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

Skin cancer risk in more than 200 000 patients with haematological malignancies over 30 years: a nationwide population-based study in the Netherlands

BACKGROUND

Patients with haematological malignancies are at increased risk of developing skin cancer and often experience worse skin cancer-related outcomes. However, there is a lack of nationwide, population-based data with long-term follow-up on the incidence and risks of different skin cancer types across all haematological malignancies.

OBJECTIVES

To assess population-based risk estimates for cutaneous squamous cell carcinoma (cSCC), malignant melanoma (MM), Merkel cell carcinoma (MCC) and basal cell carcinoma (BCC) among patients with haematological malignancies, stratified by skin cancer type and haematological malignancy subgroup. These estimates can serve as a base for surveillance guidelines and patient education.

METHODS

This nationwide population-based epidemiological cohort study used data from 210 794 patients diagnosed with a haematological malignancy between 1989 and 2020 from the Netherlands Cancer Registry (NCR). In addition, data on each type of histopathologically confirmed skin cancer per patient after haematological malignancy diagnosis were retrieved from the NCR. Patients with a history of skin cancer prior to their haematological malignancy were excluded. Cumulative incidences, standardized incidence ratios (SIRs) and absolute excess risks for each of the four skin cancers were calculated and stratified by haematological malignancy subgroup, age, sex, follow-up and primary treatment.

RESULTS

The overall 10-year cumulative incidence of developing a first skin cancer was 2.6% for cSCC, 0.5% for MM, 0.05% for MCC and 4.8% for BCC. Compared with the general population, nearly all haematological malignancy subgroups showed more than a twofold increased risk of cSCC, MM, MCC and BCC. Patients with chronic lymphocytic leukaemia (CLL) showed the highest risks for each of the four skin cancers, with SIRs of 4.4 for cSCC, 2.7 for MM, 9.3 for MCC, and 2.6 for BCC. These elevated risks persisted for > 30 years after haematological malignancy diagnosis.

CONCLUSIONS

Patients with all types of haematological malignancies, and especially those with CLL, have a lifetime increased risk of developing different types of skin cancer. These findings highlight the importance of creating awareness among patients and care providers about this increased risk and promoting sun-protective measures and regular skin self-examinations in this high-risk population.

Enhancing Diagnosis in Squamous Cell Carcinoma: Non-Invasive Imaging and Multimodal Approach

Background/Objectives: Cutaneous squamous cell carcinoma (cSCC) is the second most common skin cancer, with diverse clinical presentations. This study aims to correlate findings from dermoscopy, ultrasonography, ex vivo confocal microscopy, and histology to improve diagnostic accuracy and guide better clinical management of cSCC. Methods: This cross-sectional study, conducted between July 2022 and December 2024, included 26 patients with 35 clinically suspicious cSCC tumors, analyzed through clinical, dermoscopic, high-frequency ultrasound (HFUS), ex vivo confocal fluorescence microscopy (FCM), and histopathology. Tumors were evaluated for various clinical, imaging, and histopathological criteria, such as tumor thickness, vascularization, differentiation degree, and invasion level, with FCM applied to 24 tumors for advanced microscopic analysis. Results: The study analyzed 35 cases of histopathologically confirmed cSCC, finding that invasive SCC was associated with greater tumor thickness, increased vascularization, and ulceration on both ultrasound and dermatoscopy, while in situ SCC showed homogeneous echogenicity and specific dermoscopic patterns like dotted vessels and white halos. Strong correlations were identified between ultrasound and histopathological measurements of tumor thickness and invasion depth, and confocal microscopy revealed that features like plump bright cells and nest-like structures were linked to invasive and poorly differentiated tumors. Conclusions: This study uniquely integrates advanced imaging techniques-dermatoscopy, skin ultrasound, and ex vivo confocal microscopy-with histopathological analysis to provide new insights into tumor grade, vascularity, and invasion depth in cSCC, enhancing non-invasive diagnosis.

The Role of HPV in the Development of Cutaneous Squamous Cell Carcinoma-Friend or Foe?

