Cutaneous Squamous Cell Carcinoma: Review of the Eighth Edition of the American Joint Committee on Cancer Staging Guidelines, Prognostic Factors, and Histopathologic Variants

A Rare Case of Primary Cutaneous Basaloid Squamous Cell Carcinoma of the Finger

Abstract is missing (Short communication)

An unusual case of pilonidal p16 positive squamous cell carcinoma-a case report

Basaloid squamous cell carcinoma (BSCC) is a rare and aggressive variant of squamous cell carcinoma. It is commonly seen in the oropharynx and strongly associated with p16-expressivity and high-risk human papilloma virus (HPV). We report the first case of primary cutaneous p16-positive BSCC in an elderly woman, with a background of chronic inverse psoriasis of the natal cleft. P16-expressivity is a common surrogate marker for oncogenic HPV16, routinely tested for oropharyngeal/anogenital squamous cell carcinoma. This is not routinely done for primary cutaneous disease. Pilonidal disease is uncommon in the elderly population, and malignant transformation is rarer still. Surgical resection is considered the mainstay of treatment for primary cutaneous BSCC, however due to this patient's broad distribution of cutaneous field change and p16-expressivity, she was effectively treated with primary radiotherapy. This is a unique case of malignant transformation of pilonidal disease in an atypical demographic, with a rare/aggressive disease variant.

Cutaneous Squamous Cell Carcinoma: Clinico-Dermoscopic and Histological Correlation: About 72 Cases

INTRODUCTION

Cutaneous squamous cell carcinoma (cSCC) is the second most common skin cancer, accounting for 20% of malignant skin tumors. Dermoscopy is a very useful tool for diagnosing cSCC, and its findings are confirmed through histopathological studies.

OBJECTIVES

to describe the different dermoscopic structures of invasive cSCC and investigate their association with the clinical form and histopathological grade of differentiation.

METHODS

We conducted a cross-sectional study, collecting all patients diagnosed with squamous cell carcinoma over a period of 5 years. The study population was divided into two groups based on histological differentiation (well-differentiated and non-well-differentiated) and clinical form ( nodulo-ulcerative and nodular). Various dermoscopic parameters were compared between these groups.

RESULTS

Out of 72 invasive cSCC, 81.9% were well-differentiated, while 18.1% were non-well-differentiated. The clinical form of cSCC was nodulo-ulcerative in 83.3% of cases and nodular in 16.7%. Well-differentiated tumors showed dotted, glomerular and hairpin vessels, along with a predominant white pattern characterized by centrally distributed keratin as well as white circles, and whitish perivascular halo (P < 0.05). The distribution of these white structures was radial in nodulo-ulcerarive lesions, whereas in nodular lesions, their distribution, as well as that of keratin, was more diffuse (P < 0.05). Non-well-differentiated tumors showed a combined white-red pattern with the predominance of arborizing vessels (P < 0.05).

CONCLUSIONS

Our results show the reliability of dermoscopy as a tool for distinguishing between well- and poorly differentiated cSCC. This distinction is characterized by an increase in predominantly arborizing vessels and a corresponding decrease in white structures as the tumor progresses from a well-differentiated to a poorly differentiated state. Additionally, the nodulo-ulcerative form exhibits a central distribution of keratin, while the nodular form displays a diffuse distribution.

Skin Malignancies: Imaging Review with Radiologic-Histopathologic Correlation

Skin malignancies are commonly encountered as primary or incidental findings. Neoplasms that affect the skin include primary (basal cell carcinoma, squamous cell carcinoma, melanoma, and Merkel cell carcinoma) and secondary (mesenchymal neoplasms, lymphoma, and metastases) tumors. Imaging provides valuable anatomic information (tumor size, depth of involvement, presence of distant metastasis, and data for guiding biopsy) and functional information (metabolic activity and sentinel node mapping data). This information, in addition to biopsy results, improves the histopathologic characterization of tumors and treatment planning. Various histopathologic types of the same entity exhibit different biologic behavior and have different imaging features. Familiarity with the multimodality imaging features, histopathologic characteristics, and various modes of dissemination (direct invasion; perineural, lymphatic, and hematogenous spread) of the most common skin malignancies helps radiologists narrow the differential diagnosis in clinical practice. ©RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

European consensus-based interdisciplinary guideline for invasive cutaneous squamous cell carcinoma: Part 2. Treatment-Update 2023

In order to update recommendations on treatment, supportive care, education, and follow-up of patients with invasive cutaneous squamous cell carcinoma (cSCC), a multidisciplinary panel of 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 Organisation of Research and Treatment of Cancer (EORTC) was formed. Recommendations were based on an evidence-based literature review, guidelines, and expert consensus. Treatment recommendations are presented for common primary cSCC (low risk, high risk), locally advanced cSCC, regional metastatic cSCC (operable or inoperable), and distant metastatic cSCC. For common primary cSCC, the first-line treatment is surgical excision with postoperative margin assessment or micrographically controlled surgery. Achieving clear surgical margins is the most important treatment consideration for patients with cSCCs amenable to surgery. Regarding adjuvant radiotherapy for patients with high-risk localised cSCC with clear surgical margins, current evidence has not shown significant benefit for those with at least one high-risk factor. Radiotherapy should be considered as the primary treatment for non-surgical candidates/tumours. For cSCC with cytologically or histologically confirmed regional nodal metastasis, lymph node dissection is recommended. For patients with metastatic or locally advanced cSCC who are not candidates for curative surgery or radiotherapy, anti-PD-1 agents are the first-line systemic treatment, with cemiplimab being the first approved systemic agent for advanced cSCC by the Food and Drugs Administration/European Medicines Agency. Second-line systemic treatments for advanced cSCC, include epidermal growth factor receptor inhibitors (cetuximab) combined with chemotherapy or radiotherapy. Multidisciplinary board decisions are mandatory for all patients with advanced cSCC, considering the risks of toxicity, the age and frailty of patients, and co-morbidities, including immunosuppression. Patients should be engaged in informed, shared decision-making on management and be provided with the best supportive care to improve symptom management and quality of life. The frequency of follow-up visits and investigations for subsequent new cSCC depends on underlying risk characteristics.

Skin cancer prevention - Recent advances and unmet challenges

Cutaneous squamous cell carcinoma (cSCC) is the second most common malignancy in the world. Among many identified risk factors, immunosuppression is a major factor that contributes to cSCC development. Organ transplant recipients (OTRs) are at markedly increased risk of developing multiple cSCCs with a propensity for advanced metastatic disease, leading to significant morbidity and mortality. The severity of the cSCC phenotype in OTRs highlights the urgent need to identify effective preventive modalities in this population. Despite recent advances in skin cancer prevention (e.g., nicotinamide) and treatment (e.g., immune checkpoint blockade), these modalities have limited utility in OTRs due to the lack of efficacy or significant side effect. Topical treatments against precancerous skin lesions, actinic keratosis (AK), remain the primary strategy to prevent cSCC in OTRs, which also have significant deficiencies in this population. Herein, we review the epidemiology, risk factors, and current cSCC prevention strategies. We highlight the gaps and future clinical strategies to address cSCC risk in high-risk populations.

Perianal Cutaneous Spindle Cell Squamous Cell Carcinoma With Myxoid Stroma: Case Report and Literature Review

ABSTRACT

Spindle cell squamous cell carcinoma with myxoid stroma is a rare variant of squamous cell carcinoma with sarcomatoid morphology. We report a case of a 75-year-old woman with an ulcerated polypoid cutaneous mass in the perianal area. The patient had a history of clear cell renal cell carcinoma. Microscopy revealed an invasive myxoid spindle cell carcinoma without the classic squamous cell carcinoma component. The immunohistochemical study demonstrated diffuse positive reactions for p63, AE1/3, and CK5/6. The tumor cells were negative for desmin, smooth muscle actin, S100, and CD34. Fluorescent in situ hybridization was negative for EWSR1 gene rearrangement. Follow-up was remarkable for recurrence of tumor in 2 months after complete resection with negative surgical margin. This is the first case report of perianal spindle cell squamous cell carcinoma with myxoid stroma with a literature review of previous case reports from different locations.

