European interdisciplinary guideline on invasive squamous cell carcinoma of the skin: Part 1. epidemiology, diagnostics and prevention

Risk factors for incomplete excision of cutaneous squamous cell carcinoma: A single-center study performed on 1082 excisions in Northern Italy

Cutaneous squamous cell carcinoma, which makes up for 25% of keratinocyte carcinomas, is the second most frequent skin cancer worldwide. Surgical excision via a clinical and microscopic complete resection is the treatment of choice. Incomplete excisions carry the risk of local recurrence, deep subclinical progression, and metastasis. This retrospective cohort study aimed to investigate the risk factors associated with the incomplete excision of cutaneous squamous cell carcinoma. This series included 837 patients who underwent surgical treatment for 1082 primary cutaneous squamous cell carcinoma in the Plastic Surgery Department of the Papa Giovanni XXIII Hospital in Bergamo, Northern Italy between 2012 and 2021. Patient-, procedure-, and tumor characteristics were collected and analyzed. Incomplete excision rate was 11.8% (n=128). The Pearson chi-squared test and univariable logistic regression showed tumor diameter [cm] (p<0.001), tumor thickness [mm] (p<0.001), tumor location (ear p=0.006, peri-orbital, p=0.029), differentiation grade (G3=0.005), infiltration level (hypodermis, p<0.001; muscle, p=0.013; bone/ cartilage p<0.001), presence of perineural invasion (p=0.041), ulceration (p=0.010), no prior diagnostic biopsy (p=0.041), and additional samples taken (p<0.001) with additional samples not free of tumor cells (p<0.001) to be significant risk factors/ predictors for incomplete excision. Risk factors should be considered in the management of cutaneous squamous cell carcinoma. This study documented several key contributions and confirmations regarding the risk factors associated with incomplete excision in cutaneous squamous cell carcinoma by comprehensively analyzing of one of the largest cohort studies in the field.

Sunscreen and 25-hydroxyvitamin D vitamin D levels: friends or foes? Systematic review and meta-analysis

OBJECTIVE

To evaluate the impact of sunscreen use on 25-hydroxyvitamin D (25(OH)D) levels, addressing conflicting findings from observational and interventional studies.

METHODS

Potentially eligible studies were identified from the PubMed/MEDLINE, Scopus and Web of Science databases from inception to November 2024, utilizing a search strategy incorporating terms related to "sunscreen" and "vitamin D". The studies eligible addressed the questions define based on the PICO framework: What are 25(OH)D levels in patients exposing to sun applying or not sunscreen? This review followed PRISMA guidelines. The quality assessment and the risk of bias were analyzed using QUADAS-2.

RESULTS

We included 22 studies in the qualitative synthesis, and 7 in the quantitative one, encompassing a total of 9,470 participants. In vitro studies consistently showed that sunscreen blocks UVB radiation, crucial for vitamin D3 production, while population-based studies reported mixed findings. Some studies linked sunscreen use to lower 25(OH)D levels, particularly in individuals with limited sun exposure, while others observed no significant impact. Meta-analysis showed that that the adoption of sunscreen is associated to a reduction of 25(OH)D serum concentration (SMD=-2 ng/mL, 95% C.I. -3, -1) with a not important heterogeneity across studies (I2 =37%, p=0.15) CONCLUSION: The existing evidence supports that sunscreen can impair vitamin D3 synthesis, and as a result decrease serum 25(OH)D levels, but further research is necessary to determine the broader health implications and guide public health recommendations.

Dissolving microneedles for melanoma: Most recent updates, challenges, and future perspectives

Skin cancer is one among the common types of cancers, affecting millions of individual globally. The conventional anticancer therapy such as chemotherapy results in worst systemic and local side effects as well as inhibit the growth of healthy cells around the tumor cells. Dissolving microneedles (DMNs) is a groundbreaking technology with less invasive and more targeted features. Physically, these tiny dissolving needles deliver the anticancer payloads drug to the tumor site after its direct application on the skin surface. Specifically, the DMNs release the anticancer drug cargoes into the cancerous cell sparing the healthy cells around the tumor, thus has provided a significant contribution in the landscape of traditional skin cancer therapy. This targeted therapeutic approach of dissolving microneedles shows a significant therapeutic outcome in decreasing the growth of cancer cells in pre-clinical studies. Dissolving microneedles (DMNs) have demonstrated effectiveness in the targeted delivery of drugs, genes, and vaccines specifically at the site of skin tumors. This method mimics the localized release of adjuvants and immunomodulators, leading to significant humoral and cellular immune responses that are beneficial for skin cancer therapy. In this review, the current trends and potential roles of dissolving microneedles in delivering therapeutic agents focused on treating skin melanoma have been highlighted, drawing insights from recent literature. This emphasizes the promising applications of DMNs in enhancing treatment outcomes for skin cancer patients. Lastly, future perspectives were identified for improving the therapeutic potential and translation of DMNs into clinic.

Ultrasound Characteristics of Keratoacanthoma: Differentiation From Well-Differentiated Cutaneous Squamous Cell Carcinoma

OBJECTIVE

This study aims to describe the ultrasound characteristics of keratoacanthoma (KA), providing valuable insights for non-invasive diagnosis and differentiation from well-differentiated cutaneous squamous cell carcinoma (wcSCC).

METHODS

Ultrasound characteristics of 16 KA and 13 wcSCC conformed by surgical pathology were retrospective analyzed.

RESULTS

KA patients were younger (mean age 63.13 years) compared with wcSCC patients (mean age 76.23 years). Ultrasound characteristics revealed that KA lesions were generally smaller, more frequently domed-shaped (87.50 vs 38.46%), exophytic (93.75 vs 30.77%), and well-defined (93.75 vs 53.85%) compared with wcSCC. Both lesion types predominantly showed hypoechoic internal echoes and inhomogeneous echotexture. The prevalence of hyperechoic superficial area was notably high in both groups (93.75 vs 84.62%), precluding the reliable use of this feature as a discriminatory marker between these two distinct neoplastic entities. KA lesions were mostly confined to the epidermis and superficial dermis (87.50%), while wcSCC cases frequently infiltrated into the subcutaneous fat layer (84.62%). Color Doppler imaging demonstrated higher vascularity in wcSCC lesions, with 61.5% showing Grade 3 flow, compared with KA lesions, where 62.5% exhibited Grade 2 flow.

CONCLUSIONS

High-frequency ultrasound reveals distinct ultrasound characteristics differentiating KA from wcSCC, offering a promising non-invasive tool for preliminary diagnosis and treatment planning.

Long-Term Data From Patients Who Received Pembrolizumab in Locally Advanced or Metastatic Cutaneous Squamous Cell Carcinoma

Nonmelanoma skin cancer (NMSC) is one of the most common cancers worldwide and cutaneous squamous cell carcinoma (CSCC) is the second most prevalent type of the NMSCs. Most often, the prognosis is good when treated with surgery with or without additional radiotherapy; however, in about 1% of patients, the disease is inoperable or advanced with no curative potential. We present four cases in which the immune checkpoint inhibitor pembrolizumab was given to patients with advanced CSCC. Three patients obtained complete response (CR) with an ongoing duration of response with a follow-up time of 60, 78, and 79 months and one who achieved stable disease (SD) as the best response. Two of the patients discontinued treatment after eight cycles of pembrolizumab due to side effects. Immunotherapy with a programmed death protein 1 (PD-1) inhibitor is an approved therapy for these patients today. The successful treatment with long-term duration of response of these three out of four patients supports the use of a PD-1 inhibitor as a primary treatment for locally advanced and metastatic CSCC.

From actinic keratosis to cutaneous squamous cell carcinoma: the key pathogenesis and treatments

Cutaneous squamous cell carcinoma (cSCC) is the second most common non-melanoma skin cancer, among which 82% arise from actinic keratosis (AK) characterized by lesions of epidermal keratinocyte dysplasia. It is of great significance to uncover the progression mechanisms from AK to cSCC, which will facilitate the early therapeutic intervention of AK before malignant transformation. Thus, more and more studies are trying to ascertain the potential transformation mechanisms through multi-omics, including genetics, transcriptomics, and epigenetics. In this review, we gave an overview of the specific biomarkers and signaling pathways that may be involved in the pathogenesis from AK to cSCC, pointing out future possible molecular therapies for the early intervention of AK and cSCC. We also discussed current interventions on AK and cSCC, together with future perspectives.

