Review Article |
Corresponding author: Clare Primiero ( c.bover@uq.edu.au ) Academic editor: Peter Wolf
© 2025 Sam Kahler, Chantal Rutjes, Monika Janda, H. Peter Soyer, Clare Primiero.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY-NC 4.0), which permits to copy and distribute the article for non-commercial purposes, provided that the article is not altered or modified and the original author and source are credited.
Citation:
Kahler S, Rutjes C, Janda M, Soyer HP, Primiero C (2025) The deep imaging phenotype for melanoma risk stratification. SKINdeep 1: e150261. https://doi.org/10.1553/skindeep.2025.150261
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Targeted surveillance for individuals at high-risk for melanoma is increasingly recognized as a feasible and effective alternative to population-wide melanoma screening. However, current risk stratification models to identify these high-risk individuals are often reliant on subjective or self-reported metrics, which are vulnerable to bias and poor reproducibility. The deep imaging phenotype describes the concept of leveraging parallel advances in total body photography (TBP) and artificial intelligence (AI) to improve risk stratification using personalized severity and spatial distribution of cutaneous risk factors. This narrative review explores the progress towards the deep imaging phenotype in dermatology, with a focus on its clinical applications, challenges, and future directions. It explores (i) the limitations of existing melanoma risk prediction, (ii) advancements in TBP and AI-driven analysis of the cutaneous phenotype; (iii) integration of phenotype with clinical and genomic information; (iv) frameworks for clinical, logistic, and ethical implementation of phenotypic measures into clinical practice. Progress towards the deep imaging phenotype has included algorithms that report nevus characteristics (count, size, and distribution), severity and distribution of photodamage, facultative and innate skin tones, freckling, and other parameters for objective and personalized risk stratification. Phenotypic measures correlate with melanoma risk and may be integrated with traditional clinical and genomic risk factors to enhance current risk assessment. Clinicians and consumers report acceptance of this approach, although, most evidence to date focuses on individual phenotypic features rather than the collective synergy of all measures. Supporting information technology infrastructure, legal frameworks, and clinical guidelines are underdeveloped and should be prioritized before clinical implementation. Objective risk stratification using personalized cutaneous risk factors may empower the effective allocation of resources, reduce over-surveillance in low-risk populations, and offer timely interventions to individuals at high risk.
Melanoma, AI, Artificial Intelligence, total body photography, risk prediction, skin cancer
Melanoma is a significant global public health challenge, with age-standardized incidence rates reaching 23 per 100,000 persons in Europe, 32 in the United States, and 54 in Australia. The clinical paradigm of early detection aims to identify high-risk, early-stage melanomas for surgical excision prior to the progression to metastasis, and aims to reduce morbidity, and mortality [
Accurate assessment of melanoma risk is highly reliant on contextualization through the clinical phenotype. Specifically, dermoscopy allows for the scrutiny of specific lesions for morphology that is correlated with the risk of metastasis. This dermoscopic information is integrated within an individual’s clinical phenotype, consisting of established and visual risk factors, to understand the holistic likelihood of melanoma [
A number of melanoma risk stratification tools have been developed to date but none have been systematically implemented into clinical practice. A major barrier to clinical implementation is an overreliance on subjective measures prone to invalidating bias, as was identified by a recent systematic review of risk prediction models [
Parallel advances in skin imaging technology and artificial intelligence (AI)-driven image analysis presents new opportunities to enhance traditional risk stratification based on an individual’s unique skin characteristics. This concept is described as the deep imaging phenotype, based on data obtained through total-body photography (TBP), dermoscopy, and questionnaires, analyzed using AI models to extract severity and spatial distribution of personalized risk factors for melanoma, including nevus pattern characteristics, photodamage, skin tone, and freckling [
This narrative review explores the progress of deep image phenotyping in dermatology, with a focus on its clinical applications, challenges, and future directions.
Deep imaging phenotype conceptualized with a 3D-TBP personalized avatar, integrated with (left to right): Site-specific skin tone; Nevus spiral map to visualize nevus count, size, and morphology; Body map with nevus tracking; Photodamage heatmaps mapping areas of mild (green), moderate (yellow), and severe (red) photodamage; Clinical information including genomics; Nevus spatial analysis identifying areas of clustered naevi compared to random or dispersed patterns; High-risk body region monitoring to detect local recurrence (scar) and adjacent sequential dermoscopy.
