Are the Fitzpatrick Skin Phototypes Valid for Cancer Risk Assessment in a Racially and Ethnically Diverse Sample of Women?

A survey of skin tone assessment in prospective research

Increasing evidence supports reduced accuracy of noninvasive assessment tools, such as pulse oximetry, temperature probes, and AI skin diagnosis benchmarks, in patients with darker skin tones. The FDA is exploring potential strategies for device regulation to improve performance across diverse skin tones by including skin tone criteria. However, there is no consensus about how prospective studies should perform skin tone assessment in order to take this bias into account. There are several tools available to conduct skin tone assessments including administered visual scales (e.g., Fitzpatrick Skin Type, Pantone, Monk Skin Tone) and color measurement tools (e.g., reflectance colorimeters, reflectance spectrophotometers, cameras), although none are consistently used or validated across multiple medical domains. Accurate and consistent skin tone measurement depends on many factors including standardized environments, lighting, body parts assessed, patient conditions, and choice of skin tone assessment tool(s). As race and ethnicity are inadequate proxies for skin tone, these considerations can be helpful in standardizing the effect of skin tone on studies such as AI dermatology diagnoses, pulse oximetry, and temporal thermometers. Skin tone bias in medical devices is likely due to systemic factors that lead to inadequate validation across diverse skin tones. There is an opportunity for researchers to use skin tone assessment methods with standardized considerations in prospective studies of noninvasive tools that may be affected by skin tone. We propose considerations that researchers must take in order to improve device robustness to skin tone bias.

Melanometry for objective evaluation of skin pigmentation in pulse oximetry studies

Pulse oximetry enables real-time, noninvasive monitoring of arterial blood oxygen levels. However, results can vary with skin color, thus detecting disparities during clinical validation studies requires an accurate measure of skin pigmentation. Recent clinical studies have used subjective methods such as self-reported color, race/ethnicity to categorize skin. Melanometers based on optical reflectance may offer a more effective, objective approach to assess pigmentation. Here, we review melanometry approaches and assess evidence supporting their use as clinical research tools. We compare performance data, including repeatability, robustness to confounders, and compare devices to each other, to subjective methods, and high-quality references. Finally, we propose best practices for evaluating melanometers and discuss alternate optical approaches that may improve accuracy. Whilst evidence indicates that melanometers can provide superior performance to subjective approaches, we encourage additional research and standardization efforts, as these are needed to ensure consistent and reliable results in clinical studies.

Epidemiological and clinical analysis of exposure-related factors in non-melanoma skin cancer: A retrospective cohort study

BACKGROUND

The incidence of non-melanoma skin cancers (NMSCs) increased over last decades, probably due to environmental concerns or to the increase of frail patients with age related comorbidities. Currently, the relationship of increasing global skin cancer rates with increased ultraviolet radiations (UVRs) resulting from stratospheric ozone depletion, global warming, and air pollution from fossil-fuel combustion.

AIMS

We conducted a retrospective epidemiological study including 546 NMSC patients managed at the Dermatology Unit of the Tor Vergata Hospital to highlight different trends of sun exposure or different comorbidities.

METHODS

Descriptive and inferential statistical analyses were performed to evidence differences between continous variable and Spearman rank test for dicotomical variables. Charlson Comorbidity Index was calculated to obtain the 10-years survival rate in order to identify the mean comorbidity burden of our patients.

RESULTS

Considering patients with comorbidities (73.81%), actinic keratoses (AKs) was the most frequent lesion. In patients with a history of previous melanoma, basal cell carcinoma (BCC) was predominant (ANOVA test, p < 0.05) with a statistically significant correlation (rho = 0.453; p < 0.01). Squamous cell carcinoma (SCC) showed a higher rate in arterial hypertension patients, followed by the chronic heart failure and hematologic neoplasms (60%, 29.7% and 32.1%, respectively) groups. Men were more affected than women, representing 61.54% of patients. Chronic sun exposure is directly correlated with SCC rho = 0.561; p < 0.01), whereas BCC correlated with a history of sunburns (rho = 0.312; p < 0.05).

CONCLUSIONS

History of photo-exposition had an important role on NMSC development especially for work or recreational reasons. Sex, age, and presence of comorbidities influenced different NMSC types. BCC was more frequent in younger patients, associated with melanoma and sunburns. The presence of SCC is associated with older patients and the hypertension group. AKs were diagnosed predominantly in oldest men, with a chronic sun-exposure history, and hematologic neoplasms group.

