Darker Skin Types Research Articles

Pigmented basal cell carcinoma

Pigmented basal cell carcinoma (pBCC) is an uncommon clinical and histopathological variant that is more frequent in darker skin types. The increased number of melanocytes and the subsequent melanin production are responsible for the increased pigmentation in this variant. Clinically, pBCC has a polychromatic nature. The most common clinical mimic of this entity is malignant melanoma. This article focuses on providing dermatologists with insights into this condition.

What's New in Diode Laser Hair Removal?

ABSTRACTIntroductionLaser hair removal remains one of the most common procedures in cosmetic dermatology. It has always been challenging because of the higher competing epidermal melanocyte as the targeted hair chromophore is also melanin. As a result, to avoid unwanted side effects from laser therapy while maintaining high efficacy levels, the use of the right laser device, appropriate settings, and customized pre and posttreatment care are crucial. With more efficient versions of existing lasers in the market, the safety profile has been taken care of without compromising the efficacy. Diode lasers along with long pulsed Nd:YAG and alexandrite are considered as the safest hair removal lasers.ObjectiveTo summarize recent developments in diode laser hair reduction focusing on improvements in efficiency, safety, and patient compliance with recent innovations.Materials and MethodsA review of recent literature updates in diode laser hair reduction technology focusing on multiwavelength systems, safety profiles, and innovations in laser device was searched using keywords diode laser hair removal and mutliwavelength diode laser devices.ResultsCurrently, 810 nm diode laser is the most extensively used technology for the long term elimination of unwanted hair, thus establishing itself as an efficacious and safe modality. The rapid multiple pass in motion technique with lesser fluence and gradual heating of the skin epidermis was more well tolerated in patients than the higher fluence single shot method. Most popular combination of triple wavelength was 755, 810, and 1064 nm, which is considered most effective with least complications.ConclusionDiode lasers still remain the gold standard in laser hair removal especially on darker skin types. Recent innovations in diode laser have significantly improved the efficacy, safety, and patient compliance with hair reduction. Multiwavelength platforms seems to be the way forward, however the basic principles and certain problems like minimal pain, treating thin hair, paradoxical hair growth, white hair removal still remains a challenge.

53156 Prevention of post-inflammatory hyperpigmentation in dark skin types after a non-ablative laser

53156 Prevention of post-inflammatory hyperpigmentation in dark skin types after a non-ablative laser

Mechanisms of Selected Cassipourea Metabolites for Melasma Treatment: Network Pharmacology and Molecular Dynamics Study

Background Melasma is a common dyschromia, mainly found in women with darker skin types. Although asymptomatic, melasma significantly impacts patients’ quality of life. Due to this complex pathogenesis, melasma is difficult to treat. Plant and plant-derived products have been explored as alternatives for the treatment of melasma. Methods This study utilized network pharmacology coupled with molecular docking and molecular dynamics simulations to investigate the molecular mechanisms of three selected Cassipourea metabolites in the treatment of melasma. Results Of the 202 genes obtained from the 14 profiled metabolites, only PTGS2, TYR, ESR2, and ESR1 were common among metabolites and targets implicated in melasma. From this, The gene ontology highlighted the intracellular steroid hormone receptor, signalling pathway, macromolecular complex, and estrogen receptor activity as the top enriched functional annotations, while the KEGG pathway analysis identified five signalling pathways, from which the prolactin signalling pathway, endocrine resistance, and estrogen signalling pathway were implicated in the pathogenesis of melasma. These pathways were further connected by their linkage to ESR2 and ESR1., Of all Cassipourea metabolites and standards, with afzelechin having the highest docking score for both gens. Further binding interaction analysis showed that ESR2-bound tamoxifen had the highest binding free energy of -47.68 kcal/mol, however, among the interacting Cassipourea metabolites, sitosterol-glycoside exhibited the highest negative binding affinity for both ESR2 (-40.50 kcal/mol) and ESR1 (-78.97 kcal/mol) over 150 ns simulation, suggesting its potential as a dual modulator. Altogether, the metabolites presented remarkable binding stability and thermodynamic compactness with the apo-genes. Conclusion The finding that the selected Cassipourea metabolites are associated with the genes and enzymes implicated in melasma pathogenesis, together with their significant binding effects on the enriched genes, suggests their regulatory potential on the profiled targets and, consequently, in the treatment of melasma.

