Global epidemiology of actinic keratosis in the general population: a systematic review and meta-analysis.

BACKGROUND: Actinic keratosis (AK) is a common dermatological condition, and among the most common dermatological diagnoses in older populations. Although the prevalence of AK depends on demographic and environmental factors, little is known about the global context of AK. OBJECTIVES: To provide a comprehensive and updated analysis of the global prevalence rate and incidence of AK in the general population through a systematic review and meta-analysis, and - through subgroup analyses - to identify high-risk phenotypes, demographic and lifestyle risk factors and regional variations in disease prevalence. METHODS: A systematic search of Embase, MEDLINE, Web of Science and Google Scholar was performed on 20 May 2022. Two reviewers independently screened and assessed the quality of each study using a validated critical appraisal checklist. Epidemiological measurements (e.g. prevalence) from individual studies performed in the general population were then pooled in a random-effects meta-analysis. Subgroup analyses (i.e. population age, geographical region, occupation, sex and study quality) were conducted. RESULTS: Of the 65 articles that made it through the full-text screening, 60 reported a point prevalence. A meta-analysis of these articles yielded an overall point prevalence of 14% [95% confidence interval (CI) 14-15]. In further analyses, the calculated prevalence rate varied depending on subgroup. The pooled incidence rate from the seven eligible studies analysed was 1928 per 100 000 person-years (PY; 95% CI -439 to 4294). CONCLUSIONS: This comprehensive meta-analysis provides an updated global prevalence rate of AK of 14%, indicating a significant worldwide disease burden. The incidence rate of AK was found to be 1928 per 100 000 PY, emphasizing a growing public health concern. However, high heterogeneity among studies suggests that various factors influence the AK prevalence rate, necessitating further research to understand the observed differences.

Weighted metrics are required when evaluating the performance of prediction models in nested case-control studies.

BACKGROUND: Nested case-control (NCC) designs are efficient for developing and validating prediction models that use expensive or difficult-to-obtain predictors, especially when the outcome is rare. Previous research has focused on how to develop prediction models in this sampling design, but little attention has been given to model validation in this context. We therefore aimed to systematically characterize the key elements for the correct evaluation of the performance of prediction models in NCC data. METHODS: We proposed how to correctly evaluate prediction models in NCC data, by adjusting performance metrics with sampling weights to account for the NCC sampling. We included in this study the C-index, threshold-based metrics, Observed-to-expected events ratio (O/E ratio), calibration slope, and decision curve analysis. We illustrated the proposed metrics with a validation of the Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA version 5) in data from the population-based Rotterdam study. We compared the metrics obtained in the full cohort with those obtained in NCC datasets sampled from the Rotterdam study, with and without a matched design. RESULTS: Performance metrics without weight adjustment were biased: the unweighted C-index in NCC datasets was 0.61 (0.58-0.63) for the unmatched design, while the C-index in the full cohort and the weighted C-index in the NCC datasets were similar: 0.65 (0.62-0.69) and 0.65 (0.61-0.69), respectively. The unweighted O/E ratio was 18.38 (17.67-19.06) in the NCC datasets, while it was 1.69 (1.42-1.93) in the full cohort and its weighted version in the NCC datasets was 1.68 (1.53-1.84). Similarly, weighted adjustments of threshold-based metrics and net benefit for decision curves were unbiased estimates of the corresponding metrics in the full cohort, while the corresponding unweighted metrics were biased. In the matched design, the bias of the unweighted metrics was larger, but it could also be compensated by the weight adjustment. CONCLUSIONS: Nested case-control studies are an efficient solution for evaluating the performance of prediction models that use expensive or difficult-to-obtain biomarkers, especially when the outcome is rare, but the performance metrics need to be adjusted to the sampling procedure.

Cumulative incidence and timing of subsequent cutaneous squamous cell carcinomas stratified for patients with organ transplantation and hematologic malignancies: A nationwide cohort study.