Small intestinal perforation secondary to metastasis from skin squamous cell carcinoma: A case report and literature review

INTRODUCTION AND IMPORTANCE

Primary and metastatic carcinoma of the small intestine are rare. While most of these malignancies are adenocarcinomas, squamous cell carcinoma (SCC) of the gastrointestinal tract is uncommon. We present a case report of a rare occurrence of skin SCC metastasizing to the ileum, highlighting diagnostic challenges and clinical implications.

CASE PRESENTATION

An 83-year-old female had a history of cutaneous SCC excision in the right temporal region two years prior to the current emergency department visit, followed by metastatic recurrence in a right intra-parotid lymph node treated with radiotherapy. The patient exhibited septic shock and an acute abdomen, and an abdominal computed tomography scan revealed signs of intestinal perforation. Emergency exploratory laparotomy confirmed purulent peritonitis and perforation of the terminal ileum. Subsequently, a 20 cm intestinal resection was performed. Histopathological examination of the resected specimen revealed a 4 cm perforated SCC of the small intestine (pT4 pN0 L0 V1 Pn0 R0).

CLINICAL DISCUSSION

Metastases of the small intestine are rare. The primary sites for these metastases are typically the uterus, cervix, colon, lung, breast, or melanoma. SCC of the small intestine is particularly rare and poses challenges in diagnosis owing to non-specific symptoms. The prognosis for SCC of the small intestine is generally poor, and the potentially aggressive behavior of some skin SCC emphasizes the need for increased awareness and vigilance in managing such cases.

CONCLUSION

This case report underscores the importance of considering metastatic disease in the small bowel of patients with a history of skin SCC who present with new-onset abdominal symptoms.

Advancing Cancer Research: Current Knowledge on Cutaneous Neoplasia

Skin cancers require a multidisciplinary approach. The updated guidelines introduce new insights into the management of these diseases. Melanoma (MM), the third most common skin cancer, a malignant melanocytic tumor, which is classified into four major histological subtypes, continues to have the potential to be a lethal disease. The mortality-incidence ratio is higher in Eastern European countries compared to Western European countries, which shows the need for better prevention and early detection in Eastern European countries. Basal cell carcinoma (BCC) and squamous cell carcinoma (cSCC) remain the top two skin cancers, and their incidence continues to grow. The gold standard in establishing the diagnosis and establishing the histopathological subtype in BCC and SCC is a skin biopsy. Sebaceous carcinoma (SeC) is an uncommon and potentially aggressive cutaneous malignancy showing sebaceous differentiation. It accounts for 0.7% of skin cancers and 3-6.7% of cancer-related deaths. Due to the rapid extension to the regional lymph nodes, SeC requires early treatment. The main treatment for sebaceous carcinoma is surgical treatment, including Mohs micrographic surgery, which has the advantage of complete margin evaluation and low recurrence rates. Primary cutaneous lymphomas (PCLs) are a heterogeneous group of lymphoproliferative diseases, with no evidence of extracutaneous determination at the moment of the diagnosis. PCLs have usually a very different evolution, prognosis, and treatment compared to the lymphomas that may secondarily involve the skin. The aim of our review is to summarize the important changes in the approach to treating melanoma, non-melanoma skin, cutaneous T and B cell lymphomas, and other types of skin cancers. For all skin cancers, optimal patient management requires a multidisciplinary approach including dermatology, medical oncology, and radiation oncology.

Management of Non-Melanoma Skin Cancer: Radiologists Challenging and Risk Assessment

Basal cell carcinoma, squamous cell carcinoma, and Merkel cell carcinoma are the three main types of nonmelanoma skin cancers and their rates of occurrence and mortality have been steadily rising over the past few decades. For radiologists, it is still difficult to treat patients with advanced nonmelanoma skin cancer. Nonmelanoma skin cancer patients would benefit greatly from an improved diagnostic imaging-based risk stratification and staging method that takes into account patient characteristics. The risk is especially elevated among those who previously received systemic treatment or phototherapy. Systemic treatments, including biologic therapies and methotrexate (MTX), are effective in managing immune-mediated diseases; however, they may increase susceptibility to NMSC due to immunosuppression or other factors. Risk stratification and staging tools are crucial in treatment planning and prognostic evaluation. PET/CT appears more sensitive and superior to CT and MRI for nodal and distant metastasis as well as in surveillance after surgery. The patient treatment response improved with advent and utilization of immunotherapy and different immune-specific criteria are established to standardized evaluation criteria of clinical trials but none of them have been utilized routinely with immunotherapy. The advent of immunotherapy has also arisen new critical issues for radiologists, such as atypical response pattern, pseudo-progression, as well as immune-related adverse events that require early identification to optimize and improve patient prognosis and management. It is important for radiologists to have knowledge of the radiologic features site of the tumor, clinical stage, histological subtype, and any high-risk features to assess immunotherapy treatment response and immune-related adverse events.

LINC00460 Promotes Cutaneous Squamous Cell Carcinoma Progression Through Stabilizing ELAVL1 Protein

Long intergenic noncoding ribonucleic acid (lncRNA) 460 is reportedly associated with carcinogenesis and progression in various types of cancer. However, the mechanisms underlying its action in cutaneous squamous cell carcinoma (CSCC) remain unclear. LINC00460 mRNA expression was analysed using data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Cell growth, migration, and invasion were evaluated using Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), transwell migration and invasion assays after inducing LINC00460 knockdown. A xenograft tumour model was used to determine the effects of LINC00460 on tumour growth and metastasis in vivo. To examine the interaction between LINC00460 and ELAVL1, RNA pulldown and RNA immunoprecipitation assays were performed. LINC00460 was found to be significantly upregulated in CSCC tissues and cell lines. Functionally, LINC00460 knockdown inhibited cell proliferation, migration, and invasion in vitro. Consistent with this, when LINC00460 expression decreased, CSCC tumorigenesis and metastasis in vivo were inhibited. Mechanistically, LINC00460 binds to embryonic lethal abnormal vision like RNA binding protein 1 (ELAVL1) and enhances its stability by inhibiting the β-transducin repeats-containing protein (β-TrCP)-mediated ubiquitination of ELAVL1. Moreover, the effect of LINC00460 silencing on the proliferation, migration, and invasion of CSCC cells could be reversed by overexpressing ELAVL1. Our findings demonstrated that LINC00460 plays a critical role in regulating ELAVL1 function. This highlights the potential targets for the clinical diagnosis and treatment of CSCC.

A case of head and neck cutaneous squamous cell carcinoma highlighting aggressive perineural features

Cutaneous squamous cell carcinoma (cSCC) is the second most common nonmelanoma skin cancer in the United States following basal cell carcinoma. The majority are successfully cured by surgical excision or Mohs microsurgery. A subset of cSCCs are more aggressive and likely to recur locally, spread to regional lymph nodes or even distantly, and can even result in death. High-risk features of cSCC including perineural invasion of nerve >0.1 mm in diameter and invasion beyond the subcutaneous fat are not routinely reported by Mohs microsurgery. Facial cSCC commonly involves branches of the facial nerve (VII) or trigeminal nerve (V). Clinical symptoms associated with cranial nerve VII and V involvement include pain, paresthesia of the face and tongue, facial paralysis. Assessment of nerve involvement by magnetic resonance imaging (MRI) is the most optimal imaging modality. Here, we present a case where Mohs microsurgery was performed on a facial cSCC 1.5 years prior to the development of facial paresis. We aim to highlight the interesting perineural path resulting in facial paralysis and associated symptomatology, the importance of MRI, and to remind clinicians of important high-risk features of cSCC.