The incidence of cutaneous squamous cell carcinoma (cSCC) is increasing, with UV radiation being the main cause. Other risk factors are age, sex, skin type and immunosuppression. Human papillomaviruses (HPVs) are associated with benign and malignant skin tumours. In contrast to anogenital and oropharyngeal carcinomas, which are caused by alpha papillomaviruses, the HPV types associated with cSCC belong to the beta-HPV genus. These viruses infect the skin epithelium and are widespread in skin samples from healthy people. It is assumed that HPV amplifies the DNA damage caused by UV radiation and disrupts the repair mechanisms of the cells, without remaining permanently detectable in the tumour tissue, the so-called hit-and-run theory. The HPV status of tumours appears to have a positive influence on prognosis and response to therapy due to increased immune infiltration, in particular by tissue-resident memory T cells and activation of immune effector cells. This favours responses to immunotherapies such as PD-1/PD-L1 inhibitors, whereas immunosuppression may promote a pro-carcinogenic effect. In conclusion, the role of beta HPV in the development of cSCC appears to be closely associated with the immune status of the host. Depending on the immune status, beta HPV can play either a protective or a tumour-promoting role, and in view of the increasing incidence of skin cancer worldwide, enhancing the immune response against virus-infected keratinocytes, e.g., through HPV vaccination, could represent a promising approach for the prevention and therapy of squamous cell carcinomas.

Management of Cutaneous Squamous Cell Carcinoma of the Scalp in Kidney Transplant Recipients

BACKGROUND

Organ transplant recipients are at a significantly higher risk of developing skin cancer compared to the general population, particularly cutaneous squamous cell carcinoma. Approximately 3-8% of these carcinomas are located on the scalp. Scalp reconstruction is particularly challenging, especially for large excisions, due to the thickness of the scalp, the inelastic aponeurosis of the galea, and the integrity of the hair-bearing scalp. Additionally, in organ transplant recipients, the presence of numerous comorbidities and the increased risk of infection due to immunosuppressive therapy make management more complex. Based on our experience and the existing literature, we aim to describe possible reconstruction methods and discuss the combined management of medical and immunosuppressive therapy.

METHOD

We present our experience with seven kidney transplant patients who underwent excision of cutaneous squamous cell carcinoma with a diameter larger than 3 cm. The crane technique involves three key steps. First, the tumor is excised with wide margins of disease-free tissue. Next, a pericranial flap is rotated and positioned to cover the exposed cranial bone. Finally, a bilayer dermal substitute is applied to create a microenvironment that supports skin graft implantation.

RESULTS

The crane technique was used for six patients. In one case, an O-Z rotation flap was used. All patients modified their immunosuppressive therapy, with those receiving antiproliferative therapy switching everolimus after surgery.

CONCLUSIONS

When combined with a post-operative modification of the immunosuppressive regimen, the crane technique could be considered a feasible, safe, and effective approach to managing large cSCC of the scalp in fragile patients.

The genomic landscape of cutaneous squamous cell carcinoma in Japan

Comprehensive studies of the genetic profiles of cutaneous squamous cell carcinoma (cSCC) in Japanese patients have been lacking, although an understanding of these profiles is crucial for improving treatment outcomes. Since 2019, comprehensive genomic profiling (CGP) has been covered by Japan's health insurance, and the resulting data have been compiled into a comprehensive database by the country's Center for Cancer Genomics and Advanced Therapeutics (C-CAT). In this retrospective study, we used CGP data from the C-CAT database to analyze genomic characteristics of cSCC in Japanese patients. The patients' clinical and genomic data, including the chemotherapy regimens, tumor mutational burden (TMB), and survival status, were obtained. We analyzed the cases of 152 patients, with only those evaluated by the FoundationOne® CDx included for accuracy. Among the 152 patients, the most common gene oncogenic alterations were observed in TP53 (67%), CDKN2A (54%), TERT (49%), CDKN2B (33%), and NOTCH1 (18%). TMB-high (≥10 mut/Mb) was observed in 27% (n = 41) of the patients, with a median age of 75 years for this group. TMB-low (<10 mut/Mb) was observed in 73% (n = 111) of the patients; their median age was 67 years.

From basic to clinical and therapeutic insights: news on actinic keratosis and skin squamous cell carcinoma

PURPOSE OF REVIEW

Squamous cell carcinoma (SCC) is the second most common skin cancer, with an increasing incidence. This review highlights this past year's advances regarding the understanding of its pathogenesis, newly introduced diagnostic methods and updates in prevention and treatment.

