The role of artificial intelligence and convolutional neural networks in the management of melanoma: a clinical, pathological, and radiological perspective

Clinical dermatoscopy and pathological slide assessment are essential in the diagnosis and management of patients with cutaneous melanoma. For those presenting with stage IIC disease and beyond, radiological investigations are often considered. The dermatoscopic, whole slide and radiological images used during clinical care are often stored digitally, enabling artificial intelligence (AI) and convolutional neural networks (CNN) to learn, analyse and contribute to the clinical decision-making. A keyword search of the Medline database was performed to assess the progression, capabilities and limitations of AI and CNN and its use in diagnosis and management of cutaneous melanoma. Full-text articles were reviewed if they related to dermatoscopy, pathological slide assessment or radiology. Through analysis of 95 studies, we demonstrate that diagnostic accuracy of AI/CNN can be superior (or at least equal) to clinicians. However, variability in image acquisition, pre-processing, segmentation, and feature extraction remains challenging. With current technological abilities, AI/CNN and clinicians synergistically working together are better than one another in all subspecialty domains relating to cutaneous melanoma. AI has the potential to enhance the diagnostic capabilities of junior dermatology trainees, primary care skin cancer clinicians and general practitioners. For experienced clinicians, AI provides a cost-efficient second opinion. From a pathological and radiological perspective, CNN has the potential to improve workflow efficiency, allowing clinicians to achieve more in a finite amount of time. Until the challenges of AI/CNN are reliably met, however, they can only remain an adjunct to clinical decision-making.

Terahertz in vivo imaging of human skin: Toward detection of abnormal skin pathologies

Terahertz (THz) imaging has long held promise for skin cancer detection but has been hampered by the lack of practical technological implementation. In this article, we introduce a technique for discriminating several skin pathologies using a coherent THz confocal system based on a THz quantum cascade laser. High resolution in vivo THz images (with diffraction limited to the order of 100 μm) of several different lesion types were acquired and compared against one another using the amplitude and phase values. Our system successfully separated pathologies using a combination of phase and amplitude information and their respective surface textures. The large scan field (50 × 40 mm) of the system allows macroscopic visualization of several skin lesions in a single frame. Utilizing THz imaging for dermatological assessment of skin lesions offers substantial additional diagnostic value for clinicians. THz images contain information complementary to the information contained in the conventional digital images.

Practitioner characteristics, diagnostic accuracy metrics and discovering-individual with respect to 637 melanomas documented by 27 general practitioners on the Skin Cancer Audit Research Database

BACKGROUND AND OBJECTIVE

Knowledge of accuracy for melanoma diagnosis and melanoma discovering-individual in primary care is limited. We describe general practitioner (GP) characteristics and analyse defined diagnostic accuracy metrics for GPs in the current study comparing this with a previous study for GPs common to both, and we analyse the individual first discovering each melanoma as a lesion of concern.

METHODS

The characteristics and diagnostic accuracy of 27 Australasian GPs documenting 637 melanomas on the Skin Cancer Audit Research Database (SCARD) in 2013 were described and analysed. The number needed to treat (NNT) and percentage of melanomas that were in situ (percentage in situ) were analysed as surrogates for specificity and sensitivity, respectively. The discovering-individual was analysed according to patient age and sex and lesion Breslow thickness.

RESULTS

The average NNT and percentage in situ were 5.73% and 65.07%, respectively. For 21 GPs in both a 2008-2010 study and the current study, the NNT was 10.78 and 5.56, respectively (p = 0.0037). A consistent trend of decreasing NNT and increasing percentage in situ through increasingly subspecialised GP categories did not reach statistical significance. NNT trended high at ages and sites for which melanoma was rare. While the patient or family member was more likely to discover thick melanomas and melanomas in patients under 40 years, GPs discovered 73.9% of the melanomas as lesions of concern.

CONCLUSIONS

GPs were the discovering-individuals for the majority of melanomas in the current study and their accuracy metrics compared favourably with published figures for dermatologists and GPs.