High-Dimensional and Spatial Analysis Reveals Immune Landscape-Dependent Progression in Cutaneous Squamous Cell Carcinoma

PURPOSE

The tumor immune microenvironment impacts the biological behavior of the tumor, but its effect on clinical outcomes in head and neck cutaneous squamous cell carcinomas (HNcSCC) is largely unknown.

EXPERIMENTAL DESIGN

We compared the immune milieu of high-risk HNcSCC that never progressed to metastasis with those that metastasized using multiparameter imaging mass cytometry. The cohort included both immunosuppressed patients (IS) and patients with an absence of clinical immune-suppression (ACIS). Spatial analyses were used to identify cellular interactions that were associated with tumor behavior.

RESULTS

Nonprogressing primary HNcSCC were characterized by higher CD8+ and CD4+ T-cell responses, including numerically increased regulatory T cells. In contrast, primary lesions from HNcSCC patients who progressed were largely devoid of T cells with lower numbers of innate immune cells and increased expression of checkpoint receptors and in the metastatic lesions were characterized by an accumulation of B cells. Spatial analysis reveals multiple cellular interactions associated with nonprogressing primary tumors that were distinct in primary tumors of disease-progressing patients. Cellular regional analysis of the tumor microenvironment also shows squamous cell-enriched tumor regions associated with primary nonprogressing tumors.

CONCLUSIONS

Effective responses from both CD8+ and CD4+ T cells in the tumor microenvironment are essential for immune control of primary HNcSCC. Our findings indicate that the early events that shape the immune responses in primary tumors dictate progression and disease outcomes in HNcSCC.

Antibody-Drug Conjugates for Melanoma and Other Skin Malignancies

OPINION STATEMENT

While most skin malignancies are successfully treated with surgical excision, advanced and metastatic skin malignancies still often have poor long-term outcomes despite therapeutic advances. Antibody-drug conjugates (ADCs) serve as a potentially promising novel therapeutic approach to treat advanced skin cancers as they combine antibody-associated antigen specificity with cytotoxic anti-tumor effects, thereby maximizing efficacy and minimizing systemic toxicity. While no ADCs have gained regulatory approval for advanced skin cancers, several promising agents are undergoing preclinical and clinical investigation. In addition to identifying and validating skin cancer antigen targets, the key to maximizing therapeutic success is the careful development of each component of the ADC complex: antibodies, cytotoxic drugs, and linkers. It is the optimization of each of these components that will be integral in overcoming resistance, maximizing safety, and improving long-term clinical outcomes.

Rare Mimic of a Myxofibrosarcoma: Cutaneous Myxoid Spindle Cell Squamous Cell Carcinoma as a Complication of Chronic Osteomyelitis

ABSTRACT

Myxoid spindle cell squamous cell carcinoma is a rare variant of squamous cell carcinoma that can pose diagnostic challenges because of its unusual morphology. In this article, we report the case of a 68-year-old man who presented with a slow-growing, fungating mass on the right tibia at the site of his long-standing draining sinus tract. Biopsy revealed a malignant spindle cell tumor with prominent myxoid stroma and areas containing thin-walled blood vessels with a curvilinear appearance. The immunohistochemical profile indicated that the neoplastic cells were positive for a variety of keratins (MNF116, Cam 5.2, AE1/AE3, 34βE12, and CK5/6) and transcriptional markers classically expressed in squamous cell carcinomas (p63 and p40). The tumor cells were negative for melanocytic and mesenchymal markers smooth muscle antibody, S100, caldesmon-h, desmin and CD34. Together, the clinical history, histologic appearance, and immunohistochemical panel was diagnostic of a myxoid spindle cell squamous cell carcinoma. The main differential diagnosis was myxofibrosarcoma. In addition to this clinical case, we also outline the current state of knowledge on this rare entity and discuss the importance of recognizing a Marjolin ulcer in this scenario.

Imaging findings of malignant skin tumors: radiological-pathological correlation

Sometimes, radiologists encounter malignant skin tumors (MSTs) during image interpretation. As MSTs require different clinical management modalities for each histological subtype, accurate preoperative diagnosis is essential. The histological subtypes of MST can be easily assessed by visual inspection or biopsy. Therefore, the significant role of radiological imaging in MSTs is to evaluate the extent of local invasion, nodal involvement, and distant metastasis, and the histological estimation of MSTs by radiological imaging has not been reported until a few years ago. However, recent studies have revealed characteristic radiological features for differential diagnosis of MSTs, such as configuration, intratumoral homogeneity, signal intensity, cyst formation, and hemorrhage. Other important clinical data for determining the histological subtype of MST include age, gender, and site of occurrence. MSTs can be categorized as epidermal, melanocytic, adnexal, and mesenchymal tumors based on the origin and have distinctive characteristics. Hence, this review article was designed to describe the clinical and radiological features of MSTs.

Evaluation of the Effect of Nutritional Intervention on Patients with Nasopharyngeal Carcinoma

Aim. The paper aims to combine mathematical statistics to assess the effect of nutritional intervention in the population of nasopharyngeal cancer patients. Methodology. After following the inclusion and exclusion criteria, a total of 120 patients with nasopharyngeal carcinoma were selected. All patients are treated with intensity-modulated radiotherapy (IMRT). The nurse collects relevant clinical treatment data during the radiotherapy of the patient. After the patient’s radiotherapy, the nurse remeasures the patient’s nutritional status indicators. Three months after the completion of radiotherapy, the patient will be reexamined by MRI, and the radiotherapist will assess the patient’s radiosensitivity based on the results of the MRI examination. All the blood biochemical indicators and body measurement indicators were also assessed and coordinated with nasopharyngeal carcinoma patients. This study performs multiple linear regression analysis on treatment-related factors that affect nutritional status during radiotherapy. Results. The experimental results showed that the side effects of radiotherapy are independent influencing factors of nutritional status. Radiotherapy damages the DNA of cells, so that cells cannot continue to divide and grow, and all cells in the treatment area were affected by radiation. The standard radiotherapy treatment is quite long, and the oral cavity, throat, and parotid gland, are all within the irradiation range. In addition to killing the tumor cells, the radiation can also cause certain damage to the surrounding tissues of the tumor. This article takes radiosensitivity as the dependent variable (insensitivity = 0; sensitivity = 1) and takes the nutritional index NI, age, gender, education level, marriage, smoking, chronic disease history, TNM staging, whether the chemotherapy steps are the same or not, GTVnx prescription dose, and the number of radiotherapies as independent variables. AMC, albumin, hemoglobin, serum prealbumin, and transferrin are all correlated with radiosensitivity, which is consistent with the results of most studies. The results of multivariate logistic regression analysis showed that nutritional index (NI) was correlated with the radiosensitivity of nasopharyngeal carcinoma. Conclusion. Finally, this paper concludes that nutritional intervention has a certain effect on the treatment of patients with nasopharyngeal carcinoma.

Porocarcinoma: an epidemiological, clinical, and dermoscopic 20-year study

BACKGROUND

Porocarcinoma (PC) is a rare cutaneous adnexal tumor with a variable metastatic potential. Given the paucity of data, guidelines and specific recommendations for PC are not yet well-established. In this study, we evaluate the disease-specific characteristics and outcome of this rare and often underestimated tumor.

MATERIALS AND METHOD

A retrospective study of the epidemiological, clinical, and dermoscopic characteristics among cases of histopathologically diagnosed PC, collected from the database of two skin cancer clinics in Italy (Firenze, Pistoia) from 2000 to 2020, was conducted.

