Paraneoplastic Pemphigus and Autoimmune Blistering Diseases Associated with Neoplasm: Characteristics, Diagnosis, Associated Neoplasms, Proposed Pathogenesis, Treatment

S2k guidelines on diagnosis and treatment of linear IgA dermatosis initiated by the European Academy of Dermatology and Venereology

INTRODUCTION

Linear IgA dermatosis (LAD) is a rare subepidermal autoimmune bullous disease (AIBD) defined by predominant or exclusive immune deposits of immunoglobulin A at the basement membrane zone of skin or mucous membranes. This disorder is a rare, clinically and immunologically heterogeneous disease occurring both in children and in adults. The aim of this project is to present the main clinical features of LAD, to propose a diagnostic algorithm and provide management guidelines based primarily on experts' opinion because of the lack of large methodologically sound clinical studies.

METHODS

These guidelines were initiated by the European Academy of Dermatology and Venereology (EADV) Task Force Autoimmune Bullous Diseases (AIBD). To achieve a broad consensus for these S2k consensus-based guidelines, a total of 29 experts from different countries, both European and non-European, including dermatologists, paediatric dermatologists and paediatricians were invited. All members of the guidelines committee agreed to develop consensus-based (S2k) guidelines. Prior to a first virtual consensus meeting, each of the invited authors elaborated a section of the present guidelines focusing on a selected topic, based on the relevant literature. All drafts were circulated among members of the writing group, and recommendations were discussed and voted during two hybrid consensus meetings.

RESULTS

The guidelines summarizes evidence-based and expert opinion-based recommendations (S2 level) on the diagnosis and treatment of LAD.

CONCLUSION

These guidelines will support dermatologists to improve their knowledge on the diagnosis and management of LAD.

[Paraneoplastic pemphigus with underlying Castleman's disease in a 16-year-old girl]

Paraneoplastic pemphigus is a rare, life-threatening autoimmune disease that is clinically characterized by mostly extensive and refractory mucosal erosions and polymorphous skin lesions. We report here on a 16-year-old girl with isolated oral erosions, in whom mucosal pemphigoid was initially suspected and after treatment with prednisolone and dapsone marked improvement was achieved. However, a few months later the patient developed massive respiratory insufficiency as a result of bronchiolitis obliterans, so that a lung transplant was planned. As part of the preparatory diagnostic workup, unicentric, abdominally localized Castleman's disease was diagnosed, which ultimately led to the diagnosis of paraneoplastic pemphigus as evidenced by envoplakin autoantibodies. Tumor resection and subsequent lung transplantation achieved good results with sustained mucocutaneous remission.

Case Report: The many faces of bullous pemphigoid

The pemphigoid group comprises a number of bullous skin diseases with autoantibodies against different constituents of the basement membrane zone that result in subepidermal detachment and clinically characteristic tense blisters, erosions, urticarial erythema, and itching. Apart from the most frequent type of bullous pemphigoid with antibodies against BP180, which is found predominantly in elderly patients, the disease may present at other ages and different pathogenic conditions. Here, four cases are presented of young age (3 months and 25, 34, and 46 years) and in association with vaccination, pregnancy, or metastatic cancer. Though anti-BP180 was found in all cases, a different pathogenic background may be found in any of them, resulting in characteristic clinical manifestation, yet demanding specifically adapted therapeutic approaches.

Ocular involvement in autoimmune bullous diseases

Autoimmune bullous diseases represent a heterogenous group of disorders caused by autoantibodies against adhesion molecules; the location of the target protein determines the level of cleft formation. The spectrum of ocular lesions in autoimmune bullous diseases can range from mild symptoms to severe involvement with sight impairment and even, in some cases, blindness. In pemphigus vulgaris, the prevalence of ocular involvement has been reported to be between 7% and 26%. The most common clinical sign of ocular pemphigus vulgaris is bilateral conjunctivitis with hyperemia. Ocular involvement also occurs in 41% to 70% of patients with paraneoplastic pemphigus. The main ocular manifestations are bilateral cicatrizing conjunctivitis with symblepharon formation, and shortening of the fornices. In mucous membrane pemphigoid, ocular involvement is seen in 61% to 70% of patients; the most frequent ocular finding is cicatricial conjunctivitis. Patients with autoimmune bullous diseases having common ocular involvement should be assessed by an ophthalmologist to avoid serious complications. Diagnostic procedures and treatment require multidisciplinary care based on the close cooperation between dermatologists and ophthalmologists.