BACKGROUND: There is lack of nationwide data on the cumulative incidence and timing of subsequent cutaneous squamous cell carcinomas (cSCCs) among patients with a first cSCC. OBJECTIVE: To investigate the cumulative incidence and timing of subsequent cSCCs. METHODS: Patients with a first cSCC in 2007/2008 from the Netherlands Cancer Registry were linked to the Netherlands Pathology Registry for subsequent cSCCs and the Netherlands Organ Transplant Registry. Cumulative incidence function curves were calculated for subsequent cSCCs and stratified for immune status. RESULTS: Among the 12,345 patients, second to sixth cSCC occurred in 4325, 2010, 1138, 739, and 501 patients, with median time intervals of 1.4, 1.2, 0.9, 0.6, and 0.5 years after the previous cSCC, respectively. The cumulative incidence of a subsequent cSCC at 5 years increased from 28% to 67% for the second to sixth cSCC. For solid organ transplant recipients, the cumulative incidences increased from 74% to 92% and from 41% to 64% for patients with hematologic malignancy. LIMITATIONS: Only histopathologically confirmed cSCCs were included. CONCLUSION: The risk of a subsequent cSCC steeply rises with the number of prior cSCCs and immune status, while the time interval decreases. This can support more informed decisions about follow-up management.

Trends in incidence, treatment and survival of Merkel cell carcinoma in England 2004-2018: a cohort study.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare tumour with neuroendocrine differentiation and high associated mortality. Studies that describe the epidemiology of MCC are often limited by small sample size, short duration of follow-up, absence of nationwide data and paucity of data on different risk factors. OBJECTIVES: To determine the incidence, demographics and survival for MCC in England between 2004 and 2018. METHODS: This national retrospective cohort study identified all cases of MCC in England from 2004 to 2018 using national population-based data from the National Disease Registration Service. Crude counts, European age-standardized incidence rates (EASRs) and joinpoint analysis were conducted. Patient demographics and treatments received were described. Multivariable Cox regression analysis was used to study risk factors for MCC-specific mortality, by including a priori defined demographic factors, tumour characteristics and immunosuppression. Treatment data were not included in the Cox regression analysis. RESULTS: A total of 3775 MCC tumours were registered. The median age at diagnosis was 81 years (interquartile range 74-87). Overall, 96·6% of patients identified as White ethnicity, and 8·3% of patients were immunosuppressed. The most common site was the face (27·4%). Patients most often presented with stage one disease (22·8%); however, stage was unknown in 31·0%. In total, 80·7% of patients underwent surgical excision, 43·5% radiotherapy and 9·2% systemic therapy. The EASR increased from 0·43 per 100 000 person-years (PYs) to 0·65 per 100 000 person-years between 2004 and 2018, representing a significant annual percentage change of 3·9%. The EASR was greater in men than in women for all years, with an overall male-to-female ratio of 1·41 : 1. The highest EASR was in South West England. Five-year disease-specific survival was 65·6% [95% confidence interval (CI) 63·8-67·4], with a median follow-up of 767 days. MCC-specific mortality increased with age [hazard ratio (HR) 1·02, 95% CI 1·02-1·03], deprivation (HR 1·43, 95% CI 1·16-1·76), immunosuppression (HR 2·80, 95% CI 2·34-3·34) and stage at diagnosis (HR 8·24, 95% CI 5·84-11·6). CONCLUSIONS: This study presents the largest national MCC dataset in Europe, and the most complete reporting of MCC incidence and survival ever published. With the EASR of MCC increasing and high associated mortality, this study encourages further research into the pathology, diagnosis and therapeutic options for MCC to support management guidelines.

Sebaceous carcinoma epidemiology, associated malignancies and Lynch/Muir-Torre syndrome screening in England from 2008 to 2018.