Oxidative Stress in Patients With Melasma: An Evaluation of the Correlation of the Thiol/Disulfide Homeostasis Parameters and Modified MASI Score.

Melasma is a common acquired hyperpigmentation disorder that affects mostly women and individuals with darker skin types. Oxidative stress may play a role in the pathogenesis of melasma. Dynamic thiol/disulfide homeostasis is one of the most important indicators of oxidative stress. This study aimed to investigate the presence of oxidative stress in patients with melasma by evaluating thiol/disulfide homeostasis. Sixty-seven patients with melasma and 41 healthy age- and sex-matched controls were included in the study. Disease severity was evaluated using the modified melasma area and severity index (mMASI). Thiol/disulfide homeostasis parameters of the melasma and control groups were measured using a novel, fully automated spectrophotometric method. Our data indicated the presence of oxidative stress in melasma, which may be correlated with disease severity. Because research on the presence of oxidative stress in melasma is limited, further studies are needed to support these conclusions.

Squamous cell carcinoma of the nail in patients with Fitzpatrick phototypes IV-VI: a systematic review.

Squamous cell carcinoma of the nail unit (nSCC) is a rare malignant tumor of the hand and nail. Although skin cancer rarely affects individuals with phototypes IV-VI, its occurrence in these groups is often associated with greater morbidity and mortality. This study aims to characterize the clinical symptoms, presentations, and treatments of nSCC in patients with darker skin types. A systematic review of PubMed and Embase was performedin May 2023 for all peer-reviewed, English-language nSCC studies involving individuals with Fitzpatrick types IV-VI. Most tumors were located on the fingernails (84%), with the right third finger being the most frequently affected (31%). The nail bed (67%) exhibited a higher prevalence than the lateral/proximal nail folds (33%). The duration of symptoms before diagnosis ranged from 1 month to 7 years. nSCC was most commonly treated with Mohs surgery (38%), followed by amputation (35%). Our study was limited to case reports because of a lack of large nSCC studies that provide information on race or images of each patient. These tumors are generally slow-growing yet often misdiagnosed, leading to delays in presentation and diagnosis. Increased awareness about nSCC in phototype IV-VI individuals will reduce misdiagnoses, unnecessary treatment, and recurrences.

Editor's Highlights - May 2024.

Dermatological research and education have predominantly focused on lighter skin types in the past, leading to a significant gap in knowledge and understanding of conditions in darker skin types. This has contributed to disparities in the diagnosis and treatment of diseases in patients with skin of color. In the current issue of the Journal, we highlight four papers on the epidemiology and clinics of skin of color patients but also emphasize the importance of education and research in the dermatopathology of SOC patients.

A practical guide to over‐the‐counter treatments for hyperpigmentation

AbstractHyperpigmentation of the skin, defined as increased melanin in the epidermis, is a common condition associated with psychosocial impairment and decreased quality of life. Prescription options are often not covered by insurance and can be cost prohibitive. As such, many turn to over‐the‐counter (OTC) products for treatment. However, a plethora of options are available, which can be confusing. This review aims to evaluate the evidence for common ingredients found in OTC products for management of hyperpigmentation and provide guidance for optimal use to clinicians and consumers. To perform this review, a comprehensive literature search utilizing PubMed and Google Scholar was conducted to identify relevant studies on the clinico‐epidemiological aspects of hyperpigmentation, including postinflammatory hyperpigmentation (PIH), melasma and maturational hyperpigmentation, as well as on relevant OTC treatments. The efficacy and safety of OTC products were assessed based on available evidence, clinical trials and expert recommendations. Our results showed hyperpigmentation is more prevalent among individuals with darker skin types (Fitzpatrick skin phototypes III–VI). Due to limited insurance coverage and the high cost of prescription options, over‐the‐counter (OTC) treatments are widely used for managing postinflammatory hyperpigmentation (PIH). However, the lack of strict regulation by the US Food and Drug Administration (FDA) raises concerns about the safety and efficacy of these products. By critically evaluating the existing literature, this review offers practical, evidence‐based guidance for the selection and utilization of OTC products for the treatment of hyperpigmentation.

