Paraneoplastic Pemphigus Revealed by Anti-programmed Death-1 Pembrolizumab Therapy for Cutaneous Squamous Cell Carcinoma Complicating Hidradenitis Suppurativa

Defining D-irAEs: consensus-based disease definitions for the diagnosis of dermatologic adverse events from immune checkpoint inhibitor therapy

With an increasing number of patients eligible for immune checkpoint inhibitors, the incidence of immune-related adverse events (irAEs) is on the rise. Dermatologic immune-related adverse events (D-irAEs) are the most common and earliest to manifest, often with important downstream consequences for the patient. Current guidelines lack clarity in terms of diagnostic criteria for D-irAEs. The goal of this project is to better define D-irAE for the purposes of identification, diagnosis, and future study of this important group of diseases.The objectives of this project were to develop consensus guidance for an approach to D-irAEs including disease definitions and severity grading. Knowing that consensus among oncologists, dermatologists, and irAE subspecialists would be critical for usability, we formed a Dermatologic irAE Disease Definition Panel. The panel was composed of 34 experts, including oncologists, dermatologists, a rheumatologist, and an allergist/immunologist from 22 institutions across the USA and internationally. A modified Delphi consensus process was used, with two rounds of anonymous ratings by panelists and two virtual meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness, and accuracy on 9-point scales in electronic surveys and provided free text comments. A working group aggregated survey responses and incorporated them into revised definitions. Consensus was based on numeric ratings using the RAND/UCLA Appropriateness Method with prespecified definitions.Following revisions based on panelist feedback, all items received consensus in the second round of ratings. Consensus definitions were achieved for 10 core D-irAE diagnoses: ICI-vitiligo, ICI-lichen planus, ICI-psoriasis, ICI-exanthem, ICI-bullous pemphigoid, ICI-Grover's, ICI-eczematous, ICI-eruptive atypical squamous proliferation, ICI-pruritus without rash, and ICI-erosive mucocutaneous. A standard evaluation for D-irAE was also found to reach consensus, with disease-specific exceptions detailed when necessary. Each disorder's description includes further details on disease subtypes, symptoms, supportive exam findings, and three levels of diagnostic certainty (definite, probable, and possible).These consensus-driven disease definitions standardize D-irAE classification in a useable framework for multiple disciplines and will be the foundation for future work. Given consensus on their accuracy and usability from a representative panel group, we anticipate that they can be used broadly across clinical and research settings.

Immunomodulatory Plant Natural Products as Therapeutics against Inflammatory Skin Diseases

Frequently occurring inflammatory skin conditions such as psoriasis, dermatitis, acne, including skin cancer, wounds and other disorders arising out of premature skin aging, deteriorate skin health and adversely impact human life. Even though several synthetic compounds have evolved for treating these skin conditions, natural-product-based therapeutics are gaining popularity with growing evidence of their efficacy and safety for treating skin disorders. Many of these inflammatory skin diseases have underlying disturbances in our immune system and immunomodulatory natural products provide solutions for their effective treatment and aid in understanding the underlying mechanism of such inflammatory skin conditions. Based on this premise, the present review summarizes the possible application of plant-derived immunomodulatory compositions and single molecules for treating inflammatory skin conditions. In vitro, in vivo and mechanistic studies reported the application of selected plant-derived natural products for the treatment of inflammatory skin disorders including, cancer and infections. Several online databases including PubMed, Google Scholar, and Science Direct have been searched for gathering the information covered in this review. Empirical studies demonstrated that most of these natural compounds exhibited therapeutic properties through their immunomodulatory and anti-inflammatory potential supplemented often with anti-microbial, anti-neoplastic, and anti- oxidant activities. Overall, plant-based natural products discussed here are capable of modulating the immune system to minimize or completely suppress the pro-inflammatory markers, scavenge free radicals (ROS), prevent bacteria, fungal, and virus-derived skin infections and often regress skin cancer through the induction of apoptosis. The challenges and opportunities associated with the application of plant-based immunomodulators for skin applications and their safety considerations are also discussed here. The present study indicated that immunomodulatory plant natural products being biologically validated ligands against various biological targets manifested in inflammatory skin diseases, offer an effective, safe and affordable treatment for such disorders affecting skin health. However, further clinical evaluations are needed to substantiate these findings.