Artificial intelligence in dermatology: advancements and challenges in skin of color

Artificial intelligence (AI) uses algorithms and large language models in computers to simulate human-like problem-solving and decision-making. AI programs have recently acquired widespread popularity in the field of dermatology through the application of online tools in the assessment, diagnosis, and treatment of skin conditions. A literature review was conducted using PubMed and Google Scholar analyzing recent literature (from the last 10 years through October 2023) to evaluate current AI programs in use for dermatologic purposes, identifying challenges in this technology when applied to skin of color (SOC), and proposing future steps to enhance the role of AI in dermatologic practice. Challenges surrounding AI and its application to SOC stem from the underrepresentation of SOC in datasets and issues with image quality and standardization. With these existing issues, current AI programs inevitably do worse at identifying lesions in SOC. Additionally, only 30% of the programs identified in this review had data reported on their use in dermatology, specifically in SOC. Significant development of these applications is required for the accurate depiction of darker skin tone images in datasets. More research is warranted in the future to better understand the efficacy of AI in aiding diagnosis and treatment options for SOC patients.

PTCH1 Gene Variants, mRNA Expression, and Bioinformatics Insights in Mexican Cutaneous Squamous Cell Carcinoma Patients

BACKGROUND

Skin cancer is one of the most frequent types of cancer, and cutaneous squamous cell carcinoma (cSCC) constitutes 20% of non-melanoma skin cancer (NMSC) cases. PTCH1, a tumor suppressor gene involved in the Sonic hedgehog signaling pathway, plays a crucial role in neoplastic processes.

METHODS

An analytical cross-sectional study, encompassing 211 cSCC patients and 290 individuals in a control group (CG), was performed. A subgroup of samples was considered for the relative expression analysis, and the results were obtained using quantitative real-time PCR (qPCR) with TaqMan® probes. The functional, splicing, and disease-causing effects of the proposed variants were explored via bioinformatics.

RESULTS

cSCC was predominant in men, especially in sun-exposed areas such as the head and neck. No statistically significant differences were found regarding the rs357564, rs2236405, rs2297086, and rs41313327 variants of PTCH1, or in the risk of cSCC, nor in the mRNA expression between the cSCC group and CG. A functional effect of rs357564 and a disease-causing relation to rs41313327 was identified.

CONCLUSION

The proposed variants were not associated with cSCC risk in this Mexican population, but we recognize the need for analyzing larger population groups to elucidate the disease-causing role of rare variants.

HyperVein: A Hyperspectral Image Dataset for Human Vein Detection

HyperSpectral Imaging (HSI) plays a pivotal role in various fields, including medical diagnostics, where precise human vein detection is crucial. HyperSpectral (HS) image data are very large and can cause computational complexities. Dimensionality reduction techniques are often employed to streamline HS image data processing. This paper presents a HS image dataset encompassing left- and right-hand images captured from 100 subjects with varying skin tones. The dataset was annotated using anatomical data to represent vein and non-vein areas within the images. This dataset is utilised to explore the effectiveness of dimensionality reduction techniques, namely: Principal Component Analysis (PCA), Folded PCA (FPCA), and Ward's Linkage Strategy using Mutual Information (WaLuMI) for vein detection. To generate experimental results, the HS image dataset was divided into train and test datasets. Optimum performing parameters for each of the dimensionality reduction techniques in conjunction with the Support Vector Machine (SVM) binary classification were determined using the Training dataset. The performance of the three dimensionality reduction-based vein detection methods was then assessed and compared using the test image dataset. Results show that the FPCA-based method outperforms the other two methods in terms of accuracy. For visualization purposes, the classification prediction image for each technique is post-processed using morphological operators, and results show the significant potential of HS imaging in vein detection.

Describing skin health and disease in urban-living Aboriginal children: co-design, development and feasibility testing of the Koolungar Moorditj Healthy Skin pilot project

BACKGROUND

Indigenous children in colonised nations experience high rates of health disparities linked to historical trauma resulting from displacement and dispossession, as well as ongoing systemic racism. Skin infections and their complications are one such health inequity, with the highest global burden described in remote-living Australian Aboriginal and/or Torres Strait Islander (hereafter respectfully referred to as Aboriginal) children. Yet despite increasing urbanisation, little is known about the skin infection burden for urban-living Aboriginal children. More knowledge is needed to inform service provision, treatment guidelines and community-wide healthy skin strategies. In this pilot study, we aimed to test the feasibility and design of larger multi-site observational studies, provide initial descriptions of skin disease frequency and generate preliminary hypotheses of association.

