Search Results (143)

Photodynamic therapy (PDT) has become a widely used modality for treating actinic keratosis (AK) and non-melanoma skin cancers (NMSC), as well as other inflammatory or infectious diseases. Despite its efficacy, limitations such as incomplete responses and pain have motivated the exploration of protocol enhancements. This review examines the clinical and biological rationale for light fractionation—dividing the total light dose into two separate exposures with a dark interval—as a strategy to improve PDT outcomes. We reviewed preclinical and clinical studies evaluating fractionated illumination using 5-aminolevulinic acid (ALA) or methyl aminolevulinate (MAL). The findings consistently demonstrate superior efficacy of fractionated schemes, particularly with ALA, showing higher complete response rates in AK, superficial basal cell carcinoma (sBCC), and Bowen’s disease (BD), and improved long-term tumor control compared to single illumination. The better outcomes are attributed to increased reactive oxygen species (ROS) generation following tissue reoxygenation during the dark interval and greater susceptibility of partially damaged cells to subsequent illumination. Fractionated PDT also shows a favorable safety and cosmetic profile. These results support considering light fractionation protocols as a standard approach for optimizing PDT efficacy in dermatologic oncology, particularly in lesions with limited depth and high recurrence risk. Full article

Background: The relationship between occupational sun exposure and melanoma risk is complex and multifaceted, with existing evidence yielding contradictory findings. Unlike Non-Melanoma Skin Cancer (NMSC), for which occupational sun exposure is a well-established risk factor, the link with cutaneous melanoma remains contentious. Objectives: This study aimed to evaluate whether, in a cohort of patients with cutaneous melanoma, an association existed between occupational sun exposure and melanoma, specifically with histotype, site of occurrence, and Breslow index. Methods: This is a retrospective cohort analysis conducted to evaluate whether occupational sun exposure constitutes a risk factor for the development of cutaneous melanoma in patients diagnosed between January 2005 and October 2023 at the Dermatology Unit, Azienda USL Toscana Centro, Florence. Occupational ultraviolet (UV) exposure was examined by classifying each participant’s job into categories based on solar UV exposure levels—outdoor (e.g., agriculture and construction roles), mixed indoor/outdoor (e.g., trades and public safety professions), and indoor settings (e.g., office-based work). Results: A final total of 1417 patients were analyzed. Occupational categorization revealed that 1171 patients (82.64%) were classified as non-occupationally exposed (indoor), while 246 (17.36%) were occupationally exposed to solar UV radiation (including 14.82% mixed indoor/outdoor and 2.54% outdoor workers). A significant association was observed between occupational sun exposure and lentigo maligna, which was more prevalent among exposed workers and even more so in the outdoor subgroup. Anatomical site distribution exhibited a significant association with occupational sun exposure. Indeed occupationally exposed individuals showed a higher prevalence of melanomas in the head and neck region, a distribution pattern particularly evident among outdoor workers, suggesting that these sites may be more susceptible to chronic sun exposure in outdoor and mixed occupations. Moreover, a significant association was found between occupational exposure and Breslow thickness, with exposed workers presenting with thicker melanomas at diagnosis, suggesting more advanced disease. Conclusions: The finding of this study may reflect variations in occupational sun exposure patterns and warrants further investigation into protective measures and early-detection strategies tailored to occupational groups. Full article

