Bullous pemphigoid secondary to pembrolizumab mimicking toxic epidermal necrolysis

Immune checkpoint inhibitor-induced epidermal necrolysis: A narrative review evaluating demographics, clinical features, and culprit medications

Immune checkpoint inhibitors (ICIs) have transformed cancer treatment but can cause immune-related adverse events (irAEs). Severe cutaneous irAEs, including epidermal necrolysis, are rare but potentially life-threatening. There is limited understanding of the clinical features and management of ICI-induced Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), so we aimed to analyze 95 cases of ICI-induced SJS/TEN (35 cases of SJS, 26 cases of TEN, two cases of SJS/TEN overlap, and 32 cases of unspecified) to increase knowledge of this condition among oncologists and dermatologists. We conducted a comprehensive search of PubMed for all relevant case reports published until the end of December 2022, and collected data on patient demographics, cancer type, ICI regimen, time to onset of SJS/TEN, clinical presentation, management strategies, and outcomes. PD-1 inhibitors were the most common ICIs associated with SJS/TEN (58.9%), followed by the combination of PD-1 and CTLA-4 inhibitors (11.6%), and PD-L1 inhibitors (6.3%). Lung cancer and melanoma were the most frequent malignancies treated (35.8% and 25.4%, respectively). SJS/TEN occurred most frequently within the first 4 weeks (51.7%), and corticosteroid monotherapy was the most commonly chosen systemic treatment (56.4%). The overall mortality rate of ICI-induced SJS/TEN was 30.8%. Our findings highlight the frequency and severity of ICI-induced SJS/TEN and the urgent need for predictive molecular biomarkers aimed at preventive measures and early intervention.

Bullous Pemphigoid in a Centenarian Male Simulating Toxic Epidermal Necrolysis

Bullous pemphigoid (BP) is one of the most common autoimmune blistering diseases and classically presents as large, tense bullae. We report a case of BP with toxic epidermal necrolysis (TEN)-like manifestations in a 103-year-old male, the oldest known patient to present with an acute onset of BP. Our patient presented with extensive erosive lesions comprising 12% of the total body surface area, raising suspicion of TEN and Staphylococcal scalded skin syndrome. Detailed clinical, histological, and immunofluorescence analyses were performed, confirming a diagnosis of BP. Atypical presentations of blistering disorders can be a diagnostic challenge and require the use of histologic and direct immunofluorescence testing to distinguish between clinically similar cutaneous diseases. Proper diagnosis is essential to ensure appropriate management and patient care.

Analysis of the clinical characteristics of pembrolizumab-induced bullous pemphigoid

Background

Pembrolizumab, a programmed cell death protein 1 checkpoint inhibitor, is a novel drug used to treat a variety of advanced malignancies. However, it can also result in many immune-related adverse events, with cutaneous toxicities being the most frequent. Regarding pembrolizumab-induced skin adverse reactions, bullous pemphigoid (BP) has the worst effects on quality of life. Recently, there have been more and more reports of BP incidents resulting from pembrolizumab therapy in patients with cancer. This study aimed to define the clinical characteristics, diagnosis and management of pembrolizumab-induced BP and identify potential differences between classical BP and pembrolizumab-induced BP.

Methods

Case reports, case series, and case analyses of pembrolizumab-induced BP up to 10 December 2022 were collected for retrospective analysis.

Results

Our study included 47 patients (33 males and 14 females) from 40 studies. The median age was 72 years (range 42-86 years). The median time to cutaneous toxicity was 4 months (range 0.7-28 months), and the median time to bullae formation was 7.35 months (range 0.7-32 months). The most common clinical features were tense bullae and blisters (85.11%), pruritus (72.34%), and erythema (63.83%) on the limbs and trunk. In 20 of the 22 cases tested, the serum anti-BP180 autoantibodies were positive. However, in 10 cases (91.90%, 10/11) the circulating autoantibodies of anti-BP230 were negative. 40 patients had skin biopsies and the skin biopsy revealed subepidermal bullae or blister eosinophil infiltration in 75.00% of patients with pembrolizumab-induced BP, 10.00% of patients with lymphocyte infiltration and 20.00% of patients with neutrophil infiltration. There were 20 patients (50%) with eosinophilic infiltration around the superficial dermis vessels, 8 patients (20.00%) with lymphocyte infiltration around the superficial dermis vessels, and 4 patients (10.00%) with neutrophil infiltration around the superficial dermis vessels. Direct immunofluorescence detected linear immunoglobulin G (IgG) IgG and/or complement C3 along the dermo-epidermal junction in 36 patients (94.74%) with BP. IgG positivity was detected by indirect immunofluorescence in 81.82% of patients with BP. All patients were in complete remission (95.65%,44/46) or partial remission (4.35%, 2/46) of BP, whereas 9/46 patients had a relapse or refractory. The majority of patients achieved BP remission after discontinuation of pembrolizumab with a combination of topically and systemically administered steroid treatments, or other medications. The median duration of BP remission was 2 months (range 0.3-15 months).