RESULTS

Among the 52 patients with 53 tumors, 31 were men (59.6%) and 21 were women (40.4%) with an age range of 49-96 years (median age 82 years). The most common locations were the head/neck region in men (34% in men vs. 17% in women) and the lower limb in women (17% in women vs. 9% in men). Forty-eight cases (91%) underwent local excision. Of these patients, two (4%) experienced local recurrence, and one (2%) developed a second PC on a different anatomical site 1 month after the primary tumor's excision. Lymph node metastases were present in three cases (6%). Two of them have been treated surgically with adjuvant radiotherapy (both are disease-free after a 2-year follow-up period), whereas the third case developed visceral metastases followed by PC-related death.

CONCLUSIONS

This study, with 52 patients with 53 tumors covering a follow-up period of more than 5 years, shows a less aggressive behavior of PC with 4% local recurrence, 6% nodal metastases, and 2% mortality.

Redefining Perineural Invasion in Head and Neck Cutaneous Squamous Cell Carcinoma

OBJECTIVE

Perineural invasion (PNI) negatively affects disease-specific survival in patients with head and neck cutaneous squamous cell carcinoma (HNcSCC). We aim to analyze the prognostic implications of PNI-related features.

STUDY DESIGN

Retrospective cohort study.

SETTING

Academic tertiary care hospital.

METHODS

Retrospective chart review was performed on 104 patients diagnosed with HNcSCC between January 2011 and October 2019 who underwent resection, parotidectomy, and neck dissection with more than 1 year of follow-up. PNI was classified as incidental (identified on histopathology alone) or clinical (present on radiography and/or physical exam). Primary outcome measures were overall survival and disease-free survival (DFS). Kaplan-Meier analysis, logistic regression, and Cox regression were performed.

RESULTS

The overall 5-year DFS was 57.9%. Sixty-one patients had PNI. On histopathology, 28 lesions showed complete nerve encirclement, 10 involved >5 nerves, and 12 involved named nerves. Patients with facial weakness (P = .026) and positive margins (P = .0029) had a higher likelihood of histopathologic PNI, and positive margins retained significance on multivariable analysis (P = .0079). Worse DFS was seen in patients with PNI (P = .004), advanced tumor stage (P = .049), positive margins (P = .014), and >5 nerves involved (P = .0061). Furthermore, histopathologic PNI was a predictor of DFS (hazard ratio [HR], 3.07; 95% CI, 0.33-1.38; P = .0061) overall and in the clinical PNI cohort (HR, 3.43; 95% CI, 1.65-7.10; P = .00091).

CONCLUSION

DFS was significantly worse in patients with PNI, facial nerve weakness, advanced T stage, positive margins, and multiple nerve involvement. Further characterization of PNI features may help improve prognostic predictions and identify patients who may benefit from more aggressive treatment.

Antibody–Drug Conjugates as an Emerging Therapy in Oncodermatology

Simple Summary

Currently, the therapeutic arsenal to fight cancers is extensive. Among these, antibody–drug conjugates (ADCs) consist in an antibody linked to a cytotoxic agent, allowing a specific delivery to tumor cells. ADCs are an emerging class of therapeutics, with twelve FDA- and EMA-approved drugs for hematological and solid cancers. In recent years, tremendous progress has been observed in therapeutic approaches for advanced skin cancer patients. ADCs appear as an emerging therapeutic option in oncodermatology. After providing an overview of ADC design and development, the goal of this article is to review the potential ADC indications in the field of oncodermatology.

Abstract

Antibody–drug conjugates (ADCs) are an emerging class of therapeutics, with twelve FDA- and EMA-approved drugs for hematological and solid cancers. Such drugs consist in a monoclonal antibody linked to a cytotoxic agent, allowing a specific cytotoxicity to tumor cells. In recent years, tremendous progress has been observed in therapeutic approaches for advanced skin cancer patients. In this regard, targeted therapies (e.g., kinase inhibitors) or immune checkpoint-blocking antibodies outperformed conventional chemotherapy, with proven benefit to survival. Nevertheless, primary and acquired resistances as well as adverse events remain limitations of these therapies. Therefore, ADCs appear as an emerging therapeutic option in oncodermatology. After providing an overview of ADC design and development, the goal of this article is to review the potential ADC indications in the field of oncodermatology.

Cutaneous Squamous Cell Carcinoma: The Frontier of Cancer Immunoprevention

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer, with its incidence rising steeply. Immunosuppression is a well-established risk factor for cSCC, and this risk factor highlights the critical role of the immune system in regulating cSCC development and progression. Further highlighting the nature of cSCC as an immunological disorder, substantial evidence demonstrates a tight association between cSCC risk and age-related immunosenescence. Besides the proven efficacy of immune checkpoint blockade therapy for advanced cSCC, novel immunotherapy that targets cSCC precursor lesions has shown efficacy for cSCC prevention. Furthermore, the appreciation of the interplay between keratinocytes, commensal papillomaviruses, and the immune system has revealed the possibility for the development of a preventive cSCC vaccine. cSCC shares fundamental aspects of its origin and pathogenesis with mucosal SCCs. Therefore, advances in the field of cSCC immunoprevention will inform our approach to the management of mucosal SCCs and potentially other epithelial cancers.

Research on Correlations of miR-196a Expression with Progression and Prognosis of Cutaneous Squamous Cell Carcinoma

PURPOSE

This study aimed to investigate the correlation between miR-196a expression and the progression and prognosis of cutaneous squamous cell carcinoma (CSCC).

PATIENTS AND METHODS

Tissue samples and corresponding paracancerous tissue samples from 117 patients with CSCC were collected. The qRT-PCR analysis was used to detect the expression levels of miR-196a. Kaplan-Meier curve and Cox regression analyses were used to analyze the relationship between miR-196a expression and patients' prognosis. The CCK-8 and transwell assays were used to explore the effects of miR-196a on the abilities of cell proliferation, migration, or invasion.

RESULTS

miR-196a expression was significantly up-regulated in CSCC tissues or cell lines, compared with adjacent normal tissues or cell lines, respectively. High expression of miR-196a was associated with positive lymph node metastasis, high TNM stages, and a lower five-year survival rate. The expression level of miR-196a was up-regulated and the proliferation, migration or invasion ability of cells were significantly increased accordingly.

CONCLUSION

miR-196a is highly expressed in CSCC, thus affecting the occurrence and development of CSCC. More importantly, miR-196a was shown to have potential as a prognostic marker for CSCC.

The Multidisciplinary Management of Cutaneous Squamous Cell Carcinoma: A Comprehensive Review and Clinical Recommendations by a Panel of Experts

Cutaneous squamous cell carcinomas (CSCC) account for about 20% of all keratinocyte carcinomas, which are the most common form of cancer. Heterogeneity of treatments and low mortality are a challenge in obtaining accurate incidence data and consistent registration in cancer registries. Indeed, CSCC mostly presents as an indolent, low-risk lesion, with five-year cure rates greater than 90% after surgical excision, and only few tumors are associated with a high-risk of local or distant relapse; therefore, it is particularly relevant to identify high-risk lesions among all other low-risk CSCCs for the proper diagnostic and therapeutic management. Chemotherapy achieves mostly short-lived responses that do not lead to a curative effect and are associated with severe toxicities. Due to an etiopathogenesis largely relying on chronic UV radiation exposure, CSCC is among the tumors with the highest rate of somatic mutations, which are associated with increased response rates to immunotherapy. Thanks to such strong pre-clinical rationale, clinical trials led to the approval of anti-PD-1 cemiplimab by the FDA (Food and Drug Administration) and EMA (European Medicines Agency), and anti-PD-1 pembrolizumab by the FDA only. Here, we provide a literature review and clinical recommendations by a panel of experts regarding the diagnosis, treatment, and follow-up of CSCC.