Histopathological Diagnostic Discordance between Punch Biopsies and Final Diagnostic Excisions of Cutaneous Squamous Cell Carcinoma: Analysis of 737 Cases

The recommended treatment for cutaneous squamous cell carcinoma is surgical excision. An initial punch biopsy is often performed as an aid to diagnosis. A retrospective registry-based study was performed to assess histopathological concordance of punch biopsy of cutaneous squamous cell carcinoma and subsequent excision. Analysis of 737 punch biopsies and subsequent matched excisions was performed. In total, 493 (67%) lesions were confirmed as invasive cutaneous squamous cell carcinoma on excision, 76% when excluding "scar" as a final diagnosis. Tumour diameter > 20mm was highly predictive of cutaneous squamous cell carcinoma (positive predictive value 91.1%). Tumours on the scalp were significantly more likely to demonstrate a final diagnosis of cutaneous squamous cell carcinoma than those on the arm (odds ratio 6.11, 95% confidence interval 3.1,12.0). There was moderate concordance between biopsy and excision in grade of histopathological differentiation. This study demonstrates that clinical high-risk features may be of more value in predicting a diagnosis of cutaneous squamous cell carcinoma than partial punch biopsy. Use of clinical and dermoscopic competencies in assessment of cutaneous tumours rather than reliance on biopsies both avoids delay in patient management in the case of high-risk cutaneous squamous cell carcinoma and may also minimize unnecessary surgical excisions if there is a low clinical index of suspicion of cutaneous squamous cell carcinoma.

A phase 2 open-label study of cemiplimab in patients with advanced cutaneous squamous cell carcinoma (EMPOWER-CSCC-1): Final long-term analysis of groups 1, 2, and 3, and primary analysis of fixed-dose treatment group 6

BACKGROUND

In the phase 2 EMPOWER-CSCC-1 study (NCT02760498), cemiplimab demonstrated antitumor activity against metastatic cutaneous squamous cell carcinoma (mCSCC) and locally advanced cutaneous squamous cell carcinoma (laCSCC).

OBJECTIVES

To report final analysis of weight-based cemiplimab in mCSCC and laCSCC (groups 1 and 2), fixed-dose cemiplimab in mCSCC (group 3), and primary analysis of fixed-dose cemiplimab in mCSCC/laCSCC (group 6).

METHODS

Patients received cemiplimab (3 mg/kg intravenously every 2 weeks [groups 1 and 2]) or cemiplimab (350 mg intravenously [groups 3 and 6]) every 3 weeks. The primary end point was objective response rate (ORR). Duration of response (DOR) and progression-free survival (PFS) are presented per protocol, according to post-hoc sensitivity analyses that only include the period of protocol-mandated imaging assessments.

RESULTS

At 42.5 months, ORR for groups 1-3 (n = 193) was 47.2%, estimated 12-month DOR was 88.3%, and median PFS was 26.0 months. At 8.7 months, ORR for group 6 (n = 165 patients) was 44.8%; median DOR and median PFS were not reached. Serious treatment-emergent adverse event rates (grade ≥3) were groups 1-3: 31.1% and group 6: 34.5%.

LIMITATIONS

Nonrandomized study, nonsurvival primary end point.

CONCLUSION

EMPOWER-CSCC-1 provides the largest prospective data on long-term efficacy and safety for anti-programmed cell death-1 therapy in advanced CSCC.

Identification and analysis of immune cell-related genes in cutaneous squamous cell carcinoma and drug network prediction

Cutaneous squamous cell carcinoma (CSCC) is a malignant skin tumor characterized by the abnormal proliferation of keratinocytes. Immune cells have a very important role in the development of CSCC. Hence, it was vital to screen the immune cell-related biomarkers for the treatment of CSCC. Gene set variation analysis (GSVA) and immune infiltration analysis were utilised to obtain key immune cells. Weighted gene co-expression network analysis (WGCNA) was conducted to screen key module genes related to immune cell. At the same time, differential analysis was performed to find the differentially expressed genes (DEGs) between CSCC and normal samples. The candidate genes related to immune cell in CSCC patients were certificated by Venn diagram. Protein-protein interaction (PPI) network and receiver operating characteristic (ROC) curves were selected for identifying biomarkers of CSCC. We further performed immunotherapy analysis between two expression subgroups based on single gene. Following by this, the DRUGBANK database was applied to explore the interactions between biomarkers and available therapeutic agents. Finally, the expression of biomarkers was verified through real-time quantitative polymerase chain reaction (RT-qPCR). A total of 4 key immune cells (M0 macrophages, resting dendritic cells, resting mast cells, and activated mast cells) were identified. Furthermore, we obtained 982 key module genes related to immune cell. Meanwhile, 646 differentially expressed genes (DEGs) were identified. Hence, 63 candidate genes related to immune cell were selected by Venn diagram. Then, we identified six biomarkers (SLC27A2, ACOX2, PECR, CRAT, FADS1 and ELOVL5) were screened. High expression group of biomarkers showed relatively high expression of immune checkpoints. Additionally, we found 10 drugs with potential therapeutic value targeting biomarkers. Eventually, the lower expression of biomarkers in tumor group was observed, which was consistent with the result from public databases. Overall, we obtained six immune cell-related biomarkers (SLC27A2, ACOX2, PECR, CRAT, FADS1 and ELOVL5) associated with CSCC, which laid a theoretical foundation for the treatment of CSCC.

Host directed immunotherapy for chronic infections and cancer

Host-directed immunotherapy (HDI) is emerging as a transformative strategy in managing chronic diseases by leveraging the host's immune system to combat disease. This innovative approach has shown promise in a range of conditions, including cancer and parasitic infections. In oncology, HDI aims to enhance the body's natural immune response against cancer cells through mechanisms such as immune checkpoint inhibition, monoclonal antibodies, and cytokine therapies. These strategies are designed to boost the immune system's ability to recognize and destroy tumors, improving patient outcomes and offering alternatives to traditional cancer treatments. Similarly, in parasitic infections, HDI focuses on strengthening the host's immune defenses to control and eradicate those infections. For diseases like malaria, leishmaniasis, and Chagas disease, HDI strategies may involve adjuvants or immune modulators that amplify the body's ability to target and eliminate parasites. By optimizing immune responses and reducing reliance on conventional treatments, HDI holds the potential to revolutionize therapeutic approaches across various chronic diseases. This chapter highlights the flexibility and potential of HDI in advancing treatments, offering novel ways for improving patient care and disease management.

Cutaneous squamous cell carcinoma-derived exosomal MicroRNA-31 acts as an oncogene by targeting the tumor suppressor RhoBTB1

Tumor-derived exosomes that transport MicroRNAs significantly influence cutaneous squamous cell carcinoma(CSCC) progression. However, the molecular mechanisms of exosomal MicroRNA-31 regulation of CSCC are mostly undefined. To determine whether a targeting relationship exists between MicroRNA-31 (miR-31) in CSCC-derived exosomes and the tumor suppressor RhoBTB1, and the regulatory effect of the relationship on tumor cells. Immunoblotting and quantitative PCR were used to measure miR-31 and RhoBTB1 levels in various cells and exosomes. Differential ultracentrifugation was used to isolate exosomes. MTT and Transwell assays were used to assess cell proliferation, migration, and invasion. Dual luciferase reporter assays were used to assess the direct interaction between miR-31 and the tumor suppressor RhoBTB1 in cutaneous squamous cell carcinoma (CSCC)-derived exosomes. Compared with a human skin keratinocyte cell line, in CSCC cell lines RhoBTB1 was downregulated and miR-31 levels were elevated. Exosomal miR-31 from CSCC cell lines directly targeted RhoBTB1 by binding to the 3' UTR of RhoBTB1. This interaction suppressed expression of RhoBTB1 and enhanced CSCC cell proliferation, migration, and invasion. MicroRNA-31 in CSCC-derived exosomes can enhance CSCC cell proliferation, migration, and invasion by suppressing expression of RhoBTB1. This finding explains, in part, the molecular mechanism of CSCC. Investigative approaches focused on suppressing miR-31 or enhancing RhoBTB1 signaling pathways are promising avenues for developing targeted therapies for CSCC.

Perineural Invasion for Risk Stratification in Cutaneous Squamous Cell Carcinoma: A Scoping Review

BACKGROUND

Microscopic perineural invasion (mPNI) is a histopathological characteristic that can be found in cutaneous squamous cell carcinoma (cSCC). In the eighth edition of the American Joint Committee on Cancer (AJCC), mPNI defined as the involvement of nerves ≥0.1 mm and nerves deeper than the dermis is included in risk stratification of cSCC. The question remains whether other mPNI features are important for optimal cSCC staging. We aimed to summarize the evidence from published studies on the independent association between various mPNI features and the risk of recurrence, metastasis and disease-specific death in patients with cSCC.

SUMMARY

Embase, PubMed, and Web of Science were searched from January 2023 to February 2024 to identify studies that reported the prognostic impact of mPNI features in patients ≥18 years with histopathologically verified cSCC. Data on study and tumour characteristics were extracted. Nineteen studies met the inclusion criteria and evaluated one or more mPNI features in cSCC including nerve diameter, the extent of mPNI, the number of affected nerves, and depth of mPNI. Two studies provided evidence that "mPNI ≥0.1 mm" and "mPNI deeper than the dermis" are significantly and independently associated with poor prognosis after correction for other mPNI features and high-risk factors. One of these studies additionally identified "involvement of ≥3 nerves" as an independent and significant predictor of higher risk of local recurrence (HR, 2.17; 95% CI: 1.03-4.56; p = 0.04).

