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.

Outcome Measurement Instruments Used to Evaluate Dermatologic Adverse Events in Cancer Trials: A Systematic Review.

Importance: Assessment of type, severity, and impact of dermatologic adverse events (DAEs) necessitates well-developed and validated clinician-reported outcome measures (ClinROMs) and patient-reported outcome measures (PROMs) that evaluate concepts specific to mucocutaneous toxic effects and that allow appropriate interpretation and comparison of DAEs across trials. Objective: To evaluate heterogeneity and quality of ClinROMs and PROMs used to assess DAEs from systemic cancer therapy. Evidence Review: Two systematic reviews were conducted by searching PubMed and Embase databases from inception through March 7, 2023, and April 12, 2023. The first search included randomized clinical trials and observational studies reporting systemic cancer treatment-induced DAEs assessed by a ClinROM or PROM. The second included studies evaluating measurement properties of frequently used ClinROM and PROM instruments. The Consensus-Based Standards for the Selection of Health Measurement Instruments risk of bias tool was used to evaluate methodologic quality of validation assessments. Findings: A total of 395 studies were included. The Common Terminology Criteria for Adverse Events (CTCAE) was utilized in 331 studies meeting inclusion criteria (83.8%). At least 1 skin-related PROM was infrequently utilized in systemic chemotherapy clinical trials (79 studies [20.0%]). Most frequently utilized PROMs were the Dermatology Life Quality Index (DLQI; 34 studies [8.6%]) and Skindex-16 (20 studies [5.1%]). Among studies capturing DAEs, 115 (29.1%) reported a nondescript term (ie, rash) as the only DAE. Eight studies described 44 property assessments of the CTCAE, DLQI, and Skindex. There were no studies evaluating content validity, intrarater reliability, or measurement error for the CTCAE, DLQI, or Skindex. There were no studies evaluating structural validity, internal consistency, and responsiveness of DLQI or Skindex. Interrater reliability and responsiveness were each assessed for 1 DAE-related component of the CTCAE. Construct validity for CTCAE, DLQI, and Skindex was evaluated in 29 (65.9%), 3 (6.8%), and 9 (20.5%) assessments, respectively. Conclusions and Relevance: In this systematic review, there was a narrow spectrum of ClinROMs and PROMs with limited validity for the measurement of DAEs in the context of systemic chemotherapy interventions in clinical trials. Report of trial DAEs often had low morphologic specificity and meaning. Based on existing gaps in measurement and report of DAEs, a frequent and impactful adverse event to chemotherapy, the framework for evaluating cutaneous toxic effects in oncology trials may need collaborative reevaluation.

Oral sirolimus for the treatment of juvenile xanthogranuloma: Report of two pediatric cases.

Juvenile xanthogranuloma (JXG) with extensive cutaneous or visceral organ involvement is often associated with high morbidity and treatment commonly involves surgical excision, radiotherapy, systemic steroids, or chemotherapy. Sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, is an oral antitumor and immunosuppressive therapy used to treat various neoplastic disorders, including histiocytic disorders. We report two pediatric cases of JXG successfully treated with oral sirolimus monotherapy, and postulate that sirolimus may induce rapid disease resolution and long-term remission for patients with both skin-limited and multisystemic JXG. Our findings warrant further investigation of the relationship between the mTOR pathway and JXG.

Eligibility Criteria for Active Ulcerative Pyoderma Gangrenosum in Clinical Trials: A Delphi Consensus on Behalf of the UPGRADE (Understanding Pyoderma Gangrenosum: Review and Assessment of Disease Effects) Group.

At present, there are no standardized guidelines for determining patient eligibility for pyoderma gangrenosum (PG) clinical trials. Thus, we aim to determine which clinical features, histopathological features, or laboratory features should be included in active ulcerative PG clinical trial eligibility criteria for treatment-naïve patients and patients already treated with immunomodulating medications (treatment-exposed patients). This study employed 4 rounds of the Delphi technique. Electronic surveys were administered to 21 international board-certified dermatologists and plastic surgeon PG experts (June 2022-December 2022). Our results demonstrated that for a patient to be eligible for a PG trial, they must meet the following criteria: (i) presence of ulcer(s) with erythematous/violaceous undermining wound borders, (ii) presence of a painful or tender ulcer, (iii) history/presence of rapidly progressing disease, (iv) exclusion of infection and other causes of cutaneous ulceration, (v) biopsy for H&E staining, and (vi) a presence/history of pathergy. These criteria vary in importance for treatment-naïve versus treatment-exposed patients. Given the international cohort, we were unable to facilitate live discussions between rounds. This Delphi consensus study provides a set of specific, standardized eligibility criteria for PG clinical trials, thus addressing one of the main issues hampering progress toward Food and Drug Administration approval of medications for PG.

Development of a Skin-Directed Scoring System for Stevens-Johnson Syndrome and Epidermal Necrolysis: A Delphi Consensus Exercise.