METHODS

This project has been co-designed with local (Noongar) Elders to provide an Australian-first description of skin health and disease in urban-living Aboriginal children. In collaboration with an urban Aboriginal Community Controlled Health Organisation (Derbarl Yerrigan Health Service), we conducted a week-long cross-sectional observational cohort study of Aboriginal children (0-18 years) recruited from the waiting room. Participants completed a questionnaire, skin examination, clinical photos, and swabs and received appropriate treatment. We assessed the feasibility and impact of the pilot study.

RESULTS

From 4 to 8 October 2021, we recruited 84 Aboriginal children of whom 80 (95%) were urban-living. With a trusted Aboriginal Health Practitioner leading recruitment, most parents (or caregivers) who were approached consented to participate. Among urban-living children, over half (45/80, 56%) of parents described a current concern with their child's skin, hair and/or nails; and one-third (26/80, 33%) reported current itchy skin. Using a research-service model, 27% (21/79) of examined urban-living participants received opportunistic same-day treatment and 18% (14/79) were referred for later review.

CONCLUSIONS

This co-designed pilot study to understand skin health in urban-living Aboriginal children was feasible and acceptable, with high study participation and subsequent engagement in clinical care observed. Co-design and the strong involvement of Aboriginal people to lead and deliver the project was crucial. The successful pilot has informed larger, multi-site observational studies to more accurately answer questions of disease burden and inform the development of healthy skin messages for urban-living Aboriginal children.

Melanoma in skin of color: Part II. Racial disparities, role of UV, and interventions for earlier detection

Despite a higher incidence of melanoma among White individuals, melanoma-specific survival is worse among individuals with skin of color. Racial disparities in survival are multifactorial. Decreased skin cancer education focused on people with skin of color, lower rates of screening, increased socioeconomic barriers, higher proportions of more aggressive subtypes, and underrepresentation in research and professional education contribute to delays in diagnosis and treatment. Although high, intermittent UV exposure during childhood has been established as a significant modifiable risk factor for melanoma in individuals with lighter skin phototypes, there are limited data on UV exposure and melanoma risk in people with darker skin phototypes. The second article of this continuing medical education series will examine factors contributing to racial disparities in melanoma-specific survival, discuss the role of UV radiation, and address the need for further research and targeted educational interventions for melanoma in individuals with skin of color.

Endogenous Photosensitizers in Human Skin

Endogenous photosensitizers play a critical role in both beneficial and harmful light-induced transformations in biological systems. Understanding their mode of action is essential for advancing fields such as photomedicine, photoredox catalysis, environmental science, and the development of sun care products. This review offers a comprehensive analysis of endogenous photosensitizers in human skin, investigating the connections between their electronic excitation and the subsequent activation or damage of organic biomolecules. We gather the physicochemical and photochemical properties of key endogenous photosensitizers and examine the relationships between their chemical reactivity, location within the skin, and the primary biochemical events following solar radiation exposure, along with their influence on skin physiology and pathology. An important take-home message of this review is that photosensitization allows visible light and UV-A radiation to have large effects on skin. The analysis presented here unveils potential causes for the continuous increase in global skin cancer cases and emphasizes the limitations of current sun protection approaches.

Updating the Fitzpatrick Classification: The Skin Color and Ethnicity Scale

BACKGROUND

There has been a significant increase in submissions to scientific journals addressing a broad spectrum of medical and surgical conditions in subjects grouped under the classification of "Skin of Color." Authors, reviewers, and editors have struggled with accurate terminology.

OBJECTIVE

To update the Fitzpatrick scale to make it more accurate in stratifying various shades of skin color.

MATERIALS AND METHODS

A thorough literature review was performed using PubMed and Embase to assess existing skin color scales, and an extensive internet search was conducted using makeup foundation ranges as a starting point for skin tone matching.