Long non-coding RNA PICSAR serves as a non-invasive biomarker for the diagnosis and prognosis of cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) is one of the most common malignant tumors in dermatology, and its incidence is increasing year by year. Long non-coding RNAs (lncRNAs) play vital roles in the processes of various malignant tumors. This study aimed to evaluate the expression of long non-coding RNA PICSAR and investigate whether serum PICSAR could serve as a biomarker for the diagnosis and prognosis of cSCC. The expression level of PICSAR was measured using quantitative Real-Time PCR. The diagnostic value of PICSAR was evaluated by receiver operating characteristic (ROC) analysis. Survival curves were established using the Kaplan-Meier method, and the log-rank test was used to compare differences between the two curves. Prognostic value of PICSAR was confirmed by Cox regression analysis. The expression of PICSAR was upregulated in serum of cSCC patients and tumor tissues of patients. Additionally, serum PICSAR expression had relatively high diagnostic accuracy for the screening of cSCC. Moreover, PICSAR expression was correlated with tumor size, grade of differentiation and TNM stages, and significantly increased in cSCC patients with poor tumor differentiation and cSCC patients with III-IV TNM stage. Furthermore, patients with high PICSAR expression had lower overall survival than the patients with low PICSAR expression, and PICSAR expression was an independent prognostic factors for cSCC patients. The results of this study indicated that PICSAR was upregulated in cSCC patients and tumor tissues and might serve as a non-invasive biomarker for the diagnosis and prognosis of cSCC patients.

Lack of documentation of lymph node examination in patients with squamous cell carcinoma of the lower lip

Cutaneous squamous cell carcinoma is the second most common cutaneous malignancy with a 5-year disease-specific survival rate of approximately 90%, which decreases dramatically to 50% in the presence of regional lymph node metastases. We sought to examine clinicians' documentation of pertinent neurological symptoms/signs and lymph node palpation at the time of initial biopsy and treatment using lower lip SCC patients as a cohort. Subsequently, we investigated the correlation between clinical and pathologic SCC features and the aforementioned documentation. A single center, retrospective study of all squamous cell carcinomas of the lower lip biopsied over 10 years was conducted, and univariate models were implemented to correlate the variables. A total of 66 squamous cell carcinomas of the lip in 63 patients were identified. Neurological signs and symptoms were not documented and only three of the tumors were palpated, therefore statistical analysis was not performed. A lymph node exam was documented in 14 of the 63 patients (22%), and statistical analysis showed that among all variables (age, gender, tumor size, tumor stages, tobacco or alcohol use, or history of skin cancer), only the size of the tumor correlated positively with a lymph node examination (RRE 1.15 [95% CI 1.06-1.25], p < 0.001). Our study illustrates a possible practice gap and quality improvement potential in tumor, neurologic, and lymph node examination and documentation in patients with cutaneous squamous cell carcinoma.

New Developments in the Management of Cutaneous Squamous Cell Carcinoma

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. List important prognostic features that affect cutaneous squamous cell carcinoma risk. 2. Summarize the changes to the AJCC Cancer Staging Manual, Eighth Edition, staging system for cutaneous squamous cell carcinoma. 3. Evaluate the draining nodal basin with appropriate imaging modalities. 4. Recommend adjuvant radiation therapy in the correct clinical setting for high-risk tumors. 5. Recognize the currently available treatments for advanced cutaneous squamous cell carcinoma.

SUMMARY

This continuing medical education article reviews the features, management, and prognosis of cutaneous squamous cell carcinoma with an emphasis on high-risk squamous cell carcinoma and data from the past 3 years. This review will discuss the primary tumor management, high-risk features of a squamous cell carcinoma, changes to the American Joint Committee on Cancer staging system, and the utility of sentinel lymph node biopsy, and critically review the evidence regarding adjuvant therapy.

Crocin exerts anti-proliferative and apoptotic effects on cutaneous squamous cell carcinoma via miR-320a/ATG2B

Cutaneous squamous cell carcinoma (cSCC) is a highly prevalent skin malignancy, and the effective therapy still remains a challenge. Crocin can be used for cSCC therapy. This study explored the effects of cSCC cells treatment with crocin in vitro and in vivo. The study used A431 and SCL-1 cells lines, cSCC human samples and BALB/C nude mice for investigations. Apoptosis was determined by MTT assays, while miR-320a and ATG2B expressions were validated through RT-qPCR. Interaction of miR-320a with ATG2B was examined via dual luciferase reporter assay. The autophagy and apoptosis proteins expressions were further confirmed through western blot and immunofluorescence staining assays. The results indicated a significantly upregulated miR-320a, but a down-regulated ATG2B expression in the cSCC clinical samples. Crocin significantly repressed cSCC cells growth, and induced apoptosis through autophagy. Furthermore, miR-320a expression was inhibited and ATG2B expression was increased. Dual luciferase reporter assay revealed that miR-320a regulated ATG2B expression directly. Additionally, the upregulation of ATG2B expression in cSCC cells inhibited cell proliferation and led to cell apoptosis. Crocin also reduced tumor growth and stimulated the apoptosis in vivo. In conclusion, miR-320a is upregulated and ATG2B is down-regulated in cSCC, Crocin suppresses the proliferation and induces apoptosis of cSCC cells. Further, Crocin increases autophagy while miR-320a hinders autophagy and the apoptotic effects of crocin on cSCC cells. MiR-320a binds ATG2B directly, and ATG2B expression is upregulated by crocin. Finally, Crocin triggers cSCC cells apoptosis in vivo. Crocin can target ATG2B/miR-320a and may be an effective alternative for cSCC treatment.

Clinician perspectives on the factors influencing prognostic stratification by the American Joint Commission on Cancer Head and Neck Cutaneous Squamous Cell Carcinoma Staging

BACKGROUND

The eighth edition of the American Joint Committee on Cancer Staging Manual includes a staging system for head and neck cutaneous squamous cell carcinoma for the first time. The pN categories for head and neck cutaneous squamous cell carcinoma and mucosal squamous cell carcinoma are identical, despite the vastly different biological behavior of these diseases. This study aimed to survey head and neck cancer specialists' views regarding the clinical utility of the American Joint Committee on Cancer Staging Manual for head and neck cutaneous squamous cell carcinoma and to identify avenues for improvement.

DESIGN

An electronic survey of 19 questions relating to the prognostic utility of the staging system was designed based on the findings of a literature review. The survey was distributed internationally to specialists managing head and neck cutaneous squamous cell carcinoma.

RESULTS

Literature review identified 9 articles describing primary research relevant to the performance of the American Joint Committee on Cancer Staging Manual for head and neck cutaneous squamous cell carcinoma, which recognized a lack of homogeneity, monotonicity, and distinctiveness in the pN staging system. One hundred and five survey responses were received: 71% indicated that mucosal and head and neck cutaneous squamous cell carcinoma require different nodal staging categories; 63% indicated that immunosuppression should be included in the staging system; 70% thought that soft tissue metastases portend a worse prognosis compared with extranodal extension; 38% almost never saw pN3a tumors; and 40% felt that the N stage is a poor predictor of survival.

CONCLUSION

The views of head and neck cancer specialists across disciplines and countries align with evidence suggesting that head and neck cutaneous squamous cell carcinoma merits a staging system distinct from mucosal squamous cell carcinoma, that immunosuppression should be considered in prognostication, and that the use of extranodal extension should be modified.

