Guillain-Barré Syndrome Related to Nivolumab: Case Report of a Patient With Urothelial Cancer and Review of the Literature

Synergistic effects of immune checkpoints and checkpoint inhibitors in inflammatory neuropathies: Implications and mechanisms

Immune checkpoint molecules play pivotal roles in the regulation of immune homeostasis. Disruption of the immune checkpoints causes autoimmune/inflammatory as well as malignant disorders. Over the past few years, the immune checkpoint molecules with inhibitory function emerged as potential therapeutic targets in oncological conditions. The inhibition of the function of these molecules by using immune checkpoint inhibitors (ICIs) has brought paradigmatic changes in cancer therapy due to their remarkable clinical benefits, not only in improving the quality of life but also in prolonging the survival time of cancer patients. Unfortunately, the ICIs soon turned out to be a "double-edged sword" as the use of ICIs caused multiple immune-related adverse effects (irAEs). The development of inflammatory neuropathies such as Guillain-Barré syndrome (GBS) and Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP) as the secondary effects of immunotherapy appeared very challenging as these conditions result in significant and often permanent disability. The underlying mechanism(s) through which ICIs trigger inflammatory neuropathies are currently not known. Compelling evidence suggests autoimmune reaction and/or inflammation as the independent risk mechanism of inflammatory neuropathies. There is a lack of understanding as to whether prior exposure to the risk factors of inflammatory neuropathies, the presence of germline genetic variants in immune function-related genes, genetic variations within immune checkpoint molecules, the existence of autoantibodies, and activated/memory T cells act as determining factors for ICI-induced inflammatory neuropathies. Herein, we highlight the available pieces of evidence, discuss the mechanistic basis, and propose a few testable hypotheses on inflammatory neuropathies as irAEs of immunotherapy.

Immune Checkpoint Inhibitor-related Guillain-Barré Syndrome: A Case Series and Review of the Literature

Immune checkpoint inhibitors (ICIs) have been approved for the treatment of various malignancies with promising clinical outcomes. Treatment can, however, be accompanied by serious immune-related adverse events. Neurological adverse events like Guillain-Barré syndrome (GBS) are rare but potentially life-threatening. We present 3 cases of ICI-related GBS; review cases described in current literature, and discuss treatment strategies. Three patients developed GBS after ICI treatment. The first case with pembrolizumab had a fatal outcome despite treatment with multiple regimens, including steroids and intravenous immunoglobulin (IVIg). The other 2 cases with nivolumab-induced and pembrolizumab-induced GBS, respectively, responded well to treatment with IVIg and steroids. In the current literature, a total of 31 other cases were found. Treatment for ICI-related GBS mostly consisted of concurrent IVIg and steroids (44%), which led to clinical improvement in 73%. Most patients recovered with remaining symptoms (68%), while 10 patients developed respiratory failure (29%) and 6 patients (18%) died. ICI-related GBS should be suspected in patients on ICI treatment who develop subacute progressive weakness of the limbs, sensory loss, and areflexia. On the basis of the guidelines recommendations and our review of the literature, we advise first-line therapy with concurrent IVIg 0.4 g/kg/d for 5 days and prednisolone 1-2 mg/kg/d. Discontinuation of immunotherapy after ICI-related GBS is advised.

Guillain-Barré Syndrome-Like Polyneuropathy Associated with Immune Checkpoint Inhibitors: A Systematic Review of 33 Cases

Immune checkpoint inhibitors (ICIs) have been increasingly used in the treatment of various types of tumors with favorable results. But these treatments also led to a variety of immune-related adverse events (irAEs). Neurological irAEs such as Guillain-Barré Syndrome are rare and may have serious consequences once they occur. A systematic literature search was performed in PubMed and Embase for all case reports of GBS associated with ICIs published in English reporting on human beings from 1990 up to date. A total of 30 case reports (total patients = 33) were used for final analysis. The included cases were from 11 countries, covering 10 tumor types, with melanoma accounting for the largest number. The mean age was 62.2 ± 11.1 years old, and males were dominant (male: 26 and female: 7). The median time of initial symptoms was 8.2 weeks after the 1^st dose of ICIs. The most common manifestations of GBS associated with ICIs were weakness, hyporeflexia or areflexia, and paresthesia in order. The GBS subtypes suggested by electrophysiological results were acute inflammatory demyelinating polyneuropathy (AIDP), acute motor axonal neuropathy (AMAN), and Miller Fisher syndrome (MFS). The protein level of CSF in patients with GBS related to ICIs was 180.68 ± 152.51 mg/dl. Immediate termination of ICIs followed by intravenous immunoglobulin was the preferred treatment option. 72.7% of patients recovered or had residual mild dysfunction after treatment. Elderly male patients with melanoma were most likely to develop ICI-related GBS. The specific neurological symptoms, CSF analysis, and electrophysiological examination were important means of diagnosis.