KEY MESSAGES

Besides "nerve diameter of ≥0.1 mm" and "depth of mPNI involvement," "involvement of multiple nerves" was found to be an independent risk factor for poor prognosis and should also be considered for appropriate risk stratification.

BACKGROUND

Microscopic perineural invasion (mPNI) is a histopathological characteristic that can be found in cutaneous squamous cell carcinoma (cSCC). In the eighth edition of the American Joint Committee on Cancer (AJCC), mPNI defined as the involvement of nerves ≥0.1 mm and nerves deeper than the dermis is included in risk stratification of cSCC. The question remains whether other mPNI features are important for optimal cSCC staging. We aimed to summarize the evidence from published studies on the independent association between various mPNI features and the risk of recurrence, metastasis and disease-specific death in patients with cSCC.

SUMMARY

Embase, PubMed, and Web of Science were searched from January 2023 to February 2024 to identify studies that reported the prognostic impact of mPNI features in patients ≥18 years with histopathologically verified cSCC. Data on study and tumour characteristics were extracted. Nineteen studies met the inclusion criteria and evaluated one or more mPNI features in cSCC including nerve diameter, the extent of mPNI, the number of affected nerves, and depth of mPNI. Two studies provided evidence that "mPNI ≥0.1 mm" and "mPNI deeper than the dermis" are significantly and independently associated with poor prognosis after correction for other mPNI features and high-risk factors. One of these studies additionally identified "involvement of ≥3 nerves" as an independent and significant predictor of higher risk of local recurrence (HR, 2.17; 95% CI: 1.03-4.56; p = 0.04).

KEY MESSAGES

Besides "nerve diameter of ≥0.1 mm" and "depth of mPNI involvement," "involvement of multiple nerves" was found to be an independent risk factor for poor prognosis and should also be considered for appropriate risk stratification.

KS-cSCC-1 and KS-cSCC-2: two novel cutaneous squamous cell carcinoma cell lines established from Japanese patients

Introduction

Cutaneous squamous cell carcinoma (cSCC) is a common form of skin cancer. Less accessibility to the cSCC cell lines has limited analyses of this disease. Thus, we here aimed to establish novel cSCC cell lines from patient's cSCC lesions.

Methods

Two novel cSCC cell lines (named KS-cSCC-1 and KS-cSCC-2) were established from an axillary lymph node metastasis of a Japanese female and an inguinal lymph node metastasis of a Japanese male. The characteristics of the established cell lines were assessed by in vitro analyses.

Results

The cells were successfully maintained for more than 9 months, with a doubling time of 47.5 ± 1.11 h (KS-cSCC-1) and 39.2 ± 5.78 h (KS-cSCC-2). The cell lines exhibited constant growth, spheroid formation, and invasiveness. Short tandem repeat analyses and immunohistochemistry confirmed that both cell lines are identical to their original tumor. The KS-cSCC-1 cells were weakly positive for CK14 and strongly positive for CK10, while the KS-cSCC-2 showed opposite expression patterns. Chemosensitivity of the cell lines was further tested and the cells were sensitive to anticancer drugs which are used to treat cSCC.

Conclusion

The KS-cSCC-1 and KS-cSCC-2 cell lines were promising resources for basic and preclinical research on cSCC to better define the tumor characteristics and treatment strategy of this cancer.

Global research trends in the treatment of squamous cell carcinoma over the past decade: A bibliometric analysis

Objective

This study aims to identify research trends and hot spots in the treatment of Squamous Cell Carcinoma (SCC) over the past decade using bibliometric analysis.

Methods

Data were extracted from the Web of Science Core Collection, including Science Citation Index Expanded (SCI-Expanded), Social Sciences Citation Index (SSCI), and Emerging Sources Citation Index (ESCI). The data underwent manual cleaning to remove inaccuracies and irrelevancies, followed by transformation into an analyzable format via the VOSviewer software. This tool facilitated the visualization of co-occurrence networks and keyword maps, highlighting the relationships and the prominence of research themes.

Results

A total of 46448 authors from 7374 institutions across 108 countries contributed to the literature, reflecting a broad international effort. The study documented a consistent increase in SCC-related publications up to 2020, with some variability in subsequent years. Notably, the United States, Germany, China, the United Kingdom, and France were predominant in this research area. The University of Texas MD Anderson Cancer Center and the University of Pittsburgh were leading contributors in terms of publication volume and citation impact. Key journals included 'Oral Oncology' and 'Clinical Cancer Research', which were central to the dissemination of high-impact research. Our keyword analysis identified three major research clusters focused on molecular mechanisms, clinical treatment strategies, and emerging interests in immunotherapeutic approaches.

Conclusions

The extensive collaboration and the increasing publication trend underscore the growing global commitment to advancing SCC treatment. The high level of engagement from top institutions and the concentration of research in influential journals reflect the field's dynamic evolution towards innovative and effective treatment modalities. This study provides a valuable overview for researchers, guiding future studies towards areas of high impact and emerging trends in SCC treatment. The findings advocate for enhanced focus on personalized medicine and combination therapies, which are poised to improve outcomes for SCC patients.

Cutaneous tissue samples show significant shrinkage during histopathological work-up: a real-world study

BACKGROUND

Excision and histological examination of cutaneous neoplasms are very common diagnostic and therapeutic procedures in dermatological practice. There are often discrepancies between tissue seize in vivo and after histopathological work-up. This may raise questions according to tumor sizes or safety margins.

METHODS

To investigate the effect of excision and histological processing on the properties of cutaneous neoplasms in real-life 401 specimens in 324 patients were prospectively investigated. Delineated excision margins of cutaneous neoplasms were documented prior to (T0) and post excision (T1). Length, width and thickness were measured after ≥48 h of formalin fixation (T2) and after sectioning (T3) on final histological slices. Accompanying parameters such as patient age, gender, anatomical site, and tumor entity were evaluated.

RESULTS

All post-processed tissue exhibited a significant (P<0.001) median (interquartile range) reduction in length, width and thickness of 21.0% (9.5-30.0), 30.7% (20.0-40.0), and 28.0% (4.8-46.7), respectively, irrespective of site, patient age or tumor entity. Maximum median (IQR) reduction for the length and the width was observed right after excision (17.0% [4.3-25.0] and 14.0% [11.1-28.6] reduction). No significant median (IQR) tissue changes between T1 and T2 were observed (length: 4.8% (-4.3-13.3); width: 0% (-17.6-11.1); thickness 0% (-32.0-20.0). Subgroup analyses showed significantly greater tissue shrinkage in younger patients and for tissue sample sites (trunk or lower extremities).

CONCLUSIONS

Most relevant shrinkage of cutaneous samples occurs right after excision. Age- and site-depended tissue contractility can influence these effects. Formalin fixation does not affect tissue shrinkage. Smaller tissue sizes on histopathological reports are to be expected.

Treatment benefit of electrochemotherapy for superficial squamous cell carcinoma: a systematic review and single-arm meta-analysis

OBJECTIVE

Treating aggressive superficial squamous cell carcinoma (SCC) poses challenges due to invasiveness. Palliative care is recommended for inoperable cases with extensive tumors near vital organs, risking disfigurement or functional impairment. Electrochemotherapy (ECT) is an emerging cutaneous tumor treatment, but its efficacy against superficial SCC remains uncertain. This study conducts a systematic review and single-arm meta-analysis to evaluate ECT's effectiveness against superficial SCC and provide current evidence for clinical practice.

METHODS

Embase, PubMed and Cochrane Library were searched for studies up to May 2023. The random effects model analyzed complete response (CR) and partial response (PR), with subgroup assessment based on drug dosage, treatment response evaluation, tumor size, primary/recurrent status, and tumor location.

RESULTS

Ten studies involving 162 patients and 208 tumors were included. Pooled CR and PR rates for ECT-treated superficial SCC were 66.5% (95% CI 48.4%-82.5%; I2 = 84%) and 20.3% (95% CI 10.5%-32.3%; I2 = 70%), respectively. Subgroup analysis indicated ECT's superiority in treating primary tumors (PR: 70%, CR: 30%) and tumors ≤ 3 cm (PR: 81.3%, CR: 10.1%) compared to recurrent tumors (PR: 56.7%, CR: 36.5%) and tumors > 3 cm (PR: 45.2%, CR: 34.4%).

CONCLUSION

This single-arm meta-analysis confirms ECT's efficacy against superficial SCC, especially in primary tumors and those ≤ 3 cm in diameter. The study highlights the impact of tumor location and response evaluation on ECT's benefits, warranting further investigation through additional research.