BACKGROUND: Sebaceous carcinomas (SC) may be associated with the cancer predisposition syndrome Muir-Torre/Lynch syndrome (MTS/LS), identifiable by SC mismatch repair (MMR) screening; however, there is limited data on MMR status of SC. OBJECTIVE: To describe the epidemiology of SC, copresentation of other cancers, and population level frequency of MMR screening in SC. METHODS: A population-based retrospective cohort study of SC patients in the National Cancer Registration and Analysis Service in England. RESULTS: This study included 1077 SC cases (739 extraocular, 338 periocular). Age-standardized incidence rates (ASIR) were higher in men compared with women, 2.74 (95% CI, 2.52-9.69) per 1,000,000 person-years for men versus 1.47 person-years (95% CI, 1.4-1.62) for women. Of the patients, 19% (210/1077) developed at least one MTS/LS-associated malignancy. MMR immunohistochemical screening was performed in only 20% (220/1077) of SC tumors; of these, 32% (70/219) of tumors were MMR deficient. LIMITATIONS: Retrospective design. CONCLUSIONS: Incorporation of MMR screening into clinical practice guidelines for the management of SC will increase the opportunity for MTS/LS diagnoses, with implications for cancer surveillance, chemoprevention with aspirin, and immunotherapy treatment targeted to MTS/LS cancers.

The association between atopic eczema and lymphopenia: Results from a UK cohort study with replication in US survey data.

BACKGROUND: Lymphocyte skin homing in atopic eczema (AE) may induce lymphopenia. OBJECTIVE: To determine if AE is associated with lymphopenia. METHODS: We used UK primary care electronic health records (Clinical Practice Research Datalink GOLD) for a matched cohort study in adults (18 years+) (1997-2015) with at least one recorded lymphocyte count. We matched people with AE to up to five people without. We used multivariable logistic regression to estimate the association between AE and lymphopenia (two low lymphocyte counts within 3 months) and linear mixed effects regression to estimate the association with absolute lymphocyte counts using all available counts. Cox proportional hazard models were used to investigate the effect of lymphopenia on common infections. We replicated the study using US survey data (National Health and Nutrition Examination Survey [NHANES]). RESULTS: Among 71,731 adults with AE and 126,349 adults without AE, we found an adjusted odds ratio (OR) for lymphopenia of 1.16 (95% CI: 1.09-1.23); the strength of association increased with increasing eczema severity. When comparing all recorded lymphocyte counts from adults with AE (n = 1,497,306) to those of people without AE (n = 4,035,870) we saw a lower mean lymphocyte (adjusted mean difference -0.047 × 109 /L [95% CI: -0.051 to -0.043]) in those with AE. The difference was larger for men, with increasing age, and with increasing AE severity and was present among people with AE not treated with immunosuppressive drugs. In NHANES (n = 22,624), the adjusted OR for lymphopenia in adults with AE was 1.30 (95% CI: 0.80-2.11), and the adjusted mean lymphocyte count difference was -0.03 × 109 /L (95% CI: -0.07 to 0.02). Despite having a lower lymphocyte count, adjusting for time with lymphopenia, did not alter risk estimates of infections. CONCLUSION: Atopic eczema, including increasing AE severity, is associated with a decreased lymphocyte count, regardless of immunosuppressive drug use. Whether the lower lymphocyte count has wider health implications for people with severe eczema warrants further investigation.

Genetic Concordance in Primary Cutaneous Melanoma and Matched Metastasis: A Systematic Review and Meta-Analysis.

Studying primary melanoma and its corresponding metastasis has twofold benefits. Firstly, to better understand tumor biology, and secondly, to determine which sample should be examined in assessing drug targets. This study systematically analyzed all the literature on primary melanoma and its matched metastasis. Following PRISMA guidelines, we searched multiple medical databases for relevant publications from January 2000 to December 2022, assessed the quality of the primary-level studies using the QUIPS tool, and summarized the concordance rate of the most reported genes using the random-effects model. Finally, we evaluated the inter-study heterogeneity using the subgroup analysis. Thirty-one studies investigated the concordance of BRAF and NRAS in 1220 and 629 patients, respectively. The pooled concordance rate was 89.4% [95% CI: 84.5; 93.5] for BRAF and 97.8% [95% CI: 95.8; 99.4] for NRAS. When high-quality studies were considered, only BRAF mutation status consistency increased. Five studies reported the concordance status of c-KIT (93%, 44 patients) and TERT promoter (64%, 53 patients). Lastly, three studies analyzed the concordance of cancer genes involved in the signaling pathways, apoptosis, and proliferation, such as CDKN2A (25%, four patients), TP53 (44%, nine patients), and PIK3CA (20%, five patients). Our study found that the concordance of known drug targets (mainly BRAF) during melanoma progression is higher than in previous meta-analyses, likely due to advances in molecular techniques. Furthermore, significant heterogeneity exists in the genes involved in the melanoma genetic makeup; although our results are based on small patient samples, more research is necessary for validation.

