RESUMO
Habitat anthropization is a major driver of global biodiversity decline. Although most species are negatively affected, some benefit from anthropogenic habitat modifications by showing intriguing life-history responses. For instance, increased recruitment through higher allocation to reproduction or improved performance during early-life stages could compensate for reduced adult survival, corresponding to "compensatory recruitment". To date, evidence of compensatory recruitment in response to habitat modification is restricted to plants, limiting understanding of its importance as a response to global change. We used the yellow-bellied toad (Bombina variegata), an amphibian occupying a broad range of natural and anthropogenic habitats, as a model species to test for and to quantify compensatory recruitment. Using an exceptional capture-recapture dataset composed of 21,714 individuals from 67 populations across Europe, we showed that adult survival was lower, lifespan was shorter, and actuarial senescence was higher in anthropogenic habitats, especially those affected by intense human activities. Increased recruitment in anthropogenic habitats fully offset reductions in adult survival, with the consequence that population growth rate in both habitat types was similar. Our findings indicate that compensatory recruitment allows toad populations to remain viable in human-dominated habitats and might facilitate the persistence of other animal populations in such environments.
Assuntos
Efeitos Antropogênicos , Anuros , Biodiversidade , Animais , Europa (Continente) , Dinâmica PopulacionalRESUMO
The lupus band test (LBT) is frequently performed for patients with lupus erythematosus (LE) but its capacity to discriminate cutaneous (C)LE from systemic (S)LE is debated, as well as its association with serum antinuclear antibodies (ANA) and complement reduction. Among 158 patients, 56 received retrospectively a diagnosis of CLE, 37 have SLE and 65 other skin disorders. Considering 29 clinical, histopathologic, LBT, and serological parameters: 5 parameters were effective in distinguishing LE from other skin disorders (e.g. skin photosensitivity, LBT positivity, basal vacuolar changes, thickening of the basement membrane, and anti-SSA-60 kDa); and 8 parameters were able to separate SLE from CLE (e.g. arthritis, lupus nephritis, hematological manifestations, Raynaud/sicca manifestations, anti-chromatin, anti-dsDNA, and low levels of C3/4). A positive LBT was further determined to be associated with systemic manifestations when associated with anti-chromatin response and complement reduction in the profile of patients evolving to a systemic form of lupus.
Assuntos
Anticorpos Antinucleares/sangue , Cromatina/imunologia , Proteínas do Sistema Complemento/análise , Lúpus Eritematoso Cutâneo/diagnóstico , Lúpus Eritematoso Sistêmico/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Lúpus Eritematoso Cutâneo/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Annular lipoatrophy of the ankle is a rare and unique acquired lipoatrophic panniculitis that mainly affects children. There is no consensus on treatment, and the long-term course is not well known. We present four new pediatric cases that contribute to the understanding of this rare disease.
Assuntos
Lipodistrofia , Paniculite , Tornozelo , Atrofia/patologia , Criança , Humanos , Lipodistrofia/diagnóstico , Paniculite/patologia , Gordura Subcutânea/patologiaRESUMO
AIMS: We applied the 2017 World Health Organization (WHO) classification criteria to categorise a series of 64 primary cutaneous large B-cell lymphomas (PCLBCLs), containing a majority (≥80%) of large cells and a proliferative rate of ≥40%, raising the problem of the differential diagnosis between PCLBCL, leg type (PCLBCL-LT) and primary cutaneous follicle centre lymphoma, large cell (PCFCL-LC). The aims were to determine the reproducibility and prognostic relevance of the 2017 WHO criteria. METHODS AND RESULTS: Morphology and phenotype identified 32 PCLBCLs-LT and 25 PCFCLs-LC; seven cases (11%) remained unclassified. Morphology was less reproducible than immunophenotype. Pertinent markers for the differential diagnosis were MUM1, FOXP1, CD10, and IgM. bcl-2 and bcl-6 were expressed by both PCFCLs-LC and PCLBCLs-LT at substantial levels. Neither Ki67 expression nor p63 expression was of diagnostic value. MYD88 was found to be mutated only in PCLBCLs-LT (n = 22, 69%). According to Hans/Hans modified algorithms, 23 of 25 PCFCLs-LC had germinal centre (GC) status, and the 32 PCLBCLs-LT had non-GC status. Overall survival was poorer for PCLBCLs-LT than PCFCLs-LC (P = 0.0002). Non-GC cases had poorer overall survival than GC cases (P = 0.0007). In PCLBCLs-LT, MYC expression was associated with cutaneous relapses (P = 0.014). When GC/non-GC status was applied to unclassified cases, only a single case remained discordant. CONCLUSIONS: Our results support the 2017 WHO classification criteria for PCLBCL diagnosis. The Hans modified algorithm using CD10 and MUM1 distinguished PCFCLs-LC from PCLBCLs-LT with optimal diagnostic value without requiring bcl-6 immunolabelling (poorly reproducible). Rare unclassified cases may constitute a provisionally heterogeneous subgroup for which GC/non-GC status (relevant for prognosis) may guide therapeutic decisions.