A reinforcement learning model for AI-based decision support in skin cancer

We investigated whether human preferences hold the potential to improve diagnostic artificial intelligence (AI)-based decision support using skin cancer diagnosis as a use case. We utilized nonuniform rewards and penalties based on expert-generated tables, balancing the benefits and harms of various diagnostic errors, which were applied using reinforcement learning. Compared with supervised learning, the reinforcement learning model improved the sensitivity for melanoma from 61.4% to 79.5% (95% confidence interval (CI): 73.5-85.6%) and for basal cell carcinoma from 79.4% to 87.1% (95% CI: 80.3-93.9%). AI overconfidence was also reduced while simultaneously maintaining accuracy. Reinforcement learning increased the rate of correct diagnoses made by dermatologists by 12.0% (95% CI: 8.8-15.1%) and improved the rate of optimal management decisions from 57.4% to 65.3% (95% CI: 61.7-68.9%). We further demonstrated that the reward-adjusted reinforcement learning model and a threshold-based model outperformed naïve supervised learning in various clinical scenarios. Our findings suggest the potential for incorporating human preferences into image-based diagnostic algorithms.

Dermatoscopic finding of white circles in an invasive pigmented melanoma

Dermatoscopic white circles, seen with both non-polarized and polarized dermatoscopy, are a known clue to actinic keratosis in a flat lesion and invasive squamous cell carcinoma in a raised lesion. We have not discovered a previous published example of this clue in a melanoma. We present a case report of a 70-year-old Australian male with a pigmented superficial spreading melanoma on the face, Breslow thickness 1 mm, with dermatoscopic white circles displayed with both polarized and non-polarized dermatoscopy, and with dermatopathological correlation.

Vascular Diameter as Clue for the Diagnosis of Clinically and/or Dermoscopically Equivocal Pigmented and Non-Pigmented Basal Cell Carcinomas and Nodular Melanomas

Background and objectives: Dermoscopy is a useful tool for the early and non-invasive diagnosis of skin malignancies. Besides many progresses, heavily pigmented and amelanotic skin tumors remain still a challenge. We aimed to investigate by dermoscopy if distinctive morphologic characteristics of vessels may help the diagnosis of equivocal nodular lesions. Materials and Methods: A collage of 16 challenging clinical and dermoscopic images of 8 amelanotic and 8 heavily pigmented nodular melanomas and basal cell carcinomas was sent via e-mail to 8 expert dermoscopists. Results: Dermoscopy improved diagnostic accuracy in 40 cases. Vessels were considered the best clue in 71 cases. Focusing on the diameter of vessels improved diagnosis in 5 cases. Conclusions: vascular diameter in addition to morphology and arrangement may be a useful dermoscopic clue for the differential diagnosis of clinically equivocal nodular malignant tumors.

Dermatoscopic and clinical features of congenital or congenital-type nail matrix nevi: A multicenter prospective cohort study by the International Dermoscopy Society

BACKGROUND

Congenital nail matrix nevi (NMN) are difficult to diagnose because they feature clinical characteristics suggestive of adult subungual melanoma. Nail matrix biopsy is difficult to perform, especially in children.

OBJECTIVE

To describe the initial clinical and dermatoscopic features of NMN appearing at birth (congenital) or after birth but before the age of 5 years (congenital-type).

METHODS

We conducted a prospective, international, and consecutive data collection in 102 hospitals or private medical offices across 30 countries from 2009 to 2019.

RESULTS

There were 69 congenital and 161 congenital-type NMNs. Congenital and congenital-type NMN predominantly displayed an irregular pattern of longitudinal microlines (n = 146, 64%), reminiscent of subungual melanoma in adults. The distal fibrillar ("brush-like") pattern, present in 63 patients (27.8%), was more frequently encountered in congenital NMN than in congenital-type NMN (P = .012). Moreover, congenital NMN more frequently displayed a periungual pigmentation (P = .029) and Hutchinson's sign (P = .027) than did congenital-type NMN.

LIMITATIONS

Lack of systematic biopsy-proven diagnosis and heterogeneity of clinical and dermatoscopic photographs.

CONCLUSION

Congenital and congenital-type NMN showed worrisome clinical and dermatoscopic features similar to those observed in adulthood subungual melanoma. The distal fibrillar ("brush-like") pattern is a suggestive feature of congenital and congenital-type NMN.

Characteristics, treatment and outcomes of 589 melanoma patients documented by 27 general practitioners on the Skin Cancer Audit Research Database

BACKGROUND AND OBJECTIVE

General practitioners manage more melanomas than dermatologists or surgeons in Australia. Previously undescribed, the management and outcomes of melanoma patients treated by multiple Australasian general practitioners are examined.