Dermatological manifestations of hematologic neoplasms. Part II: nonspecific skin lesions/paraneoplastic diseases

Cutaneous manifestations occur in the course of hematologic malignancies and precede, accompany or occur late in relation to the diagnosis. They result from paraneoplastic phenomena, tumor infiltrations, immunosuppression resulting from the hematologic disease itself or its treatment. The dermatologist must be aware of these conditions that may be helpful both in the diagnosis of the underlying disease and in reducing patient morbidity. This review (part II) addresses the paraneoplastic dermatological changes associated with systemic hematologic malignancies.

Oral presentation of paraneoplastic pemphigus as the first sign of tonsillar HPV associated squamous cell carcinoma. A case report

BACKGROUND

Paraneoplastic pemphigus (PNP) in the oral cavity is a rare variant of blistering pemphigus disease closely associated with mostly malignant tumors. The diagnosis may even precede an underlying malignancy enabling early detection. Here, we describe a previously unreported case of PNP associated with HPV-related tonsillar squamous cell carcinoma.

METHODS AND RESULTS

A 50-year-old woman was referred to a dentist because of painful oral lesions resembling aphthae major and minor. Later, blisters appeared and an incisional biopsy was performed. Histological examination revealed an unusual coexistence of subepithelial and intraepithelial blisters raising suspicion of paraneoplastic pemphigus. The patient underwent 18F-FDG PET/MRI, showing a metabolically active process in the left palatal tonsil. Diagnostic biopsy revealed HPV type 16 associated tonsillar squamous cell carcinoma. A left tonsillectomy with elective left-sided neck dissection was performed. The postoperative period was complicated by bilateral fluidothorax. Two weeks after radical tumor removal, the mucosal and skin lesions of PNP disappeared. The patient currently shows no evidence of recurrence either of malignancy or PNP eight months after the surgery.

CONCLUSION

PNP is a rare autoimmune blistering disease characterized by polymorphous cutaneous and mucosal lesions associated with internal neoplasms including HPV associated squamous cell carcinoma of a tonsil. In order to identify an occult malignancy, a whole-body PET/CT or PET/MRI scan is recommended. Rarely, accurate patient management may depend on the dentist being familiar with this entity and on interdisciplinary cooperation involving dermatologist, radiologist, pathologist, and pneumologist. A strict patient follow-up is indicated.

Pharyngeal-Esophageal Malignancies with Dermatologic Paraneoplastic Syndrome

Systemic changes often send signals to the skin, and certain neoplastic diseases of the internal organs can also trigger skin manifestations. In this article, the authors make clinical photography presentations of the patients seen at our clinic with dermatologic paraneoplastic syndromes within pharyngeal–esophageal malignancies, describe several paraneoplastic dermatoses, and also review high-quality scientific literature in order to be able to highlight the dermatological signs of pharyngoesophageal malignant tumors. The majority of our patients with paraneoplastic dermatoses, filtering for pharyngoesophageal malignancies, had esophageal neoplasms, out of whom seven were female and two were male, making esophageal cancer more common within the paraneoplastic dermatoses within pharyngoesophageal malignancies. An early recognition of paraneoplastic dermatoses can diagnose neoplasms and sequentially contribute to a better prognosis for the patient. This matter is also useful for front-line medical personnel in order to improve early diagnosis of the underlying malignancy, curative interventions with prompt therapy administration and good prognosis.

Indirect immunofluorescence on rat bladder epithelium in patients with pemphigus vulgaris with an extended follow‐up

Background

Indirect immunofluorescence (IIF) on rat bladder epithelium (RBE) has been widely used to detect anti‐plakin antibodies present in paraneoplastic pemphigus (PNP). However, anti‐plakin antibodies have also been found in a group of patients with pemphigus vulgaris (PV).

Objectives

To assess the reactivity rate of PV sera in IIF using RBE as substrate and the diagnostic usefulness of the aforementioned test.