RECENT FINDINGS

While the pathogenesis of SCC progression remains unclear, new sequencing techniques are helping to better characterize these tumours at the molecular level. Recently introduced noninvasive imaging techniques are rapidly transforming SCC diagnosis and follow-up. Although nicotinamide has not demonstrated significant benefit in reducing SCC incidence among transplant recipients, larger studies are needed to achieve statistical power. Tirbanibulin, a new field treatment for actinic keratosis is now available and well tolerated for use in areas up to 100 cm 2 . Surgery remains the cornerstone of SCC treatment and can now be complemented with cemiplimab, when advanced.

SUMMARY

Recent years have seen a diagnostic revolution in dermatology, driven by noninvasive imaging and artificial intelligence; however, the physiopathogenesis of SCC progression remains poorly understood. In treatment, immune checkpoint inhibitors have shown good survival outcomes for advanced SCC. Research continues in the neoadjuvant setting and among transplanted patients, with encouraging preliminary results.

The evolving treatment landscape for CSCC

The treatment landscape for cutaneous squamous cell carcinoma (CSCC) is evolving, with immunotherapy transforming care across all stages of disease and expanding the role of dermatologists. While surgery and radiotherapy remain cornerstones for localized CSCC, immune checkpoint inhibitors (ICIs) offer durable responses and survival benefits in advanced cases. Emerging approaches, including neoadjuvant, adjuvant, and intralesional ICIs, provide dermatologists with opportunities to integrate these therapies into practice, potentially enhancing surgical outcomes and preserving function in high-risk, resectable CSCC. Preliminary data on anti-PD-1 therapy as a preventive strategy for actinic neoplasia syndrome introduces new avenues for long-term management, though further evidence is needed. As systemic immunotherapy becomes increasingly relevant in dermatology, addressing immunotherapy-related adverse events requires interdisciplinary collaboration and specialized training. These advancements emphasize the expanding responsibilities of dermatologists in CSCC management while highlighting the importance of continued research and thoughtful application of these therapies.

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.

Clinical and histopathological features of advanced cutaneous squamous cell carcinoma with varying responses to cemiplimab

BACKGROUND

Most patients with unresectable locally advanced cutaneous squamous cell carcinoma (cSCC) benefit from cemiplimab, but some do not respond. Our study aims to identify clinical and histopathological features predicting response to cemiplimab.

PATIENTS AND METHODS

We analyzed 15 patients treated with cemiplimab, assessing clinical, demographic, histopathological, and immunohistochemical characteristics and correlating them with treatment response. Furthermore, effectiveness and safety were evaluated in our cohort.

RESULTS

Our cohort included 12 males and 3 females, with a mean age of 78.1 years. The majority of tumors, accounting for 66.7%, were located in the head and neck region. Treatment was well-tolerated, with only one grade 3 colitis. There was no correlation between immune-related adverse events and treatment response. Non-responders were younger (69.4 vs. 82.5 years). A history of hematological malignancy correlated with poorer response. High mitotic rate, poor tumor differentiation, high vimentin and p53, and low E-cadherin expression were associated with worse response. Conversely, higher intratumoral inflammatory infiltrate density, presence of necrotic areas, and lower mismatch repair-protein staining correlated with better response.

CONCLUSIONS

Cemiplimab is a safe and effective therapy, particularly in elderly patients. Well-differentiated tumors with low proliferative index, intratumoral inflammatory infiltrate, and tumor necrosis may predict better clinical response.

Age over 90 years is an unfavorable prognostic factor for resectable cutaneous squamous cell carcinoma

The rapid aging of the population has led to an increase in the number of cutaneous squamous cell carcinoma (cSCC) cases among the older population. However, the characteristics of these cases remain unclear. In this study, we aimed to identify the problem by analyzing the clinical characteristics of patients with cSCC aged 90 years and over. In this retrospective study, we analyzed the characteristics of patients aged >90 years with regard to gender, risk factors for cSCC, and disease course, using data from 316 patients with cSCC who underwent surgery at the Kagoshima Medical Centre between October 2014 and September 2022. Patients were separated into two groups based on age: those aged ≥90 years (104 patients) and those aged <90 years (212 patients). Regarding the National Comprehensive Cancer Network risk classification, there was no difference between groups. Univariate, multivariate, and Cox analyses of relapse-free survival of patients in both groups indicated that the recurrence risk was significantly high among those aged ≥90 years. Patients aged ≥90 years were at higher risk for recurrence, suggesting a need for closer follow-up than that for patients aged <90 years.