Dermoscopy of Squamous Cell Carcinoma: From Actinic Keratosis to Invasive Forms

When performing the dermoscopy of squamous cell carcinoma and its precursors we differentiate among keratin-related, vascular, and pigment-related criteria. Non-pigmented actinic keratoses are characterized by the "strawberry pattern". Pigmented actinic keratosis shows a significant dermatoscopic overlap with lentigo maligna, but the presence of pigmented scales, erythema, and prominent follicles favors its diagnosis. Bowen's disease is characterized by clustered glomerular vessels, white-yellowish scales, and brown or grey dots arranged in lines in its pigmented variant. Finally, dermoscopy allows us to detect invasive squamous cell carcinoma in its early stages and differentiate it from its precursors. Furthermore, its presentation may vary depending on the degree of differentiation, with keratin-associated criteria predominating in well-differentiated tumors, while the atypical vascular pattern will predominate in poorly differentiated tumors.

[Translated article] Dermoscopy of Squamous Cell Carcinoma: From Actinic Keratosis to Invasive Forms

When the dermoscopy of squamous cell carcinoma and its precursors we differentiate among keratin-related, vascular, and pigment-related criteria. Non-pigmented actinic keratoses are characterized by the "strawberry pattern". Pigmented actinic keratosis shows a significant dermatoscopic overlap with lentigo maligna, but the presence of pigmented scales, erythema, and prominent follicles favors its diagnosis. Bowen's disease is characterized by clustered glomerular vessels, white-yellowish scales, and brown or grey dots arranged in lines in its pigmented variant. Finally, dermoscopy allows us to detect invasive squamous cell carcinoma in its early stages and differentiate it from its precursors. Furthermore, its presentation may vary depending on the degree of differentiation, with keratin-associated criteria predominating in well-differentiated tumors, while an atypical vascular pattern will predominate in poorly differentiated tumors.

Distinguishing of Histopathological Staging Features of H-E Stained Human cSCC by Microscopical Multispectral Imaging

Cutaneous squamous cell carcinoma (cSCC) is the second most common malignant skin tumor. Early and precise diagnosis of tumor staging is crucial for long-term outcomes. While pathological diagnosis has traditionally served as the gold standard, the assessment of differentiation levels heavily depends on subjective judgments. Therefore, how to improve the diagnosis accuracy and objectivity of pathologists has become an urgent problem to be solved. We used multispectral imaging (MSI) to enhance tumor classification. The hematoxylin and eosin (H&E) stained cSCC slides were from Shanghai Ruijin Hospital. Scale-invariant feature transform was applied to multispectral images for image stitching, while the adaptive threshold segmentation method and random forest segmentation method were used for image segmentation, respectively. Synthetic pseudo-color images effectively highlight tissue differences. Quantitative analysis confirms significant variation in the nuclear area between normal and cSCC tissues (p < 0.001), supported by an AUC of 1 in ROC analysis. The AUC within cSCC tissues is 0.57. Further study shows higher nuclear atypia in poorly differentiated cSCC tissues compared to well-differentiated cSCC (p < 0.001), also with an AUC of 1. Lastly, well differentiated cSCC tissues show more and larger keratin pearls. These results have shown that combined MSI with imaging processing techniques will improve H&E stained human cSCC diagnosis accuracy, and it will be well utilized to distinguish histopathological staging features.

Overexpression of CCL-20 and CXCL-8 genes enhances tumor escape and resistance to cemiplimab, a programmed cell death protein-1 (PD-1) inhibitor, in patients with locally advanced and metastatic cutaneous squamous cell carcinoma

Cemiplimab has demonstrated relevant clinical activity in cutaneous squamous cell carcinoma (cSCC) but mechanisms of primary and acquired resistance to immunotherapy are still unknown. We collected clinical data from locally advanced and/or metastatic cSSC patients treated with cemiplimab in two Italian University centers. In addition, gene expression analysis by using Nanostring Technologies platform to evaluate 770 cancer- and immune-related genes on 20 tumor tissue samples (9 responders and 11 non-responders to cemiplimab) was performed. We enrolled 81 patients with a median age of 82 years. After 16.4 months of median follow-up, 12- and 24-months PFS were 53% and 42%, respectively; while 12- and 24-months OS were 71% and 61%, respectively. Treatment was well tolerated. Overall response rate (ORR) was 58%, with a disease control rate (DCR) of 77.8%. The difference between genes expressed in responder versus non-responder patient samples was substantial, particularly for genes involved in immune system regulation. Cemiplimab-resistant tumors were associated with over-expression of CCL-20 and CXCL-8. Cemiplimab confirmed efficacy and safety data in real-life cSCC patients. Overexpression of CCL-20 and CXCL-8 could represent biomarkers of lack of response to immunotherapy.

Cutaneous Squamous Cell Carcinoma: From Diagnosis to Follow-Up

Cutaneous squamous cell carcinoma (SCC) is the second most frequent skin cancer, accounting for approximately 20% of all cutaneous malignancies, and with an increasing incidence due to the progressive increment of the average age of life. The diagnosis is usually firstly suspected based on clinical manifestations; however, dermoscopic features may improve diagnostic sensitivity in cases of an uncertain diagnosis and may guide the biopsy, which should be performed to histopathologically prove the tumor. New diagnostic strategies may improve the sensitivity of the cutaneous SCC, such as reflectance confocal microscopy and line-field confocal optical coherence, for which increasing data have been recently published. Imaging has a central role in the staging of the diseases, while its exact role, as well as the choice of the best techniques, during the follow-up are not fully clarified. The aim of this literature review is to describe diagnostic clinical and instrumental tools of cutaneous SCC, with an insight into the role of imaging in the diagnosis and follow-up of cutaneous SCC.

Topically Applied Therapies for the Treatment of Skin Disease: Past, Present, and Future

The purpose of this review is to summarize essential biological, pharmaceutical, and clinical aspects in the field of topically applied medicines that may help scientists when trying to develop new topical medicines. After a brief history of topical drug delivery, a review of the structure and function of the skin and routes of drug absorption and their limitations is provided. The most prevalent diseases and current topical treatment approaches are then detailed, the organization of which reflects the key disease categories of autoimmune and inflammatory diseases, microbial infections, skin cancers, and genetic skin diseases. The complexity of topical product development through to large-scale manufacturing along with recommended risk mitigation approaches are then highlighted. As such topical treatments are applied externally, patient preferences along with the challenges they invoke are then described, and finally the future of this field of drug delivery is discussed, with an emphasis on areas that are more likely to yield significant improvements over the topical medicines in current use or would expand the range of medicines and diseases treatable by this route of administration. SIGNIFICANCE STATEMENT: This review of the key aspects of the skin and its associated diseases and current treatments along with the intricacies of topical formulation development should be helpful in making judicious decisions about the development of new or improved topical medicines. These aspects include the choices of the active ingredients, formulations, the target patient population's preferences, limitations, and the future with regard to new skin diseases and topical medicine approaches.

Establishment and molecular characterization of HCB-541, a novel and aggressive human cutaneous squamous cell carcinoma cell line

Cutaneous squamous cell carcinoma (cSCC) is a common type of skin cancer that can result in significant morbidity, although it is usually well-managed and rarely metastasizes. However, the lack of commercially available cSCC cell lines hinders our understanding of this disease. This study aims to establish and characterize a new metastatic cSCC cell line derived from a Brazilian patient. A tumor biopsy was taken from a metastatic cSCC patient, immortalized, and named HCB-541 after several passages. The cytokeratin expression profile, karyotypic alterations, mutational analysis, mRNA and protein differential expression, tumorigenic capacity in xenograft models, and drug sensitivity were analyzed. The HCB-541 cell line showed a doubling time between 20 and 30 h and high tumorigenic capacity in the xenograft mouse model. The HCB-541 cell line showed hypodiploid and hypotetraploidy populations. We found pathogenic mutations in TP53 p.(Arg248Leu), HRAS (Gln61His) and TERT promoter (C228T) and high-level microsatellite instability (MSI-H) in both tumor and cell line. We observed 37 cancer-related genes differentially expressed when compared with HACAT control cells. The HCB-541 cells exhibited high phosphorylated levels of EGFR, AXL, Tie, FGFR, and ROR2, and high sensitivity to cisplatin, carboplatin, and EGFR inhibitors. Our study successfully established HCB-541, a new cSCC cell line that could be useful as a valuable biological model for understanding the biology and therapy of metastatic skin cancer.

Previous radiotherapy increases the efficacy of cemiplimab in the treatment of locally advanced and metastatic cutaneous squamous cell carcinoma: A retrospective analysis

BACKGROUND

Cemiplimab, a programmed cell death-1 inhibitor approved in 2018 for patients with locally advanced or metastatic cutaneous squamous cell carcinoma (cSCC) who are ineligible for curative therapies, lacks clarity regarding the optimal patient selection despite its known efficacy.

OBJECTIVE

This retrospective study aims to assess the real-world treatment patterns and outcomes in patients with cSCC at our institution.

METHODS

A retrospective analysis of consecutively treated patients with cemiplimab for cSCC was conducted. Progression-free survival (PFS) and overall survival were evaluated alongside clinical-pathologic characteristics.