Methods

Patients diagnosed with PV presenting to Razi Hospital, Tehran, Iran, were recruited. The patients' demographics, disease severity, and response to the initial treatment were recorded. Sera were collected and tested by IIF on RBE and by desmoglein 3/1 (Dsg 3/1) enzyme‐linked immunosorbent assay. Patients were followed up closely for a mean of 53.9 months for any evidence of malignancy.

Results

Forty‐six patients were enroled (mean age of 42.9 years old, 31 females). Nine sera (19.6%) showed reactivity in IIF on RBE. Mean serum anti‐Dsg levels did not differ significantly among the two groups with positive and negative IIF results. Negative anti‐Dsg3 was related to a higher positive rate in IIF on RBE. There was no significant correlation between the reactivity of IIF on RBE and patients' demographic, clinical, or serological characteristics.

Conclusions

IIF on RBE is a sensitive test for detecting antibodies against plakins. However, it has a relatively high false‐positive rate in PV, probably due to the epitope spreading phenomenon. This test should be suggested when there is a clinical or immunohistopathological suspicion of PNP and should be interpreted with caution.

Linear IGA bullous dermatosis potentially triggered by vaccination

Linear IgA bullous dermatosis (LABD) is a mucocutaneous autoimmune blistering disease affecting both adults and children. It is caused by IgA antibodies targeting multiple antigens along the basement membrane zone, leading to disruption of dermoepidermal junction and development of bullous lesions which often presents in characteristic arrangement. Although most LABD cases have been reported to be idiopathic, different triggers have been described, including several drugs and infection. However, the occurrence of vaccine-induced cases of LABD is not widely known and accepted due to the few reports available. We present two cases of LABD occurred following different triggers, rising the suspicion for a possible pathogenetic role of vaccines.

Paraneoplastic pemphigus associated with post-transplant lymphoproliferative disorder after small bowel transplantation

BACKGROUND

PNP is a malignancy-associated autoimmune mucocutaneous syndrome due to autoantibodies against plakins, desmogleins, and other components of the epidermis and basement membrane of epithelial tissues. PNP-causing malignancies comprise mainly lymphoproliferative and hematologic neoplasms. PNP is extremely rare, especially in children.

METHODS

Here, we present the first case of a child who developed PNP on a PTLD after small bowel transplantation because of a severe genetic protein-losing enteropathy.

RESULTS

The patient in this case report had a severe stomatitis, striate palmoplantar keratoderma, and lichenoid skin lesions. In addition, she had marked esophageal involvement. She had lung pathology due to recurrent pulmonary infections and ventilator injury. Although we found no evidence of BO, she died from severe pneumonia and respiratory failure at the age of 12 years.

CONCLUSION

It is exceptional that, despite effective treatment of the PTLD, the girl survived 5 years after her diagnosis of PNP. We hypothesize that the girl survived relatively long after the PNP diagnosis due to strong T-cell suppressive treatments for her small bowel transplantation.

Risk Factors for Mucosal Involvement in Bullous Pemphigoid and the Possible Mechanism: A Review

Bullous pemphigoid (BP) is the most common type of autoimmune bullous disease and is characterized by the presence of circulating anti-BP180 and/or anti-BP230 autoantibodies. Patients with BP often present with tense blisters and erythema, mainly on the trunk and limbs, but a few patients also have mucosal involvement. In this article, we discuss the fact that BP patients with mucosal involvement tend to have more serious conditions and their disease is more difficult to control. Potential risk factors for mucous involvement include earlier age at onset, drugs such as dipeptidyl peptidase-4 inhibitors, cancer, and blood/serum biomarkers, including lower eosinophil count, higher erythrocyte sedimentation rate, IgG autoantibodies against both the NH₂- and COOH-termini of BP180, and the absence of anti-BP230 antibodies. IgA and C3 deposition at the dermo-epidermal junction may also be present. Understanding these risk factors may benefit earlier diagnosis of these patients and promote the development of novel treatments. What's more, it's helpful in deeper understanding of BP development and the relationship between BP and mucous membrane pemphigoid (MMP).

Clinical characteristics and immunological abnormalities of Castleman disease complicated with autoimmune diseases

Purpose

To explore the clinical features and immunological mechanisms of Castleman disease (CD) complicated with autoimmune diseases (AID).

