Nationwide Incidence of Metastatic Cutaneous Squamous Cell Carcinoma in England

A review of terms used to define cutaneous squamous cell carcinoma with a poor prognosis

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer in humans and its incidence is both underestimated and on the rise. cSCC is referred to in the literature as high-risk cSCC, locally advanced cSCC, metastatic cSCC, advanced cSCC, and aggressive cSCC. These terms can give rise to confusion and are not always well defined. In this review, we aim to clarify the concepts underlying these terms with a view to standardizing the description of this tumor, something we believe is necessary in light of the new drugs that have been approved or are in development for cSCC.

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

Invasive cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in the white populations, accounting for 20% of all cutaneous malignancies. Factors implicated in cSCC etiopathogenesis include ultraviolet radiation exposure and chronic photoaging, age, male sex, immunosuppression, smoking and genetic factors. A collaboration of multidisciplinary experts from the European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO) and the European Organisation of Research and Treatment of Cancer (EORTC) was formed to update recommendations on cSCC classification, diagnosis, risk stratification, staging and prevention, based on current literature, staging systems and expert consensus. Common cSCCs are typically indolent tumors, and most have a good prognosis with 5-year cure rates of greater than 90%, and a low rate of metastases (<4%). Further risk stratification into low-risk or high-risk common primary cSCC is recommended based on proposed high-risk factors. Advanced cSCC is classified as locally advanced (lacSCC), and metastatic (mcSCC) including locoregional metastatic or distant metastatic cSCC. Current systems used for staging include the American Joint Committee on Cancer (AJCC) 8th edition, the Union for International Cancer Control (UICC) 8th edition, and Brigham and Women's Hospital (BWH) system. Physical examination for all cSCCs should include total body skin examination and clinical palpation of lymph nodes, especially of the draining basins. Radiologic imaging such as ultrasound of the regional lymph nodes, magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography-computed tomography (PET-CT) scans are recommended for staging of high-risk cSCC. Sentinel lymph node biopsy is currently not recommended. Nicotinamide, oral retinoids, and topical 5-FU have been used for the chemoprevention of subsequent cSCCs in high-risk patients but are not routinely recommended. Education about sun protection measures including reducing sun exposure, use of protective clothing, regular use of sunscreens and avoidance of artificial tanning, is recommended.

Systemic treatment of patients with advanced cutaneous squamous cell carcinoma: response rates and outcomes of the regimes used

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is the second most common type of skin cancer. Few patients with cSCC experience metastases, but the prognosis of advanced cSCC (acSCC) is dismal. Evidence regarding systemic therapy for acSCC is limited. Therefore, we aimed to determine the most effective systemic treatment for acSCC.

PATIENTS AND METHODS

This retrospective study involved 16 Japanese institutions. We documented patient and tumour characteristics and disease course of patients with acSCC who received systemic therapy between 1st January 2006 and 31st December 2015. We compared the overall survival (OS) and progression-free survival (PFS) for (1) platinum versus non-platinum groups, (2) radiation plus chemotherapy first-line therapy (RCT) versus non-RCT groups and (3) platinum-based RCT versus non-platinum-based RCT groups.

RESULTS

Although the use of platinum-based systemic therapy was not associated with statistically significant improvements in PFS and OS, there were significant differences between the RCT and non-RCT groups (PFS: p < 0.001, OS: p = 0.003). In the subgroup analysis, RCT significantly prolonged PFS and OS in the nodal SCC (nSCC) group. For the RCT and non-RCT groups, the median OS was 110 and 14 months, respectively, and the 5-year OS rate was 54% and 21%, respectively.

CONCLUSION

RCT could improve OS in patients with nSCC. However, further multicenter prospective studies are needed to establish evidence for superiority of RCT.

Evolving Role of Systemic Therapies in Non-melanoma Skin Cancer

Keratinocyte cancers - basal and cutaneous squamous cell carcinoma (BCC, cSCC) - are the most common forms of non-melanoma skin cancer (NMSC) and there has been a significant increase in their incidence globally in recent decades. Although the majority of BCC and cSCC are cured with conventional surgery or radiotherapy, certain tumour or patient-determined factors may result in these modalities being inadequate or inappropriate, for example, locally advanced or metastatic disease, high tumour multiplicity, patient comorbidities and patient preferences. In these clinical circumstances, systemic treatment may be indicated, and over the past 10 years a number of new systemic agents have been approved. Nonetheless, effective systemic therapy for keratinocyte cancers remains an area of significant unmet clinical need. Improved understanding of the molecular and immune pathogenesis underlying tumour growth and development is critical for driving future advances and is a research priority. The aim of this review is to provide clinicians with an overview of systemic treatments for BCC and cSCC and will focus on current evidence for conventional chemotherapy, targeted therapies, immunotherapy, adjuvant and neoadjuvant therapy, chemoprevention and future prospects for novel systemic treatment approaches.

Epidemiology of basal and cutaneous squamous cell carcinoma in the U.K. 2013-15: a cohort study

BACKGROUND

Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), together known as keratinocyte cancers (KCs), are the commonest cancer in white ethnic populations. Recent improvements to registry data collection in England has allowed more accurate analysis of the epidemiology of BCC and cSCC and for the first time we are able to provide an accurate (representative) tumour burden for KC in the U.K.