Assuntos
Biomarcadores Tumorais/análise , Linfoma de Células B/classificação , Linfoma Folicular/classificação , Neoplasias Cutâneas/classificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Centro Germinativo/patologia , Humanos , Imunofenotipagem , Linfoma de Células B/diagnóstico , Linfoma de Células B/patologia , Linfoma Folicular/diagnóstico , Linfoma Folicular/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Organização Mundial da SaúdeRESUMO
A 49-year-old man underwent ABO-incompatible kidney transplantation with a living donor. At day 33 post-transplantation, he presented with undiagnosed epilepsy with generalized tonic-clonic seizures. At day 44 post-transplantation, he developed left-sided pneumonia attributed to Aspergillus fumigatus and treatment with liposomal amphotericin B was initiated. At day 51 post-transplantation, necrotic skin lesions appeared. DNA sequencing in a fresh cutaneous biopsy finally identified Cunninghamella Spp., a member of the order Mucorales. Unfortunately, the necrotic lesions spread, and the patient died at day 60 post-transplantation. This case report highlights the infectious risk related to ABO-incompatible kidney transplantation and suggests a requirement for rapid identification of every skin lesion, even in the early phases of immunosuppression.
Assuntos
Incompatibilidade de Grupos Sanguíneos/complicações , Cunninghamella/isolamento & purificação , Dermatomicoses/imunologia , Transplante de Rim/efeitos adversos , Mucormicose/imunologia , Sistema ABO de Grupos Sanguíneos/imunologia , Aloenxertos/imunologia , Incompatibilidade de Grupos Sanguíneos/imunologia , Cunninghamella/imunologia , Dermatomicoses/microbiologia , Dermatomicoses/patologia , Evolução Fatal , Humanos , Rim/imunologia , Transplante de Rim/métodos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Mucormicose/microbiologia , Mucormicose/patologia , Necrose/imunologia , Necrose/microbiologia , Necrose/patologia , Pele/microbiologia , Pele/patologiaRESUMO
BACKGROUND: Calciphylaxis (CPX) is a rare and life-threatening disease characterized by vascular calcification and development of painful and necrotizing skin lesions with a challenging management. Mechanisms of CPX are complex and include an imbalance between vascular calcification promoters and inhibitors, and frequently vitamin K deficiency. OBJECTIVES: To describe the various presentations and identify predictive factors of death in patients with CPX. METHODS: In this multicenter retrospective study, we included 71 CPX patients followed in South-West France (n = 26) and in French Polynesia (n = 45), and who all received sodium thiosulfate (25 g thrice weekly for a median of 61 days). RESULTS: Characteristics at presentation significantly differed between metropolitan and Polynesian French patients. Polynesians were less frequently on regular dialysis at the onset of CPX, had a higher incidence of diabetes mellitus and obesity, more disturbances of calcium-phosphorus metabolism, and received vitamin K antagonists less frequently than patients from South-West France. Despite intensive management, the 1-year mortality rate was 66% and median time to death was 200 days (IQR, 40; 514). The number of body areas involved (i.e., three: OR 2.70 [1.09; 6.65], p = 0.031; four: OR 8.79 [1.54; 50.29], p = 0.015) was the only predictive factor for death, whereas application of topical cerium nitrate-silver sulfadiazine was protective (OR 0.44 [0.20; 0.99], p = 0.046). Surgical debridement, hyperbaric oxygenation therapy, and geographical origin were not associated with overall outcomes. CONCLUSIONS: Cerium nitrate may lead to vascular decalcification and chelation of reactive oxygen species, and prevent infection. Cerium nitrate-silver sulfadiazine was associated with better outcomes and should be tested in a prospective comparative trial in CPX patients.