Limited impact of COVID-19-related diagnostic delay on cutaneous melanoma and squamous cell carcinoma tumour characteristics: a nationwide pathology registry analysis.

BACKGROUND: The COVID-19 pandemic reduced the number of skin cancer diagnoses, potentially causing a progression to unfavourable tumour stages. OBJECTIVES: To identify the impact of delayed diagnostics on primary invasive melanoma and cutaneous squamous cell carcinoma (cSCC) by comparing tumour (pT) stage, Breslow thickness and invasion depth from before to after the first and second lockdown periods. METHODS: In this population-based cohort study, histopathology reports registered between 1 January 2018 and 22 July 2021 were obtained from the nationwide histopathology registry in the Netherlands. The Breslow thickness of melanomas, invasion depth of cSCCs, and pT stage for both tumour types were compared across five time periods: (i) pre-COVID, (ii) first lockdown, (iii) between first and second lockdowns, (iv) second lockdown and (v) after second lockdown. Breslow thickness was compared using an independent t-test. pT-stage groups were compared using a χ2 -test. Outcomes were corrected for multiple testing using the false discovery rate. RESULTS: In total, 20 434 primary invasive melanomas and 68 832 cSCCs were included in this study. The mean primary melanoma Breslow thickness of the prepandemic era (period i) and the following time periods (ii-v) showed no significant difference. A small shift was found towards unfavourable pT stages during the first lockdown compared with the pre-COVID period: pT1 52·3% vs. 58·6%, pT2 18·9% vs. 17·8%, pT3 13·2% vs. 11·0%, pT4 9·1% vs. 7·3% (P = 0·001). No relevant changes were seen in subsequent periods. No significant change in pT stage distribution was observed between the pre-COVID (i) and COVID-affected periods (ii-v) for cSCCs. CONCLUSIONS: To date, the diagnostic delay caused by COVID-19 has not resulted in relatively more unfavourable primary tumour characteristics of melanoma or cSCC. Follow-up studies in the coming years are needed to identify a potential impact on staging distribution and survival in the long term.

Validation of four cutaneous squamous cell carcinoma staging systems using nationwide data.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer worldwide with relatively low metastatic potential (2-5%). Developments in therapeutic options have highlighted the need to better identify high-risk patients who could benefit from closer surveillance, adjuvant therapies and baseline/follow-up imaging, while at the same time safely omitting low-risk patients from further follow-up. Controversy remains regarding the predictive performance of current cSCC staging systems and which methodology to adopt. OBJECTIVES: To validate the performance of four cSCC staging systems [American Joint Committee on Cancer 8th edition (AJCC8), Brigham and Women's Hospital (BWH), Tübingen and Salamanca T3 refinement] in predicting metastasis using a nationwide cohort. METHODS: A nested case-control study using data from the National Disease Registration Service, England, 2013-2015 was conducted. Metastatic cSCC cases were identified using an algorithm to identify all potential cases for manual review. These were 1 : 1 matched on follow-up time to nonmetastatic controls randomly selected from 2013. Staging systems were analysed for distinctiveness, homogeneity, monotonicity, specificity, positive predictive value (PPV), negative predictive value (NPV) and c-index. RESULTS: We included 887 metastatic cSCC cases and 887 nonmetastatic cSCC controls. The BWH system showed the highest specificity [92.8%, 95% confidence interval (CI) 90.8-94.3%, PPV (13.2%, 95% CI 10.6-16.2) and c-index (0.84, 95% CI 0.82-0.86). The AJCC8 showed superior NPV (99.2%, 95% CI 99.2-99.3), homogeneity and monotonicity compared with the BWH and Tübingen diameter and thickness classifications (P < 0.001). Salamanca refinement did not show any improvement in AJCC8 T3 cSCC staging. CONCLUSIONS: We validated four cSCC staging systems using the largest nationwide dataset of metastatic cSCC so far. Although the BWH system showed the highest overall discriminative ability, PPV was low for all staging systems, which shows the need for further improvement and refining of current cSCC staging systems.