Background: Merkel cell polyomavirus (MCPyV) has been established as an etiological agent in Merkel cell carcinoma (MCC), yet its role in other cutaneous neoplasms remains under investigation. The impact of the host’s immunogenetic characteristics on the persistence of Merkel cell polyomavirus (MCPyV) in non-melanoma skin cancer (NMSC) is not yet well understood. Objective: Our aim was to investigate the presence of MCPyV in various skin lesions, particularly NMSC, and its association with cytokine gene polymorphisms related to immune regulation. Methods: We analyzed 274 skin biopsies (lesional, perilesional, and healthy skin) from 84 patients undergoing dermatological evaluation. MCPyV DNA and polymorphisms in IL-6, IL-10, IFN-γ, and TNF-α genes were detected using PCR-based assays. Results: MCPyV was significantly more prevalent in NMSC and non-cancerous lesions than in surgical margins or healthy skin (p = 0.050 and 0.048, respectively). Concordance between lesion and margin samples was low (κ = 0.305), suggesting microenvironment-specific viral persistence. Notably, high-expression IL-10 genotypes (-1082 GG) and low-expression IL-6 genotypes (-174 AA) were significantly associated with MCPyV detection (p = 0.048 and p = 0.015, respectively). Conclusions: MCPyV preferentially localizes to NMSC lesions, particularly in individuals with immunogenetic profiles favoring viral persistence. Since the role of MCPyV in the pathogenesis of NMSC remains uncertain, our results highlight the need for further studies to clarify whether the lesion’s microenvironment supports viral persistence or indicates a more intricate interaction between the virus and the host, which could be significant for the development of skin cancer. Full article

Non-melanoma skin cancer (NMSC), comprising basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), represents the most common type of cancer worldwide, particularly among Caucasians. While BCC is locally invasive with minimal metastatic potential, cSCC is a highly aggressive tumor with a significant potential for metastasis, particularly in elderly populations. Tumor development and progression and the metastasis of cSCC are influenced by a complex interplay between tumor cells and the tumor microenvironment. Recent research highlights the importance of various immune cell subsets, including T cells, tumor-associated macrophages (TAMs), and dendritic cells, in influencing tumor progression, immune evasion, and treatment resistance. This review outlines key regulatory mechanisms in the immune tumor microenvironment (TME) of cSCC and explores the role of cytokines, immune checkpoints, and stromal interactions. We further discuss the relevance of three-dimensional (3D) in vitro models such as spheroids, organoids, and tumor-on-chip systems as tools to mimic immune–tumor interactions with higher physiological relevance, such as macrophage activation and polarization against cSCC cells. Globally, 3D models offer new opportunities for immunotherapy screening and mechanistic studies. Understanding the immune landscape in cSCC through advanced modeling techniques holds strong clinical potential for improving diagnostic and therapeutic strategies. Full article

This narrative review examines the efficacy, cost-effectiveness, and aesthetic outcomes of Mohs micrographic surgery (MMS) compared to standard excision for treating non-melanoma skin cancers (NMSCs). A comprehensive literature search was conducted across multiple databases, including PubMed, Scopus, and Cochrane Library, covering studies published from 2000 to 2024. Key terms such as “Mohs Micrographic Surgery,” “non-melanoma skin cancer,” “recurrence rates,” “cost-effectiveness,” and “aesthetic outcomes” were utilized. Inclusion criteria encompassed peer-reviewed articles, clinical trials, and observational studies focusing on MMS and standard excision outcomes. Exclusion criteria included studies with inadequate data or those not published in English. The review highlights the superior oncologic outcomes of MMS, its cost-effectiveness over the long term, and comparable aesthetic results to standard excision principally. Methods: This narrative review was conducted following established guidelines for reporting narrative reviews. A systematic search strategy was employed across selected databases, with the last search conducted in May 2025. The search terms used were “Mohs Micrographic Surgery,” “non-melanoma skin cancer,” “recurrence rates,” “cost-effectiveness,” and “aesthetic outcomes.” Studies included were published between 2000 and 2024, in English, and provided data on the specified outcomes. Results: The majority of studies indicated that MMS offers superior recurrence-free survival rates compared to standard excision. Regarding cost-effectiveness, MMS was found to be more economical over the long term due to reduced recurrence rates and the need for fewer re-excisions. Aesthetic outcomes were comparable between MMS and standard excision, with both methods yielding satisfactory results. Discussion: The findings of this review support the use of MMS as a preferred treatment for high-risk NMSCs, particularly in cosmetically sensitive areas. While MMS may involve higher initial costs, its long-term cost-effectiveness and superior oncologic outcomes justify its use. The aesthetic outcomes associated with MMS are comparable to those of standard excision, making it a viable option for patients concerned with cosmetic results. Limitations: This review acknowledges several limitations, including the heterogeneity of study designs and potential selection biases inherent in the included studies. Additionally, the absence of randomized controlled trials comparing MMS and standard excision directly limits the strength of the conclusions drawn. Conclusions: This narrative review underscores the advantages of MMS in treating high-risk NMSCs, particularly in terms of recurrence rates and long-term cost-effectiveness. While both MMS and standard excision offer comparable aesthetic outcomes, the superior oncologic results of MMS make it a preferable option in certain clinical scenarios. Full article