Conclusion

A thorough diagnosis of pembrolizumab-induced BP should be made using clinical signs, biochemical markers, histopathological and immunopathological tests. Pembrolizumab-induced BP had similar clinical characteristics to classic BP. Temporary or permanent discontinuation of pembrolizumab therapy may be required in patients with perbolizumab-induced BP depending on the severity of BP and the response to medication. Pembrolizumab-induced BP may be effectively treated using topical and systemic steroid treatments in combination with other medications (e.g., doxycycline, niacinamide, dapsone, rituximab, intravenous immunoglobulins, dupilumab, cyclophosphamide, methotrexate, mycophenolate mofetil, and infliximab). Clinicians should provide better management to patients with BP receiving pembrolizumab to prevent progression and ensure continuous cancer treatment.

Association of Bullous Pemphigoid With Immune Checkpoint Inhibitor Therapy in Patients With Cancer: A Systematic Review

Importance

There is limited information on immune checkpoint inhibitor-induced bullous pemphigoid (ICI-BP) in patients with cancer, with most existing studies being case reports or small case series from a single institution. Prior review attempts have not approached the literature in a systematic manner and have focused only on ICI-BP secondary to anti-programmed cell death 1 (PD-1) or programmed cell death ligand 1 (PD-L1) therapy. The current knowledge base of all aspects of ICI-BP is limited.

Objective

To characterize the risk factors, clinical presentation, diagnostic findings, treatments, and outcomes of ICI-BP in patients with cancer as reported in the current literature.

Evidence Review

A systematic review was performed using PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Articles reporting data on individual patients who met preestablished inclusion criteria were selected, and a predefined set of data was abstracted. When possible, study results were quantitatively combined.

Findings

In total, 70 studies reporting data on 127 individual patients undergoing ICI therapy for cancer (median [IQR] age, 71 [64-77] years; 27 women [21.3%]) were included. In pooled analyses, patients ranged in age from 35 to 90 years. Immune checkpoint inhibitor-induced bullous pemphigoid often occurred during the course of anti-PD-1, PD-L1, or cytotoxic T lymphocyte-associated antigen 4 therapy but was also found to develop up to several months after treatment cessation. Prodromal symptoms, such as pruritus or nonspecific skin eruptions, were found in approximately half of the patient population. Histopathologic or serologic testing, when undertaken, was a helpful adjunct in establishing diagnosis. Treatment with immunotherapy was discontinued after ICI-BP development in most patients. The most common treatments were systemic and topical corticosteroids. Steroid-sparing therapies, such as antibiotics and other systemic immunomodulators, were also used as adjuvant treatment modalities. Biologic and targeted agents, used predominantly in cases refractory to treatment with corticosteroids, were associated with marked symptomatic improvement in most patients.

Conclusions and Relevance

The results of this systematic review suggest that ICI-BP often poses a therapeutic challenge for patients with cancer who are receiving immunotherapy. Further research on the early recognition, diagnosis, and use of targeted treatment modalities will be essential in developing more personalized treatment options for affected patients while minimizing morbidity and mortality.