MELASMA ETIOLOGY AND TREATMENT: A SYSTEMATIC REVIEW

Introduction: Melasma is a common chronic refractory pigmentation disorder that predominantly affects women and individuals with darker skin types. It significantly alters quality of life and self-esteem because of its disfiguring skin appearance. Objective: to detail current information related to melasma, etiology, epidemiology, pathophysiology, histology, presentation, treatment and prognosis. Methodology: a total of 30 articles were analyzed in this review, including review and original articles, as well as clinical cases, of which 19 bibliographies were used because the other articles were not relevant to this study. The sources of information were PubMed, Google Scholar and Cochrane; the terms used to search for information in Spanish, Portuguese and English were: melasma, laser, pigmentation, skin. Results: Females are more affected than males in a 9:1 ratio. Melasma is infrequent prior to puberty and more common in the reproductive years. Melasma is found in 15% and 50% of pregnant women. The prevalence is 1.5% and 33% depending on the population. The most notable factor is exposure to sunlight. Next to pregnancy, direct sun exposure is the most important risk factor for melasma, shown by 27% to 51% of individuals as a trigger and 84% as a clinical deterioration factor. Approximately 83% to 93% of individuals with melasma have modifiable levels of solar elastosis. Conclusions: The treatment of melasma continues to be a challenge, because of the fact that the spots do not disappear completely in most of those affected, in addition to presenting considerable recurrence rates. The first line management is adequate sun protection and the association of sunscreens with color and topical bleaching agents, which may have a different effect on melanogenesis. In case oral medications are needed, tranexamic acid presents the best evidence for treatment. Some procedures support the treatment of melasma, such as microneedling and chemical peels that act through epidermal renewal. Lasers should be used with extreme caution because heat induces post-inflammatory melanogenesis. The combination of topical bleaching agents with medications and oral procedures provides more rapid effects, however more studies are needed regarding the treatment of the condition. KEY WORDS: melasma, laser, pigmentation, skin.

P09 A prospective study of Narrowband UVB (nb-UVB) Phototherapy for atopic dermatitis (AD) in children and adolescents.

Abstract We evaluated response to thrice weekly nb-UVB for AD (maximum 40 exposures), to assess outcomes immediately post-treatment and 12 months later. Post-treatment follow up was 3 monthly for 12 months. We sub-analysed response in different ethnicities. 58 patients were recruited: 37 (64%) male, 21 (36%) female, age-range 4.1-16.9 (mean 10.6) years. Ethnicities were: White Caucasian 22 (38%), Southern Asian (Pakistani/Indian/Bangladeshi) 17 (29%), Black African/Caribbean 9 (16%), Other 10 (17%). Immediately post-treatment, EASI 75 was achieved in: Overall 49%, Caucasian 48%, Southern Asian 50%, African-Caribbean 44%, other 56%. Mean EASI reduction was: Whole group 10.0, Caucasian 12.4, Southern Asian 8.6, African-Caribbean 2.5, Other 7.5. 12 months post-treatment (compared to pre-treatment), EASI 75 was achieved in: Overall 28%, Caucasian 33%, Southern Asian 40%, African-Caribbean14%, other 13%. Mean EASI reduction was: Whole group 7.6, Caucasian 9.0, Southern Asian 8.6, African-Caribbean -2.1 (worsening), Other 8.0. Erythema was the most common side effect noted in 33% of patients, the incidence in Caucasians 50% (n=11), other 30% (n=3), African-Caribbean 22% (n=2) and Southern Asian 12% (n=2). A similar proportion achieved EASI 75 across the different skin types, however, more variation in EASI score reduction was noted in skin of colour. A lower incidence of post-treatment erythema noted in darker skin types may be due to erythema underscoring or treatment underdosing. Our study showed sustained AD improvement up to a year after stopping treatment in 28% overall, highest in Caucasian and Southern Asian patients, with greater risk of relapse noted in African-Caribbean patients.

