelty of these therapeutic agents, their toxicity profile is less well understood.Meta-analysis results reveal that the overall prevalence of oral mucositis, stomatitis, and xerostomia is lower with checkpoint inhibitors compared to conventional chemotherapy, and head and neck radiation therapy. However, the widespread use of immunotherapy reveals new oral mucosal barrier adverse events, including bullous pemphigoid, mucous membrane pemphigoid, and lichenoid mucositis. Audiovestibular dysfunction can occur from autoimmune-mediated pathways of immunotherapy (adoptive cell) with limited treatment options. Such auditory complications can lead to speech recognition deficits and sensorineural hearing loss. Ocular toxicities are among the most common adverse events resulting from the use of these agents. The majority of ocular immune-related adverse events (irAEs) are mild, low-grade, non-sight threatening, such as blurred vision, conjunctivitis, and ocular surface disease. Serious and sight-threatening events, including corneal perforation, optic neuropathy, and retinal vascular occlusion, can occur but are infrequent. In this chapter, we review the current evidence on the clinical manifestations of oral, audiovestibular, and ocular immune-related adverse events (i.e., irAEs).

Investigation of the Ototoxic Effect of Pembrolizumab Using a Rat Model

Objective

Programmed cell death protein-1 (PD-1) inhibitors that have been recently introduced for the systemic treatment of head and neck cancers offer the advantage of fewer side effects and more effective treatment than chemotherapy drugs. A review of the literature shows that the ototoxic side effects of the PD-1 inhibitor have not yet been fully elucidated. In this study, we aimed to investigate whether the PD-1 inhibitor has ototoxic activity using both electrophysiological and histopathological methods.

Methods

A total of 24 rats, 12 for the study group, and 12 for the control group were included in the study. The study group was administered the PD-1 inhibitor. The auditory brainstem responses (ABR) of the study and control groups were evaluated. At the end of the study, all animals were sacrificed, and their cochleae were examined by immunohistochemical staining.

Results

In the study group, the ABR values ​​were 13.95 ± 2.70 before treatment, 15.83 ± 1.94 at week 4 of treatment (p=0.024), and 15.00 ± 1.06 at week 7 (p=0.157). Furthermore, according to immunohistochemical staining, the cochlear hair cells were reduced in the study group compared to the control group.

Conclusion

It was determined that the PD-1 inhibitor showed ototoxic activity during the course of treatment, but this was spontaneously resolved during follow-up. The clinical significance of these findings should be supported by human studies.

Pembrolizumab use for the treatment of advanced melanoma

INTRODUCTION

Until recently, overall long term survival in patients with stage IV melanoma was lower than 10%. However, the treatment of melanoma has evolved rapidly over the last few years, with the advent of inhibitors of BRAF and MEK and of immunotherapeutic agents including ipilimumab, nivolumab, and pembrolizumab. Areas covered: This is a comprehensive review of the literature on the role of pembrolizumab in melanoma. Pembrolizumab is a Programmed Death Receptor 1 (PD-1) directed monoclonal antibody which is approved by FDA and EMA for the treatment of patients with metastatic melanoma. Expert opinion: Phase II and III trials demonstrated that pembrolizumab is superior to ipilimumab in previously untreated patients and to chemotherapy in ipilimumab pre-treated patients. Unfortunately, prospectively validated predictive markers are lacking. Immune-related adverse events are particularly interesting and should be managed per the published guidelines. There are still many issues that remain unresolved including: when to stop treatment, biomarkers for choosing a single agent or combination therapy, the optimal schedule of ipilimumab in combination with anti-PD1 monoclonal antibodies, optimal management of adverse events, the role of immunotherapy in specific populations, the optimal sequence of immunotherapy and the BRAF/MEK inhibitor combination in patients.

Sudden hearing loss in a melanoma patient on pembrolizumab: an etiology not to be omitted in the differential diagnosis

Immune checkpoint inhibitors have emerged as a promising therapeutic option for metastatic cancers. However, they have been associated with inflammatory adverse reactions in various organ systems. A recent article reported a case of sudden bilateral hearing loss that occurred in a patient with metastatic melanoma being treated with pembrolizumab. The authors attributed that complication to an autoimmune reaction secondary to the treatment. This commentary discusses the importance of considering the diagnosis of leptomeningeal metastasis in patients with metastatic melanoma who present with new cranial nerve deficits.

The safety of anti PD-1 therapeutics for the treatment of melanoma

INTRODUCTION

The introduction of immunotherapies into clinical practice has substantially improved the prognosis of metastatic melanoma patients as well as patients suffering from other cancers. The two FDA-approved checkpoint inhibitors against PD-1 (nivolumab and pembrolizumab) have been shown to significantly improve patient survival while being less toxic than previous treatment options. Areas covered: The current scientific literature on safety and adverse events (AEs) related to anti-PD-1 therapies has been investigated with special attention to case reports and to the latest results announced at the major clinical cancer and melanoma meetings, including ASCO (American Society of Clinical Oncology), ESMO (European Society of medical Oncology) and EADO (European Association of Dermato-Oncology) annual meetings. Expert opinion: Even though anti-PD-1 therapies are better tolerated than conventional chemo- or other immune-therapies, they still induce a plethora of AEs. Given the mechanism of action, it is supposed that most if not all of them are immune related. Fortunately, the majority are mild and manageable. However, due to the increase in patients' life expectancy, there is a substantial need to understand and prevent severe cutaneous, pulmonary, neurological and other AEs which have major impact on the quality of life. The safety profile after long term use of these medications is still unclear. In addition, non-steroid based immune interventions to control autoimmunity are still to be developed.