Background: Basal cell carcinoma (BCC) is the most common skin cancer worldwide, with a multifactorial aetiology involving environmental and intrinsic factors. A small subset of patients develops high-frequency BCC (HF-BCC), defined as ≥9 BCCs within 3 years. Objective: To analyse demographic, clinical, and histopathological features of non-syndromic HF-BCC in a Belgian cohort, compared with low-burden BCC patients and healthy controls. Methods: A retrospective cohort study was conducted at Erasme Hospital (Brussels) using data from the EUSCAP platform. Clinical, behavioural, and histopathological data were collected and statistically analysed. Results: Of 783 patients, 16 with HF-BCC were identified. For comparison, 32 patients with 1–2 BCCs and 117 patients without BCC were selected. HF-BCC patients showed distinct characteristics, including a higher proportion of superficial BCCs (68.3% vs. 50%, p = 0.01) and fewer nodular subtypes (43.2% vs. 63.5%, p = 0.01). Their tumours were less frequently located on the nose and ears compared with patients having 1–2 BCCs. HF-BCC was associated with a personal history of squamous cell carcinoma (SCC) and actinic keratosis (AK). Conclusions: HF-BCC patients display distinct anatomical, histopathological and clinical characteristics, with a predominance of superficial BCC and an association with a personal history of SCC and AK. They show a lower frequency of tumours on the nose and ears, with a stronger tendency for localisation on the trunk and extremities. Identifying risk factors and genetic markers may contribute to improved early detection strategies, preventive measures, and the development of targeted therapies. Full article

Background/Objectives: Non-melanoma skin cancer (NMSC) is among the most common cancers in the United States, with solar ultraviolet (UV) radiation being a primary etiological factor. T-LAK cell-originated protein kinase (TOPK), a serine/threonine kinase activated by solar UV, has been implicated in skin carcinogenesis. This study aimed to investigate the mechanistic role of TOPK in solar UV-induced skin damage and tumor development. Methods: RNA sequencing (RNA-seq) was performed on skin tissues from wild-type (WT) and TOPK knockout (KO) mice, with or without solar UV exposure, to identify TOPK-regulated genes and pathways. Follow-up experiments using Western blotting, immunofluorescence, and luciferase assays were conducted in vitro and in vivo. Functional assays included 3D spheroid and Transwell co-culture systems involving cutaneous squamous cell carcinoma (cSCC) and fibroblast cells. Results: TOPK deletion altered gene expression profiles and inhibited solar UV-induced activation of multiple signaling pathways, including cytokine–cytokine receptor interaction, PI3K/AKT, MAPKs, PKG, cAMP, and calcium signaling. RNA-seq and protein analyses identified interleukin-19 (IL19) as a key downstream effector suppressed by TOPK deletion. In cSCC and fibroblast cells, TOPK knockdown reduced IL19 expression and secretion. IL19 promoted cSCC growth and activated PI3K/AKT, ERK, and TOPK pathways. Additionally, chronic TGFβ exposure increased IL19 expression and activated fibroblasts, as indicated by elevated αSMA and FAPα levels. Conclusions: These findings establish TOPK as a central regulator of solar UV-induced skin carcinogenesis, partially via modulation of IL19 signaling and fibroblast activation. Targeting TOPK may offer a novel strategy for the prevention and treatment of NMSC. Full article