METHODS

The characteristics, management and outcomes of 589 melanoma patients, managed by 27 Australasian general practitioners and documented on the Skin Cancer Audit Research Database (SCARD), were analysed.

RESULTS

Most patients (58.9%) were males with mean age at diagnosis of 62.7 years (range 18-96), and most melanomas were in situ or thin-invasive. Patients aged under 40 years had fewer melanomas, but a higher proportion (the majority) were invasive, compared with older patients (P < 0.0001). Most (55.9%) melanomas were diagnosed following elliptical excision biopsy, the rate of unintended involved margins being eightfold higher for shave biopsies. Wide re-excision was performed by the treating general practitioner for most (74.9%) melanomas, with thick melanomas preferentially referred to surgeons. The average Breslow thickness of invasive melanomas re-excised by general practitioners was 0.67 mm compared with 1.99 mm for those referred to other specialists (P < 0.0001). Of 205 patients with invasive melanoma, 14 progressed to metastatic disease, 50% of these being associated with nodular melanoma. Nine patients progressed to melanoma-specific death. The 5-year survival rate for patients with invasive melanoma was 95.2% (95% CI: 91.2-98.5%).

CONCLUSIONS

Diagnostic and therapeutic management of a series of melanoma patients by Australasian general practitioners were closely aligned with current guidelines and 5-year survival with respect to invasive melanoma was at least as favourable as national population-based metrics.

Characteristics of 637 melanomas documented by 27 general practitioners on the Skin Cancer Audit Research Database

BACKGROUND AND OBJECTIVE

Most melanomas (including melanomas in situ), in Australasia, are treated by general practitioners (GPs). Previously undescribed, the characteristics of a series of melanomas treated by multiple GPs are examined.

PATIENTS AND METHODS

Six hundred and thirty-seven melanomas treated by 27 Australasian GPs during 2013 and documented on the Skin Cancer Audit Research Database (SCARD) were analysed by anatomical site, subtype, Breslow thickness, diameter, associated naevi and linked adverse outcomes.

RESULTS

Most melanomas (59.7%) were on males, mean age at diagnosis being 62.7 years (range 18-96). Most (65.0%) were in situ, with a high incidence of lentiginous melanoma (LM) (38.8%) and 32% were naevus associated. Most LM (86.4%) were in situ, compared to 55% of superficial spreading melanoma (SSM) (P < 0.0001). There was male predominance on the head, neck and trunk and female predominance on extremities. There was no significant association between Breslow thickness and diameter, with small melanomas as likely to be thick as large melanomas, and melanomas ≤3 mm diameter, on average, more likely to be invasive than larger melanomas. There was a positive correlation between age and both melanoma diameter and Breslow thickness. Seven cases progressed to melanoma-specific death: Five nodular melanoma (NM) and two SSM, one of which was thin (Breslow thickness 0.5 mm).

CONCLUSIONS

A large series of melanomas treated by Australasian GPs were predominantly in situ, with a high proportion of LM subtype. With implications for GP training, NM linked to death was over-represented and there was a novel finding that older patients had larger diameter melanomas.

Dermatoscopic findings and dermatopathological correlates in clinical variants of actinic keratosis, Bowen's disease, keratoacanthoma, and squamous cell carcinoma

Non-melanoma skin cancer (NMSC), predominantly squamous cell carcinoma (SCC) and basal cell carcinoma, is increasing worldwide. Dermatoscopy, which is one of the non-invasive diagnostic techniques, is important for early diagnosis of NMSC. In this study we aimed to determine dermatoscopic features of keratinocyte derived tumors including actinic keratosis (AK), Bowen's disease (BD), keratoacanthoma (KA), and SCC and correlate the dermatoscopic findings with pathology. A total of 242 lesions from 169 patients were included in the study and dermatoscopic and dermatopathological findings of the lesions were retrospectively studied. Revised pattern analysis was used for the dermatoscopic evaluation. Among 242 lesions, 145 were clinically flat (86 AK, 30 BD, and 29 SCC). Presence of vessels, ulceration, fiber sign, keratin mass, and blood spots decreased the probability of a lesion being AK. When the differential diagnosis was considered between KA and SCC vs AK and BD; vessel presence, ulceration, fiber sign, blood spots, white structureless, keratin, and centred vessels favored the diagnosis of KA and SCC. Our results may contribute to the determination of the lesions to be biopsied in patients with multiple AK on chronically sun damaged skin. In non-pigmented lesions when a final diagnosis cannot be established, knowledge of dermatopathologic and dermatoscopic correlation may significantly assist interpretation of dermatoscopic patterns and clues.