Recommendations for the management of cutaneous squamous cell carcinoma: a systematic multidisciplinary Delphi consensus approach

BACKGROUND

There are gaps and unanswered questions in clinical guidelines regarding several aspects of the management of patients with cutaneous squamous cell carcinoma (cSCC).

METHODS

A scientific committee of ten cSCC specialists in Spain (dermatology, medical oncology, oral and maxillofacial surgery, plastic surgery, and radiotherapy) used ADAPTE methodology to develop recommendations by: (i) identifying clinical questions not fully answered by clinical practice guidelines; (ii) systematically reviewing the literature (published between November 2017 and July 2023 in PubMed and the Cochrane database) and grading the evidence (using Oxford levels); (iii) developing recommendations and assessing those with no consensus among the scientific committee or with evidence level 3-5 or strength of recommendation under C or D in a two-round Delphi method; and (iv) developing the final recommendations in the form of answers to key clinical questions, grading the strength of recommendation. An external group of 32 experts plus the members of the committee participated in both Delphi rounds, evaluating the appropriateness and need of the recommendations.

RESULTS

Initially, 33 recommendations were made for 26 questions; 19 recommendations were evaluated with the Delphi method. All 19 recommendations were deemed appropriate and necessary. A total of 27 final recommendations were made, concerning initial patient management, treatment of the primary tumour, management of advanced disease, specific populations, supportive and palliative care, and follow-up.

CONCLUSION

We developed 27 recommendations that answer clinical questions on the management of patients with cSCC, providing guidance on aspects that are unclear in clinical guidelines or on which guidelines differ.

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.

The Role of Gene Expression Profiling in the Management of Cutaneous Squamous Cell Cancer: A Review

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer, with an increasing global incidence. While most cases are successfully treated with surgical excision, a subset can metastasize, leading to significant morbidity and mortality. Current staging systems based on clinical and histopathological features have shown limitations in accurately predicting metastatic risk. This review examines the role of gene expression profiling (GEP), particularly the 40-gene expression profile (40-GEP) test, in improving risk stratification and management of cSCC. We assess the prognostic value of the 40-GEP test, its integration with current staging systems, and its impact on clinical decision-making. Recent studies suggest that incorporating GEP results with traditional staging methods can enhance the identification of high-risk patients, potentially leading to more personalized treatment strategies. The review also explores the challenges of implementing GEP in routine clinical practice, including cost-effectiveness considerations and the need for standardization. Finally, we discuss the implications for future cSCC management and highlight areas for further research. As molecular profiling techniques continue to evolve, GEP represents a promising approach to optimizing care for cSCC patients, aligning with the growing emphasis on personalized medicine in oncology.

Efficacy and tolerability of tirbanibulin 1% ointment in the treatment of cancerization field: a real-life Italian multicenter observational study of 250 patients

BACKGROUND

Tirbanibulin 1% ointment is approved for the field treatment of Olsen grade I actinic keratoses (AKs) of the face and scalp.

METHODS

We performed a multicenter retrospective study involving 15 dermatologic units in Italy to investigate the efficacy and tolerability of tirbanibulin in a real-life setting. 250 patients were enrolled. Tirbanibulin, 1% ointment, was applied daily for five consecutive days. The efficacy of treatment was measured with modifications of the Actinic Keratosis Area and Severity Index (AKASI). A satisfactory response was defined by complete (100% reduction in the number of lesions) or partial clearance (75-99%) of treated AKs.