Identifying an lncRNA-Related ceRNA Network to Reveal Novel Targets for a Cutaneous Squamous Cell Carcinoma

Simple Summary

The exact functions and molecular mechanism of lncRNAs, acting as competitive endogenous RNAs in a cutaneous squamous cell carcinoma, remain unexplored. The present study was conducted to identify the differentially expressed lncRNAs and mRNAs and establish the lncRNA-related competing endogenous RNA networks associated with a cutaneous squamous cell carcinoma. A competing endogenous RNA network consisting of 137 miRNA-lncRNA and 221 miRNA-mRNA pairs was constructed. As for the functional analysis of the mRNAs in the network, a FoxO signaling pathway, an autophagy and cellular senescence were the top enrichment terms based on the Kyoto Encyclopedia of Genes and Genomes analysis. We identified five core mRNAs and built a core mRNA-associated competing endogenous RNA network. Finally, one lncRNA HLA-F-AS1 and three mRNAs named AGO4, E2F1 and CCND1 in the core mRNA-associated competing endogenous RNA network were validated with the same expression patterns. The core mRNAs and their associated lncRNAs may provide potential therapeutic targets for cutaneous squamous cell carcinomas.

Abstract

A cutaneous squamous cell carcinoma (cSCC) derived from keratinocytes is the second most common cause of non-melanoma skin cancer. The accumulation of the mutational burden of genes and cellular DNA damage caused by the risk factors (e.g., exposure to ultraviolet radiation) contribute to the aberrant proliferation of keratinocytes and the formation of a cSCC. A cSCC encompasses a spectrum of diseases that range from recursor actinic keratosis (AK) and squamous cell carcinoma (SCC) in situ (SCCIS) to invasive cSCCs and further metastatic SCCs. Emerging evidence has revealed that lncRNAs are involved in the biological process of a cSCC. According to the ceRNA regulatory theory, lncRNAs act as natural miRNA sponges and interact with miRNA response elements, thereby regulating the mRNA expression of their down-stream targets. This study was designed to search for the potential lncRNAs that may become potential therapeutic targets or biomarkers of a cSCC. Considering the spirit of the study to be adequately justified, we collected microarray-based datasets of 19 cSCC tissues and 12 normal skin samples from the GEO database (GSE42677 and GSE45164). After screening the differentially expressed genes via a limma package, we identified 24 differentially expressed lncRNAs (DElncRNAs) and 3221 differentially expressed mRNAs (DEmRNAs). The miRcode, miRTarBase, miRDB and TargetScan databases were used to predict miRNAs that could interact with DElncRNAs and DEmRNAs. A total of 137 miRNA-lncRNA and 221 miRNA-mRNA pairs were retained in the ceRNA network, consisting of 31 miRNAs, 11 DElncRNAs and 155 DEmRNAs. For the functional analysis, the top enriched biological process was enhancer sequence-specific DNA binding in Gene Ontology (GO) terms. The FoxO signaling pathway, autophagy and cellular senescence were the top enrichment terms based on a Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The combination of a STRING tool and Cytoscape software (plug-in MCODE) identified five core mRNAs and built a core mRNA-associated ceRNA network. The expression for five identified core mRNAs and their related nine lncRNAs was validated using the external dataset GSE7553. Finally, one lncRNA HLA-F-AS1 and three mRNAs named AGO4, E2F1 and CCND1 were validated with the same expression patterns. We speculate that lncRNA HLA-F-AS1 may sponge miR-17-5p or miR-20b-5p to regulate the expression of CCND1 and E2F1 in the cSCC. The present study may provide potential diagnostic and therapeutic targets for cSCC patients.

Identifying Susceptibility Loci for Cutaneous Squamous Cell Carcinoma Using a Fast Sequence Kernel Association Test

Cutaneous squamous cell carcinoma (cSCC) accounts for about 20% of all skin cancers, the most common type of malignancy in the United States. Genome-wide association studies (GWAS) have successfully identified multiple genetic variants associated with the risk of cSCC. Most of these studies were single-locus-based, testing genetic variants one-at-a-time. In this article, we performed gene-based association tests to evaluate the joint effect of multiple variants, especially rare variants, on the risk of cSCC by using a fast sequence kernel association test (fastSKAT). The study included 1,710 cSCC cases and 24,304 cancer-free controls from the Nurses' Health Study, the Nurses' Health Study II and the Health Professionals Follow-up Study. We used UCSC Genome Browser to define gene units as candidate loci, and further evaluated the association between all variants within each gene unit and disease outcome. Four genes HP1BP3, DAG1, SEPT7P2, and SLFN12 were identified using Bonferroni adjusted significance level. Our study is complementary to the existing GWASs, and our findings may provide additional insights into the etiology of cSCC. Further studies are needed to validate these findings.

Pathogenesis of Keratinocyte Carcinomas and the Therapeutic Potential of Medicinal Plants and Phytochemicals

Keratinocyte carcinoma (KC) is a form of skin cancer that develops in keratinocytes, which are the predominant cells present in the epidermis layer of the skin. Keratinocyte carcinoma comprises two sub-types, namely basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). This review provides a holistic literature assessment of the origin, diagnosis methods, contributing factors, and current topical treatments of KC. Additionally, it explores the increase in KC cases that occurred globally over the past ten years. One of the principal concepts highlighted in this article is the adverse effects linked to conventional treatment methods of KC and how novel treatment strategies that combine phytochemistry and transdermal drug delivery systems offer an alternative approach for treatment. However, more in vitro and in vivo studies are required to fully assess the efficacy, mechanism of action, and safety profile of these phytochemical based transdermal chemotherapeutics.

Roles of the H19/microRNA‑675 axis in the proliferation and epithelial‑mesenchymal transition of human cutaneous squamous cell carcinoma cells

The long non-coding RNA (lncRNA) H19 and microRNA(miR)-675 were reported to serve an important role in the tumorigenesis and metastasis of numerous cancer types by promoting the epithelial-mesenchymal transition (EMT) process; however, the underlying mechanisms of action of H19 and miR-675 in cutaneous squamous cell carcinoma (cSCC) remain unknown. The mRNA expression levels of H19 and miR-675 were analyzed using reverse transcription-quantitative PCR, and Cell Counting Kit-8, wound healing and Transwell assays were performed to analyze the cell proliferation, migration and invasion of cSCC cells, respectively. The levels of cell apoptosis were also determined using a TUNEL assay. Protein expression levels of p53 and marker proteins related to the EMT process were analyzed using western blotting. In addition, a dual luciferase reporter assay was performed to determine the interactions between H19, miR-675 and p53. The results of the present study revealed that the expression levels of H19 and miR-675 were upregulated in cSCC tissues and cSCC cell lines. The knockdown of H19 or miR-675 expression inhibited cell proliferation, migration and invasion, but induced cell apoptosis. In addition, the expression levels of EMT-related markers were also downregulated. The overexpression of H19 upregulated the expression levels of its predicted target, miR-675, which subsequently promoted the EMT process and downregulated the expression levels of p53. Conversely, the genetic silencing of H19 or miR-675 inhibited proliferation and invasion in SCL1 and A431 cSCC cell lines. In conclusion, the findings of the present study provided novel insight into the potential role of H19 and miR-675 in the development, metastasis and progression of cSCC, which may help the development of treatments for cSCC.

Cutaneous Squamous Cell Carcinoma: From Pathophysiology to Novel Therapeutic Approaches

Cutaneous squamous cell carcinoma (cSCC), a non-melanoma skin cancer, is a keratinocyte carcinoma representing one of the most common cancers with an increasing incidence. cSCC could be in situ (e.g., Bowen’s disease) or an invasive form. A significant cSCC risk factor is advanced age, together with cumulative sun exposure, fair skin, prolonged immunosuppression, and previous skin cancer diagnoses. Although most cSCCs can be treated by surgery, a fraction of them recur and metastasize, leading to death. cSCC could arise de novo or be the result of a progression of the actinic keratosis, an in situ carcinoma. The multistage process of cSCC development and progression is characterized by mutations in the genes involved in epidermal homeostasis and by several alterations, such as epigenetic modifications, viral infections, or microenvironmental changes. Thus, cSCC development is a gradual process with several histological- and pathological-defined stages. Dermoscopy and reflectance confocal microscopy enhanced the diagnostic accuracy of cSCC. Surgical excision is the first-line treatment for invasive cSCC. Moreover, radiotherapy may be considered as a primary treatment in patients not candidates for surgery. Extensive studies of cSCC pathogenic mechanisms identified several pharmaceutical targets and allowed the development of new systemic therapies, including immunotherapy with immune checkpoint inhibitors, such as Cemiplimab, and epidermal growth factor receptor inhibitors for metastatic and locally advanced cSCC. Furthermore, the implementation of prevention measures has been useful in patient management.