Assuntos
Anti-Infecciosos Locais/uso terapêutico , Calciofilaxia/terapia , Cério/uso terapêutico , Sulfadiazina de Prata/uso terapêutico , Dermatopatias Vasculares/tratamento farmacológico , Administração Cutânea , Idoso , Anti-Infecciosos Locais/administração & dosagem , Calciofilaxia/etiologia , Cério/administração & dosagem , Quelantes , Combinação de Medicamentos , Feminino , França , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Polinésia , Diálise Renal , Estudos Retrospectivos , Fatores de Risco , Sulfadiazina de Prata/administração & dosagem , Dermatopatias Vasculares/etiologia , Taxa de Sobrevida , Tiossulfatos/uso terapêutico , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: The Wnt/ß-catenin pathway is the most frequently deregulated pathway in hepatocellular carcinoma (HCC). Inactivating mutations of the gene encoding AXIN1, a known negative regulator of the Wnt/ß-catenin signaling pathway, are observed in about 10% of HCCs. Whole-genome studies usually place HCC with AXIN1 mutations and CTNNB1 mutations in the group of tumors with Wnt/ß-catenin activated program. However, it has been shown that HCCs with activating CTNNB1 mutations form a group of HCCs, with a different histology, prognosis and genomic signature to those with inactivating biallelic AXIN1 mutations. We aimed to elucidate the relationship between CTNNB1 mutations, AXIN1 mutations and the activation level of the Wnt/ß-catenin program. METHODS: We evaluated two independent human HCC datasets for the expression of a 23-ß-catenin target genes program. We modeled Axin1 loss of function tumorigenesis in two engineered mouse models and performed gene expression profiling. RESULTS: Based on gene expression, we defined three levels of ß-catenin program activation: strong, weak or no activation. While more than 80% CTNNB1-mutated tumors were found in the strong or in the weak activation program, most of the AXIN1-mutated tumors (>70%) were found in the subgroup with no activation. We validated this result by demonstrating that mice with a hepatocyte specific AXIN1 deletion developed HCC in the absence of ß-catenin induction. We defined a 329-gene signature common in human and mouse AXIN1 mutated HCC that is highly enriched in Notch and YAP oncogenic signatures. CONCLUSIONS: AXIN1-mutated HCCs occur independently of the Wnt/ß-catenin pathway and involve Notch and YAP pathways. These pathways constitute potentially interesting targets for the treatment of HCC caused by AXIN1 mutations. LAY SUMMARY: Liver cancer has a poor prognosis. Defining the molecular pathways involved is important for developing new therapeutic approaches. The Wnt/ß-catenin pathway is the most frequently deregulated pathway in hepatocellular carcinoma (HCC). Mutations of AXIN1, a member of this pathway, represent about 10% of HCC mutations. Using both human HCC collections and engineered mouse models of liver cancers with AXIN1 mutation or deletion, we defined a common signature of liver tumors mutated for AXIN1 and demonstrate that these tumors occur independently of the activation of the Wnt/ß-catenin pathway.