Introduction: The introduction of biologic therapies and small molecule drugs has revolutionized the management of inflammatory bowel disease (IBD), providing targeted control of inflammation. However, concerns remain regarding their long-term safety profiles, particularly in relation to cancer risk. Chronic inflammation and immunosuppressive therapies contribute to malignancy risk, including skin cancers, such as melanoma and non-melanoma skin cancer (NMSC). This review examines the evidence on skin cancer risks associated with these therapies, focusing on specific drug classes and their mechanisms. Results: Tumor necrosis factor (TNF) inhibitors have shown conflicting evidence regarding melanoma risk, with some studies reporting a modest increase and others finding no significant association. Anti-integrin agents, such as vedolizumab, and interleukin (IL)-12/23 inhibitors, including ustekinumab, have demonstrated favorable safety profiles with minimal skin cancer risks. Selective IL-23 inhibitors and sphingosine-1-phosphate (S1P) receptor modulators have limited long-term data, but early findings indicate a low incidence of skin malignancies. Janus kinase (JAK) inhibitors do not show an increased risk of skin cancers in IBD. Conclusions: Current evidence suggests that skin cancer risk in IBD patients treated with biologics and small molecule drugs varies by drug class. TNF inhibitors and JAK inhibitors are associated with higher risks, while other therapies show lower malignancy risks. Regular skin cancer screening and protective measures remain critical, particularly for patients with additional risk factors. Further long-term studies are essential to refine safety profiles and inform clinical practice in this evolving therapeutic landscape. Full article

Background: Studies on somatic mutations in cancer typically report single-nucleotide variants in coding regions, while mutations in short tandem repeats (STRs) are usually overlooked. Homopolymeric regions, a subset of STRs, are stretches of DNA where only a single nucleotide is repeated multiple times (e.g., AAAAA or TTTTT). Only recently have mutations in such STR regions been seen in colorectal cancer, where microsatellite instability (MSI) is common. In non-melanoma skin cancer (NMSC), MSI is rare. In this study, we focus on somatic mutations in such homopolymeric regions in NMSC and their functional implications. Methods: We performed targeted DNA sequencing (paired tissue and blood from the same individual), using more than 400 cancer-related genes from 32 NMSC patients as cases and non-lesional skin tissue from 16 independent individuals as controls. Results: We identified NMSC-associated STR somatic mutations. These are associated with the dysregulation of DNA damage and repair mechanisms. In artificial intelligence (AI) predictive modeling, these markers could successfully differentiate basal cell carcinoma (BCC) and non-lesional skin tissue. To our knowledge, we present the first study focusing on STR somatic mutations in multiple cancer-related genes in NMSC found only in tumor tissue and not in non-lesional skin tissue. Some of them (APC, BRAF) are associated with more pronounced dysregulation of relevant gene pathways (hedgehog, Notch signaling, and Wnt signaling). Conclusions: Our findings suggest that this STR somatic mutation status might potentially be used to select BCC patients who could benefit from certain precision therapy including hedgehog inhibitors, gamma-secretase inhibitors, anti-Vasuclar endothelial growth factor (VEGF), proteasome inhibitors, and immune check-point inhibitors. Full article

Hydroxyurea (HU), a cornerstone treatment for myeloproliferative disorders, is associated with a wide range of cutaneous side effects, from xerosis and hyperpigmentation to more severe conditions like dermatomyositis-like eruptions (DM-LE) and nonmelanoma skin cancers (NMSC), particularly squamous cell carcinoma (SCC). In this review, we present a unique case of HU-induced DM-LE with histological evidence of keratinocyte dysplasia and p53 overexpression, followed by a systematic analysis of similar cases. Our findings reveal that the clinical presentation of DM-LE, while typically considered benign, shares clinical and histological features with hydroxyurea-associated squamous dysplasia (HUSD), a precancerous condition that may progress to SCC in chronically exposed patients. Key insights include the characteristic histopathological findings of DM-LE, the role of chronic HU therapy and UV-induced damage in promoting p53 overexpression, and the overlap between DM-LE and HUSD. Regular dermatologic monitoring, patient education on photoprotection, and the careful assessment of skin lesions in long-term HU users are essential for the early detection and prevention of malignancies. This review underscores the importance of distinguishing between DM-LE, HUSD, and SCC to optimize management and minimize risks associated with HU therapy. Full article