RESULTS

The research resulted in a consensus that Fitzpatrick types 4 and 5 ratings were the most confusing in that these included a broad range of skin types with different responses to solar radiation, lasers, surgery, and cosmetic products. The authors reached a consensus that subdividing skin types 4 and 5 into "A" and "B" better defined them. The new scale that resulted was labeled the SCE scale (for Skin Color Ethnicity).

CONCLUSION

This new updated SCE scale should assist authors in better reporting scientific data in skin of color.

MicroRNAs Involved in Oxidative Stress Processes Regulating Physiological and Pathological Responses

Oxidative stress influences several physiological and pathological cellular events, including cell differentiation, excessive growth, proliferation, apoptosis, and the inflammatory response. Therefore, oxidative stress is involved in the pathogenesis of various diseases, including pulmonary fibrosis, epilepsy, hypertension, atherosclerosis, Parkinson's disease, cardiovascular disease, and Alzheimer's disease. Recent studies have shown that several microRNAs (miRNAs) are involved in developing various diseases caused by oxidative stress and that miRNAs may be helpful to determine the inflammatory characteristics of immune responses during infection and disease. This review describes the known effects of miRNAs on reactive oxygen species to induce oxidative stress and the miRNA regulatory mechanisms involved in the uncoupling of Keap1-Nrf2 complexes. Finally, we summarized the functions of miRNAs in several antioxidant genes. Understanding the crosstalk between miRNAs and oxidative stress-inducing factors during physiological and pathological cellular events may have implications for designing more effective treatments for immune diseases.

The color of normal: How a Eurocentric focus erases pigmentation complexity

OBJECTIVES

Skin pigmentation is both a highly variable and highly visible human phenotypic trait. Investigations into the biology and origins of this variation have been the focus of research in the fields of dermatology, anthropology, and forensic science, among others. This manuscript explores how much of what we know about the biology, genetics, and evolutionary origins of pigmentation has been strongly influenced by investigations and applications that focus on lighter skin.

METHODS

I reviewed literature from the fields of dermatology, anthropology and evolutionary genetics, and forensic science to assess how perceptions of lighter skin as the "normal" state in humans can shape the ways that knowledge is gathered and applied in these fields.

RESULTS

This normalization of lighter skin has impacted common tools used in dermatology and shaped the framework of dermatological education. A strong Eurocentric bias has shaped our understanding of the genetic architecture of pigmentary traits, which influences the ways in we understand the evolutionary processes leading to modern pigmentation diversity. Finally, I discuss how these biases in pigmentation genetics work in combination with phenotypic systems that privilege predicting lighter pigmentation variation to impede accurate prediction of intermediate phenotypes, particularly in individuals with ancestry from multiple populations. This can lead to a disproportionate targeting of already over-policed populations with darker skin.

CONCLUSIONS

Potential changes to how we conceptualize clinical and basic pigmentation research may help to reduce existing health disparities and improve understanding of pigmentation genetic architecture and how this knowledge is applied in forensic contexts.

Validity of the Fitzpatrick Skin Phototype Classification in Ecuador

BACKGROUND

The Fitzpatrick Skin Phototype Classification (FSPC) is the most common tool used to assess skin phototype in White populations according to the amount of pigment the skin has and its reaction to sun exposure. Scientific evidence about the use of this scale for persons with darker skin is limited.

OBJECTIVE

To assess the internal consistency, reliability, and construct validity of the FSPC for Ecuadorians.

METHODS

This observational cross-sectional study recruited participants of both sexes between 40 and 90 years of age living in a rural area of Quito, Ecuador. Cronbach α values were used to assess the internal consistency of the scale. Construct validity was assessed with confirmatory factor analysis.

RESULTS

The internal consistency coefficients indicated that the reliability of the responses to the scale was fair. Total α value was .515, whereas the α values of the two factors were .42 and .67. Most item-to-factor correlations had a low to moderate magnitude, ranging from r = 0.30 to 0.37. Confirmatory factor analysis supported a two-factor solution and achieved good overall fit as indicated by root mean square error of approximation = 0.08, and nonnormed fit index = 0.88 was mediocre. Goodness-of-fit χ² = 177.10, P < .001. The factor loads were greater than 0.30, ranging from 0.30 to 0.99.

CONCLUSIONS

The FSPC showed an acceptable construct validity and a fair internal consistency. The five-item scale could potentially be used as an effective instrument for assessing skin phototype in non-White people.