Cumulative incidence and disease-specific survival of metastatic cutaneous squamous cell carcinoma: A nationwide cancer registry study.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) represents the most serious form of keratinocyte cancers because of its metastatic potential. Studies on nationwide incidence and disease-specific survival rates of metastatic cSCC (mcSCC) are lacking. OBJECTIVE: To investigate the cumulative incidence and disease-specific survival of patients with mcSCC in the Dutch population and assess patient-based risk factors. METHODS: We conducted a nationwide cancer registry study including all patients with the first cSCC in 2007 or 2008, using data from the Netherlands Cancer Registry, the nationwide network and registry of histopathology and cytopathology, and Statistics Netherlands. Cumulative incidence and Kaplan-Meier curves were calculated, and time-dependent Cox proportional hazards regression analyses were used. RESULTS: Of the 11,137 patients, metastases developed in 1.9% (n = 217). The median time to metastasis was 1.5 years (interquartile range 0.6-3.8 years). The risk factors were age (adjusted hazard ratio [aHR] 1.03, 95% CI 1.02-1.05), male sex (aHR 1.7, 95% CI 1.3-2.3), and immunosuppression (aHR [organ transplant recipient] 5.0, 95% CI 2.5-10.0; aHR [hematologic malignancy] 2.7, 95% CI 1.6-4.6). The 5-year disease-specific survival for patients with mcSCC was 79.1%. LIMITATIONS: Only histopathologically confirmed mcSCCs were included. CONCLUSION: About 2% of cSCCs metastasize, with higher risk for men, increasing age, and immunocompromised patients. Disease-specific survival for patients with mcSCC is high.

Risk factors for metastatic cutaneous squamous cell carcinoma: Refinement and replication based on 2 nationwide nested case-control studies.

BACKGROUND: Risk factors for cutaneous squamous cell carcinoma (cSCC) metastasis have been investigated only in relatively small data sets. OBJECTIVE: To analyze and replicate risk factors for metastatic cSCC. METHODS: From English and Dutch nationwide cancer registry cohorts, metastatic cases were selected and 1:1 matched to controls. The variables were extracted from pathology reports from the National Disease Registration Service in England. In the Netherlands, histopathologic slides from the Dutch Pathology Registry were revised by a dermatopathologist. Model building was performed in the English data set using backward conditional logistic regression, whereas replication was performed using the Dutch data set. RESULTS: In addition to diameter and thickness, the following variables were significant risk factors for metastatic cSCC in the English data set (n = 1774): poor differentiation (odds ratio [OR], 4.56; 95% CI, 2.99-6.94), invasion in (OR, 1.69; 95% CI, 1.05-2.71)/beyond (OR, 4.43; 95% CI, 1.98-9.90) subcutaneous fat, male sex (OR, 2.59; 95% CI, 1.70-3.96), perineural/lymphovascular invasion (OR, 2.12; 95% CI, 1.21-3.71), and facial localization (OR, 1.57; 95% CI, 1.02-2.41). Diameter and thickness showed significant nonlinear relationships with metastasis. Similar ORs were observed in the Dutch data set (n = 434 cSCCs). LIMITATIONS: Retrospective use of pathology reports in the English data set. CONCLUSION: cSCC staging systems can be improved by including differentiation, clinical characteristics such as sex and tumor location, and nonlinear relationships for diameter and thickness.

Association between antihypertensive medications and risk of skin cancer in people older than 65 years: a population-based study.