Skin lesions of face and scalp - Classification by a market-approved convolutional neural network in comparison with 64 dermatologists

BACKGROUND

The clinical differentiation of face and scalp lesions (FSLs) is challenging even for trained dermatologists. Studies comparing the diagnostic performance of a convolutional neural network (CNN) with dermatologists in FSL are lacking.

METHODS

A market-approved CNN (Moleanalyzer-Pro, FotoFinder Systems) was used for binary classifications of 100 dermoscopic images of FSL. The same lesions were used in a two-level reader study including 64 dermatologists (level I: dermoscopy only; level II: dermoscopy, clinical close-up images, textual information). Primary endpoints were the CNN's sensitivity and specificity in comparison with the dermatologists' management decisions in level II. Generalizability of the CNN results was tested by using four additional external data sets.

RESULTS

The CNN's sensitivity, specificity and ROC AUC were 96.2% [87.0%-98.9%], 68.8% [54.7%-80.1%] and 0.929 [0.880-0.978], respectively. In level II, the dermatologists' management decisions showed a mean sensitivity of 84.2% [82.2%-86.2%] and specificity of 69.4% [66.0%-72.8%]. When fixing the CNN's specificity at the dermatologists' mean specificity (69.4%), the CNN's sensitivity (96.2% [87.0%-98.9%]) was significantly higher than that of dermatologists (84.2% [82.2%-86.2%]; p < 0.001). Dermatologists of all training levels were outperformed by the CNN (all p < 0.001). In confirmation, the CNN's accuracy (83.0%) was significantly higher than dermatologists' accuracies in level II management decisions (all p < 0.001). The CNN's performance was largely confirmed in three additional external data sets but particularly showed a reduced specificity in one Australian data set including FSL on severely sun-damaged skin.

CONCLUSIONS

When applied as an assistant system, the CNN's higher sensitivity at an equivalent specificity may result in an improved early detection of face and scalp skin cancers.

Dermatoscopy of combined blue nevi: a multicentre study of the International Dermoscopy Society

BACKGROUND

Combined blue nevi (CBN) may mimic melanoma and are relatively often biopsied for diagnostic reasons.

OBJECTIVE

To better characterize CBN and to compare it with melanoma.

METHODS

We collected clinical and dermatoscopic images of 111 histologically confirmed CBN and contrasted their dermatoscopic characteristics with 132 partly blue coloured melanomas. Furthermore, we compared the accuracy of human experts using pattern analysis with a computer algorithm based on deep learning.

RESULTS

Combined blue nevi are usually flat or slightly elevated and, in comparison with melanoma, more frequent on the head and neck. Dermatoscopically, they are typified by a blue structureless part in combination with either brown clods (n = 52, 46.8%), lines (n = 28, 25.2%) or skin-coloured or brown structureless areas (n = 31, 27.9%). In contrast with melanoma, the blue part of CBN is more often well defined (18.9% vs. 4.5%, P < 0.001) and more often located in the centre (22.5% vs. 5.3%, P < 0.001). Melanomas are more often chaotic (OR: 28.7, 95% CI: 14.8-55.7, P < 0.001), have at least one melanoma clue (OR: 10.8, 95% CI: 5.2-22.2 P < 0.001) in particular white lines (OR: 37.1, 95% CI: 13.4-102.9, P < 0.001). Using simplified pattern analysis (chaos and clues), two raters reached sensitivities of 93.9% (95% CI: 88.4-97.3%) and 92.4% (95% CI: 86.5-96.3%) at corresponding specificities of 59.5% (95% CI: 49.7-68.7%) and 65.8% (95% CI: 56.2-74.5%). The human accuracy with pattern analysis was on par with a state-of-the-art computer algorithm based on deep learning that achieved an area under the curve of (0.92, 95% CI: 0.87-0.96) and a specificity of 85.3% (95% CI: 76.5-91.7%) at a given sensitivity of 83.6% (95% CI: 72.5-91.5%).