RESULTS

Overall, the AKASI score was significantly reduced in the studied population (mean, from 4.1 ± 2.7 to 1.4 ± 1.5; P < 0.001). A satisfactory response was observed in 222 (88.8%) cases. The proportion of satisfactory responses was higher when follow-up was performed after 8 weeks (34/35, 97.1%). The reduction in AKASI was significant in patients with Olsen grade II or III lesions (from 5.3 ± 2.8 to 1.6 ± 1.6; P < 0.001). A satisfactory response was observed in 91/104 (87.5%) cases. AKASI reduction was also significant in patients with trunk or limb AKs (from 7.0 ± 1.3 to 2.0 ± 1.6; P = 0.018) since a satisfactory response was observed in 7/8 (87.5%) cases. Tirbanibulin was well tolerated; all adverse events (AEs) included transient local reactions at the site of treatment. Overall, 231 patients had at least one AE. Only 7 (2.8%) grade 4 AEs were recorded.

CONCLUSION

Our retrospective study confirmed that tirbanibulin 1% ointment is effective and well tolerated in a real-life setting and is also promising for Olsen grade II and grade III AKs and AKs localized on difficult-to-treat areas.

Ex Vivo Confocal Microscopy Speeds up Surgical Margin Control of Re-Excised Skin Tumors and Greatly Shortens In-Hospital Stay

BACKGROUND/OBJECTIVES

To ensure that non-melanoma skin cancer (NMSC) is completely removed in healthy tissue, micrographically controlled surgery (3D histology) is often performed, which can prolong the inpatient stay. This study examined ex vivo reflectance confocal microscopy (evRCM) for perioperative assessment of surgical margins, specifically in cases where re-excision was necessary due to incomplete removal of cutaneous tumor tissue.

METHODS

NMSC re-excisions were evaluated using evRCM by a cutaneous surgeon, with retrospective review by an independent pathologist when results differed from histology.

RESULTS

evRCM demonstrated high specificity (0.96; 95% CI, 0.90-0.99) but low sensitivity (0.20; 95% CI, 0.06-0.51). Unlike pathology, which discards outer surgical margins, evRCM examined the true surgical margins. Retrospective pathology analysis of the misdiagnosed cases confirmed that 25% (n = 2/8) were false negative and 75% (n = 6/8) were potentially false positive, resulting in a sensitivity of 0.2-0.8. Notably, evRCM led to a 113-day reduction in in-hospital stays, probably resulting in increased patient satisfaction and cost-effectiveness.

CONCLUSIONS

evRCM was valuable for speeding up the assessment of surgical margins in patients with re-excised NMSC. Proper tissue preparation and assessment require interdisciplinary collaboration between cutaneous surgeons, pathologists, and physician assistants, emphasizing the need for standardized operating procedures.

Patient-initiated follow-up for high-risk cutaneous squamous cell carcinoma: how we do it and 2 years of outcome data

BACKGROUND

For patients with high-risk cutaneous squamous cell carcinomas (cSCCs), current guidance suggests we should offer post-treatment follow-up appointments at regular intervals for 24 months. Is this to improve prognosis, provide psychological support or find the next cancer? Recent data confirm that recurrence and metastasis are rarer events, and that perhaps these intense follow-up schedules do not really lead to improved health outcomes.

OBJECTIVES

To question whether current follow-up practices are truly needed by introducing an option of patient-initiated follow-up (PIFU).

METHODS

We enrolled 476 patients with cSCC (January 2020-January 2023) who fulfilled the definition of high-risk cSCC based on guidelines in use at the time. Of the total, 59 did not fulful the inclusion criteria and were excluded; 250 (52.5%) did not recontact us during the 2-year period, with no clinical record of complications or recurrences; and 167 (35.1%) utilized the PIFU pathway, of which 119 patients required only one face-to-face appointment. Seven patients (1.5%) developed metastatic disease, 11 (2.3%) developed recurrence and 68 (14.3%) developed cSCC at another site. All lesions were identified by the patient via PIFU. We saved 1250 follow-up appointments from those who did not contact us (n = 250), financially equating to £181 462.50.

CONCLUSIONS

Our data imply that PIFU can be considered safe alternative practice for patients with cSCC. Patients independently identified the need for review without scheduled follow-up, making these appointments available to other patient cohorts. Although follow-up appointments may provide mental health support, they can be inconvenient and not the ideal use of our healthcare resources. Our findings support a call for revision of existing skin cancer health policies to cope with and subsequently improve our practices for better patient care.