Methods

We explored the prevalence and clinical manifestations of CD complicated with AID by reviewing clinical, pathological, and laboratory data of 40 CD patients retrospectively, and then explored abnormal immune mechanisms in the co-existence of the two entities by monitoring lymphocyte subsets in peripheral blood.

Results

Paraneoplastic pemphigus, autoimmune hemolytic anemia, Sjogren’s syndrome, myasthenia gravis, and psoriasis were found to be coexisted with CD in 9/40 (22.5%) patients with different sequence of onset. No bias in the clinical and histological type of CD was observed for the occurrence of AID. CD patients with AID were more likely to have skin and/or mucous membrane damage and pulmonary complications, and presented elevated erythrocyte sedimentation rate, hypergammaglobulinemia, and positive autoantibodies than those without AID (p < 0.05). Deregulated cellular and innate immune responses as indicated by decreased CD3⁺ T cells and increased natural killer cells were observed in peripheral blood of CD patients with AID (p < 0.05). UCD patients with AID were successfully treated with surgery and immunosuppressive therapy. MCD complicated by AID relieved with immunosuppressors, cytotoxic chemotherapy, and rituximab.

Conclusion

Systemic inflammation/immunological abnormalities and organ dysfunction were associated with the occurrence of AID in CD. Impairment of cellular and innate immunity may be a candidate etiology for the coexistence of the two entities.

Linear IGA-dependent bullous dermatosis in a 2-year-old child

Linear IgA-dependent bullous dermatosis is a rare subepidermal bladderworm disease that occurs in both adults and children. The pathogenesis of the disease, regardless of age, is the same, where the basis is the autoimmune response to antigens of the basal membrane zones of the skin, the clinical picture in childhood differs from the manifestations at an older age, having a clear picture and localization of manifestations. The causes of the onset of the disease in older people are most often associated with taking medications, manifested as a side effect of the therapy being taken, cancer, and in children, both an acquired character and a genetic predisposition are responsible for the manifestation of linear IgA-dependent bullous dermatosis. The diagnosis can be confirmed by histological and immunofluorescence analysis.

Multidisciplinary diagnosis and treatment of recurrent follicular dendritic cell sarcoma in abdomen: A case report

RATIONALE

Follicular dendritic cell sarcoma (FDCS) is a rare malignant tumor derived from follicular dendritic cells, and is often associated with Castleman disease. Here we present a rare case of paraneoplastic pemphigus (PNP) with FDCS which required multidisciplinary approach for the diagnosis and treatment.

PATIENT CONCERNS

A 28-year-old Chinese female had FDCS recurrence, and primary clinical manifestation was PNP.

DIAGNOSES

PNP with FDCS.

INTERVENTIONS

The patient received gamma globulin infusion, took anlotinib, and underwent plasma exchange therapy.

OUTCOMES

The skin lesions recovered and there was no evidence of tumor recurrence.

LESSONS

The diagnosis and management of PNP with FDCS require close cooperation among surgeons, dermatologists, hematologists, otolaryngologists, oncologists, radiologists, pathologists, and respiratory doctors. The interesting clinical manifestations of this patient provide a multifaceted approach to the investigation of the interactions among FDCS, Castleman disease, and PNP.

Dermatological Manifestations in the Intensive Care Unit: A Practical Approach

Dermatological problems are not usually related to intensive medicine because they are considered to have a low impact on the evolution of critical patients. Despite this, dermatological manifestations (DMs) are relatively frequent in critically ill patients. In rare cases, DMs will be the main diagnosis and will require intensive treatment due to acute skin failure. In contrast, DMs can be a reflection of underlying systemic diseases, and their identification may be key to their diagnosis. On other occasions, DMs are lesions that appear in the evolution of critical patients and are due to factors derived from the stay or intensive treatment. Lastly, DMs can accompany patients and must be taken into account in the comprehensive pathology management. Several factors must be considered when addressing DMs: on the one hand, the moment of appearance, morphology, location, and associated treatment and, on the other hand, aetiopathogenesis and classification of the cutaneous lesion. DMs can be classified into 4 groups: life-threatening DMs (uncommon but compromise the patient's life); DMs associated with systemic diseases where skin lesions accompany the pathology that requires admission to the intensive care unit (ICU); DMs secondary to the management of the critical patient that considers the cutaneous manifestations that appear in the evolution mainly of infectious or allergic origin; and DMs previously present in the patient and unrelated to the critical process. This review provides a characterization of DMs in ICU patients to establish a better identification and classification and to understand their interrelation with critical illnesses.