CONCLUSION

CBN usually lack melanoma clues, in particular white lines. The accuracy of pattern analysis for combined nevi is acceptable, and histopathologic confirmation may not be necessary in exemplary cases.

Dermatoscopic features of pigmented intraepidermal carcinoma on the head and neck

BACKGROUND AND OBJECTIVE

Pigmented intraepidermal carcinoma is characterized by dermatoscopic dots and structureless areas, including dots in linear arrangement and by coiled vessels. There are no studies describing the dermatoscopic features of pigmented intraepidermal carcinoma on the head and neck. We aim to characterize the clinical and dermatoscopic appearance of this entity.

PATIENTS AND METHODS

We retrospectively analyzed 79 cases of pigmented intraepidermal carcinoma on the head and neck.

RESULTS

Pigmented intraepidermal carcinoma on the head and neck was characterized dermatoscopically by multiple colors (98.7 %, n = 78), pigmented circles (48.1 %, n = 38), white circles (17.7 %, n = 14), angulated lines (41.8 %, n = 33) and structureless areas (86.1 %, n = 68). Dots in linear arrangement were present in 13.9 % (n = 11). Coiled vessels were present in 7.6 % (n = 6), the dominant vessel type being prominent serpentine vessels (29.2 %, n = 23), thicker and/or redder in color than surrounding vessels, most being in the angular arrangement of the dermal plexus (24.1 %, n = 19).

CONCLUSIONS

Pigmented intraepidermal carcinoma on the head and neck differs from current published descriptions of pigmented intraepidermal carcinoma, reaching statistical significance with a lower incidence of coiled vessels and a higher incidence of pigmented circles, with evident similarities to pigmented actinic keratosis at that location.

Training Primary Care Physicians in Dermoscopy for Skin Cancer Detection: a Scoping Review

In many countries, patients with concerning skin lesions will first consult a primary care physician (PCP). Dermoscopy has an evidence base supporting its use in primary care for skin cancer detection, but need for training has been cited as a key barrier to its use. How PCPs train to use dermoscopy is unclear. A scoping literature review was carried out to examine what is known from the published literature about PCP training in dermoscopy. The methodological steps taken in this review followed those described by Arksey and O'Malley, as revised by Levac et al. Four electronic databases were searched for evidence published up to June 2018. Sixteen articles were identified for analysis, all published since 2000. Ten training programs were identified all of which addressed dermoscopy of pigmented skin lesions, among other topics. Ten articles reported on a range of outcomes measured after training and showed generally positive results in terms of improved diagnostic performance, although no meta-analysis was conducted. However, it was unclear whether trained PCPs continued to use dermoscopy after training. Observational questionnaire data revealed that many PCPs use dermoscopy in practice without any formal training. The literature generally supports the use of dermoscopy by PCPs, but it is unclear whether current training leads to long-term change in PCPs' use of dermoscopy in clinical practice. Understanding this problem, as well as exploring PCPs' training needs, is essential to develop training programs that will facilitate the uptake and use of dermoscopy in primary care.

Clinical evolution of Spitz nevi

Nevus Spitz is a benign melanocytic proliferation, first described in 1948 by Sophie Spitz as a childhood melanoma. Initially, it was described as an erythematous papule or node, but further studies of the Spitz nevus proved that in 71-92% cases it is a pigmented formation. This pigmentation is often quite intense due to the rapid growth of the formation, which leads to the need for differential diagnosis with skin melanoma. After all, dermatoscopy can be used for this purpose and, when applying this research method, typically a pattern of an exploding star formed by streaks of linear pigmentation and symmetrically located pigment globules placed in the peripheral zone can be revealed. In case of non-pigmented Spitz nevus, spot vessels and reticular depigmentation are visualized. Both pigmented and non-pigmented forms of Spitz nevus in the process of evolution can regress partially or completely. Several clinical cases of different types of spitzoids, both typical and atypical, based on the non-clinical, dermatoscopic and histological diversity of the Spitz nevi, have been demonstrated in the article. Their macroscopic and dermatoscopic features as well as probable signs of dynamic changes are indicated in order to facilitate their recognition by other specialists.