Greater nevus counts are amongst the strongest risk factors for cutaneous melanoma. The biological basis for the association between nevi and melanoma is through an increased genetic propensity for melanocyte proliferation that leads to the development of nevi, and in a subset of individuals a melanoma diagnosis [
Reproducible assessment of nevus counts has been a significant barrier to its implementation in melanoma risk assessment. Traditionally, nevus counts were collected through manual clinician counts from either in-person examinations or from TBP. This process is however, time consuming, subjective, and achieves poor reproducibility even when completed by experienced dermatologists [
To address the limitations of manual nevus counting, Betz-Stablein et al. developed an AI algorithm to accurately report the total and large nevus count directly from TBP [
Emerging evidence supports that the distribution of nevi across the body surface area may help further assess melanoma risk. The hypothesis of spatial randomness posits that the anatomical distance between adjacent pigmented lesions may differ between melanoma and nevi. Two studies have conducted patient and lesion-level spatial analyses from 3D-TBP and observed whether the spatial distribution was clustered, random, or dispersed. Individuals at high-risk for melanoma were more likely to have a clustered distribution [
Ultraviolet exposure is the primary environmental risk factor for melanoma. Melanocytes exposed to chronic or intermittent sunlight incur a disproportional burden of mutations compared to non-exposed melanocytes. Phenotypic visual photodamage is the strongest correlate to the mutational burden, exceeding even histopathologic markers of photodamage including elastosis and epidermal thinning [
Convolutional neural networks (CNNs) represent a machine learning-based model that can be used to objectively quantify phenotypic photodamage. Creating image-based datasets for dermatology image classification represents a challenging task due to the variability in appearance of the skin surface [
Skin tone is a well-established risk factor for ultraviolet sensitivity and therefore cutaneous malignancy. The clinical estimation of skin tone reflects the variable quantity of chromophores that absorb light within the visible spectrum, including: black-brown eumelanin, red-yellow phaeomelanin, red hemoglobin, red-yellow carotene, and other minor components [
The Fitzpatrick Skin Type is currently the most common clinical tool used to estimate skin tone and skin cancer risk. The tool was first designed to estimate the sensitivity of light skin types (I–IV) to ultraviolet A (UVA) exposure to guide psoralen-UVA therapy [
The Individual Typology Angle (ITA) was devised as an objective and inclusive scale for broad application in dermatology. The ITA is based on the colorimetric system of the Commission Internationale de L’Eclairage (CIE) that quantifies color to the degree of grey between a range of black and white (Luminescence), a red-green component (a*), and a yellow-blue component (b*), all derived from a colorimeter device [
3D-TBP presents the opportunity to capture whole-of-body skin tone as an objective risk factor for skin cancer. Specifically, TBP images contain the constituent color data that can be extracted to calculate the site-specific ITA [
Ephelides, commonly known as freckles, emerge early in life and therefore may be an effective risk factor for younger individuals under the age of 40 years. Ephelides arise after intensive solar exposure in the childhood of genetically predisposed individuals, such as carriers of a Melanocortin 1 Receptor Red Hair Color (MC1R-RHC) allele, and fade with age and in winter. Self-reported ephelides are commonly included in risk stratification models given that their presence is largely independent of other risk factors such as nevus counts and skin tone [
The International Agency for Research on Cancer has called for broad research into melanoma risk factors [
Personalized genomics may capture intrinsic melanoma risk that cannot be captured in a quantifiable cutaneous phenotype. Evidence points to a strong genetic basis for melanoma with heritability estimated to be 58% from the largest relevant twin study that included 2766 monozygotic and 2866 dizygotic twins [
Emerging evidence supports an approach for targeted melanoma surveillance for individuals considered to be at high risk [
The deep imaging phenotype aims to define an automated and objective assessment of personalized melanoma risk factors to guide surveillance requirements. The components of the deep imaging phenotype, such as number, size and distribution of nevi, skin tone, photodamage, freckling, and associated genetic information, may be combined into a holistic risk stratification score to customize surveillance. For example, low-risk individuals may benefit from education on performing self-skin examinations, whereas greater risk scores would indicate a need for regular clinician examination, as well as imaging with TBP and sequential digital dermoscopy. As an understanding of the deep imaging phenotype expands, risk stratification may be tailored towards specific diagnoses, such as lentigo maligna melanoma in older photodamaged individuals or amelanotic melanoma in fairly pigmented or genetically predisposed individuals, and includes the risk for keratinocyte cancers that may be simultaneously detected during skin examination [
