Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a rare neuroendocrine carcinoma. The cellular origin of MCC may include Merkel cell precursors. The incidence of MCC has increased significantly however trends may have been confounded by evolving diagnostic criteria. The two key aetiologies of MCC are ultraviolet radiation and Merkel cell polyoma virus (MCPyV). Both have unique mechanisms of carcinogenesis. MCC presents non-specifically as a rapidly growing, red-to-violet nodule on sun-exposed areas. Diagnostic accuracy has improved through immunohistochemical markers such as CK-20. Lymph nodes should be evaluated in MCC through examination and sentinel biopsy. USS, CT, MRI and CT-PET may be useful in staging. Management depends on tumour location, stage and comorbidities. MCPyV status may guide treatment strategy in the future. Treatment for the primary MCC is commonly wide local excision followed by radiotherapy, guided by anatomical constraints. There is uncertainty about surgical margins. Treatments for nodal disease have not been determined through trials. They include nodal dissection or radiotherapy for clinically or radiologically apparent disease, and adjuvant nodal irradiation for negative nodes, microscopic disease or following nodal dissection for definite disease. Patients with loco-regional advanced inoperable disease should be considered for combination therapy including chemotherapy, radiotherapy, surgery and immunotherapy. Systemic therapy for advanced disease includes immune checkpoint inhibitors targeting the PD-1/PD-L1 pathway. Avelumab can improve survival in metastatic MCC. Immunotherapy may result in longer disease control. Various other immunotherapeutic and molecular agents are undergoing trials. MCC continues to have a high mortality characterized by high recurrence and early metastases.

An updated report on the incidence and epidemiological trends of keratinocyte cancers in the United Kingdom 2013-2018.

Introduction: The most common cancers in the UK are keratinocyte cancers (KCs): the combined term for basal cell carcinomas (BCCs) and cutaneous squamous cell carcinomas (cSCCs). Registration of KC is challenging due to high numbers and multiplicity of tumours per person. Methods: We provide an updated report on the descriptive epidemiology of trends in KC incidence for the resident populations of UK countries (England, Northern Ireland, Scotland and Wales) using population-based cancer registry and pathology report data, 2013-18. Results: Substantial increases in cSCC incidence in England, Scotland and Northern Ireland can be detected for the period of 2013-18, and the incidence of cSCC also increased in Wales from 2016 to 2018. In contrast, however, the pattern of annual change in the incidence of BCC across the nations differs. In England, the incidence of BCC declined slightly from 2016 to 2018, however, the overall trend across 2013-18 is not statistically significant. In Scotland, the incidence of BCC shows some variability, declining in 2017 before increasing in 2018, and the overall trend across 2013-18 was also not statistically significant. In Northern Ireland, the incidence of BCC increased significantly over the study period, and in Wales, the incidence of BCC increased from 2016 to 2018. One in five people will develop non-melanoma skin cancers (NMSC) in their lifetime in England. This estimate is much higher than the lifetime risk of melanoma (1 in 36 males and 1 in 47 females born after 1960 in the UK), which further highlights the burden of the disease and importance of early prevention strategies. Conclusions: We highlight how common these tumours are by publishing the first ever lifetime incidence of NMSC. Additionally, the first time reporting of the age standardised incidence of KC in Wales further confirms the scale of the disease burden posed by these cancers in the UK. With approximately one in five people developing NMSC in their lifetime, optimisation of skin cancer prevention, management and research are essential.

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.

The menstrual cycle and the skin.

Perimenstrual exacerbations of dermatoses are commonly recognized, yet our knowledge of the underlying pathophysiological mechanisms remains imperfect. Research into the effects of oestrogen on the skin has provided evidence to suggest that oestrogen is associated with increases in skin thickness and dermal water content, improved barrier function, and enhanced wound healing. Research into the effects of progesterone suggests that the presence of various dermatoses correlates with peak levels of progesterone. Dermatoses that are exacerbated perimenstrually include acne, psoriasis, atopic eczema and irritant dermatitis, and possibly also erythema multiforme. Exacerbations occur at the peak levels of progesterone in the menstrual cycle. Underlying mechanisms include reduced immune and barrier functions as a result of cyclical fluctuations in oestrogen and/or progesterone. Autoimmune progesterone and oestrogen dermatitis are the best-characterized examples of perimenstrual cutaneous reactions to hormones produced during the menstrual cycle. In this review, we describe the current understanding of the menstrual cycle, and its effect on the skin and cutaneous disorders.