Importance: Scoring systems for Stevens-Johnson syndrome and epidermal necrolysis (EN) only estimate patient prognosis and are weighted toward comorbidities and systemic features; morphologic terminology for EN lesions is inconsistent. Objectives: To establish consensus among expert dermatologists on EN terminology, morphologic progression, and most-affected sites, and to build a framework for developing a skin-directed scoring system for EN. Evidence Review: A Delphi consensus using the RAND/UCLA appropriateness criteria was initiated with a core group from the Society of Dermatology Hospitalists to establish agreement on the optimal design for an EN cutaneous scoring instrument, terminology, morphologic traits, and sites of involvement. Findings: In round 1, the 54 participating dermatology hospitalists reached consensus on all 49 statements (30 appropriate, 3 inappropriate, 16 uncertain). In round 2, they agreed on another 15 statements (8 appropriate, 7 uncertain). There was consistent agreement on the need for a skin-specific instrument; on the most-often affected skin sites (head and neck, chest, upper back, ocular mucosa, oral mucosa); and that blanching erythema, dusky erythema, targetoid erythema, vesicles/bullae, desquamation, and erosions comprise the morphologic traits of EN and can be consistently differentiated. Conclusions and Relevance: This consensus exercise confirmed the need for an EN skin-directed scoring system, nomenclature, and differentiation of specific morphologic traits, and identified the sites most affected. It also established a baseline consensus for a standardized EN instrument with consistent terminology.

Diagnostic work-up and treatment in patients with pyoderma gangrenosum: retrospective analysis of US insurance claims-based data.

Pyoderma gangrenosum (PG) is a rare, and often challenging to diagnose, inflammatory disorder with relatively high rates of morbidity and mortality. Central to the diagnosis of PG is histologic evaluation and exclusion of other entities. Large-scale studies investigating the proportion of patients receiving a thorough diagnostic work-up, as well as prevalence studies regarding comorbidities and systemic treatment in PG using claims-based data, are sparse. Our objective was to identify patients diagnosed with PG and describe the diagnostic work-up and prevalence of common comorbidities and therapies in this population using claims-based data in a retrospective cohort study. In order to better understand practices of diagnostic work-up, we captured rates of skin biopsy, tissue culture, and/or surgical debridement prior to initial diagnosis. We also identified the prevalence of PG-associated comorbidities and initial immunosuppressive therapy given for PG. Of the 565 patients diagnosed with PG, 9.4% underwent skin biopsy, 8% tissue culture, and 1.4% both skin biopsy AND tissue culture prior to diagnosis. Inflammatory bowel disease was the most prevalent comorbidity (16.3%). The most common treatment administered was systemic corticosteroids (17%). Although practice guidelines explicitly delineate histology and exclusion of infection as important diagnostic criteria, only a minority of patients in this study underwent skin biopsy and/or tissue culture prior to receiving a diagnosis of PG, suggesting that patients may receive a diagnosis of PG without having tissue evaluation. Such discordance between practice guidelines and "real-world" practice inevitably increases the risk for misdiagnosis of PG and misdirected treatment with immunosuppressants for presumptive PG in cases of PG mimickers. Moreover, comorbidities associated with PG may occur, or be identified in, a lower proportion of patients as compared with what is reported in the existing literature. Study limitations include a population restricted to < 65 years with commercial insurance and the reliance upon ICD diagnostic coding to capture the population.

Clinical Characteristics, Disease Course, and Outcomes of Patients With Acute Generalized Exanthematous Pustulosis in the US.

Importance: Acute generalized exanthematous pustulosis (AGEP) is a rare, severe cutaneous adverse reaction associated with systemic complications. Currently available data are largely limited to small retrospective case series. Objective: To describe the clinical characteristics, disease course, and outcomes of a heterogeneous group of patients with AGEP across the US. Design, Setting, and Participants: A retrospective review of a case series of patients was conducted from January 1, 2000, through July 31, 2020. All 340 included cases throughout 10 academic health systems in the US were scored retrospectively using the EuroSCAR scoring system, and patients with a score corresponding to probable or definite AGEP and aged 18 years or older were included. Main Outcomes and Measures: Patient demographic characteristics, clinical course, suspected causative agent, treatment, and short- and long-term outcomes. Results: Most of the 340 included patients were women (214 [62.9%]), White (206 [60.6%]), and non-Hispanic (239 [70.3%]); mean (SD) age was 57.8 (17.4) years. A total of 154 of 310 patients (49.7%) had a temperature greater than or equal to 38.0 °C that lasted for a median of 2 (IQR, 1-4) days. Of 309 patients, 263 (85.1%) developed absolute neutrophilia and 161 patients (52.1%) developed either absolute or relative eosinophilia. Suspected causes of AGEP were medications (291 [85.6%]), intravenous contrast agents (7 [2.1%]), infection (3 [0.9%]), or unknown (39 [11.5%]). In 151 cases in which a single medication was identified, 63 (41.7%) were ß-lactam antimicrobials, 51 (33.8%) were non-ß-lactam antimicrobials, 9 (6.0%) were anticonvulsants, and 5 (3.3%) were calcium channel blockers. The median time from medication initiation to AGEP start date was 3 (IQR, 1-9) days. Twenty-five of 298 patients (8.4%) had an acute elevation of aspartate aminotransferase and alanine aminotransferase levels, with a peak at 6 (IQR, 3-9) days. Twenty-five of 319 patients (7.8%) experienced acute kidney insufficiency, with the median time to peak creatinine level being 4 (IQR, 2-5) days after the AGEP start date. Treatments included topical corticosteroids (277 [81.5%], either alone or in combination), systemic corticosteroids (109 [32.1%]), cyclosporine (10 [2.9%]), or supportive care only (36 [10.6%]). All-cause mortality within 30 days was 3.5% (n = 12), none of which was suspected to be due to AGEP. Conclusions and Relevance: This retrospective case series evaluation of 340 patients, the largest known study cohort to date, suggests that AGEP onset is acute, is usually triggered by recent exposure to an antimicrobial, may be associated with liver or kidney complications in a minority of patients, and that discontinuation of the triggering treatment may lead to improvement or resolution.