Management Approaches for High-Risk Cutaneous Squamous Cell Carcinoma with Perineural Invasion: An Updated Review

Cutaneous squamous cell carcinoma (cSCC) stands as the second most prevalent non-melanoma skin cancer worldwide, comprising approximately 20% of all cutaneous malignancies. Determining its precise incidence poses challenges; however, reports indicate a global increase in its prevalence. At the time of diagnosis, the majority of cSCCs are localized, resulting in favorable 5-year cure rates surpassing 90%. Nevertheless, a subset of patients (3-7%) encounters locally advanced or metastatic cSCC, leading to substantial morbidity and mortality. The risk of metastasis ranges from 0.1% to 9.9%, carrying an associated mortality risk of 2.8%. Factors influencing recurrence, metastasis, and disease-specific mortality underscore the significance of perineural invasion (PNI) as a key indicator. Patients with PNI may manifest clinical symptoms and/or radiologic signs of PNI, while the majority remain asymptomatic, and PNI is frequently identified upon histologic examination. Despite its lower frequency compared to other cancer types, PNI serves as a recognized adverse prognostic factor for cSCC. Surgery is the elective treatment for these patients, while the role of adjuvant radiotherapy (ART) is yet contentious and have not been conclusively assessed, particularly in clear surgical margin. Prospective comparative studies are required to comprehensively evaluate the benefit and the risks of ART for cSCC and PNI patients.

Reconceiving Perineural Invasion in Cutaneous Squamous Cell Carcinoma: From Biological to Histopathological Assessment

BACKGROUND

Perineural invasion (PNI) is a complex molecular process histologically represented by the presence of tumor cells within the peripheral nerve sheath and defined when infiltration into the 3 nerve sheath layers can be clearly identified. Several molecular pathways have been implicated in cSCC. PNI is a well-recognized risk factor in cutaneous squamous cell carcinoma (cSCC) and its accurate assessment represents a challenging field in pathology daily practice.

SUMMARY

As a highly intricate and dynamic process, PNI involves a contingent on bidirectional signaling interactions between the tumor and various nerve components, such as Schwann cells and neurons. The current staging systems recommend the identification of PNI as a dichotomous variable (presence vs. absence) to identify a subgroup of high-risk patients. However, recent further insights revealed that the evaluation of morphological PNI-related features in cSCC may enhance the prognostic stratification of patients and may optimize the current staging guidelines for recurrence risk assessment and improvement of patient selection for postoperative adjuvant treatments. Furthermore, recent emerging biomarkers could redefine early PNI detection.

KEY MESSAGES

This review provides updated insights into cSCC with PNI, focusing on molecular and cellular pathogenic processes, and aims to increase knowledge on prognostic relevant PNI-related histological features.

Impact of the COVID-19 Pandemic on the Surgical Management of Head and Neck Non-Melanoma Skin Cancers in a Maxillofacial Center of Cluj-Napoca

Background: The COVID-19 era has been a bleak period for both cancer and non-cancer patients, with delayed non-emergency treatments, such as for non-melanoma skin cancer (NMSC). This study aimed to evaluate how the treatment of NMSC patients was influenced by the management of the COVID-19 pandemic in an Eastern European Maxillofacial Surgery center. Materials and Methods: A total of 176 patients with a histopathological diagnosis of head and neck NMSC who were surgically treated in Cluj-Napoca Emergency County Hospital between 2016 and 2022 were included in this study, and divided into two samples, pre-pandemic (2016-2019) and COVID-19 (2020-2022) periods. Results: The pandemic presented with a decrease of 46.15% in patients' hospitalization, with wealthy and educated patients being prevalent. Even if the waiting time for surgery was increased, the stage of cancer and preference method for reconstruction did not differ. Despite the lower addressability of NMSC patients during the pandemic, there were no changes in surgical treatment. Conclusions: During COVID-19, the number of patients was reduced, with a longer waiting time for surgery, but without any changes in tumor stage and treatment preferences. However, the benefit of removing a cancer tumor is higher compared to the risk of developing COVID-19 infection during hospitalization.

Molecular and Histopathological Characterization of Metastatic Cutaneous Squamous Cell Carcinomas: A Case-Control Study

BACKGROUND

A subset of patients affected by cutaneous squamous cell carcinoma (cSCC) can exhibit locally invasive or metastatic tumors. Different staging classification systems are currently in use for cSCC. However, precise patient risk stratification has yet to be reached in clinical practice. The study aims to identify specific histological and molecular parameters characterizing metastatic cSCC.