Challenges and new perspectives in the treatment of advanced cutaneous squamous cell carcinoma

Despite the overall excellent survival rates in patients affected by early cutaneous squamous cell carcinoma (CSCC), advanced forms of CSCC are associated with high patient mortality. To date, only limited therapeutic modalities have been implemented, including chemotherapy and radiotherapy. Systemic therapy was enriched by the addition of epidermal growth factor receptor inhibitors (EGFRi) in the last years. Unfortunately, the overall outcome of all these therapeutic strategies remains poor, therefore important unmet clinical needs persist. Thanks to a better understanding of the biology of advanced CSCC, new treatment options are now available. This article presents the current definition of advanced CSCC along with actual therapeutic options and discusses the strengths and limitations of a new promising systemic approach, which involves the use of immune checkpoint inhibitors.

Risk factors and timing of subsequent cutaneous squamous cell carcinoma in patients with cutaneous squamous cell carcinoma: A retrospective cohort study

BACKGROUND

Information about the frequency and timing of subsequent cutaneous squamous cell carcinoma (cSCC), along with associated risk factors, is limited. However, this information is crucial to guide follow-up care for these patients.

OBJECTIVE

To evaluate the risk and timing of subsequent cSCC in patients who presented with an initial diagnosis of cSCC.

METHODS

Retrospective review of an institutional review board-approved, single-institution registry of invasive cSCC. All patients had at least 2 primary cSCCs diagnosed on 2 separate dates 2 months apart.

RESULTS

A total of 299 primary cSCCs were included. At 6 months from initial cSCC diagnosis, 18.06% (n = 54) of patients developed subsequent cSCC; at 1 year, 31.77% (n = 94); at 3 years, 67.56% (n = 202); and at 5 years, 87.96% (n = 263) developed subsequent cSCC. Risk factors associated with subsequent cSCC include age at initial diagnosis (hazard ratio [HR], 1.02; 95% confidence interval, 1.004-1.027; P = .008), T2 stage (HR, 1.66; 95% CI, 1.07-2.57; P = .025), and poor tumor grade. Tumor grades well, moderate, and unknown have HRs of 0.21 (P < .001), 0.16 (P .001), and 0.25 (P = .001), respectively.

CONCLUSIONS

Of patients who develop subsequent cSCC, 18.06% do so within 6 months, and 31.77% do so within 1 year of initial cSCC diagnosis. Patients with advanced age, poor histologic differentiation, and American Joint Committee on Cancer T2 stage are at highest risk. Close clinical follow-up after the initial diagnosis is recommended.

[Cutaneous squamous cell carcinoma]

Cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers of the Caucasian population and accounts for 20% of all skin tumours. An S3 guideline of the German Guideline Program in Oncology has been available since 2019. The diagnosis is based on the clinical examination. Excision and histological confirmation is required for all clinically suspicious lesions to allow prognostic assessment and correct treatment. The therapy of first choice is complete excision with histological control of the surgical margin. In cSCC with risk factors such as tumor thickness >6 mm, sentinel lymph node biopsy may be discussed, but there is currently no clear evidence of its prognostic and therapeutic relevance. Adjuvant radiation therapy may be considered in cases of high risk of recurrence and should be tested in cases of inoperable tumors. The indication for electrochemotherapy should also be considered in the treatment of local or locoregional recurrence. The immune checkpoint inhibitor cemiplimab is approved for the treatment of inoperable or metastasized cSCC. In case of contraindications, chemotherapeutic agents, epidermal growth factor receptor (EGFR) inhibitors or palliative radiotherapy can be used. Since the evidence is low in these cases, a systemic therapy should be used preferentially within clinical studies. Follow-up care should be risk-adapted and includes a dermatological control, supplemented by ultrasound examinations in high-risk patients.

Cutaneous HPV16 and p16 Positive Basaloid Squamous Cell Carcinoma with Brain Metastasis: A Case Report

Basaloid squamous cell carcinoma is an infiltrative and aggressive variant of squamous cell carcinoma with basaloid features. Primary skin-derived basaloid squamous cell carcinoma is rare. Basaloid squamous cell carcinoma is commonly observed in the oropharyngeal and anogenital regions and is associated with high-risk human papillomavirus. We report a case of primary basaloid squamous cell carcinoma overlying the right scapula with metastasis to the regional lymph nodes and brain despite surgical resection and adjuvant chemoradiation. Histopathologic investigations of high-risk cutaneous squamous cell carcinoma do not routinely involve human papillomavirus testing. In contrast, oncogenic human papillomavirus and p16 are screened in head and neck squamous cell carcinoma for prognostication. Since the patient presented with an aggressive variant of squamous cell carcinoma and distal metastasis despite standard therapies, human papillomavirus testing was performed. P16, a surrogate marker for human papillomavirus infection and specifically HPV16 was identified in the tumor. This is a unique report of HPV16 in primary cutaneous basaloid squamous cell carcinoma with distal brain metastasis.

Cutaneous squamous cell carcinoma in the organ transplant recipient

One in twenty solid organ transplant recipients (SOTRs) will develop a highly morbid or fatal cutaneous carcinoma after transplantation. The majority of these cases develop on the head and neck and may require intervention on the part of dermatology, dermatologic surgery, otolaryngology, transplant medicine, radiation oncology, and medical oncology. In this review, we discuss the problem of cutaneous squamous cell carcinoma (cSCC) in SOTRs as well as the prognostic factors and management strategies to care for this population.

The Roles of lncRNA in Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma derives from keratinocytes and is the second most common cause of non-melanoma skin cancer. Cutaneous squamous cell carcinoma (cSCC) develops rapidly and is also the leading cause of death in non-melanoma cancers. Lymph node metastasis occurs in 5% of cSCC patients, and some patients may even metastasize to the viscera. Patients with regional lymphatic metastasis or distant metastases have a <20% 10-year survival rate, indicating the substantial challenge in treating advanced and metastatic cSCC. Some lncRNAs have been found to be abnormally overexpressed in many tumor tissues, so that they can be considered as potential new biomarkers or targets that can be used in the diagnosis and treatment of cSCC in the future. In this review, we summarize the role of lncRNA in cutaneous squamous cell carcinoma to make a better understanding of mutations in cSCC and lay the foundation for effective target therapy of cSCC.

European interdisciplinary guideline on invasive squamous cell carcinoma of the skin: Part 2. Treatment

In order to update recommendations on treatment, supportive care, education and follow-up of patients with invasive cutaneous squamous cell carcinoma (cSCC), a multidisciplinary panel of experts from the European Dermatology Forum, the European Association of Dermato-Oncology and the European Organization of Research and Treatment of Cancer was formed. Recommendations were based on evidence-based literature review, guidelines and expert consensus. Treatment recommendations are presented for common primary cSCC (low risk, high risk), locally advanced cSCC, regional metastatic cSCC (operable or inoperable) and distant metastatic cSCC. For common primary cSCC (the most frequent cSCC type), first-line treatment is surgical excision with postoperative margin assessment or microscopically controlled sugery. Safety margins containing clinical normal-appearing tissue around the tumour during surgical excision and negative margins as reported in the pathology report are necessary to minimise the risk of local recurrence and metastasis. In case of positive margins, a re-excision shall be done, for operable cases. Lymph node dissection is recommended for cSCC with cytologically or histologically confirmed regional nodal involvement. Radiotherapy should be considered as curative treatment for inoperable cSCC, or for non-surgical candidates. Anti-PD-1 antibodies are the first-line systemic treatment for patients with metastatic or locally advanced cSCC who are not candidates for curative surgery or radiation, with cemiplimab being the first approved systemic agent for advanced cSCC by the Food and Drug Administration/European Medicines Agency. Second-line systemic treatments for advanced cSCC include epidermal growth factor receptor inhibitors (cetuximab) combined with chemotherapy or radiation therapy. Multidisciplinary board decisions are mandatory for all patients with advanced disease who require more than surgery. Patients should be engaged with informed decisions on management and be provided with best supportive care to optimise symptom management and improve quality of life. Frequency of follow-up visits and investigations for subsequent new cSCC depend on underlying risk characteristics.