Lack of distinct molecular profile of Primary Dermal Melanoma.

Primary dermal melanoma (PDM) is a rare variant of melanoma which simulates metastatic melanoma to the skin. Diagnosis of PDM cannot be established on histologic grounds alone but requires absence of evidence of melanoma elsewhere by clinical history and/or imaging studies. Despite this entity being clinically well documented, limited data on molecular characterization are available. We performed comprehensive mutation and copy number variation analysis in a series of PDMs in search for distinctive molecular features.Studies were approved by respective institutional review boards. Six cases fulfilling strict histologic criteria of PDM were identified in patients with absent history of melanoma elsewhere, negative sentinel lymph node biopsies and imaging studies. DNA was extracted from formalin-fixed, paraffin-embedded (FFPE) tissue, and five cases passed quality control measures and were subjected to targeted exon sequencing using the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets 410 panel. Two of five PDM carried NRAS hotspot mutations characteristic of cutaneous melanoma (CM) genomic subtypes. One case showed a probable low-activating NRAS mutation in combination with additional aberrations in other mitogen-activated protein kinase (MAPK) pathway effectors. Hotspot mutations were also identified in the TERT promoter region, and one tumor showed a mutation in the SWI/SNF remodeling complex. No oncogenic mutations were identified in one case. Furthermore, none of the tumors analyzed showed activating mutations in Gα subunits, including GNAQ and GNA11. Copy number alterations included deletions of Chr 9p, characteristic of CM.Despite PDM showing mutational heterogeneity, our findings suggest predominance of MAPK pathway aberrations in agreement with the mutational profile of CMs in general. Given the absence of genetic overlap with other distinct primary dermal melanocytic proliferations, mutational profiling will unlikely aid in the difficult differential diagnosis of PDM versus melanoma metastasis. Thorough metastatic workup remains crucial in establishing this rare diagnosis.

Comparison between organismal staining on histology and tissue culture in the diagnosis of cutaneous infection: A retrospective study.

BACKGROUND: In instances of suspected cutaneous infection, the standard of care includes obtaining skin biopsy specimens for histology and tissue culture. Few studies have compared the clinical utility of each test. OBJECTIVE: To assess the concordance of results between tissue culture and histology, as well as the clinicopathologic features that may influence the diagnostic yield of each test. METHODS: A retrospective review of all patients who underwent skin biopsy for histology and tissue culture at New York University from 2013 through 2018. RESULTS: Of 179 patients, 10% had positive concordance, 21% had positive tissue culture only, and 7% had positive histology only. We calculated a kappa correlation coefficient of 0.25 between histology and tissue culture (reference, 0.21-0.39 indicates minimal agreement). Histology exhibited higher sensitivity in detecting fungi, whereas tissue culture was more sensitive in identifying Gram-negative bacteria. Antimicrobial use before biopsy led to significantly fewer positive cultures (37.5% vs 71%; P = .023) in patients ultimately diagnosed with infection. LIMITATIONS: This study was conducted at a single institution, thereby restricting its broad applicability. The lack of a validated criterion standard to diagnose infection also limits interpretation of the results. CONCLUSION: Tissue culture and histopathology often yield discordant results. Dermatologists should recognize specific limitations, yet high clinical utility in special circumstances, of tests when approaching cases of suspected infection.

Resident Rounds Part III: Case Report: Fatal Cryptococcal Panniculitis in a Lung Transplant Recipient.

Cryptococcal panniculitis is a rare entity previously reported in only 13 solid organ transplant (SOT) recipients. Cutaneous cryptococcosis in SOT recipients warrants extensive systemic workup and treatment as if central nervous system (CNS) disease is present. It should be included in the differential diagnosis of panniculitis in the immunocompromised host, as early diagnosis and treatment are critical. We report a fatal case of cryptococcal panniculitis in a 44-year-old lung transplant recipient.