RESULTS

Forty-five patients were included, of which 73.3% were male with a median age of 77 years. After 18 months of median follow-up median PFS and overall survival were not reached with a mean of 21.3 months ± 2.2 months and 25.3 ± 2.1 months, respectively. Univariate and multivariate analyses revealed significant correlations only between PFS and previous radiotherapy (P values: .043 and .046, respectively).

LIMITATIONS

Limitations include its retrospective nature, the low number of patients analyzed, and the potential for inherent biases.

CONCLUSIONS

The study reveals a significant association between prior radiotherapy and improved PFS in cemiplimab-treated cSCC, suggesting the potential for combining radiotherapy with cemiplimab. Further exploration of this combined approach is warranted.

Risk factors for local and nodal recurrence in patients with head and neck cutaneous squamous cell carcinoma in a high-reference oncological center in Poland

Background

The behavior of cutaneous squamous cell carcinoma (cSCC) of the head and neck remains poorly understood. There is much controversy regarding the risk of local and nodal recurrences, as well as individual/environmental factors that increase the risk, such as tumor size, perineural invasion, and the state of the immune system. The objective was to analyze factors influencing local and/or regional lymph node recurrence in patients with cSCC in the head and neck region.

Material and methods

This retrospective single-centre study included 521 patients with cSCC of the head and neck region, with local recurrence observed in 11% and nodal recurrence in 5%. Various potential risk factors were analyzed.

Results

Statistically significant risk factors for both local and nodal recurrence include: tumor recurrence (p < 0.0001, p < 0.0001 respectively), tissue inflammation confirmed histopathologically (p < 0.0001, p = 0.0019, respectively), tumor size ≥ 10 mm (p = 0.018, p = 0.0056, respectively), invasion depth > 2 mm (p = 0.0238, p = 0.0031, respectively). Risk factors significant only for local recurrence include: surgical margins (p = 0.0056), tumor differentiation grade (p = 0.0149). No risk factors were found to be significant solely for nodal recurrence.

Conclusion

The authors argue that, in addition to classically recognized risk factors for local and nodal recurrence, attention should be paid to the presence of tissue inflammation confirmed histopathologically. It is also suggested to consider a tumor size of 10 mm as a threshold, increasing the risk of recurrence, instead of the frequently proposed 20 mm.

Cumulative incidence and risk factors for cutaneous squamous cell carcinoma metastases in organ transplant recipients: The Skin Care in Organ Transplant Patients in Europe-International Transplant Skin Cancer Collaborative metastases study, a prospective multicenter study

INTRODUCTION

Solid organ transplant recipients (SOTRs) are believed to have an increased risk of metastatic cutaneous squamous cell carcinoma (cSCC), but reliable data are lacking regarding the precise incidence and associated risk factors.

METHODS

In a prospective cohort study, including 19 specialist dermatology outpatient clinics in 15 countries, patient and tumor characteristics were collected using standardized questionnaires when SOTRs presented with a new cSCC. After a minimum of 2 years of follow-up, relevant data for all SOTRs were collected. Cumulative incidence of metastases was calculated by the Aalen-Johansen estimator. Fine and Gray models were used to assess multiple risk factors for metastases.

RESULTS

Of 514 SOTRs who presented with 623 primary cSCCs, metastases developed in 37 with a 2-year patient-based cumulative incidence of 6.2%. Risk factors for metastases included location in the head and neck area, local recurrence, size > 2 cm, clinical ulceration, poor differentiation grade, perineural invasion, and deep invasion. A high-stage tumor that is also ulcerated showed the highest risk of metastasis, with a 2-year cumulative incidence of 46.2% (31.9%-68.4%).

CONCLUSIONS

SOTRs have a high risk of cSCC metastases and well-established clinical and histologic risk factors have been confirmed. High-stage, ulcerated cSCCs have the highest risk of metastasis.

Advanced cutaneous squamous cell carcinoma: Impact of age on the safety and efficacy of cemiplimab and the prognostic significance of blood biomarkers

INTRODUCTION

Age-related differences in the safety profile of cemiplimab for patients with locally advanced or metastatic cutaneous squamous cell carcinoma (cSCC) have not been well described. We investigated the association of increasing age with immune related adverse events (irAE) from cemiplimab, efficacy outcomes, and the prognostic significance of pre-treatment blood biomarkers in contemporary practice.

MATERIALS AND METHODS

Patients starting first-line cemiplimab for locally advanced or metastatic cSCC at British Columbia Cancer between April 2019 and January 2023 were identified. Landmark four-month logistic regression analysis compared the odds of developing irAE or sequelae amongst patients aged <75 years to those aged 75-84 or ≥ 85. Objective responses were determined using Response Evaluation Criteria in Solid Tumors version 1.1. Univariable Cox proportional hazard (PH) regression modelling of factors associated with overall survival (OS) was performed.

RESULTS

Of 106 patients, the proportions aged <75, 75-84, and ≥ 85 years were 34%, 45%, and 21%, respectively. Overall, the proportion of patients with irAE ≥ grade 3, cemiplimab discontinuation, and hospitalization for immune toxicity was 27.4%, 31.1%, and 11.3%, respectively. There was no clear association between age and the odds of high grade irAE. However, increased odds of cemiplimab discontinuation was observed in patients aged 75-84 years (p = 0.05). Patients ≥85 years had increased hospitalizations due to irAE (OR = 5.00, 95% CI = 0.97-37.52) with two treatment-related deaths. Objective responses were similar across age cohorts (50.0%, 60.4%, and 54.5%) but progressive disease was higher in the age ≥ 85 group (22.2%, 18.8%, and 31.8%). On Cox PH regression analysis, age ≥ 85 years (vs. <75), Eastern Cooperative Oncology Group performance status 2-3 (vs. 0-1), and neutrophil to lymphocyte ratio (NLR) ≥7.80 (vs. <7.80) were associated with shorter survival.

DISCUSSION

While the odds of high grade irAE were similar across age groups, significant age-related differences in treatment discontinuation and hospitalization due to immune toxicity were observed. Despite a higher incidence of primary progression and shorter OS in the oldest cohort, cemiplimab yielded robust objective responses regardless of age. Higher pre-treatment NLR was associated with shorter survival and the cut-point identified requires further study.

Molecular mechanisms of human papilloma virus related skin cancers: A review

The human papillomavirus (HPV) belongs to the Papillomaviridae family of viruses which includes small, double-stranded DNA viral agents. Approximately 90% of HPV infections occur asymptomatically and resolve spontaneously. However, infection with high-risk viral strains can lead to the development of preneoplastic lesions, with an increased propensity to become cancerous. The location of these malignancies includes the oral cavity, cervix, vagina, anus, and vulva, among others. The role of HPV in carcinogenesis has already been demonstrated for the aforementioned neoplasia. However, regarding skin malignancies, the mechanisms that pinpoint the role played by HPV in their initiation and progression still elude our sight. Until now, the only fully understood mechanism of viral cutaneous oncogenesis is that of human herpes virus 8 infection in Kaposi sarcoma. In the case of HPV infection, however, most data focus on the role that beta strains exhibit in the oncogenesis of cutaneous squamous cell carcinoma (cSCC), along with ultraviolet radiation (UVR) and other environmental or genetic factors. However, recent epidemiological investigations have highlighted that HPV could also trigger the onset of other non-melanocytic, for example, basal cell carcinoma (BCC), and/or melanocytic skin cancers, for example, melanoma. Herein, we provide an overview of the role played by HPV in benign and malignant skin lesions with a particular focus on the main epidemiological, pathophysiological, and molecular aspects delineating the involvement of HPV in skin cancers.

Guidelines for the diagnosis and treatment of cutaneous squamous cell carcinoma: a GRADE approach for evidence evaluation and recommendations by the Italian Association of Medical Oncology

Cutaneous squamous cell carcinoma (CSCC) accounts for ∼20%-25% of all skin tumors. Its precise incidence is often challenging to determine due to limited statistics and its incorporation with mucosal forms. While most cases have a favorable prognosis, challenges arise in patients presenting with locally advanced or metastatic forms, mainly appearing in immunocompromised patients, solid organ transplantation recipients, or those facing social difficulties. Traditionally, chemotherapy and targeted therapy were the mainstays for advanced cases, but recent approvals of immunotherapeutic agents like cemiplimab and pembrolizumab have revolutionized treatment options. These guidelines, developed by the Italian Association of Medical Oncologists (AIOM) using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach, aim to guide clinicians in diagnosing, treating, and monitoring patients with CSCC, covering key aspects from primitive tumors to advanced stages, selected by a panel of experts selected by AIOM and other national scientific societies. The incorporation of these guidelines into clinical practice is expected to enhance patient care and address the evolving landscape of CSCC management.

