Vincent Piguet

Background: Approximately 15% to 25% of adult dermatomyositis cases are associated with underlying cancers. To date, no study has comprehensively synthesized the available evidence on mortality in cancer-associated dermatomyositis. Objective: To explore the clinical characteristics, mortality, and survival outcomes of cancer-related dermatomyositis. Methods: MEDLINE, Embase, and PubMed were searched from inception to August 5, 2025 (PROSPERO CRD420251269785). Observational studies including at least 10 cases and reporting mortality outcomes among adults with cancer-associated dermatomyositis were eligible. Risk of bias and certainty of evidence were assessed using the Grading of Recommendations Assessment, Development, and Evaluation. Random-effects meta-analysis was used to estimate pooled survival outcomes. Results: Twenty-three studies including 974 patients were analyzed with a mean age of 58 years and a female predominance. Head and neck cancers were the most frequently reported malignancies, reflecting population patterns. Muscle weakness, heliotrope rash, and dysphagia were common. Across 16 studies including 605 patients, cancer was diagnosed in the majority of cases (82%) within 2 years of dermatomyositis onset. Patients with cancer-associated dermatomyositis had higher mortality rates than those without malignancy, with worse 1- and 5-year survival (low certainty of evidence). Only 2 studies assessed mean survival time, with a pooled estimate of 4.57 years from dermatomyositis diagnosis (95% CI, 2.08-7.05; I ² = 0%). Conclusions: This review synthesizes the available evidence on cancer-associated dermatomyositis and reinforces its association with poor prognosis. Larger studies with standardized reporting of serological profiles and mortality outcomes are needed to better characterize survival and prognostic factors.

Background/Objectives: Incretin-based therapies, including glucagon like peptide-1 receptor agonists (GLP-1 RAs) and glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 RAs, are increasingly prescribed for obesity, leading to greater recognition of associated dermatological adverse events (AEs). We aimed to characterize the spectrum, frequency, and clinical characteristics of cutaneous AEs reported with semaglutide, liraglutide and tirzepatide, focusing on these agents because of their established use in both weight management and diabetes mellitus. Methods: A systematic literature search was conducted in MEDLINE (via PubMed), Embase, and Web of Science. Search terms combined skin-related manifestations (e.g., skin, dermatologic, injection-site reactions, pruritus, rash, hypersensitivity, dysesthesia, vasculitis) with GLP-1 RA and GIP/GLP-1 RAs (semaglutide, tirzepatide, liraglutide). Clinical trials, observational studies, pharmacovigilance studies, and case reports reporting skin-related AEs associated with semaglutide, liraglutide and tirzepatide were included. Results: One hundred and one studies were included (32 randomized controlled trials, 6 retrospective cohort/cross-sectional studies, 20 pharmacovigilance studies, and 43 case series/reports). Cutaneous AEs ranged from generally common but mild reactions to rare but potentially severe immune-mediated disorders. Injection-site reactions, including erythema, pruritus, and hemorrhage, were reported most frequently with tirzepatide (2–7%), then liraglutide, and less commonly with semaglutide, with evidence of dose dependence. Dysesthesia was most strongly associated with semaglutide, occurring in approximately 5% of patients at standard doses and up to 20% with high-dose formulations indicated for weight management, with events frequently occurring during dose escalation. Uncommon reactions reported in association with GLP-1 or GIP/GLP-1 RA use included angioedema, hypersensitivity reactions, autoimmune blistering diseases, drug eruptions, vasculitis, and severe cutaneous reactions. Conclusions: Although most cutaneous AEs associated with GLP-1 and GIP/GLP-1 RAs are mild and manageable, clinically relevant drug-specific differences exist. The recognition of common and uncommon skin manifestations may facilitate earlier diagnosis, support treatment adherence, and reduce the adverse outcomes.

Facial and neck erythema (FNE) is a bothersome adverse effect associated with dupilumab treatment for atopic dermatitis (AD). It is unclear how to optimally manage this condition. To systematically review and summarize cases of dupilumab-associated FNE and to identify reported etiologies and management strategies. A search was conducted on EMBASE and MEDLINE databases to update a systematic review published in 2021. We identified 867 cases of dupilumab-related FNE, of which 54.9% were de novo 39.2% were worsening of preexisting FNE. Reported etiologies of dupilumab-induced FNE included allergic contact dermatitis (21.2%, 184/867), Malassezia furfur hypersensitivity (13.5%, 117/867), and residual AD (2.8%, 24/867). Reported management strategies included topical monotherapy (28.4%, 253/892; most commonly, topical corticosteroids (TCS) with topical calcineurin inhibitors [TCIs]), oral monotherapy (21.3%, 190/892; most commonly oral antifungals and upadacitinib), and combination of topical/oral treatments (8.1%, 72/892; most commonly TCS/TCI/oral antifungal combination). Complete resolution (CR) was seen with topical antifungals (69.6%, 16/23), oral antifungals (66.1%, 82/124), and upadacitinib (100%, 35/35). Of patients who continued dupilumab with no subsequent intervention, 27.7% (13/47) had CR. This study is limited by a lack of standardized reporting, a lack of head-to-head or placebo comparison, and potential publication bias. Dupilumab-associated FNE has the potential to resolve with topical and oral medications. Prospective, controlled studies are indicated to elucidate optimal management strategies.