BACKGROUND: The risk of skin cancer associated with antihypertensive medication use is unclear, although thiazides have been implicated in regulatory safety warnings. We aimed to assess whether use of thiazides and other antihypertensives is associated with increased rates of keratinocyte carcinoma and melanoma. METHODS: We conducted a population-based inception cohort study using linked administrative health data from Ontario, 1998-2017. We matched adults aged ≥ 66 years with a first prescription for an antihypertensive medication (thiazides, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, ß-blockers) by age and sex to 2 unexposed adults who were prescribed a non-antihypertensive medication within 30 days of the index date. We evaluated each antihypertensive class in a separate cohort study. Our primary exposure was the cumulative dose within each class, standardized according to the World Health Organization's Defined Daily Dose. Outcomes were time to first keratinocyte carcinoma, advanced keratinocyte carcinoma and melanoma. RESULTS: The inception cohorts included a total of 302 634 adults prescribed an antihypertensive medication and 605 268 unexposed adults. Increasing thiazide exposure was associated with an increased rate of incident keratinocyte carcinoma (adjusted hazard ratios [HRs] per 1 Defined Annual Dose unit 1.08, 95% confidence interval [CI] 1.03-1.14), advanced keratinocyte carcinoma (adjusted HR 1.07, 95% CI 0.93-1.23) and melanoma (adjusted HR 1.34, 95% CI 1.01-1.78). We found no consistent evidence of association between other antihypertensive classes and keratinocyte carcinoma or melanoma. INTERPRETATION: Higher cumulative exposure to thiazides was associated with increased rates of incident skin cancer in people aged 66 years and older. Consideration of other antihypertensive treatments in patients at high risk of skin cancer may be warranted.

Practice Variation in Skin Cancer Treatment and Follow-Up Care: A Dutch Claims Database Analysis.

BACKGROUND: Quality indicators are used to benchmark and subsequently improve quality of healthcare. However, defining good quality indicators and applying them to high-volume care such as skin cancer is not always feasible. OBJECTIVES: To determine whether claims data could be used to benchmark high-volume skin cancer care and to assess clinical practice variation. METHODS: All skin cancer care-related claims in dermatology in 2016 were extracted from a nationwide claims database (Vektis) in the Netherlands. RESULTS: For over 220,000 patients, a skin cancer diagnosis-related group was reimbursed in 124 healthcare centres. Conventional excision reflected 75% of treatments for skin cancer but showed large variation between practices. Large practice variation was also found for 5-fluorouracil and imiquimod creams. The practice variation of Mohs micrographic surgery and photodynamic therapy was low under the 75th percentile, but outliers at the 100th percentile were detected, which indicates that few centres performed these therapies far more often than average. On average, patients received 1.8 follow-up visits in 2016. CONCLUSIONS: Claims data demonstrated large practice variation in treatments and follow-up visits of skin cancer and may be a valid and feasible data set to extract quality indicators. The next step is to investigate whether detected practice variation is unwarranted and if a reduction improves quality and efficiency of care.

Choice of Systemic Drugs for the Management of Moderate-to-severe Psoriasis: A Cross-country Comparison Based on National Health Insurance Data.

Current management of moderate-to-severe psoriasis may be heterogeneous between European countries, probably due to differences in the organization of care. The aim of this study was to compare the utilization of systemic treatments for psoriasis between 2 coun-tries. All adults with psoriasis who were registered in the French (SNDS) and the Dutch (VEKTIS) national health insurance databases between 2012 and 2016 were eligible for inclusion. In France, 105,035 (15%) of 684,156 patients and, in the Netherlands, 37,405 (28.6%) of 130,822 patients received at least a systemic agent. In France, the proportion of patients treated with systemic agents was constant, while the type of drugs dispensed shifted from non-biological to biological agents. In the Netherlands, the first systemic treatment was methotrexate and, in France, acitretin. In France, the choice of the first biologic was much more variable than it was in the Netherlands, where a large proportion of patients were dispensed ustekinumab. This study highlights discrepancies between France and the Netherlands concerning the choice of first non-biologic agent and first biologic agent for patients with psoriasis. These discrepancies may be due to differences in the healthcare systems between the 2 countries.