Interdisciplinary management of skin cancer

The interdisciplinary treatment of skin cancer in the head and neck area requires close collaboration between different specialist disciplines. The most common non-melanoma skin cancer tumor entities are cutaneous squamous cell carcinoma and basal cell carcinoma as well as their precursor lesions. One of the less common tumors is Merkel cell carcinoma, which also occurs primarily in light-exposed areas and, in contrast to squamous and basal cell carcinoma, is more likely to metastasize. Due to the low tendency of basal cell carcinoma as well as cutaneous squamous cell carcinoma to metastasize, a cure can often be achieved by surgery. If the tumor growth exceeds certain levels it may require collaboration between dermatology and otorhinolaryngology. The primary goal of this interdisciplinary collaboration is to achieve a functional, cosmetically and aesthetically acceptable result in addition to adequate tumor treatment. Depending on the stage of the tumor and the clinical course, a case may be discussed in an interdisciplinary tumor board in order to determine a personalised, appropriate and adequate treatment concept for each patient, including prevention, therapy and follow-up.

Photodynamic Therapy for the Treatment of Bowen's Disease: A Review on Efficacy, Non-Invasive Treatment Monitoring, Tolerability, and Cosmetic Outcome

Bowen's disease represents the in situ form of cutaneous squamous cell carcinoma; although it has an excellent prognosis, 3-5% of lesions progress to invasive cutaneous squamous cell carcinoma, with a higher risk in immunocompromised patients. Treatment is therefore always necessary, and conventional photodynamic therapy is a first-line option. The aim of this review is to provide an overview of the clinical response, recurrence rates, safety, and cosmetic outcome of photodynamic therapy in the treatment of Bowen's disease, considering different protocols in terms of photosensitizers, light source, and combination treatments. Photodynamic therapy is a valuable option for tumors at sites where wound healing is poor/delayed, in the case of multiple and/or large tumors, and where surgery would be difficult or invasive. Dermoscopy and reflectance confocal microscopy can be used as valuable tools for monitoring the therapeutic response. The treatment is generally well tolerated, with mild side effects, and is associated with a good/excellent cosmetic outcome. Periodic follow-up after photodynamic therapy is essential because of the risk of recurrence and progression to cSCC. As the incidence of keratinocyte tumors increases, the therapeutic space for photodynamic therapy will further increase.

Diagnosis of invasive cutaneous squamous cell carcinoma, imaging and staging

The assessment of patients with a lesion raising the suspicion of an invasive cutaneous squamous cell carcinoma (cSCC) is a frequent clinical scenario. The management of patients with cSCC is a multistep approach, starting with the correct diagnosis. The two main diagnostic goals are to differentiate from other possible diagnoses and correctly recognize the lesion as cSCC, and then to determine the tumor spread (perform staging), that is if the patient has a common primary cSCC or a locally advanced cSCC, or a metastatic cSCC (with in-transit, regional lymph nodal, or rarely distant metastasis). The multistep diagnostic approach begins with the clinical characteristics of the primary cSCC, it is complemented with features with dermoscopy and, if available, reflectance confocal microscopy and is confirmed with histopathology. The tumor spread is assessed by physical examination and, in some cases, ultrasound and/or computed tomography or magnetic resonance imaging, mainly to investigate for regional lymph node metastasis or for local infiltration into deeper structures. In the last step, the clinical, histologic and radiologic findings are incorporated into staging systems.

Head and neck nonmelanoma skin cancers: surgical management and debated issues

PURPOSE OF REVIEW

This review critically assesses the current literature and guidelines, aiming to clarify some of the most important factors that impact surgical strategies of head and neck nonmelanoma skin cancers (NMSCs), focusing on squamous, basal, and Merkel cell carcinomas.

RECENT FINDINGS

Recent developments underscore the complexity of treatment for NMSC, particularly in the head and neck region. There is a lack of high-level evidence for the management of these tumors, especially in advanced stages. The need to tailor the extent of surgical margins and parotid/neck management to different histotypes, considering the varying risk factors for recurrence, is beginning to emerge in the literature. Moreover, the role of immunotherapy and targeted therapies for locally advanced disease, alongside traditional treatment options, is progressively growing.

SUMMARY

NMSCs represent a heterogeneous group of malignancies with varying treatment complexities and prognoses. Management of NMSC is evolving towards an increasingly personalized strategy within a multidisciplinary therapeutic framework.

Impact of COVID-19 Pandemic on Cutaneous Squamous Cell Carcinoma: A Single-Centre Study of Epidemiologic, Clinic and Histopathological Factors

BACKGROUND

The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer.

OBJECTIVE

To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic.

MATERIAL & METHODS

We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected.

RESULTS

248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases.

CONCLUSIONS

Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future.

Excision pathways for keratinocyte cancers diagnosed by teledermatology: a retrospective review

Introduction The New Zealand population has one of the highest incidences of skin cancer in the world. Hospital waiting lists for surgical excision of keratinocytic skin cancers (basal cell carcinoma and squamous cell carcinoma) are lengthy, and increasingly, excisions are undertaken in primary care. Teledermatology, in response to general practitioners' electronic referrals (e-referrals), can improve clinical communication between general practitioners and dermatologists. Aim The aim of this study was to evaluate an excision pathway for keratinocytic cancers diagnosed by teledermatology. Methods A retrospective observational descriptive review of a 3-month cohort of primary care e-referrals was undertaken. Results Three hundred and fifty eight suspected keratinocytic cancers (KCs) were diagnosed by teledermatology; histology reports confirmed KC in 201 of 267 excisions (75%). The majority (77.2%) were excised by general practitioners an average of 25 days after the dermatologist's recommendation. The rest were excised by plastic surgeons in private (3.4%) or at a public hospital (19.5%) after an average of 40 or 134 days, respectively. Discussion E-referral pathways are now widely implemented. However, the ideal workflow for skin cancer management is unknown. We have demonstrated in New Zealand that surgery can be undertaken in primary care within a month of a teledermatology diagnosis and excision recommendation. Conclusion This study reports prompt excision of KCs by general practitioners after an e-referral and a teledermatology response.

Impact of COVID-19 Pandemic on Cutaneous Squamous Cell Carcinoma: A Single-Centre Study of Epidemiologic, Clinic and Histopathological Factors

BACKGROUND

The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer.

OBJECTIVE

To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic.

MATERIAL & METHODS

We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected.

RESULTS

248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases.

CONCLUSIONS

Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future.

Extracellular Vesicles as Novel Diagnostic and Therapeutic Agents for Non-Melanoma Skin Cancer: A Systematic Review

Standard non-melanoma skin cancer (NMSC) treatment involves surgery, recently combined with chemotherapy or immunotherapy in cases of advanced tumors. EVs, including exosomes, are integral to carcinogenesis, and are found in NMSC releasing mediators impacting tumor progression. Nevertheless, the precise intercellular signaling role of NMSC-derived EVs remains unclear. This review aims to elucidate their potential role in NMSC diagnosis and treatment. This systematic review encompassed literature searches in electronic databases from inception to September 2023, based on certain inclusion and exclusion criteria, addressing NMSC-derived EVs, their molecular cargo, and their implications in the diagnosis, prognosis, and treatment of NMSC. Key components were identified. Extracellular vesicle (EV) proteins and RNA have emerged as diagnostic biomarkers in EV-based liquid biopsy. Circular RNA CYP24A1, known for its molecular stability, holds promise as a diagnostic biomarker. Long noncoding RNAs (lincRNA-PICSAR) and Desmoglein 2 (DSg2) are linked to drug resistance, serving as prognostic biomarkers. EV mediators are being actively investigated for their potential role as drug delivery agents. In conclusion, this systematic review showed that NMSC-derived EVs display promise as therapeutic targets and diagnostic biomarkers. Further research is imperative to fully comprehend EV mechanisms and explore their potential in cancer diagnosis and treatment.

Differential Immunoexpression of Inhibitory Immune Checkpoint Molecules and Clinicopathological Correlates in Keratoacanthoma, Primary Cutaneous Squamous Cell Carcinoma and Metastases

Beyond established anti-programmed cell death protein 1/programmed cell death ligand 1 immunotherapy, T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domain (TIGIT) and its ligand CD155 are promising novel inhibitory immune checkpoint targets in human malignancies. Yet, in cutaneous squamous cell carcinoma, evidence on the collective expression patterns of these inhibitory immune checkpoints is scarce. Complete tumour sections of 36 cutaneous squamous cell carcinoma, 5 cutaneous metastases and 9 keratoacanthomas, a highly-differentiated, squamoproliferative tumour, with disparately benign biologic behaviour, were evaluated by immunohistochemistry for expression of programmed cell death ligand 1 (Tumor Proportion Score, Immune Cell Score), TIGIT, CD155 and CD8+ immune infiltrates. Unlike keratoacanthomas, cutaneous squamous cell carcinoma displayed a strong positive correlation of programmed cell death ligand 1 Tumor Proportion Score and CD115 expression (p < 0.001) with significantly higher programmed cell death ligand 1 Tumor Proportion Score (p < 0.001) and CD155 expression (p < 0.01) in poorly differentiated G3-cutaneous squamous cell carcinoma compared with keratoacanthomas. TIGIT+ infiltrates were significantly increased in programmed cell death ligand 1 Immune Cell Score positive primary tumours (p = 0.05). Yet, a strong positive correlation of TIGIT expression with CD8+ infiltrates was only detected in cutaneous squamous cell carcinoma (p < 0.01), but not keratoacanthomas. Providing a comprehensive overview on the collective landscape of inhibitory immune checkpoint expression, this study reveals associations of novel inhibitory immune checkpoint with CD8+ immune infiltrates and tumour differentiation and highlights the TIGIT/CD155 axis as a potential new target for cutaneous squamous cell carcinoma immunotherapy.