The emergence of systemic therapies and photoprotection against non-melanoma skin cancer (NMSC) raises questions on the broader systematic impact of the disease. Personalized medicine involves a holistic patient approach, through which the evaluation of systemic biomarkers can reveal the interconnected aspects of patient health and tailored therapies. Cumulative UV exposure disrupts redox equilibrium and triggers inflammation and cutaneous immunosuppression, processes that contribute independently or via their interplay to cutaneous carcinogenesis. This systemic impact can be further reinforced by biomolecules derived from the NMSC microenvironment, fueling a continuous cycle of oxidative stress and inflammation in the organism. Regarding investigation of the systemic burden of NMSC, we conducted a narrative review focusing on parameters related to redox status, inflammation, and immune suppression observed in the blood components (serum, plasma, and erythrocytes) of NMSC patients. Our findings revealed an association of NMSC patients with perturbations of redox homeostasis, as evidenced by the decreased antioxidant activity, lower levels of non-enzymatic antioxidants, and increased byproducts of lipid, protein, and DNA oxidative damage. Additionally, NMSC patients presented augmented levels of pro-inflammatory interleukins, reduced anti-tumor biomolecule levels, and enhanced immune response markers, as well as elevated vitamin D levels. These systemic changes may lead to the association of NMSC with a higher risk of secondary malignancies in other organs. Overall, the findings of the present study suggest that NMSC affects systemic health beyond the skin, underscoring the need for a comprehensive and individualized approach to the management and monitoring of the patient. Full article

Arsenic (As) is a risk factor for non-melanoma skin cancer (NMSC). From a six-year follow-up study on 7000 adults exposed to As, we reported the associations of single-nucleotide variation in tumor tissue and gene expression. Here, we identify the associations of small deletions (DELs) and transcriptomic profiles in NMSC. Comparing the (a) NMSC tissue (n = 32) and corresponding blood samples from each patient, and (b) an independent set of non-lesional, healthy skin (n = 16) and paired blood, we identified NMSC-associated DELs. Differential expressions of certain gene pathways (TGF-β signaling pathway, IL-17 pathway, PD-L1 pathway, etc.) showed significant interactions with these somatic DELs and As exposure. In low-As-exposure cases, the DELs in APC were associated with the up-regulation of inflamed T-Cell-associated genes by a fold change (FC) of 8.9 (95% CI 4.5–17.6), compared to 5.7 (95% CI 2.9–10.8) without APC DELs; in high-As-exposure cases, the APC DELs were associated with an FC of 5.8 (95% CI 3.5–9.8) compared to 1.2 (95% CI −1.3 to 1.8) without APC DELs. We report, for the first time, the significant associations of somatic DELs (many in STR regions) in NMSC tissue and As exposure with many dysregulated gene pathways. These findings may help in selecting groups of patients for potential targeted therapy like PD-L1 inhibitors, IL-17 inhibitors, and TGF-β inhibitors in the future. Full article

Background/Objectives: Sentinel Lymph Node Biopsy (SLNB) aims at identifying clinically occult nodal metastases. It is the standard staging procedure for patients with T1b to T4 primary cutaneous melanoma. Moreover, it is recommended whenever the risk of a positive SLNB is >5%, according to the National Comprehensive Cancer Network Melanoma guidelines. When considering Non-Melanoma Skin Cancer (NMSC), the SLNB could play a role in tumors that mainly spreads via lymphatics, but strong evidence is missing. In this paper, the hot topics and controversies are reviewed; Methods: A PRISMA systematic review was carried out on the PubMed (MEDLINE) library from 2004–2024, searching for studies on SLNB in NMSC; Results: Seventy articles and 6379 patients undergoing SLNB for Squamous Cell Carcinoma (SCC), Merkel Cell Carcinoma (MCC), and Porocarcinoma were included. Overall, the SLNB positivity rate in these NMSCs was 24.4%, with an SNLB detection rate of 97.6%. Specifically, the SLNB positivity rate was 12.3% for high-risk cutaneous SCC, 24.4% for anogenital SCC, 29.3% for MCC, and 30.6% for Porocarcinoma. Most papers concluded that SLNB is safe, feasible, and significant in these malignancies; Conclusions: SLNB should be discussed and offered to every patient with MCC, and it should be discussed and considered in “high risk” SCC and Porocarcinoma for staging and prognostic purposes, aiming to identify a subgroup of patients who may benefit the most from early treatments. Full article