Immune checkpoint inhibitor-induced cutaneous toxicities: a review of histopathologic and clinical features

Immune checkpoint inhibitors (ICIs) represent an emerging treatment option for a variety of cancer types. Through inhibition of programmed cell death protein 1 (PD-1), programmed cell death ligand 1 (PD-L1), and/or cytotoxic lymphocyte-associated antigen-4 (CTLA-4), ICIs activate the host's immune system causing a heightened anti-tumor response. However, off-target effects of ICIs can result in numerous different immune-related cutaneous adverse events (irCAEs). Beyond impacting quality of life, irCAEs can lead to dose limitations or discontinuation of anti-cancer therapies. Correct diagnosis is necessary for expedient and appropriate management. Skin biopsies are often performed to increase diagnostic accuracy and guide clinical management. An extensive literature review was performed using the PubMed database to identify the reported clinical and histopathologic features of irCAEs. This comprehensive review primarily details the histopathologic features of various irCAEs reported to date. Clinical presentation and immunopathogenesis are also discussed in relation to histopathology.

Pemphigus vulgaris as an immune-related adverse event in recurrent metastatic esophageal squamous cell carcinoma treated with ipilimumab plus nivolumab: a case report and literature review

Ipilimumab plus nivolumab therapy is approved for patients with unresectable advanced esophageal squamous cell carcinoma (ESCC). Although a combination of immune checkpoint inhibitors (ICIs), compared to conventional chemotherapy, can improve overall survival in patients with advanced ESCC, this increases the incidence of immune-related adverse events (irAEs). Here, we describe an ESCC case that developed pemphigus vulgaris (PV), an extremely rare cutaneous irAE, during ipilimumab plus nivolumab treatment. The patient achieved a partial response to treatment. The PV was successfully managed after the cessation of ipilimumab and the use of a topical steroid. We should thus re-treat ESCC with nivolumab monotherapy. In the era of ICIs as standard cancer therapeutics, diagnostic criteria for blistering diseases need to be established to properly manage patients with cutaneous irAEs.

Autoimmune bullous dermatoses in cancer patients treated by immunotherapy: a literature review and Italian multicentric experience

Cutaneous immune-related adverse events are frequently associated with immune checkpoint inhibitors (ICIs) administration in cancer patients. In fact, these monoclonal antibodies bind the cytotoxic T-lymphocyte antigen-4 and programmed cell death-1/ligand 1 leading to a non-specific activation of the immune system against both tumoral cells and self-antigens. The skin is the most frequently affected organ system appearing involved especially by inflammatory manifestations such as maculopapular, lichenoid, psoriatic, and eczematous eruptions. Although less common, ICI-induced autoimmune blistering diseases have also been reported, with an estimated overall incidence of less than 5%. Bullous pemphigoid-like eruption is the predominant phenotype, while lichen planus pemphigoides, pemphigus vulgaris, and mucous membrane pemphigoid have been described anecdotally. Overall, they have a wide range of clinical presentations and often overlap with each other leading to a delayed diagnosis. Achieving adequate control of skin toxicity in these cases often requires immunosuppressive systemic therapies and/or interruption of ICI treatment, presenting a therapeutic challenge in the context of cancer management. In this study, we present a case series from Italy based on a multicenter, retrospective, observational study, which included 45 patients treated with ICIs who developed ICI-induced bullous pemphigoid. In addition, we performed a comprehensive review to identify the cases reported in the literature on ICI-induced autoimmune bullous diseases. Several theories seeking their underlying pathogenesis have been reported and this work aims to better understand what is known so far on this issue.