Intraoperative Flow Cytometry for the Rapid Diagnosis and Validation of Surgical Clearance of Non-Melanoma Skin Cancer: A Prospective Clinical Feasibility Study

Non-melanoma skin cancer (NMSC) is the most prevalent cancer in humans, with a high global incidence. We present a prospective clinical feasibility study on the use of intraoperative flow cytometry (iFC) for the instant diagnosis of NMSC and its complete surgical clearance. Flow cytometry, a laser-based technique, quantifies cell features, which has applications in cancer research. This study aim is to explore the potential applicability of iFC in detecting and characterizing NMSC and its surgical margins. In total, 30 patients who underwent diagnosis for NMSC were recruited. The method demonstrated high sensitivity (95.2%) and specificity (87.1%), with an accuracy of 91.1%, as confirmed with a receiver operating characteristic curve analysis. The results also indicated that most tumors were diploid, with two cases being hypoploid. The average G0/G1 fractions for normal and tumor tissue samples were 96.03 ± 0.30% and 88.03 ± 1.29%, respectively, with the tumor index escalating from 3.89 ± 0.30% to 11.95 ± 1.29% in cancerous cells. These findings underscore iFC's capability for precise intraoperative NMSC characterization and margin evaluation, promising enhanced complete tumor excision rates. Given the technique's successful application in various other malignancies, its implementation in NMSC diagnosis and treatment holds significant promise and warrants further research in clinical trials.

Management of Cutaneous Squamous Cell Carcinoma of the Scalp: The Role of Imaging and Therapeutic Approaches

Cutaneous squamous cell carcinoma (cSCC) is the second most common subtype of skin cancer. The scalp is one of the most frequently affected locations and is associated with a higher rate of complications, compared to other locations. In addition, it has a characteristic thickness and anatomical structure that may influence both growth pattern and treatment of primary cSCC; while clinical peripheral margins may be easily achieved during the surgery, vertical excision of the tumor is limited by the skull. Despite having a unique anatomy, current guidelines do not contemplate specific recommendations for scalp cSCC, which leads to inconsistent decision-making in multidisciplinary committees when discussing tumors with high risk factors or with close margins. This article provides specific recommendations for the management of patients with scalp cSCC, based on current evidence, as well as those aspects in which evidence is lacking, pointing out possible future lines of research. Topics addressed include epidemiology, clinical presentation and diagnosis, imaging techniques, surgical and radiation treatments, systemic therapy for advanced cases, and follow-up. The primary focus of this review is on management of primary cSCC of the scalp with localized disease, although where relevant, some points about recurrent cSCCs or advanced disease cases are also discussed.

Atypical Site of Presentation of a Rare Type of SMARCA4-Positive Cutaneous Squamous Cell Carcinoma of the Skin: Case Report and Review of the Literature

Cutaneous squamous cell carcinoma (cSCC) comprises 20% of cases of nonmelanoma skin cancers in the United States. In total, 3% to 5% of squamous cell carcinoma (SCC) are metastatic at the time of presentation, associated with significant mortality due to a lack of standardized treatment options. In total, 95% of these tumors are amenable to the initial standard of treatment, which is surgical resection. However, a small percentage of them require systemic therapy as they are either locally advanced to regional lymph nodes or have distant metastasis. The common sites of presentation of cSCC are the scalp and the face with predictable spread to the intra-parotid, upper jugular, and perifacial lymph nodes. In our case report, however, our patient had a large lump lesion on the upper back, an unusual site of presentation of cSCC, with locally advanced metastasis to the left axillary lymph nodes. Subsequently, the tumor marker study revealed a positive SMARCA4 variant (the essential ATPase subunit of the Switch (SWI)/Sucrose Nonfermenting (SNF) chromatin-remodeling complex) that is even rarer in the context of cSCC. Furthermore, abnormalities in SWI/SNF chromatin-remodeling complex subunits have shown promising results as a target therapy for immune checkpoint inhibitor (ICI) therapy. We present an atypical presentation site of locally advanced rare variant SMARCA4-positive cSCC in a patient who received treatment with chemoradiation and systemic therapy with ICI after primary surgical resection. To date, only 2 cases of SMARCA4-positive cSCC were found in the literature with no details of the treatment received. Our case is unique in its atypical site of presentation as well as showing partial response to radiotherapy (RT) and systemic therapy with ICI.

Epidermal growth factor receptor inhibitors in advanced cutaneous squamous cell carcinoma: A systematic review and meta-analysis

Patients with advanced cutaneous squamous cell carcinoma (cSCC) who are not eligible for or who fail to respond to anti-PD1 immunotherapy have few treatment options. Epidermal growth factor receptor (EGFR) inhibitors have been investigated as a therapeutic option for advanced cSCC; however, data are limited to small single-arm trials or retrospective studies. A systematic review and meta-analysis was conducted to PRISMA guidelines (CRD42023394300). Studies reporting on outcomes of EGFR inhibition in advanced cSCC were identified. Objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and adverse event (AE) rate were pooled using a random effects model and the inverse variance method. Twelve studies (six prospective, six retrospective) were identified, representing 324 patients. Pooled ORR was 26% (95% confidence interval [CI] 18-36), median PFS was 4.8 months (95% CI 3.9-6.6) and median OS was 11.7 months (95% CI 9.2-14.1). Any grade AEs occurred in 93% of patients (95% CI 85-97) while grade 3 and higher AEs occurred in 30% (95% CI 14-54). These results were similar between anti-EGFR monoclonal antibodies (MAbs) and tyrosine kinase inhibitors (TKIs). EGFR inhibitors can be considered in patients with advanced cSCC who are contraindicated for or progress on first-line anti-PD1 immunotherapy. Future studies should evaluate their activity and safety following anti-PD1, identify predictive biomarkers for their efficacy and explore combination approaches.

Single-cell sequencing highlights heterogeneity and malignant progression in actinic keratosis and cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most frequent of the keratinocyte-derived malignancies with actinic keratosis (AK) as a precancerous lesion. To comprehensively delineate the underlying mechanisms for the whole progression from normal skin to AK to invasive cSCC, we performed single-cell RNA sequencing (scRNA-seq) to acquire the transcriptomes of 138,982 cells from 13 samples of six patients including AK, squamous cell carcinoma in situ (SCCIS), cSCC, and their matched normal tissues, covering comprehensive clinical courses of cSCC. We identified diverse cell types, including important subtypes with different gene expression profiles and functions in major keratinocytes. In SCCIS, we discovered the malignant subtypes of basal cells with differential proliferative and migration potential. Differentially expressed genes (DEGs) analysis screened out multiple key driver genes including transcription factors along AK to cSCC progression. Immunohistochemistry (IHC)/immunofluorescence (IF) experiments and single-cell ATAC sequencing (scATAC-seq) data verified the expression changes of these genes. The functional experiments confirmed the important roles of these genes in regulating cell proliferation, apoptosis, migration, and invasion in cSCC tumor. Furthermore, we comprehensively described the tumor microenvironment (TME) landscape and potential keratinocyte-TME crosstalk in cSCC providing theoretical basis for immunotherapy. Together, our findings provide a valuable resource for deciphering the progression from AK to cSCC and identifying potential targets for anticancer treatment of cSCC.

European consensus-based interdisciplinary guideline for invasive cutaneous squamous cell carcinoma. Part 1: Diagnostics and prevention-Update 2023

Invasive cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in white populations, accounting for 20% of all cutaneous malignancies. Overall, cSCC mostly has very good prognosis after treatment, with 5-year cure rates greater than 90%. Despite the overall favourable prognosis and the proportionally rare deaths, cSCC is associated with a high total number of deaths due to its high incidence. A collaboration of multidisciplinary experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF), the European Society for Radiotherapy and Oncology (ESTRO), the European Union of Medical Specialists (UEMS), the European Academy of Dermatology and Venereology (EADV) and the European Organization of Research and Treatment of Cancer (EORTC), was formed to update recommendations on cSCC, based on current literature and expert consensus. Part 1 of the guidelines addresses the updates on classification, epidemiology, diagnosis, risk stratification, staging and prevention in immunocompetent as well as immunosuppressed patients.