Melanoma in older patients: declining gap in survival between younger and older patients with melanoma.

Background: Older people have the highest incidence of melanoma and the population in most Western countries is ageing. We evaluated how the gap in incidence and survival between younger and older patients has developed during the past decades.Material and methods: All patients diagnosed with cutaneous melanoma between 1989 and 2015 (n = 84,827) were identified from the Netherlands Cancer Registry. Elderly were defined as aged ≥70 years. Differences in patient and tumor characteristics were described, age-specific incidence rates were calculated, and relative survival (RS) and multivariable analyses estimating the Relative Excess Rate of dying (RER) were conductedResults: In older men, the melanoma age-standardized incidence increased from 18 to 103/100,000 person-years (py) between 1989 and 2015 and in older women from 23 to 70/100,000 py. In younger men and women, it increased from 8 to 21 and from 13 to 28/100,000 py, respectively. Median Breslow thickness declined from 1.8 to 1.1 mm and from 1.6 to 1.1 mm in older men and women (2003 versus 2015), and from 1.1 to 0.9 mm and 0.9 to 0.8 mm in younger men and women. In older men, 5-year RS increased from 67% (95% CI: 63%-72%) in 1989-1997 to 85% (95% CI: 83%-87%) in 2007-2015 and in older women from 81% (95% CI: 78%-85%) to 89% (95% CI: 87%-91%). In younger men and women, RS increased from 82% (95% CI: 81%-83%) to 90% (95% CI: 90%-91%) and from 92% (95% CI: 92%-93%) to 96% (95% CI: 95%-96%). After case-mix correction , older men and women no longer showed an improved survival over time (RER 2010-2015 versus 2003-2009: 0.97; 95% CI: 0.81-1.16 and 0.95; 95% CI: 0.79-1.16). Whereas in younger men and women survival remained improved (RER 0.75; 95% CI: 0.67-0.83 and 0.77; 95%CI: 0.67-0.89).Conclusion: The gap in melanoma incidence between younger and older people is increasing due to a strong increase in incidence in older adults. Disparities in survival are declining, related to a narrowing gap in Breslow thickness.

Increasing Costs of Skin Cancer due to Increasing Incidence and Introduction of Pharmaceuticals, 2007-2017.

Skin cancer is the most common type of cancer and its incidence is increasing. The objective of this study was to describe the trends in reimbursed drug and hospital costs of benign and (pre)malignant skin tumours, and to present future projections. Therefore, nationwide hospital and drug reimbursement data (for the period 2007-17) were used. In 2017, malignant skin tumours were the 4th most costly cancer in the Netherlands (after breast, colorectal, and lung cancer). The total costs for skin tumours increased from €278 million for 384,390 patients (in 2007) to €465 million for 578,355 patients (in 2017). Drug costs increased from €0.7 million to €121 million (over the period 2007-17), resulting in a 26% share of overall costs in 2017. Future costs are projected to reach €1.35 billion in 2030. In conclusion, the increasing costs of skin cancer are strongly affected by the increasing incidence and introduction of expensive drugs, and future projections are for an alarming increase.

Validation of the English Basal and Squamous Cell Carcinoma Quality of Life (BaSQoL) Questionnaire.