Assuntos
Proteína Axina/deficiência , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , Animais , Proteína Axina/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinoma Hepatocelular/genética , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas Experimentais/etiologia , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Camundongos , Camundongos Knockout , Mutação , Prognóstico , Receptores Notch/genética , Receptores Notch/metabolismo , Via de Sinalização Wnt/genética , beta Catenina/metabolismoRESUMO
AIMS: The diagnosis of malignant peripheral nerve sheath tumour (MPNST) may be challenging, especially in the sporadic setting. Owing to the lack of specific histological criteria, immunohistochemical and molecular diagnostic markers, several differential diagnoses must be considered, especially melanoma. Indeed, although S100 protein usually stains melanoma, other melanocytic markers are often negative, especially in spindle cell/desmoplastic types. This pattern of immunoreactivity resembles that of some nerve-derived tumours such as MPNST. Owing to their different clinical behaviours and therapeutic implications, accurate identification of these two different tumours is crucial. METHODS AND RESULTS: S100, SOX10, KBA62, MITF, HMB45, Melan-A, tyrosinase PNL2 and BRAF-V600E immunostaining was performed in a pathologically and genetically well-characterised cohort of primary MPNST (n = 124), including 66 (53%) NF1-associated tumours. Sox10 and KBA62 expression were found, respectively, in 102 (84%) and in 101 (83%) MPNST, whereas S100 was expressed in 64 cases (52%). We observed an increased loss of S100 with increasing histological grade (P = 0.0052). We found Melan-A expression in 14% (n = 17) of all MPNST, occurring in 82% (n = 14) of cases in an NF1 context. Six per cent (n = 8) of MPNST showed tyrosinase positivity, including seven (87%) NF1-associated. MITF expression was found in 10 (8%) MPNST. None expressed PNL2, HMB45 or BRAF-V600E. CONCLUSION: MPNST (in NF1 and a sporadic setting) can quite often be positive for Melan-A, tyrosinase and MITF. Pathologists should be cognisant of these exceptions to prevent confusion with melanoma.
Assuntos
Biomarcadores Tumorais/metabolismo , Melanócitos/metabolismo , Melanoma/diagnóstico , Neurofibrossarcoma/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Antígeno MART-1/metabolismo , Masculino , Melanócitos/patologia , Melanoma/metabolismo , Melanoma/patologia , Monofenol Mono-Oxigenase/metabolismo , Neurofibrossarcoma/metabolismo , Neurofibrossarcoma/patologia , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas S100/metabolismo , Fatores de Transcrição SOXE/metabolismoRESUMO
In this observation, we report an unusual presentation of a pilomatricoma in an 8-year-old girl who was initially referred to the department of vascular medicine for diagnosis and care of a suspected mixed lymphatic venous malformation. The lesion on her left shoulder presented as a giant bluish-purple red solitary mass, painful and rapidly growing, measuring 7 cm in anteroposterior diameter. This mass did not present the typical characteristics of a lymphatic venous malformation but exhibited warning signs of malignancy on clinical examination and imaging. The diagnosis of pilomatricoma was reached by fine-needle aspiration biopsy of the mass, showing mummified "ghost" squamous cells and a granulomatous inflammatory reaction stroma with scattered multinucleated giant cells and no sign of malignancy. Complete surgical excision associated with plastic surgery was curative. Diagnostic and management approach to skin lesion in childhood is subject of great concern for health care professionals, including dermatologists and vascular medicine specialists who may be confronted with this atypical presentation of one of the most common causes of superficial neck masses in children.