METHODS

Patients affected by metastatic and non-metastatic cSCC (controls) were included in the present study and matched for clinical and histological characteristics. Skin samples from primary tumors were revised for several histological parameters and also underwent gene expression profiling with a commercially available panel testing 770 different genes.

RESULTS

In total, 48 subjects were enrolled in the study (24 cases, 24 controls); 67 genes were found to be differentially expressed between metastatic and non-metastatic cSCC. Most such genes were involved in immune regulation, skin integrity, angiogenesis, cell migration and proliferation.

CONCLUSION

The combination of histological and molecular profiles of cSCCs allows the identification of features specific to metastatic cSCC, with potential implications for more precise patient risk stratification.

Recent Changes in the Incidence and Characteristics of Cutaneous Squamous Cell Carcinomas in Finland from 2006 to 2020: A Retrospective Cohort Study

Registers recording only 1 tumour per patient do not enable assessment of the real burden of cutaneous squamous cell carcinoma. To investigate recent changes in the incidence and characteristics of tumours, a retrospective 15-year patient cohort study was performed in Finland. Histopathological diagnoses of cutaneous squamous cell carcinomas diagnosed between 2016 and 2020 were obtained from the pathology database and clinical data from patient medical records and combined with previously collected data for the years 2006-2015. Altogether 1,472 patients with 2,056 tumours were identified. The crude incidence increased from 19/100,000 persons in 2006 to 42 in 2020 (p < 0.001), increasing most in people aged over 80 years. The percentage of tumours located on the trunk increased from 5.3% during the first 5-year period, 2006-2010, to 9.0% in 2016-2020. Also, the location of tumours was significantly different between men and women, as men had more tumours on the scalp and ears, and women on the lower limbs. A slight change in the tumours from poorly to well differentiated and a decrease in the invasion depth were noted between 2006 and 2020. As the burden of tumours continues to increase, more attention should be paid to their prevention.

Long-term survival after anti-PD-1 discontinuation in advanced cutaneous squamous cell carcinoma (cSCC): a proof of concept of benefit of concomitant cemiplimab and radiotherapy

BACKGROUND

In a princeps study we conducted in patients with advanced cutaneous squamous cell carcinoma treated with concomitant anti-Programmed cell death protein 1 (PD-1) and radiotherapy, we demonstrated a clinico radiological response to cemiplimab that appeared to persist over time, 1 year after treatment discontinuation.

METHOD

We conducted a single-center descriptive study at Caen Hospital from September 1, 2021 to September 2023, in 14 patients with advanced carcinoma treated with cemiplimab until September 1, 2021. The aim of this update is to examine clinical and radiological follow-up 2 years after discontinuation of cemiplimab.

RESULTS

Of the 12 patients with a partial or complete response, we report 8 (66.7%) persistent responses 2 years after stopping cemiplimab, with only 2 patients progressing to distant disease, one lost to follow-up, and one death a priori unrelated to the disease.

CONCLUSION

Our study confirms a long-term and persistent effect despite discontinuation of cemiplimab at least up to 2 years later.

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.

Clinical Insights and Dermatological Recommendations for Non-Melanoma Skin Cancers (NMSCs) in Long-Term Hydroxyurea (HU) Therapy

Hydroxyurea (HU), an anti-metabolite ribonucleotide reductase inhibitor, is commonly used to treat several myeloproliferative disorders, including polycythemia vera. However, patients receiving long-term treatment with HU may experience a variety of cutaneous side effects, with non-melanoma skin cancers (NMSCs) emerging as the most challenging and destructive. HU-induced carcinogenesis can be attributed to both the drug's mutagenic potential and impaired DNA repair following damage by external triggers such as ultraviolet light. We report a unique case of multiple aggressive NMSCs distributed within sun-exposed areas in an 81-year-old woman receiving chronic therapy with HU for 15 years. The case draws the clinician's attention to the increased incidence of NMSCs in this population and highlights the need for regular dermatologic monitoring. We also elaborate relevant insights and recommendations to assist healthcare providers in managing HU-related NMSCs development and progression.