Risk stratification using the deep imaging phenotype could facilitate dynamic assessment based on the evolution of cutaneous topology factors with age, and updated with clinical information regarding new diagnoses. This provides opportunity to integrate longitudinal data in risk prediction, while recognizing that different risk factors are relevant at different ages. Phenotypes for freckling may be of greater predictive value in early age before fading, whereas photodamage may have greater relevance in older age after many years of ultraviolet exposure [
Evaluation of the deep imaging phenotype must consider recommendations for individuals determined to be at low risk for melanoma and other cutaneous malignancies. Broad population-based studies will be required to calibrate risk stratification algorithms to a level that constitutes low risk for the specific geographic and demographic characteristics of the region [
Teledermatology services are an increasingly important modality to improve access to specialist dermatology care. Evidence-based validation of these services supports diagnostic and treatment accuracy whilst maintaining cost-effectiveness [
Successful implementation of a deep imaging phenotype protocol for broad population-based or individual risk stratification will be dependent on consumer and clinician trust. A major barrier to this trust is the ‘black box’ problem, referring to the lack of transparency regarding how an algorithm arrived at a diagnostic decision [
Augmented intelligence describes a framework where AI recommendations are provided as a report to be verified by the clinician [
The psychological consequences of risk stratification that labels large numbers of individuals as high or low risk for cutaneous malignancy must be considered. Individuals identified as high risk may be at greater risk of psychological distress and maladaptive coping strategies, whereas low risk individuals may disregard sun-smart behaviors [
Legally, clinicians that opt to integrate AI into clinical practice are likely to assume the liability for its role in clinical decisions. Case law suggests that the clinician is accountable for their use of AI recommendations, although, liability may in some cases extend to the device manufacturer and supplier [
Effective and secure data management is essential for the development and implementation of the deep imaging phenotype for melanoma risk stratification. The Digital Image Communication in Medicine (DICOM) is the standard for the storage, linkage with meta-data, and secure sharing of medical images that is near ubiquitously used in image-producing fields such as radiology and cardiology [
Privacy must be of central importance for storage of dermatology images and clinical data. Dermatology images are unique given the difficulty of de-identifying nudity or personal markings (e.g. tattoos, scars) without compromising the clinical utility of the data. Standardized DICOM confidentiality profiles such as those used in radiology to guide which attributes should be removed from images to ensure privacy, could be adapted for dermatology images such as 3D-TBP [
Risk stratification for melanoma aims to prospectively identify individuals likely to develop a melanoma for targeted screening [
HPS is a shareholder of MoleMap NZ Limited and e-derm consult GmbH and undertakes regular teledermatological reporting for both companies. HPS is a Medical Consultant for Canfield Scientific Inc., Blaze Bioscience Inc., MoleMap Australia Pty Limited, and a Medical Advisor for First Derm. No other authors have conflicts to declare.
The authors declared that no clinical trials were used in the present study.
The authors declared that no experiments on humans or human tissues were performed for the present study.
The authors declared that no informed consent was obtained from the humans, donors or donors’ representatives participating in the study.
The authors declared that no experiments on animals were performed for the present study.
The authors declared that no commercially available immortalised human and animal cell lines were used in the present study.
No funding was reported.
Conceptualization: MJ, CR, CP, HPS, SK. Data curation: SK. Formal analysis: SK. Methodology: SK. Supervision: CP. Writing – original draft: CP, SK. Writing – review and editing: MJ, HPS, CP, SK, CR.
Sam Kahler https://orcid.org/0000-0001-9680-3120
Chantal Rutjes https://orcid.org/0000-0001-7145-4673
Monika Janda https://orcid.org/0000-0002-1728-8085
H. Peter Soyer https://orcid.org/0000-0002-4770-561X
Clare Primiero https://orcid.org/0000-0002-2944-0013
All of the data that support the findings of this study are available in the main text.