Skin Manifestation Induced by Immune Checkpoint Inhibitors

In accordance with recent therapeutic progress of immune checkpoint inhibitors for certain cancers, various disorders are induced as immune-related adverse events (irAEs) affecting the skin, gut, thyroid gland, lung, and liver. Among such irAEs, mucocutaneous manifestation is the most common. Cutaneous manifestations are categorized into several groups, ie, inflammatory reactions, immunobullous reactions, alterations of epidermal keratinocytes, and alterations of epidermal melanocytes; however, there are additionally various cutaneous toxicities, unclassified into those groups. Blocking of programmed cell death 1 (PD-1)/programmed cell death ligand 1(PDL1) can lead to the induction of autoimmune reaction, via activation of cytotoxic T cells, inhibition of regulatory T cell function, and alteration of cytokine balance. Similarly, blockade of cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) reduces the suppressive function of regulatory T cells. Due to those mechanisms, various autoimmune conditions can be induced, in addition to nonspecific drug eruptions. Dermatologists should be aware of various types of those mucocutaneous manifestations, either common or rare, as well as the management of such conditions. Herein, various mucocutaneous manifestations of irAEs and cases involving Japanese patients have been described, based on a single institute's experience.

Strategies to Improve Outcomes of Bullous Pemphigoid: A Comprehensive Review of Clinical Presentations, Diagnosis, and Patients' Assessment

Bullous pemphigoid (BP) is the most frequent autoimmune bullous disease mainly affecting elderlies. Diagnosis usually results from clinical features, histological examination, and the quantification of circulating typical autoantibodies, due to its higher incidence in elderly patients, bullous pemphigoid treatment and management still represents a challenge due to the higher frequency of several comorbidities in this group of patients, which may also be linked to a reduced tolerance to BP treatments. Hence, an early diagnosis and a prompt correct treatment are mandatory to reach better clinical outcomes and improve as much as possible BP outcomes. Herein, we carried out a comprehensive literature review about the known clinical presentations, diagnosis, assessment and monitoring procedures used in daily clinical practice in patients with BP, to better define strategies to improve as much as possible BP clinical outcomes.

An Unusual TEN-Like Presentation of Juvenile Bullous Pemphigoid: A Diagnostic Challenge

Bullous pemphigoid (BP) is an acquired autoimmune bullous disorder rarely seen in the pediatric population. It usually presents as large and tense bullae, predominantly distributed in the acral areas. Herein, we describe a case of childhood BP with an atypical presentation mimicking toxic epidermal necrolysis (TEN). This case shows us that juvenile BP should be considered in the differential diagnosis of TEN in children, particularly if there are unusual features and an intractable course.

Pembrolizumab-induced Toxic Epidermal Necrolysis in a Patient with Metastatic Esophageal Adenocarcinoma

Adverse cutaneous reactions associated with the immune checkpoint inhibitor (ICI) pembrolizumab are well documented, yet life-threatening reactions such as Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are infrequent.1,2 We present a case of pembrolizumab-induced TEN in a patient with metastatic esophageal adenocarcinoma who was successfully treated with cyclosporine and systemic corticosteroids.

Bullous Pemphigoid in Patients Receiving Immune-Checkpoint Inhibitors and Psoriatic Patients—Focus on Clinical and Histopathological Variation

Background: The most common autoimmune blistering disease, bullous pemphigoid (BP), shows an increased prevalence in psoriatic patients and oncologic patients undergoing immune-checkpoint blockade (ICB). Even though the same autoantigens (BP180/BP230) are detectable, it remains obscure whether clinical or histopathological differences exist between these different groups of BP patients. In this study, we strived to analyze this matter based on own data and previously published reports. Methods: We performed an institutional chart review from 2010–2020 to identify BP patients with psoriasis (n = 6) or underlying ICB (n = 4) and matched them with idiopathic cases of BP (n = 33). We compared clinical characteristics, subtypes, and dermatopathological determinants (e.g., tissue eosinophilia/neutrophilia, papillary edema, lymphocytic infiltration) among the groups. Results: ICB-associated BP affects men more often and might show mucosal involvement more frequently. We found no statistically significant dermatopathological differences among the groups. Conclusions: Clinicians should be aware of an increased risk of BP in patients with psoriasis and oncologic patients receiving ICB; atypical pruritic skin lesions should prompt a workup including a skin biopsy for histopathology and direct immunofluorescence in these patients. Larger studies might be necessary to detect slight dermatopathological variation.