Assuntos
Doenças do Cabelo/patologia , Neovascularização Patológica , Pilomatrixoma/irrigação sanguínea , Pilomatrixoma/patologia , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/patologia , Biópsia por Agulha Fina , Criança , Progressão da Doença , Feminino , Doenças do Cabelo/cirurgia , Humanos , Pilomatrixoma/cirurgia , Neoplasias Cutâneas/cirurgia , Fatores de Tempo , Carga Tumoral , Ultrassonografia Doppler em CoresRESUMO
Oral lichen planus (OLP) is a chronic inflammatory disease considered as a CD8+ T lymphocyte-mediated autoimmune reaction, which may be triggered by undetermined virus. Recent reports have described the detection of Merkel cell polyomavirus (MCPyV) DNA in oral samples from healthy patients and in patients with different forms of oral cancers. We therefore investigated in a prospective way whether MCPyV was detectable in oral lesions of patients with active OLP. Our preliminary results do not support the hypothesis that OLP may be triggered by MCPyV infection. Further studies are needed to evaluate the involvement of other human polyomaviruses in OLP pathogenesis.
Assuntos
Líquen Plano Bucal/virologia , Poliomavírus das Células de Merkel/genética , Poliomavírus das Células de Merkel/isolamento & purificação , Boca/virologia , Infecções por Polyomavirus/virologia , Adulto , Idoso , DNA Viral/isolamento & purificação , Feminino , Humanos , Líquen Plano Bucal/complicações , Masculino , Pessoa de Meia-Idade , Boca/patologia , Neoplasias Bucais/virologia , Infecções por Polyomavirus/complicações , Estudos Prospectivos , Adulto JovemRESUMO
AIMS: Inflammatory myofibroblastic tumours (IMTs) usually have a soft tissue and visceral localization, but have been rarely reported in skin. The aim of this study was to characterize the histological and immunohistochemical features of a series of cutaneous IMTs. METHODS AND RESULTS: We retrieved from our archives over 10 years four cutaneous IMTs; one was diagnosed in a child, and three in young adults. Tumours were centred on the dermis, and also involved the subcutis in two cases. Two of them corresponded to the 'myxoid-vascular' pattern of IMT, whereas the others were characterized by compact fascicles of spindle-shaped cells. They stained positively for smooth muscle actin. All samples stained positively for anaplastic lymphoma kinase (ALK). ALK expression was limited to the cytoplasm of myofibroblasts and, in the three investigated cases, correlated with ALK rearrangement as shown by fluorescence in-situ hybridization analysis. CONCLUSIONS: This is the first report of ALK-positive IMTs with a cutaneous localization. Because of their morphological heterogeneity and low incidence in skin, the diagnosis of cutaneous IMTs is often challenging. A cutaneous spindled cell tumour associated with an inflammatory infiltrate should prompt pathologists to perform ALK staining, which, if positive, might be decisive for diagnosis.
Assuntos
Biomarcadores Tumorais/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Neoplasias Cutâneas/diagnóstico , Actinas/análise , Adulto , Quinase do Linfoma Anaplásico , Criança , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Miofibroblastos/patologia , Proteínas Tirosina Quinases/biossíntese , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: Telangiectasia macularis eruptiva perstans (TMEP) has not been fully characterized. OBJECTIVE: We sought to estimate the frequency and clinical characteristics of TMEP in a cohort of adult patients with cutaneous mastocytosis, and to assess the presence of systemic involvement. METHODS: We included all consecutive patients evaluated for cutaneous mastocytosis in 2 centers: the Mastocytosis Competence Center of the Midi-Pyrénées from May 2006 to December 2013, and the French Reference Center for Mastocytosis from January 2008 to September 2013. Skin phenotype, histopathology, presence of KIT mutation in the skin, and assessment of systemic involvement according to World Health Organization (WHO) criteria were prospectively investigated. RESULTS: Of 243 patients with cutaneous mastocytosis, 34 (14%) were given a diagnosis of TMEP. The diagnosis of systemic mastocytosis was established in 16 patients (47%) with TMEP. Three patients (9%) had aggressive systemic mastocytosis (C-findings according to WHO). In all, 32 patients (94%) exhibited at least 1 mast cell activation-related symptom. LIMITATIONS: Patient recruitment was undertaken at 2 referral centers with expertise in the diagnosis and treatment of mastocytosis so that the clinical findings and incidence of systemic involvement may be overestimated in comparison with the overall population of patients with TMEP. CONCLUSION: TMEP accounts for about 14% of patients with cutaneous mastocytosis. The disease manifests as mast cell activation symptoms in almost all patients and can be associated with systemic involvement in about 50% of cases.