Paraneoplastic bullous pemphigoid - A sign of clear cell renal carcinoma

Paraneoplastic bullous pemphigoid is a rare paraneoplastic syndrome. Rash is pruritic, with erythematous eruption of large subepidermal bullae over skin and often mucosal surfaces. We present an 84y woman with a three week history of erythematous rash, and 48hrs of bullae. A left clear cell renal cell carcinoma was identified on CT imaging during the presentation. Subsequent removal of the tumour resulted in resolution of bullous pemphigoid symptoms. This first-of-kind case and successful result strengthens the association between renal cell carcinoma and paraneoplastic bullous pemphigoid, arguing for a high degree of clinical suspicion in unexplained presentations of bullous pemphigoid.

Exfoliative Erythroderma: An Unusual Presentation of Paraneoplastic Pemphigus Associated with Castleman's Disease

We report a 23-year-old woman who presented with generalized scaly erythematous rash predominately on the upper trunk and hemorrhagic stomatitis. The histopathologic and immunopathologic findings were consistent with the diagnosis of paraneoplastic pemphigus. Castleman's tumor was diagnosed with computed tomography and exploratory laparotomy. A partial clinical improvement was observed after complete tumor removal and intravenous immunoglobulin administration. However, the patient died as a result of septicemia.

Linear IgA dermatosis in association with angioimmunoblastic T-cell lymphoma infiltrating the skin: A case report with literature review

Angioimmunoblastic T-cell lymphoma (AITL) is an aggressive form of peripheral T-cell lymphoma, characterized by systemic symptoms, diffuse lymphadenopathy, hepatosplenomegaly and immunodysregulation. Half of AITL is associated with cutaneous symptoms, but only few cases with bullous eruption have been described. Association with a linear IgA dermatosis is extremely rare. Linear IgA dermatosis can be idiopathic, or linked with drug intake or neoplastic disorders. Some cases of linear IgA dermatosis presenting as toxic epidermal necrolysis (TEN) have been described, most of them being drug induced. We here present the case of a 72-year-old man recently diagnosed with AITL who developed a bullous eruption, presenting as TEN. Histopathology showed deep cutaneous involvement of the lymphoma with a sub-epidermal blistering and direct immunofluorescence revealed a heavy IgA linear deposit on the dermal-epidermal junction. A diagnosis of linear IgA dermatosis associated with cutaneous involvement of an angioimmunoblastic T-cell lymphoma was made. Chemotherapy and corticosteroids allowed cutaneous improvement but the patient died of his lymphoma shortly after.

Dermatomyositis in patients with autoimmune blistering diseases

It is common for multiple autoimmune diseases to occur in the same patient. However, autoimmune blistering diseases (AIBD) do not commonly associate with dermatomyositis (DM). We performed a literature review and found 12 previous reports that may be attributed to misdiagnosis, underreporting, or true rarity of association. Herein, we present a case of pemphigus vulgaris and a case of mucous membrane pemphigoid associated with DM and review the related literature. AIBD-associated interstitial lung disease, genetic predisposition, potential environmental triggers of both AIBD and DM, drug-related triggers, and paraneoplastic processes are discussed. Dermatologists must be vigilant for a second autoimmune disease in patients with AIBD that may have therapeutic implications.

Linear IgA bullous dermatosis in adults and children: a clinical and immunopathological study of 38 patients

BACKGROUND

Linear IgA bullous dermatosis (LABD) is a rare autoimmune subepithelial vesiculobullous disease due to IgA autoantibodies directed against different antigens of the basement membrane zone (BMZ) of the skin and/or mucosae. It affects mainly preschool-aged children and adults, with only few studies on large series. The aim of this study was to assess possible differences between adults and children regarding clinical presentation, immunopathologic features, management and course of the disease.

METHODS

A retrospective review of 38 LABD patients, followed-up from November 2006 to September 2018, was performed.