Efficacy and safety of diode laser for facial hair reduction in hirsutism-a clinico-trichoscopic evaluation.

Hirsutism is the presence of excessive terminal hair on androgen-dependent sites of the body. Lasers like Alexandrite, diode, and Nd:Yag lasers have been used for hair reduction with varying efficacy. Trichoscopy of hair is a simple noninvasive method of hair assessment. However, it has not been used in the assessment of diode laser hair reduction. This study aimed to assess the efficacy and safety of diode laser hair reduction in skin color with the help of clinical and trichoscopic assessment. This prospective observational study included 73 patients of hirsutism recruited in 18-month period. All participants received sessions of 805 nm diode laser at monthly intervals up to six sessions. Clinical and trichoscopic evaluation along with photographs were obtained at each visit. Side effects, if any, were noted in every sitting. All patients were females of Fitzpatrick skin types III-V. All clinical parameters showed statistically significant hair reduction when compared with baseline. Trichoscopic parameters of hair reduction like total hair count, terminal hair count, and terminal/vellus hair ratio showed reduction compared to baseline which was statistically significant (P < 0.05). The most common side effect noted in our study was pain followed by erythema and perifollicular edema. Diode laser is an effective and safe procedure for the reduction of unwanted facial hair, even in darker skin types. We also wish to emphasize that trichoscopy for the assessment of laser hair reduction is a recent, noninvasive, simple, and underutilized tool. No serious adverse events were noted in our study.

Integrated sun protection advice for the South African population.

Exposure to solar ultraviolet radiation (UVR) is associated with several cutaneous adverse effects. However, to the best of our knowledge, in South Africa there are no formal guidelines on sun protection. A group of South African dermatologists and researchers convened over the course of 1 year to deliberate on integrated advice for sun protection among the multi-ethnic South African population. For people with light skin and those with genetic skin disorders (e.g., oculocutaneous albinism), sun protection was identified as critical to prevent sunburn, skin cancer, and photoaging. The evidence is less clear for people with medium and darker skin types, especially the latter, in whom melanin may confer a degree of protection against some parts of the solar spectrum. Recent studies have demonstrated that visible light can cause pigmentary changes in individuals with darker skin types in particular. Sun protection for people of all skin colors is beneficial to protect against photoaging and ocular damage. Herein sun protection advice is suggested for South Africans of all skin colors to reduce morbidity and mortality from sun exposure, particularly relating to skin cancer. Several knowledge gaps are identified as future research priorities.

42807 A comparative study of the efficacy of oral omega-3 polyunsaturated fatty acids vectorized in marine phospholipids to prevent the post-inflammatory hyperpigmentation in dark skin types after a non-ablative laser

42807 A comparative study of the efficacy of oral omega-3 polyunsaturated fatty acids vectorized in marine phospholipids to prevent the post-inflammatory hyperpigmentation in dark skin types after a non-ablative laser

Melasma in people with darker skin types: a scoping review protocol on prevalence, treatment options for melasma and impact on quality of life

BackgroundMelasma is one of the most encountered dermatoses in dermatology and skin care clinics. It is a challenging chronic, recurrent condition associated with hyperpigmentation. Its aetiology is poorly understood. Melasma affects all races and gender but is more prevalent in women with darker skin types. Being a facial lesion, melasma has a severe impact on quality of life due to its disfigurement. While many modalities of treatment for melasma exists, unfortunately, effectiveness and safety remain a huge concern. Treatment modalities are variable and often unsatisfactory. The objective of this scoping review is to systemically map available evidence from literature regarding melasma on people with darker skin types, garner insight as to how melasma affects the quality of life and begin to investigate and gain understanding on effectiveness of different treatments used for melasma.MethodsA scoping review guided by Arksey and O’Malley’s framework, the enhancements and recommendations of Levac, Colquhoun and O’Brien, Daudt and associates and the 2015 Johanna Briggs Institute’s guidelines will be conducted. Systematic electronic searches of databases and search engines will include Scopus, PubMed, CINAHL Complete, Cochrane, Science Direct, and Web of Science which will be conducted to attain published peer-reviewed articles of all study designs excluding reviews and grey literature. All literature that meets the inclusion criteria, research question and sub-question will be included in this review. All the retrieved literature will be exported to an Endnote X20 library. Quality appraisal of the included articles will be conducted using the mixed methods appraisal tool (MMAT) 2018 version.DiscussionWe anticipate mapping relevant literature on the melasma, investigating the effectiveness of treatment options of melasma as well as evaluating its association with quality of life in people with darker skin types. This study is likely to reveal research gaps, which could guide future implementation research on melasma treatment interventions.Systematic review registrationThis protocol has been registered a priori with OSF and is accessible on this link: https://osf.io/ru3jc/.