Assuntos
Mastocitose Sistêmica/patologia , Telangiectasia/patologia , Urticaria Pigmentosa/patologia , Adulto , Fatores Etários , Biópsia por Agulha , Estudos de Coortes , Progressão da Doença , Feminino , França , Testes Hematológicos , Humanos , Imuno-Histoquímica , Masculino , Mastocitose Sistêmica/epidemiologia , Mastocitose Sistêmica/fisiopatologia , Pessoa de Meia-Idade , Prognóstico , Encaminhamento e Consulta , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Telangiectasia/fisiopatologia , Urticaria Pigmentosa/epidemiologia , Urticaria Pigmentosa/fisiopatologiaRESUMO
This study tested the sensitivity and specificity of VE1 antibody raised against BRAFV600E protein, on 189 melanoma samples, compared with molecular testing. In addition, the therapeutic response to BRAF inhibitors was analysed in 27 patients, according to staining intensity (scored from weak to strong) and pattern (homogeneous or heterogeneous). BRAFV600E status during melanoma progression was evaluated in a cohort of 54 patients with at least paired-samples. High sensitivity (98.6%) and specificity (97.7%) of VE1 were confirmed. During melanoma progression different samples showed concordant phenotypes. Heterogeneous VE1 staining was observed in 28.5% of cases, and progression-free survival was higher in patients with tumour samples displaying such staining. These findings suggest that only VE1-negative tumours would be genotyped to detect other BRAFV600 mutations, and that either primary melanoma or metastasis can be tested using immunohistochemistry, according to the material available.
Assuntos
Melanoma/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Anticorpos Monoclonais , Biomarcadores Tumorais/análise , Análise Mutacional de DNA , Progressão da Doença , Genótipo , Humanos , Imuno-Histoquímica , Melanoma/tratamento farmacológico , Melanoma/patologia , Metástase Neoplásica , Fenótipo , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologiaRESUMO
No specific biomarkers for prognostication or evaluation of tumour load in melanoma have been reported to our knowledge. MicroRNAs (miRNAs) are strongly implicated in oncogenesis and tumour progression, and their circulating forms have been studied as potential biomarkers in oncology. The aim of this prospective study was to identify a melanoma-specific profile of plasma miRNAs. A screening phase, using RNA microarray, was conducted on plasma from 14 patients with metastatic melanoma and 5 healthy subjects. Selected miRNAs were analysed by RTqPCR in 2 independent training and validation cohorts including, respectively, 29 and 31 patients and 16 and 43 control subjects. A profile of 2 miRNAs (miR-1246 and miR-185) significantly associated with metastatic melanoma with a sensitivity of 90.5% and a specificity of 89.1% was identified. This plasma miRNA profile may become an accurate non-invasive biomarker for melanoma.
Assuntos
Biomarcadores Tumorais/sangue , Perfilação da Expressão Gênica , Melanoma/sangue , MicroRNAs/sangue , Neoplasias Cutâneas/sangue , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Perfilação da Expressão Gênica/métodos , Humanos , Melanoma/genética , Melanoma/secundário , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologiaRESUMO
Overlap chronic graft-versus-host disease (GVHD) associates both features of acute and chronic GVHD. Trigger factors for chronic GVHD are unclear. We describe two patients who received allogenic haematopoietic stem-cell transplantation, and who later developed overlap chronic GVHD after sun exposure. Available data from in vivo investigations suggest ultraviolet B radiation (UVB) has a beneficial effect on acute and chronic GVHD. The role of sun irradiation as a trigger for isomorphic cutaneous GVHD has been rarely reported in the literature. Herein, we demonstrate for the first time, using repetitive broadband phototesting, that UVB triggers chronic GVHD.