RESULTS

Of 38 patients, 27 were adults and 11 children. Mean age at diagnosis was 5.4 years and 60.6 years in the pediatric and adult group, respectively. Considering both groups, limbs were the most commonly involved site (73.7%), followed by trunk (55.3%), head (36.8%) and buttocks (13.2%). Interestingly, head (p = 0.008), particularly perioral (p = 0.001), involvement, as well as "string of pearls" arrangement (p = 0.03), were more prevalent in children. Mucosal involvement was seen in 9 (23.7%) patients and was more frequent in children than adults (45.5% vs 14.8%, respectively, p = 0.09). Linear IgA deposits along the BMZ were observed in 30 patients (78.9%), while linear/granular IgA deposits in 8 patients (21.1%). Dapsone was the most commonly used drug (78.9%) and complete remission was achieved in most cases (81.6%).

CONCLUSIONS

Our epidemiological and clinicopathological findings relative to a large cohort of LABD patients are mostly consistent with the literature data. Interestingly, head, notably perioral, involvement and "string of pearls" arrangement occurred more frequently in the paediatric than adult group. The above clinical parameters may be regarded as diagnostic tools for LABD in children.

Mucous Membrane Pemphigoid-Associated Malignancies: Case Series and a Brief Overview of the Literature

Background

Mucous membrane pemphigoid (MMP) is a heterogeneous group of blistering disorders affecting the mucosae with or without skin involvement, characterized by the presence of autoantibodies to components of the basement membrane zone, including the bullous pemphigoid antigen BP180 and β4 integrin. Current literature has shown that a minority of patients present circulating antibodies to laminin-332 and this population seems to be associated with a relatively high risk of malignancy.

Objective

To present our personal case series of patients with MMP-associated malignancy from a dermatology university hospital.

Methods

Twenty-two patients affected by MMP were seen in the period between 2001 and 2016; in 4 patients (18%) an associated cancer was detected.

Results

These patients were 2 men and 2 women, with a mean age of 69.7 years (range, 48-83). The associated malignancies included a breast cancer, a pancreatic adenocarcinoma, a metastatic laryngeal carcinoma, and a hepatic carcinoma. All patients had negative results for both BP180 and laminin-332 autoantibodies.

Conclusion

We confirm that MMP patients have a relatively high possibility of developing a solid cancer, but the autoantibody detection is not mandatory and is probably correlated with the severity of the disease.

Cutaneous paraneoplastic syndromes

A variety of cutaneous abnormalities can be seen in patients with malignant diseases, some of which are infectious, with others representing direct involvement of the skin by the underlying disorder. Yet another group of lesions can be regarded as associated markers of the malignant process, and, as such, are termed "paraneoplastic." This review considers the latter collection of conditions, grouping them by the generic type of malignancy that is usually linked to the paraneoplasia. Some of the processes show a predominant association with alimentary tract malignancies (acanthosis nigricans, acrodermatitis paraneoplastica, florid cutaneous papillomatosis, necrolytic migratory erythema, palmoplantar keratoderma, pancreatic fat necrosis, and pityriasis rotunda). Others are usually linked to a hematolymphoid malignancy (acquired ichthyosis, exfoliative erythroderma, necrobiotic xanthogranuloma, pemphigus paraneoplastica, plane xanthoma, pyoderma gangrenosum, scleromyxedema, Sweet syndrome, and leukocytoclastic vasculitis). Finally, yet another collection of paraneoplastic skin disorders can associate themselves with anatomically-diverse malignancies (Leser-Trelat syndrome, Trousseau syndrome, dermatomyositis, erythema gyratum repens, hypertrichosis lanuginosa acquisita, papuloerythroderma of Ofuji, tripe palms, and multicentric reticulohistiocytosis). Recognition of these processes by the pathologist can be a valuable step in the characterization of underlying malignant diseases.