Atezolizumab-induced encephalitis in a patient with metastatic breast cancer: a case report and review of neurological adverse events associated with checkpoint inhibitors

Immune-mediated encephalitis as an adverse event due to checkpoint inhibitors is very rare. We describe herein the case of a 38-year-old woman with metastatic triple-negative breast cancer who developed seizures and somnolence twelve days after receiving the first dose of Atezolizumab. Work up ruled out all infectious etiologies, and the patient was eventually diagnosed with immune-mediated meningoencephalitis. Symptoms recovered with a high-dose of steroids, and she was found to have an excellent response on follow-up imaging, which raised the question of whether a relationship exists between the occurrence, and severity of the adverse event and the response to treatment. Only a few other cases of atezolizumab-related encephalitis have been published. Early recognition and treatment are crucial; the reason why we are describing this case along with a review of the literature and a review on all the neurological immune-related adverse events due to the different checkpoint inhibitors.

Polyradiculoneuropathy induced by immune checkpoint inhibitors: a case series and review of the literature

OBJECTIVE

The purpose of the present study is to report the clinical characteristics of polyradiculoneuropathy induced by immune checkpoint inhibitors (ICIs).

METHODS

We retrospectively reviewed lists of all inpatients with neurological immune-related adverse events (irAEs) treated at the neurology departments of three hospitals in January 2017 and December 2019. We also performed a review of the previous case reports with polyradiculoneuropathy induced by ICI therapy.

RESULTS

We had 4 patients with polyradiculoneuropathy following ICI therapy. We comprehensively reviewed our 4 patients and 32 previous case reports. There were 28 men and 8 women with a mean onset age of 61 years. ICI monotherapy was performed in 27 patients, whereas the combination of ICIs was administered in 9 patients. All patients except 2 showed limb weakness, which was observed symmetrically and predominantly in the legs rather than the arms. Bulbar involvement was observed in 7 patients. The laboratory findings were demyelination in electrophysiological studies and elevated protein with lymphocytes in the cerebrospinal fluid. Disease severity was ranked on the Hughes functional scale; 17 patients were grade 4 or greater. The treatment responses to corticosteroid and intravenous methylprednisolone were favorable. Intravenous immunoglobulin was also used in combination with steroids. Seven patients died, including 4 who on mechanical ventilation.

CONCLUSION

Polyradiculoneuropathy induced by ICIs has a distinct subset of neurological irAEs and requires early recognition.

Guillain-Barre syndrome induced by pembrolizumab and sunitinib: A case report

Pembrolizumab, an immune checkpoint inhibitor against the programmed death-1 pathway, has been used in combination with acitinib for the first-line treatment of advanced renal cell carcinoma. Neurotoxicity is a rare immune-related adverse event (irAE). The present study reports a case of Guillain-Barre syndrome (GBS) induced by pembrolizumab and sunitinib, and reviews other previous studies to elucidate the clinical characteristics and suitable management of this rare irAE. An advanced renal cell carcinoma patient who received several cycles of pembrolizumab combined with sunitinib developed limb weakness and numbness of the extremities, and was diagnosed with GBS by electrodiagnostic and cerebrospinal fluid examination. The patient improved after treatment with intravenous immunoglobulin along with prednisone. To the best of our knowledge, this is the first case of GBS during treatment with pembrolizumab in combination with sunitinib in advanced renal cell carcinoma.

Safe Transition to Pembrolizumab following Ipilimumab-Induced Guillain-Barré Syndrome: A Case Report and Review of the Literature

Background

Immune checkpoint inhibitors are novel therapies with indications for treating several solid cancers. They are associated with immune-related adverse events, which are generally well tolerated. Though rare, severe side effects may be life-threatening. One such adverse event is Guillain-Barré syndrome, which requires cessation of the immunotherapy and intravenous immunoglobulin and/or high-dose steroids to treat. No recommendations have been published regarding restarting cancer treatment after development of immunotherapy-induced Guillain-Barré syndrome.

Case Presentation

A 71-year-old gentleman with recurrent, stage IIIB melanoma was started on ipilimumab (cytotoxic T lymphocyte antigen-4 inhibitor) for adjuvant treatment following radical neck dissection and radiation therapy. After completing his third cycle of ipilimumab, he developed rapidly progressive ascending paralysis. He was diagnosed with ipilimumab-induced atypical Guillain-Barré syndrome and was treated with intravenous immunoglobulin and corticosteroids. Ipilimumab was discontinued, and the patient was monitored via surveillance imaging, as there was no evidence of active disease at that time. Several months later, he was found to have recurrent disease involving the lung, requiring right lower lobectomy. Restaging revealed thoracic lymph node involvement, and he was then started on pembrolizumab (programmed cell death protein-1 inhibitor). He experienced a complete tumoral response to pembrolizumab, and he tolerated treatment well without recurrent weakness.

Conclusions

Guillain-Barré syndrome is a rare but severe complication associated with immunotherapy. Our findings suggest that in patients with a history of ipilimumab-induced Guillain-Barré syndrome, pembrolizumab may possibly be a safe and effective alternative for cancer therapy.