Cutaneous Side Effects of Modern Targeted Therapy and Immunotherapy in Patients with Dermatological Malignancies

The advent of immunotherapy and targeted therapies in treating dermatological malignancies has dramatically changed the landscape of dermato-oncology in recent years. Their superior efficacy compared to previous therapeutic options, such as chemotherapy, has resulted in their use in treating devastating malignancies, such as melanoma or unresectable/metastatic basal cell and squamous cell carcinoma. Skin toxicity is a critical safety consideration, among other adverse reactions, that can occur under treatment with these agents. This article aims to summarize the cutaneous side effects of immune checkpoint inhibitors and targeted dermato-oncological therapies. Although the skin side effects of these agents are primarily mild, they can occasionally affect the decision for treatment continuation and the quality of life of the affected patients. Therefore, physicians must be acquainted with the specific cutaneous toxicity profile of such treatments to mitigate their impact on the patients and optimize the overall outcome of dermato-oncological therapy.

Autoimmune Pemphigus: Latest Advances and Emerging Therapies

Pemphigus represents a group of rare and severe autoimmune intra-epidermal blistering diseases affecting the skin and mucous membranes. These painful and debilitating diseases are driven by the production of autoantibodies that are mainly directed against the desmosomal adhesion proteins, desmoglein 3 (Dsg3) and desmoglein 1 (Dsg1). The search to define underlying triggers for anti-Dsg-antibody production has revealed genetic, environmental, and possible vaccine-driven factors, but our knowledge of the processes underlying disease initiation and pathology remains incomplete. Recent studies point to an important role of T cells in supporting auto-antibody production; yet the involvement of the myeloid compartment remains unexplored. Clinical management of pemphigus is beginning to move away from broad-spectrum immunosuppression and towards B-cell-targeted therapies, which reduce many patients’ symptoms but can have significant side effects. Here, we review the latest developments in our understanding of the predisposing factors/conditions of pemphigus, the underlying pathogenic mechanisms, and new and emerging therapies to treat these devastating diseases.

Oral Immune-Related Adverse Events Caused by Immune Checkpoint Inhibitors: Salivary Gland Dysfunction and Mucosal Diseases

Conventional chemotherapy and targeted therapies have limited efficacy against advanced head and neck squamous cell carcinoma (HNSCC). The immune checkpoint inhibitors (ICIs) such as antibodies against CTLA-4, PD-1, and PD-L1 interrupt the co-inhibitory pathway of T cells and enhance the ability of CD8+ T cells to destroy tumors. Even in advanced HNSCC patients with recurrent diseases and distant metastasis, ICI therapy shows efficiency and become an effective alternative to conventional chemotherapy. However, as this therapy releases the immune tolerance state, cytotoxic CD8+ T cells can also attack organs and tissues expressing self-antigens that cross-react with tumor antigens and induce immune-related adverse events (irAEs). When patients with HNSCC are treated with ICIs, autoimmune diseases occur in multiple organs including the skin, digestive tract, endocrine system, liver, and respiratory tract. Treatment of various malignancies, including HNSCC, with ICIs may result in the appearance of oral irAEs. In the oral cavity, an oral lichenoid reaction (OLR) and pemphigoid develop. Sicca syndrome also occurs in association with ICIs, affecting the salivary glands to induce xerostomia. It is necessary to elucidate the pathogenic mechanisms of these intractable diseases that are not seen with conventional therapy. Early diagnosis and appropriate approaches to irAEs are needed for efficient treatment of advanced HNSCC by ICIs.