Mucous Membrane Pemphigoid, Bullous Pemphigoid, and Anti-programmed Death-1/ Programmed Death-Ligand 1: A Case Report of an Elderly Woman With Mucous Membrane Pemphigoid Developing After Pembrolizumab Therapy for Metastatic Melanoma and Review of the Literature

An 83-year-old patient developed erosions and a blister of the gingival mucous membrane, 6 months after discontinuation of the anti-programmed death-1 (anti PD-1) pembrolizumab therapy administered for 10 months for a metastatic melanoma. A diagnosis of mild mucous membrane pemphigoid (MMP) was made. Complete remission of MMP was rapidly obtained with minimal therapy (doxycycline). MMP remained in complete remission after a 3-month follow-up since discontinuation of the doxycycline therapy and no evidence of relapse of the melanoma was observed after a 14-month follow-up since discontinuation of the pembrolizumab therapy. The widespread use of anti PD-1 and anti-programmed death-ligand-1 (PD-L1) in several malignancies reveals new adverse events. MMP describes a group of chronic, inflammatory, mucous membrane-predominant, subepithelial auto-immune blistering diseases. It is clinically distinct from bullous pemphigoid another autoimmune blistering disease but shares some immunological similarities with it. Twenty-nine cases of bullous pemphigoid associated with anti PD-1/PD-L1 have been reported in the literature and one of MMP. Here, we described the case of a MMP developed after pembrolizumab and discussed the accountability of anti PD-1/PD-L1 in our case and the previous reported bullous pemphigoid and MMP cases using the Begaud system scoring.

Obligate and facultative paraneoplastic dermatoses: an overview

Dermatological paraneoplastic syndromes are a group of cutaneous diseases associated with malignancy, but not directly related to the primary tumor itself or to its metastases. It is of utmost importance for the dermatologist to recognize the major cutaneous paraneoplastic syndromes to diagnose the underlying tumors that trigger them as early as possible. In this overview, skin conditions that are highly correlated with malignancy, whose recognition implies a mandatory investigation of internal cancer, are described.

[Humoral immune diseases: Cutaneous vasculitis and auto-immune bullous dermatoses]

Humoral immunity is the cause of multiple diseases related to antibodies (IgA, IgG, IgM) produced by the patient. Two groups of diseases are identified. The first group is related to circulating antigen-antibody complexes. The antigens are various. They are often unknown. These immune complexes cause a vascular inflammation due to the complement fixation. Consequently, this group is dominated by inflammatory vasculitis. In the second group, the pathology is due to the fixation in situ of antibodies to a target antigen of the skin that is no more recognized by the patient. This group is represented by the auto-immune bullous dermatoses.

Blistering diseases in the mature patient

Autoimmune blistering diseases (AIBD) are a group of chronic diseases affecting the skin and mucous membranes, with different presentation, clinical course, histologic and immunopathologic findings, and different therapeutic approach. Blisters develop as a result of autoantibodies directed against distinct adhesion structures within desmosomes or within the basement membrane zone. The most common AIBD that develops in the elderly is bullous pemphigoid (previously also named "pemphigoid senilis"), but mature patients can also present with other AIBD as mucous membrane pemphigoid, epidermolysis bullosa acquisita, paraneoplastic pemphigus, pemphigus vulgaris, pemphigus foliaceus, linear IgA dermatosis, and dermatitis herpetiformis. There are no differences in treatment approach to mature patients with AIBD, but due to more common comorbidities, systemic therapy should be given with more caution and control, and due to distorted skin integrity in the aged skin, the safety concerns are increased with the long-term use of any topical medication.

Robotic trans-subxiphoid extended thymectomy in a patient with thymoma-associated pemphigus

We herein firstly reported that a patient with thymoma-associated pemphigus (TAP) underwent a robotic-assisted trans-subxiphoid thoracoscopic extended thymectomy and then achieved stable resolution. The patient, a 47-year-old male, was first admitted to our hospital owing to stomatitis and bullae of the trunk after four months' prednisone treatment. On admission, chest computed tomography (CT) revealed an anterior-mediastinal mass and it was initially diagnosed as a thymoma. He was positive for anti-BP (bullous pemphigoid)-180 antibody and anti-desmoglein 3 antibody. Then, a robotic-assisted thymectomy was performed, following which, the anti-BP-180 and anti-desmoglein 3 antibody titres have declined. The patient's mucocutaneous lesions improved, and the steroid dose was gradually decreased from 60 to 40 mg/day. According to previous reports, and the experience of the presented case, we therefore believe that early extended thymectomy is an effective therapeutic intervention for TAP.