The clinical relevance of OSM in inflammatory diseases: a comprehensive review

Oncostatin M (OSM) is a pleiotropic cytokine involved in a variety of inflammatory responses such as wound healing, liver regeneration, and bone remodeling. As a member of the interleukin-6 (IL-6) family of cytokines, OSM binds the shared receptor gp130, recruits either OSMRβ or LIFRβ, and activates a variety of signaling pathways including the JAK/STAT, MAPK, JNK, and PI3K/AKT pathways. Since its discovery in 1986, OSM has been identified as a significant contributor to a multitude of inflammatory diseases, including arthritis, inflammatory bowel disease, lung and skin disease, cardiovascular disease, and most recently, COVID-19. Additionally, OSM has also been extensively studied in the context of several cancer types including breast, cervical, ovarian, testicular, colon and gastrointestinal, brain,lung, skin, as well as other cancers. While OSM has been recognized as a significant contributor for each of these diseases, and studies have shown OSM inhibition is effective at treating or reducing symptoms, very few therapeutics have succeeded into clinical trials, and none have yet been approved by the FDA for treatment. In this review, we outline the role OSM plays in a variety of inflammatory diseases, including cancer, and outline the previous and current strategies for developing an inhibitor for OSM signaling.

Real-World Experience with Cemiplimab Treatment for Advanced Cutaneous Squamous Cell Carcinoma-A Retrospective Single-Center Study

BACKGROUND

The systemic treatment of advanced cutaneous squamous cell carcinoma (cSCC) has seen significant developments in recent years. The anti-PD1 inhibitor cemiplimab has demonstrated efficacy in clinical trials, but real-world data are still limited. Here, we aimed to evaluate the efficacy and the safety of cemiplimab in a real-world clinical setting.

METHODS

A retrospective analysis was carried out for all patients who received at least two doses of cemiplimab at our department between February 2020 and January 2023. Progression-free survival (PFS), overall survival (OS), the objective response rate (ORR), the disease control rate (DCR) and adverse events (AEs) were evaluated.

RESULTS

Twenty-five patients were included with a median age of 78 (65-82) years. The median treatment duration was 48 (16-72) weeks. Five (20%) patients were immunocompromised. Sixteen patients (64%) developed AEs, including 36% serious AEs (SAEs) of grade ≥ 3. Six patients (24%) were withdrawn from treatment due to the occurrence of AEs. Among the 25 patients, 52% showed an objective response (3 complete and 10 partial responses), 76% had controlled disease and 24% experienced progression. Among the five immunocompromised patients, the ORR was 60%, while the DCR was 80%.

CONCLUSIONS

This retrospective real-world study revealed that locally advanced or metastatic cSCC could be effectively treated with cemiplimab even in elderly, polymorbid and immunocompromised patients.

Cutaneous squamous cell carcinoma of the lip successfully treated with rhenium-188 brachytherapy

Cutaneous squamous cell carcinoma (SCC) is the second most common form of skin cancer. In most cases, non-invasive SCC has a good prognosis and is curable by surgical resection. Nevertheless, a small percentage of patients pose specific management problems due to the technical difficulty of maintaining function and aesthetics because of the size or location of the tumor. An emerging therapeutic approach with high-dose brachytherapy using a nonsealed rhenium-188 resin, commercially known as Rhenium-Skin Cancer Therapy®, has been shown to be highly effective in non-invasive carcinoma, up to a thickness of 2-3 mm.

Nivolumab for locally advanced and metastatic cutaneous squamous cell carcinoma (NIVOSQUACS study)-Phase II data covering impact of concomitant haematological malignancies

BACKGROUND

Monoclonal antibodies, such as cemiplimab and pembrolizumab, against the programmed death receptor (PD)-1 have become the current standard of care and first-line treatment of advanced cutaneous squamous cell carcinoma (cSCC), proving remarkable clinical benefit and acceptable safety.

OBJECTIVES

To assess efficacy and safety of the anti-PD-1 antibody nivolumab in patients with locally advanced and metastatic cSCC.

METHODS

Patients received open-label nivolumab 240 mg intravenously every 2 weeks for up to 24 months. Patients with concomitant haematological malignancies (CHMs), either non-progressing or stable under active therapy, were eligible for inclusion.

RESULTS

Of 31 patients with a median age of 80 years, 22.6% of patients achieved an investigator assessed complete response, resulting in an objective response rate (ORR) of 61.3% and a disease control rate (DCR) of 64.5%. Progression-free survival (PFS) was 11.1 months, and the median overall survival (OS) was not reached after 24 weeks of therapy. Median follow-up was 23.82 months. Subgroup analysis of the CHM cohort (n = 11; 35%) revealed an ORR of 45.5%, a DCR of 54.5%, a median PFS of 10.9 months, and median OS of 20.7 months. Treatment related adverse events were reported in 58.1% of all patients (19.4% grade 3, the remaining grade 1 or 2). PD-L1 expression and CD-8+ T-cell infiltration did not significantly correlate with clinical response, although a trend towards a shorter PFS of 5.6 months was observed with PD-L1 negativity and low CD8+ intratumoral infiltration.

CONCLUSION

This study demonstrated robust clinical efficacy of nivolumab in patients with locally advanced and metastatic cSCCs and a tolerability comparable to data of other anti-PD-1 antibodies. Favourable outcomes were obtained despite involving the oldest hitherto reported study cohort for anti-PD-1 antibodies and a significant proportion of CHM patients prone to high risk tumours and an aggressive course otherwise typically excluded from clinical trials.

Personalised decision making to predict absolute metastatic risk in cutaneous squamous cell carcinoma: development and validation of a clinico-pathological model

Background

Cutaneous squamous cell carcinoma (cSCC) is a common skin cancer, affecting more than 2 million people worldwide yearly and metastasising in 2-5% of patients. However, current clinical staging systems do not provide estimates of absolute metastatic risk, hence missing the opportunity for more personalised treatment advice. We aimed to develop a clinico-pathological model that predicts the probability of metastasis in patients with cSCC.

Methods

Nationwide cohorts from (1) all patients with a first primary cSCC in The Netherlands in 2007-2008 and (2) all patients with a cSCC in 2013-2015 in England were used to derive nested case-control cohorts. Pathology records of primary cSCCs that originated a loco-regional or distant metastasis were identified, and these cSCCs were matched to primary cSCCs of controls without metastasis (1:1 ratio). The model was developed on the Dutch cohort (n = 390) using a weighted Cox regression model with backward selection and validated on the English cohort (n = 696). Model performance was assessed using weighted versions of the C-index, calibration metrics, and decision curve analysis; and compared to the Brigham and Women's Hospital (BWH) and the American Joint Committee on Cancer (AJCC) staging systems. Members of the multidisciplinary Skin Cancer Outcomes (SCOUT) consortium were surveyed to interpret metastatic risk cutoffs in a clinical context.

Findings

Eight out of eleven clinico-pathological variables were selected. The model showed good discriminative ability, with an optimism-corrected C-index of 0.80 (95% Confidence interval (CI) 0.75-0.85) in the development cohort and a C-index of 0.84 (95% CI 0.81-0.87) in the validation cohort. Model predictions were well-calibrated: the calibration slope was 0.96 (95% CI 0.76-1.16) in the validation cohort. Decision curve analysis showed improved net benefit compared to current staging systems, particularly for thresholds relevant for decisions on follow-up and adjuvant treatment. The model is available as an online web-based calculator (https://emc-dermatology.shinyapps.io/cscc-abs-met-risk/).

Interpretation

This validated model assigns personalised metastatic risk predictions to patients with cSCC, using routinely reported histological and patient-specific risk factors. The model can empower clinicians and healthcare systems in identifying patients with high-risk cSCC and offering personalised care/treatment and follow-up. Use of the model for clinical decision-making in different patient populations must be further investigated.

Funding

PPP Allowance made available by Health-Holland, Top Sector Life Sciences & Health, to stimulate public-private partnerships.

Recommendations for risk stratification of periocular squamous cell carcinoma

Periocular squamous cell carcinoma is a common cutaneous malignancy with generally favorable outcomes; however, the periocular region is intrinsically a high-risk location, and there exist a subset of lesions with a propensity for poor outcomes. Orbital invasion, intracranial perineural spread, nodal and distant metastasis are feared complications. There are several staging systems for eyelid carcinoma and cutaneous squamous cell carcinoma, but the definition of high-risk lesions remains heterogeneous. It is unclear exactly which lesions can be safely deescalated, and which require nodal evaluation and adjuvant multimodal therapy. We seek to answer these questions by summarizing the literature on clinicopathologic variables, molecular markers, and gene profiling tests in periocular squamous cell carcinoma, with the extrapolation of data from the cutaneous squamous cell carcinoma literature. Standardized pathology reports with information on tumor dimensions, histological subtype and grade, perineural invasion, and lymphovascular invasion should become uniform. Integration with gene expression profiling assessments will individualize and improve the predictive accuracy of risk stratification tools to ultimately inform multidisciplinary decision-making.