OBJECTIVES

To estimate the incidence of BCC and cSCC in the U.K.

METHODS

A cohort of patients with KCs between 2013 and 2015 were identified using linkage to diagnostic codes derived from pathology reports collected into the national cancer registry. Data from England's cancer registry were combined with data from Scotland, Northern Ireland and Wales. European age-standardized incidence rates (EASRs) of the first BCC and cSCC per patient per annum (PPPA) were calculated.

RESULTS

In the U.K, the EASR of the first BCC and cSCC PPPA in 2013-15 were 285 and 77 per 100 000 person years, respectively (211 120 KCs total in 2015). The mean annual percentage increase was 5% between 2013 and 2015 for both BCC and cSCC. By counting the first KC PPPA, we include an additional 51% KCs compared with the previous reporting technique which counts only the first BCC and cSCC in a patient's lifetime, yet it represents a probable underestimation of 5-11% of the true tumour count.

CONCLUSIONS

Based on an improved methodology, a more representative incidence of KC is presented, which is essential to healthcare planning and will lead to improved understanding of the epidemiology of KC. What's already known about this topic? Keratinocyte cancers (KCs) are the most common cancers affecting white ethnic populations. The incidence of basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC) is increasing worldwide including the U.K., most commonly in elderly male Caucasian patients. These cancers are traditionally substantially underreported and frequently excluded from national cancer statistics. What does this study add? Using improved data collection methods in England and validated tumour-reporting techniques, we report the most accurate BCC and cSCC incidence data for the U.K. ever published. Identifying the first BCC and cSCC per patient per annum, the incidence of BCC and cSCC in the U.K. (excluding Wales) was 285 and 77 per 100 000 person years, respectively, between 2013 and 2015, with more than 210 000 KCs in the U.K. in 2015.

Current Role of Radiotherapy in Non-melanoma Skin Cancer

Non-melanoma skin cancer (NMSC) represents the most frequently diagnosed malignancy worldwide, most being cutaneous basal cell and squamous cell carcinoma. The global incidence of NMSC continues to increase as the global population ages. Numerous treatment options are available for NMSC patients, with radiotherapy an efficacious and tissue-preserving non-surgical option. External beam radiotherapy and brachytherapy are modalities with specific indications and advantages in treating NMSC. Where excision is not an option (medically/technically inoperable) or considered less ideal (e.g. cosmetic or functional outcome), radiotherapy offers an excellent alternative. Inoperable elderly and/or co-morbid patients of poor performance status can benefit from short-course hypofractionated radiotherapy, with very acceptable toxicity. Adjuvant radiotherapy in patients with unfavourable pathology can decrease the risk of local and regional recurrence and associated morbidity and mortality. Radiotherapy has advantages and disadvantages and it is important for clinicians to understand these. Managing patients with NMSC is carried out by clinicians from multiple disciplines but it is imperative that they are all aware of the role of radiotherapy in their patients in various clinical settings. Here we aim to discuss the role and indications for recommending radiotherapy in patients with NMSC.

Complement System in Cutaneous Squamous Cell Carcinoma

Epidermal keratinocyte-derived cutaneous squamous cell carcinoma (cSCC) is the most common metastatic skin cancer with high mortality rates in the advanced stage. Chronic inflammation is a recognized risk factor for cSCC progression and the complement system, as a part of innate immunity, belongs to the microenvironment of tumors. The complement system is a double-edged sword in cancer, since complement activation is involved in anti-tumor cytotoxicity and immune responses, but it also promotes cancer progression directly and indirectly. Recently, the role of several complement components and inhibitors in the regulation of progression of cSCC has been shown. In this review, we will discuss the role of complement system components and inhibitors as biomarkers and potential new targets for therapeutic intervention in cSCC.

A Unique Panel of Patient-Derived Cutaneous Squamous Cell Carcinoma Cell Lines Provides a Preclinical Pathway for Therapeutic Testing

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) incidence continues to rise with increasing morbidity and mortality, with limited treatment options for advanced disease. Future improvements in targeted therapy will rely on advances in genomic/transcriptomic understanding and the use of model systems for basic research. We describe here the panel of 16 primary and metastatic cSCC cell lines developed and characterised over the past three decades in our laboratory in order to provide such a resource for future preclinical research and drug screening.

METHODS

Primary keratinocytes were isolated from cSCC tumours and metastases, and cell lines were established. These were characterised using short tandem repeat (STR) profiling and genotyped by whole exome sequencing. Multiple in vitro assays were performed to document their morphology, growth characteristics, migration and invasion characteristics, and in vivo xenograft growth.

RESULTS

STR profiles of the cSCC lines allow the confirmation of their unique identity. Phylogenetic trees derived from exome sequence analysis of the matched primary and metastatic lines provide insight into the genetic basis of disease progression. The results of in vivo and in vitro analyses allow researchers to select suitable cell lines for specific experimentation.

CONCLUSIONS

There are few well-characterised cSCC lines available for widespread preclinical experimentation and drug screening. The described cSCC cell line panel provides a critical tool for in vitro and in vivo experimentation.