Promising Natural Products in New Drug Design, Development, and Therapy for Skin Disorders: An Overview of Scientific Evidence and Understanding Their Mechanism of Action

The skin is the largest organ in the human body, composed of the epidermis and the dermis. It provides protection and acts as a barrier against external menaces like allergens, chemicals, systemic toxicity, and infectious organisms. Skin disorders like cancer, dermatitis, psoriasis, wounds, skin aging, acne, and skin infection occur frequently and can impact human life. According to a growing body of evidence, several studies have reported that natural products have the potential for treating skin disorders. Building on this information, this review provides brief information about the action of the most important in vitro and in vivo research on the use of ten selected natural products in inflammatory, neoplastic, and infectious skin disorders and their mechanisms that have been reported to date. The related studies and articles were searched from several databases, including PubMed, Google, Google Scholar, and ScienceDirect. Ten natural products that have been reported widely on skin disorders were reviewed in this study, with most showing anti-inflammatory, antioxidant, anti-microbial, and anti-cancer effects as the main therapeutic actions. Overall, most of the natural products reported in this review can reduce and suppress inflammatory markers, like tumor necrosis factor-alpha (TNF-α), scavenge reactive oxygen species (ROS), induce cancer cell death through apoptosis, and prevent bacteria, fungal, and virus infections indicating their potentials. This review also highlighted the challenges and opportunities of natural products in transdermal/topical delivery systems and their safety considerations for skin disorders. Our findings indicated that natural products might be a low-cost, well-tolerated, and safe treatment for skin diseases. However, a larger number of clinical trials are required to validate these findings. Natural products in combination with modern drugs, as well as the development of novel delivery mechanisms, represent a very promising area for future drug discovery of these natural leads against skin disorders.

Drug eruptions with novel targeted therapies - immune checkpoint and EGFR inhibitors

Given the increasing use of novel targeted therapies, dermatologists are constantly confronted with novel cutaneous side effects of these agents. A rapid diagnosis and appropriate management of these side effects are crucial to prevent impairment of the patients' quality of life and interruptions of essential cancer treatments. Immune checkpoint and EGFR inhibitors are frequently used targeted therapies for various malignancies and are associated with a distinct spectrum of cutaneous adverse events. Exanthematous drug eruptions represent a particular diagnostic challenge in these patients. Immune checkpoint inhibitors can elicit a plethora of immune-related exanthemas, most commonly maculopapular, lichenoid, and psoriasiform eruptions. Additionally, autoimmune bullous dermatoses and exanthemas associated with connective tissue diseases may arise. In cases of severe, atypical or therapy-resistant presentations an extensive dermatological investigation including a skin biopsy is recommended. Topical and systemic steroids are the mainstay of treatment. Papulopustular eruptions represent the major cutaneous adverse effect of EGFR inhibitor therapy, occurring in up to 90 % of patients within the first two weeks of therapy, depending on the agent. Besides topical antibiotics and steroids, oral tetracyclines are the first choice in systemic treatment and can also be used as prophylaxis.

Management of Cutaneous Immune-Related Adverse Events in Patients With Cancer Treated With Immune Checkpoint Inhibitors: A Systematic Review

Importance

There exists a paucity of literature that summarizes the effective management of cutaneous immune-related adverse events (cirAEs) in patients with cancer who are receiving immune checkpoint inhibitors (ICIs). Most published articles are small case series from a single institution. To our knowledge, the spectrum of possible treatments has not been systematically reviewed to highlight the breadth of options when caring for patients with cirAEs.

Objective

To further characterize the development of subtypes of cirAEs in patients with cancer treated with ICIs and provide recommendations on optimal treatment regimens based on the current literature.

Evidence Review

A search was performed in PubMed, Embase European, Web of Science, and Google Scholar on June 26, 2020, according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines, limited to the years 2010 to 2020. Articles that met predetermined inclusion criteria (published between January 1, 2010, and June 1, 2020; written in the English language; and original articles, brief reports, case reports, and research letters that reported primarily on cirAE management) were selected, and data were abstracted. Articles that met the scope of the review were also added from reference lists. When possible, the results of studies that addressed a similar question were combined quantitatively.