Far-UVC- and UVB-induced DNA damage depending on skin type.

Far-UVC radiation sources of wavelengths 222 nm and 233 nm represent an interesting potential alternative for the antiseptic treatment of the skin due to their high skin compatibility. Nevertheless, no studies on far-UVC-induced DNA damage in different skin types have been published to date, which this study aims for. After irradiating the skin with far-UVC of the wavelengths 222 and 233 nm as well as broadband UVB, the tissue was screened for cyclobutane pyrimidine dimer-positive (CPD+ ) cells using immunohistochemistry. The epidermal DNA damage was lower in dark skin types than in fair skin types after irradiation at 233 nm. Contrary to this, irradiation at 222 nm caused no skin type-dependent differences, which can be attributed to the decreased penetration depth of radiation. UVB showed the relatively strongest differences between light and dark skin types when using a suberythemal dose of 3 mJ/cm2 . As melanin is known for its photoprotective effect, we evaluated the ratio of melanin content in the stratum basale and stratum granulosum in samples of different skin types using two-photon excited fluorescence lifetime imaging (TPE-FLIM) finding a higher ratio up to skin type IV-V. As far-UVC is known to penetrate only into the upper layers of the viable skin, the aforementioned melanin ratio could explain the less pronounced differences between skin types after irradiation with far-UVC compared to UVB.

Multispectral Imaging for Vein Localization and Contrast Enhancement.

Intravenous (IV) catheterization is a common procedure. Still, there is a 26% chance of the first attempt catheterization failure due to the changing visibility of veins because of the patient's skin tone and body fat content. Ultrasound assistive devices help locate deeper veins but are not practical in emergencies, and transillumination assistive devices have a low field of view. Commercial near-infrared (NIR) imaging devices are effective in vein localization but are expensive and are not used in low-cost clinical settings. To overcome this, NIR Multispectral Imaging (MSI) was used to find the optimal wavelength that provides the enhanced visualization of veins for all skin types and Body Mass Index (BMI). The band with the highest vein-to-skin contrast ratio was selected and contrast enhancement was done using our proposed method. The primary blocks of the proposed method are Gamma correction, Contrast Limited Adaptive Histogram Equalization (CLAHE), Adaptive Thresholding, and image Fusion. The optimal spectral range was found to be 814-876 nm and our method increased the contrast by 0.41, 0.375, and 0.39 for fair, brown, and dark brown skin types, respectively, with different BMI.Clinical relevance- From the study, we can develop a potentially low-cost vein localization assistive device for training medical and nursing students and use it in emergencies for venous access to improve confidence in IV catheterization.

Understanding the Factors Associated with US Dermatology Resident Trainees' Diagnostic Confidence and Skill for Skin of Color Pathology