The physiological effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) and dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1RAs extend beyond glucose metabolism and body weight regulation. Accumulating clinical evidence has highlighted an association between these incretin-based therapies and hair loss; however, the underlying molecular mechanisms are not fully understood. White adipose tissue (WAT) is increasingly recognized as a critical regulator of hair follicle homeostasis that may undergo substantial drug-associated functional alterations. Thus, GLP-1RAs and GIP/GLP-1RAs may indirectly modulate hair follicle biology and promote hair loss through changes in adipocyte function. This review assesses the effects of GLP-1RAs and GIP/GLP-1RAs on WAT, synthesizing findings from cellular systems, animal models, and human clinical research. Collectively, these therapies may influence adipocyte differentiation, adipokine secretion, and pro-inflammatory cytokine signaling in a context-dependent manner; however, most data are derived from subcutaneous WAT and have yet to be established in the distinct dermal WAT compartment that surrounds hair follicles. Accordingly, we propose a hypothetical, non-exclusive model in which drug-associated adipocyte reprogramming may alter the hair follicle microenvironment and disrupt normal follicular cycling, potentially contributing to increased hair shedding. Validation of this potential pathway is required and may inform the development of targeted strategies to prevent or treat this adverse event.

Recent evidence indicates that both the bacterial composition of the skin and gut microbiota may contribute to the pathogenesis and progression of hidradenitis suppurativa (HS). Several studies have identified alterations in the skin bacterial microbiota, including an increased abundance of anaerobic taxa such as Prevotella spp. and Porphyromonas spp., alongside a reduction in commensal species like Cutibacterium spp., changes that may promote chronic inflammation and biofilm formation. Comparative analyses of lesional versus non-lesional skin have also revealed enrichment of bacterial pathways related to cell growth, DNA replication, and mismatch repair, suggesting enhanced microbial proliferation within HS lesions. Emerging evidence further suggests the presence of bacterial gut dysbiosis in HS, with some studies reporting reduced microbial diversity and lower abundance of protective genera Ruminococcaceae, and Lachnospiraceae families. Efforts to modulate the skin and gut microbiota in HS are underway, exploring approaches such as dietary modification, antibiotic usage, and probiotic supplementation. Moreover, comorbid conditions frequently associated with HS appear to influence disease severity and may mediate the relationship between microbial imbalance and systemic inflammation. Despite these insights, current research remains fragmented, characterized by small sample sizes, heterogeneous study designs, and a scarcity of robust interventional data.

Scalp dysesthesia is a poorly understood condition characterized by chronic scalp pruritus and pain in the absence of underlying cutaneous disease. Delayed diagnosis, limited clinician awareness, and inconsistent therapeutic responses continue to complicate management. This scoping review aimed to synthesize current evidence regarding the clinical presentation, diagnosis, and treatment of scalp dysesthesia. A comprehensive review of the literature was conducted, with data extracted from 20 studies describing 59 patients, the majority of whom were middle‐aged and older women. Common comorbidities included spinal musculoskeletal pathology and psychiatric conditions. Collectively, the clinical findings and evolving understanding of neuronal signaling support a potential neuropathic component to scalp dysesthesia, likely influenced by both physiologic factors, such as inflammation, hormonal changes, and aging, and psychological contributors including anxiety and depression. Diagnosis requires extensive evaluation to exclude differential diagnoses and typically involves patient history, physical examination, imaging, and laboratory investigations. Frequently reported management strategies included corticosteroids, antibiotics/antifungals, antidepressants, and gabapentinoids, although treatment efficacy was inconsistent between patients. Preliminary observations suggest that emerging therapies, such as exercise‐based interventions, onabotulinumtoxin A, pain receptor antagonists, surgery, and biologics, may have potential benefits; however, evidence remains limited by small sample sizes. Further work is needed to standardize diagnostic approaches, improve clinician awareness, clarify pathogenesis, and establish evidence‐based, mechanism‐driven treatment strategies for scalp dysesthesia. image