Findings

In total, 138 studies (87 from the aforementioned literature search and 51 additional studies pulled from the reference lists of included articles) were included that reported on 879 cirAEs. The subtypes of cirAEs included maculopapular, pruritus, lichenoid, immunobullous, psoriasiform, granulomatous, erythema multiforme or Stevens Johnson Syndrome, drug rash with eosinophilia and systemic symptoms, connective tissue disease, hair, oral, and miscellaneous. Treatments for cirAEs included a combination of topical corticosteroids, systemic corticosteroids, steroid-sparing agents, and discontinuation or cessation of immunotherapy.

Conclusions and Relevance

This systematic review found that treatment with ICIs was associated with many types of skin toxic effects, each with unique treatment options beyond current published guidelines. Further research into key differences between subtypes is critical to improve the care provided to patients with cancer.

Pemphigus Herpetiformis-Type Drug Reaction Caused by Programmed Cell Death Protein-1 Inhibitor Treatment

Reports of immune-related adverse events caused by programmed cell death protein-1 inhibitor are becoming increasingly frequent. Herein, we report the first case of pemphigus herpetiformis-type drug reaction presented after the treatment of tislelizumab (6 cycles) in a primary non-small cell lung carcinoma patient. A 56-year-old Chinese man was referred to our department for pruritic annulare erythema and blister for two weeks. Histological finding revealed blister formation in the epidermis and eosinophilic infiltration in the blister fluid. Direct immunofluorescence showed intercellular deposition of IgG and C3 within the lower part of epidermis. Serum anti-intercellular antibodies were positive at 1:100 dilution. Based on history and clinicopathological correlation, herpetiformis-type drug-induced pemphigus was diagnosed, which was possibly be induced by tislelizumab. To the best to our knowledge, there is no report of pemphigus herpetiformis-type drug-induced reaction associated with programmed cell death protein-1 inhibitor treatment.

Case Report: Autoimmune Pemphigus Vulgaris in a Patient Treated With Cemiplimab for Multiple Locally Advanced Cutaneous Squamous Cell Carcinoma

BACKGROUND

Pemphigus vulgaris (PV) is a rare and severe autoimmune blistering disorder affecting the skin and mucous membranes, characterized by the production of autoantibodies against two desmosomal adhesion proteins, desmoglein 1 and 3. In patients with advanced squamous cell carcinoma of the skin unfit for surgery and radiotherapy, immune check-point inhibitors, including the anti-Programmed Death-1 (PD-1) agent cemiplimab have been successfully employed proving relevant clinical outcomes. Cemiplimab is a monoclonal antibody capable of inhibiting PD-1 signalling that has recently been approved for the treatment of patients with metastatic or locally advanced cutaneous squamous cell carcinoma. Although the peculiar setting of advanced CSCC involving elderly patients, rare and unusual skin immune-related adverse events such as PV could be observed in cemiplimab treated patients.

CASE REPORT

A 95-year-old man without a history of autoimmune disease was treated with cemiplimab for multiple and advanced squamous cell carcinomas of the head obtaining a complete response to therapy. After seven cycles of cemiplimab administered every 21 days, the patient developed a mucocutaneous blistering eruption. Clinical diagnosis of PV was suspected on the basis of the diffuse involvement of trunk and extremities with large blisters and necrotic eschar. It was carried out an ELISA test, that showed high level of circulating antibodies against desmoglein 1, thus confirming the diagnosis of PV. For this reason, cemiplimab infusion was discontinued and complete resolution of skin lesions was obtained using oral prednisone 0,8 mg/kg/daily for four weeks. Once remission was achieved, a maintenance dose of 10 mg/day was administered, observing a good control of bullous disease and low value of desmoglein 1. Response to CSCC persisted also during cemiplimab discontinuation, until obtaining a complete remission still persisting at 9 months after the last cycle of therapy.

CONCLUSION

The case we observed is the first description of PV revealed from cemiplimab therapy, thus suggesting that cemiplimab could allow the arise of underlying autoimmune PV, through a mechanism both T and B-cell-mediated.