Background: Inequities in dermatologic health outcomes translate to worsened clinical outcomes for minority groups. For example, despite a lower incidence of skin cancer overall, African Americans are diagnosed at later stages with greater degrees of lymph node involvement. This has been shown to lead to disproportionate mortality when compared to lighter skinned individuals. Medical education materials contain a significantly lower percentage of skin of color (SOC) images than of lighter skin and research has indicated lower diagnostic accuracy of dermatologic conditions in darker skin by U.S. medical students. The objective of this study was to explore U.S. resident dermatologists’ ability to accurately identify skin pathology among SOC patients verus lighter skin to potentially identify gaps in training that may contribute to this disproportionate morbidity and mortality. Methods: A cross-sectional electronic REDCap survey open to all U.S. dermatology residents asked participants their basic demographics (e.g., level of training, racial and ethnic identity) and program characteristics (e.g., geographical location, proportion of patients by Fitzpatrick type, presence of a dedicated SOC clinic). This data was correlated with participant visual diagnostic accuracy on a 22-item multiple choice quiz (images selected by a senior academic dermatologist) of characteristic nonmalignant and malignant conditions in lighter skin and SOC. Results: Residents preferentially misdiagnosed malignant lesions in SOC over lighter skin (p &lt;.0001) and preferentially misdiagnosed malignant lesions in SOC over nonmalignant lesions in SOC (p &lt;.001). None of the residents’ basic demographic or program characteristic variables had significant relationships with any assessment of performance. Conclusion: Dermatologists should maintain a high clinical suspicion for malignant conditions in patients with darker skin types, given that these lesions are the most preferentially misdiagnosed and the fact that these lesions carry higher risks for morbidity and mortality. Dermatology residency programs should instill efforts to emphasize correct detection of malignant lesions amongst those with skin of color.

DP05 (P53) Incidence of Merkel cell carcinoma in the Republic of Ireland (1994–2019)

Abstract Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine cutaneous malignancy most commonly observed in those aged over 65 years. Merkel cell carcinoma is twice as common in males as in females and is 25 times more common in those with fair skin than in those with darker skin types. Solid organ transplant recipients have a 24-fold increased risk of developing MCC. There was a 95% increase in the incidence of MCC in the USA from 2000 to 2013, with further increases predicted. The aim of this study was to investigate the trends of incidence of MCC in the Republic of Ireland. Age-standardized rates were calculated using the 2013 European standard population. There were 447 histologically confirmed MCCs diagnosed between 1994 and 2019. Forty-nine per cent of cases (n = 220) were in males. Median age was 80 years (range 15–19 to 95+). The median age for males was 78 years and the median age for females was 82 years. On average, there were seven cases of MCC diagnosed annually between 1994 and 1998 vs. 27 cases of MCC annually diagnosed between 2015 and 2019—almost a quadrupling of case numbers. The age-adjusted incidence rate of MCC for both male and females is detailed in Table 1. Previous literature has indicated that MCC is twice as common in males than in females. Our cohort differed in that there was a slight female predominance in patients diagnosed with MCC. This is in keeping with published literature from Northern European groups, which have also demonstrated a female predominance in MCC. While the absolute number of MCC diagnosed in Ireland has increased in both males and females, the age-adjusted incidence rate is increasing in males, but there has not been a significant change in females. Other Northern European groups have also demonstrated an increase in the incidence of MCC in males that was not observed in females. This study adds to the body of epidemiological data on MCC. Table 1Age-adjusted incidence rates of Merkel cell carcinoma (MCC)Cases of MCCAge-standardized rate (per 100 000 person-years)SE95% confidence intervalMales 1994–1999230.520.130.27–0.77 2000–2004210.370.080.21–0.53 2005–2009350.790.150.50–1.08 2010–2014661.190.160.88–1.50 2015–2019751.050.120.81–1.29Females 1994–1999260.360.070.22–0.50 2000–2004440.670.100.47–0.87 2005–2009540.790.110.57–1.01 2010–2014450.570.090.39–0.75 2015–2019580.650.090.47–0.83

PD09 A prospective study of outcomes of narrowband ultraviolet B for the treatment of paediatric atopic dermatitis, with additional breakdown by ethnicity/skin type