Background: This study aimed to explore the relationship between different types of skin cancer and factors such as sun exposure and photoprotection measures in a Greek cohort on the island of Crete. Methods: This cross-sectional observational study was conducted in the Dermatology Department of the University Hospital in Heraklion, Crete, between January 2019 and January 2024. The study population included consecutive patients diagnosed with basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and malignant melanoma (MM), as well as healthy controls. The participants completed a self-reported questionnaire covering demographic and clinical data as well as questions about sun exposure and photoprotection habits. Results: A total of 265 skin cancer patients and 106 healthy controls participated in the study: 50.6% of the patients had basal cell carcinoma, 35.1% had squamous cell carcinoma, and 14.3% had malignant melanoma. The cohort comprised 41.5% females and 58.5% males, with a mean age of 73.2 years. As expected, the patients with skin cancer had a lighter skin phototype compared to the healthy controls (p < 0.01). They also reported greater occupational (p < 0.01) and leisure sun exposure (p < 0.01) and a higher median number of vacation weeks spent outdoors before the age of 18 (p = 0.030). Furthermore, the healthy controls were more likely to use sunscreen (p = 0.035) and preferred higher SPF (>50) when they did so (p < 0.01). The healthy controls also reported more frequent use of sunglasses (p < 0.01), brimmed hats (p < 0.01), and long-sleeved clothing (p < 0.01) compared to the skin cancer patients. Conclusion: This is the first study to analyze sun exposure and photoprotection behaviors in patients with nonmelanoma skin cancer (NMSC) and malignant melanoma (MM) in Crete, revealing the key associations and underscoring the need for targeted prevention strategies. Full article

Background/Objective: Ultraviolet (UV) B radiation leads to DNA damage by generating cyclobutane pyrimidine dimers (CPDs). UVB-induced CPDs can also result in immune suppression, which is a major risk factor for non-melanoma skin cancer (NMSC). UVB-induced CPDs are repaired by nucleotide repair mechanisms (NER) mediated by xeroderma pigmentosum complementation group A (XPA). The purpose of this study was to investigate the use of TH as a chemopreventive agent against the development of skin cancer. Method: SKH-1 hairless mice were exposed were fed with TH (0.1% v/v) for two weeks and exposed to a single dose of UVB (180 mJ/cm²). Dorsal skin was harvested 24 h post-UVB exposure for evaluation of DNA damage and repair. Lymph nodes were also harvested to prepare single cell suspension for flow cytometric evaluation. For carcinogenesis experiments, SKH-1 hairless mice were given TH (0.1% v/v) ad libitum and exposed to UVB (180 mJ/cm²) thrice a week for 30 weeks. Results: Feeding SKH-1 hairless mice with TH (0.1% v/v) for two weeks prior to a single dose of UVB (180 mJ/cm²) led to a significant increase in XPA in skin and DNA repair cytokines IL-12 and IL-23 in draining lymph nodes. Furthermore, when subjected to the photocarcinogenesis protocol; mice fed with TH developed significantly fewer tumors in comparison to mice fed on drinking water. Conclusions: Our data demonstrate that TH has a protective effect against UVB-induced DNA damage, immune suppression, and skin cancer. Future studies will further investigate the potential of TH as a preventive treatment for NMSC. Full article