Case report of a 65-year-old man with biatrial metastatic localisation from poorly differentiated cutaneous squamous cell carcinoma

We report the case of an immunocompetent 65-year-old man affected by cutaneous squamous cell carcinoma (cSCC) with lung and biatrial metastatic localisation. In May 2018, the patient underwent lower limb amputation due to the finding of a large ulceration which upon biopsy was found to be a poorly differentiated squamous cell carcinoma (SCC), ulcerated, full-thickness infiltrating from the skin to the underlying bone tissue. After 1 month, a radiological restaging found multiple pulmonary localisations and a right-atrial metastatic localisation. The patient was then studied in-depth and a transesophageal echocardiogram found that the patient had two 2 and 5 cm metastatic localisations in the left atrium and a 3-cm metastatic localisation in the right atrium. Informed about the clinical situation and about the risks of a chemotherapeutic treatment, the patient decided not to start any treatment. This case represents, to our knowledge, the only case of a biatrial metastatic localisation from cSCC and is representative of how cardiac symptoms and signs in patients affected by this disease must be evaluated.

Reconstruction of a dorsal thoracic wall defect with a dorsal intercostal artery perforator flap after removal of a bulky cutaneous squamous cell carcinoma: a case report

Introduction

Surgical reconstruction of large soft tissue defects of the upper back is challenging. Although the usefulness of free perforator flaps has been demonstrated, local options remain limited. The dorsal intercostal artery perforator flap was recently described but its use is still uncommon.

Case report

An 88-year-old Causasian woman presented with a large, ulcerated, left prescapular cutaneous squamous cell carcinoma (T3N0M0). Complete excision was performed, and the resulting defect was reconstructed with a dorsal intercostal artery perforator flap based on two perforators. Postoperative recovery was uncomplicated and adjuvant radiotherapy commenced 10 weeks later.

Conclusion

Compared to conventional muscle flaps, the dorsal intercostal artery perforator flap offers greater protection of muscle function, is less invasive, and lowers donor site morbidity. Based on these advantages, this flap should be considered a useful local option for reconstructing large cutaneous defects of the upper back.

Prognostic value of inositol polyphosphate-5-phosphatase expression in recurrent and metastatic cutaneous squamous cell carcinoma

BACKGROUND

Inositol polyphosphate-5-phosphatase (INPP5A) has been shown to play a role in the progression of actinic keratosis to cutaneous squamous cell carcinoma (cSCC) and the progression of localized disease to metastatic disease. Currently, no cSCC biomarkers are able to risk stratify recurrent and metastatic disease.

OBJECTIVE

To determine the prognostic value of INPP5A expression in cSCC recurrent and metastatic disease.

METHODS

We conducted a multicenter, single-institutional, retrospective cohort study within the Mayo Clinic Health System on the use of immunohistochemical staining to examine cSCC INPP5A protein expression in primary tumors and recurrent and metastatic disease. Dermatologists and dermatopathologists were blinded to outcome.

RESULTS

Low staining expression of INPP5A in recurrent and metastatic disease tumors was associated with poor overall survival (OS) (31.0 months for low versus 62.0 months for high expression; P = .0272). A composite risk score (calculated as score of primary tumor + score of recurrent or metastatic disease tumor, with tumors with high expression scoring a zero and low expression a 1, score range 0-2) of 0 was predictive of improved OS compared with a composite risk score of ≥1 (hazard ratio 0.42, 95% confidence interval 0.21-0.84; P = .0113).

LIMITATIONS

This is a multicenter but single institution study of a white population.

CONCLUSION

Loss of INPP5A expression predicts poor OS in recurrent and metastatic disease of cSCC.

Toll‑like receptor 4 plays a tumor‑suppressive role in cutaneous squamous cell carcinoma

Toll‑like receptor 4 (TLR4), a key regulator of the innate immune system, is expressed not only in immune cells, but also in a number of cancer cells. A biological role for TLR4 in cutaneous squamous cell carcinoma (SCC), however, is unclear. In this study, we first examined TLR4 expression and localization in cases of SCC, actinic keratosis (AK) and Bowen's disease (BD) by immunohistochemistry. TLR4 expression was significantly higher in the SCC than in the AK or BD tissues. We then determined the TLR4 expression level in vivo, in 3 histological subtypes of SCC. TLR4 expression in poorly differentiated SCC was significantly lower compared with that of the moderately and well‑differentiated type. In addition, the CD44 immunoreactivity tended to be high in the cell membrane of poorly differentiated SCC. Of note, poorly differentiated SCC is a risk factor of unfavorable outcomes in affected patients. We then assessed the biological role of TLR4 in HSC‑1 and HSC‑5 SCC cells and HaCaT human keratinocytes. TLR4 knockdown by transfection with siRNA accelerated HSC‑1 and HaCaT cell migration and invasion compared to the control siRNA‑transfected cells. TLR4 knockdown resulted in an increased CD44 expression and in an enhanced filopodia protrusion formation, particularly in HSC‑1. On the whole, these results suggest that a reduced TLR4 expression enhances the malignant features in SCC cases and cultured SCC cell lines. TLR4 may thus play an anti‑tumor role in cutaneous SCC.

Uncommon Presentation of Metastatic Squamous Cell Carcinoma of the Skin and Treatment Challenges

Patient: Female, 80

Final Diagnosis: Metastatic squamous cell carcinoma of skin

Symptoms: Back pain • leg swelling • uti

Medication: —

Clinical Procedure: Immunotherapy

Specialty: Oncology

The prognostic value of inositol polyphosphate 5-phosphatase in cutaneous squamous cell carcinoma

BACKGROUND

Inositol polyphosphate 5-phosphatase (INPP5A) has been shown to play a role in development and progression of cutaneous squamous cell carcinoma (cSCC). The goal of the current study was to explore the prognostic value of INPP5A expression in cSCC.

METHODS

A total of 189 cases of actinic keratosis and SCC in 174 patients were identified; clinical and outcome data were abstracted, histopathology was rereviewed, and immunohistochemical staining and interpretation was performed for INPP5A.

RESULTS

The majority of tumors (89.4%) had an INPP5A score of 2 or 3. No patients had complete loss of INPP5A. Tumors with an INPP5A score of 1 were more likely to be intermediate- to high-risk tumors (Brigham and Women's Hospital stage ≥T2a 85.0% vs 23.7% [P < .0001]) characterized by a larger diameter (2.4 cm vs 1.3 cm [P = .0004]), moderate-to-poor differentiation (86.7% vs 17.6% [P < .0001]), and perineural invasion (37.5% vs 5.3%, [P < .0001]). An INPP5A score of 1 was associated with a worse 3-year survival (a rate of 42.3% [hazard ratio, 2.81, P = .0006]) and a local metastasis rate of 48.0% (hazard ratio, 4.71; P < .0001).

CONCLUSIONS

Low INPP5A scores are predictive of aggressive tumors and may be a useful adjunct to guide clinical management of cSCC.