Abstract Narrowband UVB (NBUVB) phototherapy is regarded as a second-line treatment for atopic dermatitis (AD) when response to first-line treatment is ineffective. We undertook a prospective study evaluating response to NBUVB treatment in paediatric AD to assess changes to pretreatment Eczema Area and Severity Index (EASI) score immediately postphototherapy and 12 months later. We subanalysed response in different skin types. All patients had NBUVB treatment three times weekly up to a maximum of 40 exposures. Follow-up was every 3 months for 1 year postphototherapy. In total, 58 patients were recruited for NBUVB phototherapy treatment [37 (64%) men, 21 (36%) women, mean age 10.6 years (range 4.1–16.9 years)]. Skin types/ethnicity were as follows: White, n = 22 (38%); South Asian (Pakistani/Indian/Bangladeshi), n = 17 (29%); Black African/Caribbean, n = 9 (16%); other, n = 10 (17%). The immediate post-treatment mean EASI reductions vs. pretreatment baseline scores were 10.0 (entire cohort), 12.4 (White), 8.6 (South Asian), 2.5 (Black African/Caribbean) and 7.5 (other). A ≥ 75% increase in EASI (EASI 75) was achieved in the 49% of the entire cohort, in 48% of White people, in 50% of South Asians, in 44% of Black African/Caribbean people and in 56% of others. A ≥ 90% increase in EASI (EASI 90) was achieved in 15% of the whole group, 14% of White people, 13% of South Asians, 22% of Black African/Caribbean people and 11% of others. At 12 months post-treatment, mean EASI reduction vs. pretreatment baseline score was 7.6 in the whole cohort, 9.0 in White people, 8.6 in South Asians, −2.1 (i.e. worsening) in Black African/Caribbean people and 8.0 in others. At 12 months post-treatment, EASI 75 was achieved in 28% of the whole group, 33% of White people, 40% of South Asians, 14% of Black African/Caribbean people and 13% of others. For those who responded, there were a similar proportion of those achieving EASI 75 across the different skin types. However, there was more variation in the reduction in EASI score in those with skin colour. We acknowledge that existing scoring systems may lead to underscoring of the severity of erythema and therefore overall EASI score in darker skin types. Although the mean EASI reduction was highest in the group of White patients, there was a higher proportion of Black/Caribbean patients achieving EASI 90 at the end of the NBUVB treatment; however, the overall number of patients in this group was small. Our study showed that White and South Asian paediatric patients had a more sustained response to NBUVB phototherapy up to 1 year after stopping treatment. Black African/Caribbean patients had a greater risk of relapse.

P53 Incidence of merkel cell carcinoma in the Republic of Ireland (1994–2019)

Abstract Merkel cell carcinoma (MCC) is a rare, aggressive, neuroendocrine cutaneous malignancy most commonly observed in those aged over 65 years. MCC is twice as common in males as in females and is 25 times more common in those with fair skin than in those with darker skin types. Solid organ transplant recipients have a 24-fold increased risk of developing MCC. There has been a 95% increase in the incidence of MCC in the USA from 2000 to 2013, with further increases predicted. The aim of this study was to investigate the trends of incidence of MCC in the Republic of Ireland. Age-standardized rates were calculated using the 2013 European standard population. There were 447 histologically confirmed MCCs diagnosed between 1994 and 2019. Forty-nine per cent of cases (n = 220) were in males. Median age was 80 years (range 15–19 to 95+). The median age for males was 78 years and the median age for females was 82 years. On average, there were seven cases of MCC diagnosed annually between 1994 and 1998 vs. 27 cases of MCC annually diagnosed between 2015 and 2019—almost a quadrupling of case numbers. The age-adjusted incidence rate of MCC for both male and females is detailed in Table 1. Previous literature has indicated that MCC is twice as common in males than in females. Our cohort differed in that there was a slight female predominance in patients diagnosed with MCC. This is in keeping with published literature from Northern European groups, which have also demonstrated a female predominance in MCC. While the absolute number of MCC diagnosed in Ireland has increased in both males and females, the age-adjusted incidence rate is increasing in males, but there has not been a significant change in females. Other Northern European groups have also demonstrated an increase in the incidence of MCC in males that was not observed in females. This study adds to the body of epidemiological data on MCC.Table 1Age-adjusted incidence rates of Merkel cell carcinoma (MCC)Cases of MCCAge-standardized rate (per 100 000 person years)SE95% confidence intervalMales1994–1999230.520.130.27–0.772000–2004210.370.080.21–0.532005–2009350.790.150.50–1.082010–2014661.190.160.88–1.502015–2019751.050.120.81–1.29Females1994–1999260.360.070.22–0.502000–2004440.670.100.47–0.872005–2009540.790.110.57–1.012010–2014450.570.090.39–0.752015–2019580.650.090.47–0.83