BACKGROUND: Keratinocyte carcinomas (KC) impact patient quality of life (QoL). There is a need for validated QoL instruments specific to KC. The Basal and Squamous Cell Carcinoma QoL (BaSQoL) questionnaire was developed to comprehensively measure issues of importance to patients with KC. OBJECTIVE: To validate and characterize the BaSQoL questionnaire for QoL measurement after diagnosis and treatment of KC. METHODS: This was a prospective, observational study. Patients with basal cell carcinoma (BCC) or squamous cell carcinoma (SCC) were asked to fill out BaSQoL, Skin Cancer Index (SCI), and Hospital Anxiety and Depression Scale (HADS) questionnaires. Descriptive statistics and classical test theory were used to assess validity. RESULTS: One hundred eighty-seven subjects enrolled in this study: 122 with BCC and 65 with SCC. One hundred seventy-one subjects (91.4%) completed questionnaires at all 3 time points; 16 patients (8.6%) were lost to follow-up. Overall performance using classical test theory was good, with good internal consistency (Cronbach's α 0.63-0.80). BaSQoL subscales were strongly correlated with subscales of the SCI, demonstrating convergent validity, and weakly correlated with HADS, showing divergent validity. CONCLUSION: The English language version of BaSQoL has good face, content, and construct validity. This study validates BaSQoL for use in English-speaking patients with BCC and SCC.

Commonly Used Endovenous Laser Ablation (EVLA) Parameters Do Not Influence Efficacy: Results of a Systematic Review and Meta-Analysis.

OBJECTIVES: The objective of this systematic review and meta-analysis was to summarise available randomised controlled trials (RCTs) of EVLA efficacy, and to define the differences in success rate of variations in wavelength, administered energy, outcome definition, and follow up period. METHODS: A literature search was conducted in Embase, Medline (Ovid-SP), Cochrane Central Database, and Web of Science from inception to November 2017. RCTs with follow up of more than three months were included. The studied outcome was the proportion of patients with EVLA treatment success, defined as absence of reflux or occlusion of the great saphenous vein (GSV). Pooled proportions of anatomical success were compared. Subgroup and meta-regression analysis included wavelengths (short [810, 940, and 980 nm], long [1470, 1500, and 1920 nm]), amount of energy (≤50 J/cm, > 50 J/cm), follow up (≤1 year, > 1 year), outcome definition (occlusion, no reflux), and quality of the studies (low risk of bias, unclear/high risk of bias). RESULTS: Twenty-eight RCTs, with a total of 2829 GSVs were included. The overall success rate of EVLA was 92% (95% CI 90-94%, I2 = 68%). In subgroup analysis, no statistically significant differences were found for long or short wavelengths (95% [95% CI 91-97%] vs. 92% [95% CI 89-94%], p = .15), high or low administered energy (93% [95% CI 89-95%] vs. 92% [95% CI 90-94%], p = .99), long or short follow up (89% [95% CI 84-93%] vs. 93% [95% CI 91-95%], p = .13) and outcome definition (occlusion group 94% [95% CI 91-96%] vs. absence of reflux group 91% [95% CI 87-94%], p = .26). Studies with low risk of bias reported a significantly higher success rate than high or unclear risk of bias (93% [95% CI 90-95%] vs. 89% [95% CI 83-93%], p = .04). CONCLUSIONS: The overall success rate of EVLA is high (92%), even with increasing follow up. Commonly used parameters of EVLA (wavelength, administered energy, and outcome definition) have no influence on the treatment success rate.

Dermatofibrosarcoma Protuberans Re-excision and Recurrence Rates in the Netherlands Between 1989 and 2016.

Dermatofibrosarcoma protuberans is a rare soft tissue tumour with a very low (p < 0.5%) rate of metastasis. Rates of re-excision and recurrence were determined using data from the Netherlands Cancer Registry between 1989 and 2016. Of the 1,890 instances of dermatofibrosarcoma protuberans included, 87% were treated with excision, 4% with Mohs micrographic surgery, and 9% otherwise or unknown. Linked pathology data were retrieved for 1,677 patients. Half of all excisions (847/1,644) were incomplete and 29% (192/622) of all re-excisions were incomplete. The cumulative incidence of a recurrence was 7% (95% confidence interval (95% CI) 6-8) during a median follow-up of 11 years (interquartile range (IQR) 6-17). After Mohs micrographic surgery (n = 34), there were no recurrences during a median follow-up of 4 years (IQR 3-6). Due to the high rate of incomplete excisions and recurrences after excision, this study supports the European guideline, which recommends treating dermatofibrosarcoma protuberans with Mohs micrographic surgery in order to decrease the rate of recurrence.