Cutaneous adverse events caused by immune checkpoint inhibitors

IMPORTANCE

Immune checkpoint inhibitors (ICIs) have emerged as active therapies for a variety of cancers. Cutaneous toxicities are common immune-related adverse events and patients will often be referred to dermatologists for evaluation.

OBSERVATIONS

Cutaneous adverse events to ICIs can have a variety of clinical presentations. Among the more common are eczematous, morbilliform, and lichenoid dermatoses, as well as vitiligo and pruritus. Less common adverse events include psoriasiform dermatoses, bullous disorders, and severe cutaneous adverse reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms. Because of the immunologic mechanism of ICIs, there are also a variety of rheumatologic adverse reactions with cutaneous manifestations, such as scleroderma, dermatomyositis, cutaneous lupus erythematosus, and various vasculitides. These cutaneous reactions often respond to topical or systemic steroids, although specific toxicities may have alternative treatments available.

CONCLUSIONS AND RELEVANCE

As they become more widely prescribed, dermatologists will see an increasing number of patients with cutaneous adverse events caused by ICI therapies. Accurately diagnosing and treating these toxicities is paramount to achieving the most favorable outcomes for patients.

Squamous cell carcinoma arising within hidradenitis suppurativa: a literature review

Squamous cell carcinoma (SCC) can present as a rare complication of longstanding hidradenitis suppurativa (HS) lesions. Limited data exist on characteristics and outcomes of SCC development within HS lesions. The purpose of this review is to conduct a literature review of previously reported cases of SCC development in pre-existing HS lesions. EMBASE and MEDLINE searches were conducted in OVID on June 25, 2020, to yield 59 studies. Of the 95 patients (mean age: 52.9 years) who developed a total of 122 SCCs within HS lesions, the majority were males (77.9%, n = 74/95). The most common sites of SCC were the gluteal region (47.5%, n = 58/122), the perianal region (18.9%, n = 23/122), and the genitals (13.9%, n = 17/122). The mean duration between HS onset and SCC development was 25.5 years. Of the patients that had outcomes reported, 54.0% (n = 34/63) experienced SCC metastasis, 43.1% (n = 28/65) experienced SCC recurrences, and 58.7% (n = 44/75) experienced a mortality outcome. The most common documented reasons for death included metastasis (34.1%, n = 15/44) and sepsis (13.6%, n = 6/44). Patients with longstanding HS lesions can develop SCCs with a high rate of metastasis and mortality. Thus, chronic HS lesions, especially in the gluteal, perianal, genital, and perineal regions, should be monitored regularly for timely SCC diagnosis and management.

Cutaneous Squamous Cell Carcinoma in Patients with Hidradenitis Suppurativa

Background: Cutaneous squamous cell carcinoma (cSCC) is a rare complication of hidradenitis suppurativa (HS). Objectives: To conduct a systematic review and an individual patient data (IPD) meta-analysis to describe the clinical characteristics of HS patients developing cSCC and determine predictors of poor outcome. Methods: Medline/PubMed, Embase, and Web of Science were searched for studies reporting cSCC arising in patients with HS from inception to December 2019. A routine descriptive analysis, statistical hypothesis testing, and Kaplan-Meier survival curves/Cox proportional hazards regression models were performed. Results: A total of 34 case reports and series including 138 patients were included in the study. The majority of patients were males (81.6%), White (83.3%), and smokers (n = 22/27 reported) with a mean age of 53.5 years. Most patients had gluteal (87.8%), Hurley stage 3 HS (88.6%). The mean time from the diagnosis of HS to the development of cSCC was 24.7 years. Human papillomavirus was identified in 12/38 patients tested. Almost 50% of individuals had nodal metastasis and 31.3% had distant metastases. Half of the patients succumbed to their disease. Conclusions: cSCC is a rare but life-threatening complication seen in HS patients, mainly occurring in White males who are smokers with severe, long-standing gluteal HS. Regular clinical examination and biopsy of any suspicious lesions in high-risk patients should be considered. The use of HPV vaccination as a preventive and possibly curative method needs to be explored.