Adverse cutaneous toxicities by PD-1/PD-L1 immune checkpoint inhibitors: Pathogenesis, Treatment, and Surveillance

Introduction-The therapeutic use of humanized monoclonal programmed cell death 1 (PD-1) (pembrolizumab, and nivolumab) and programmed cell death ligand-1 (PD-L1) (atezolizumab, avelumab, durvalumab) immune checkpoint inhibitors (ICPi) as potent anticancer therapies is rapidly increasing. The mechanism of signaling of anti-PD-1/PD-L1 involves triggering cytotoxic CD4+/CD8 + T cell activation and subsequent abolition of cancer cells which induces specific immunologic adverse events that are specific to these therapies. These drugs can cause numerous cutaneous reactions and are characterized as the most frequent immune-related adverse events (irAEs). Majority of cutaneous irAEs range from nonspecific eruptions to detectible skin manifestations, which may be self-limiting and present acceptable skin toxicity profiles, while some may produce life-threatening complications.Objective-.This review aims to illuminate the associated cutaneous irAEs related to drugs used in oncology along with the relevant mechanism(s) and management.Areas covered-Literature was searched using various databases including Pub-Med, Google Scholar, and Medline. The search mainly involved research articles, retrospective studies, case reports, and clinicopathological findings. With this review article, an overview of the cutaneous irAEs with anti-PD-1/PD-L1 therapy, as well as suggestions, have been provided, so that their recognition at early stages could help in better management and would prevent treatment discontinuation.Article highlightsCutaneous adverse effects are the most prevalent immune-related adverse events induced by anti-PD-1/PD-L1 immune-checkpoint antibodies.Cutaneous toxicities mainly manifest in the form of maculopapular rash and pruritus.More specific cutaneous complications can also occur, including vitiligo, worsened psoriasis, lichenoid dermatitis, mucosal involvement (e.g., oral lichenoid reaction), dermatomyositis, lupus erythematosus.Cutaneous manifestations can be life-threatening including Stevens-Johnson syndrome/toxic epidermal necrolysis (TEN).Dermatologic toxicities are usually mild, readily manageable, and rarely result in significant morbidity.Adequate management of the cutaneous adverse event and recognition in early stages could lead to the prevention of worsening of the lesions and limit treatment disruption.

A Rare Case of Bullous Pemphigoid Secondary to Checkpoint Inhibitor Immunotherapy: A Tense Situation

Bullous pemphigoid is a serious and rare complication of immunotherapy. Here, we present a case of bullous pemphigoid secondary to ipilimumab/nivolumab checkpoint inhibitor therapy in a patient with metastatic melanoma. Immune checkpoint inhibitor therapy is more widely used now to treat cancer patients, bringing more challenging cases of adverse events associated with their use. Bullous pemphigoid can be a difficult diagnosis to make in the initial stages as the rash is similar to other red rashes before transforming into the typical appearance of a blister. As bullous pemphigoid can be a life-threatening adverse event, early identification is key to increasing patient survival.

Refractory Bullous Pemphigoid in a Patient with Metastatic Lung Adenocarcinoma Treated with Pembrolizumab

We present the case of a 73-year-old male patient with a history of tobacco use who presented with a central nervous system mass that was confirmed to be a lung adenocarcinoma metastasis. High PD-L1 expression as well as negativity to other targetable drivers led to initiation of pembrolizumab monotherapy and ablative stereotactic radiation therapy on oligo-residual disease, achieving a complete response after 2 years of therapy. Following discontinuation of systemic treatment, the patient developed widespread desquamative plaques. A skin biopsy revealed subepidermal blistering and eosinophilic infiltration in conjunction with C3 and IgG depositions on the basement membrane, detected by immunofluorescence. A diagnosis of bullous pemphigoid was obtained, and systemic corticosteroids were administered with lesion progression. Infliximab was also administered without meaningful clinical improvement. Metronomic cyclophosphamide achieved a complete resolution of skin lesions and up to this day the patient continues with tumor control and is free of dermatological findings. In conclusion, bullous pemphigoid is a very rare dermatological adverse effect related with pembrolizumab treatment. Only two cases, including this one, have been reported, especially with this medication for the treatment of non-small cell lung cancer. With more reported cases, management strategies can be optimized even in the steroid refractory setting.