Human-computer collaboration for skin cancer recognition

The rapid increase in telemedicine coupled with recent advances in diagnostic artificial intelligence (AI) create the imperative to consider the opportunities and risks of inserting AI-based support into new paradigms of care. Here we build on recent achievements in the accuracy of image-based AI for skin cancer diagnosis to address the effects of varied representations of AI-based support across different levels of clinical expertise and multiple clinical workflows. We find that good quality AI-based support of clinical decision-making improves diagnostic accuracy over that of either AI or physicians alone, and that the least experienced clinicians gain the most from AI-based support. We further find that AI-based multiclass probabilities outperformed content-based image retrieval (CBIR) representations of AI in the mobile technology environment, and AI-based support had utility in simulations of second opinions and of telemedicine triage. In addition to demonstrating the potential benefits associated with good quality AI in the hands of non-expert clinicians, we find that faulty AI can mislead the entire spectrum of clinicians, including experts. Lastly, we show that insights derived from AI class-activation maps can inform improvements in human diagnosis. Together, our approach and findings offer a framework for future studies across the spectrum of image-based diagnostics to improve human-computer collaboration in clinical practice.

Sclerodermiform basal cell carcinomas vs. other histotypes: analysis of specific demographic, clinical and dermatoscopic features

BACKGROUND

Among the various types of basal cell carcinoma, the sclerodermiform variant has a high risk of recurrence and local invasiveness. A systematic description of the dermatoscopic features associated with specific body localization is lacking.

OBJECTIVES

To describe the clinical and dermoscopic features of sclerodermiform basal cell carcinoma (BCC) according to localization in the body confronting with superficial and nodular types.

METHODS

Clinical and dermoscopic images of sclerodermiform, nodular and superficial BCCs were retrospectively evaluated to study the location in the various body districts, maximum diameter, clinical appearance of the lesion, features of edges and presence or absence of specific dermatoscopic criteria of BCCs.

RESULTS

We examined 291 histopathologically proven BCCs showing that in nodular BCCs, classical arborizing vessels were more frequently found in the body macro-area (trunk and limbs; n = 46, 97.9%) than in the head/neck area (n = 43, 82.7%); within sclerodermiform BCCs, short arborizing vessels were found more frequently in the head/neck district (n = 35, 49.3%) than in the body (n = 6, 23.1%; P-value 0.02); within nodular BCCs, multiple blue-grey dots and globules were more frequently found on the trunk (n = 23, 48.9%) than in the head/neck district (n = 12, 23.1%; P-value 0.01). In sclerodermiform BCCs, ulceration was found more frequently in the head/neck district (n = 38, 53.5%) than in the body (n = 4, 15.4%; P-value > 0.01), and in superficial BCCs, ulceration was found more frequently in the head/neck district (n = 5, 38.5%) than in the body (n = 8, 9.8%; P-value 0.02).

CONCLUSION

Our study shows that superficial BCC are found frequently in the head/neck district dermoscopically characterized by ulceration and arborizing vessels; nodular BCCs are more frequently found in the body than in the head/neck district, and the dermoscopic pattern is characterized by the combination of three features: (i) classical arborizing vessels, (ii) multiple blue-grey dots and (iii) globules. Instead, sclerodermiform BCC is preferentially located in areas at high-moderate risk of recurrence; if pink-white areas and/or fine arborizing vessels are seen, clinicians should consider this diagnosis. Furthermore, location-specific dermatoscopic criteria have been described.

[Depression, anxiety, delirium and desire to die in palliative care : Recommendations of the S3 guideline on palliative care for patients with incurable cancer]

BACKGROUND

The aim of palliative care is to optimize the quality of life of patients with incurable advanced diseases. Adequate psychotherapeutic and psychiatric care is essential in this context.

OBJECTIVE

This article presents the recommendations of the S3 guideline on palliative care for patients with incurable cancer with regard to psychotherapeutic and psychiatric contents.

MATERIAL AND METHODS

The guideline was developed under the leadership of the German Society for Palliative Medicine (DGP) within the methodological framework of the German Guideline Program in Oncology. Systematic literature reviews were carried out to identify relevant publications in the databases Medline, Cochrane Library, PsycInfo and Embase. Based on the publications included and clinical experience, representatives of 61 professional associations developed and agreed on evidence-based and consensus-based recommendations.

RESULTS

Out of the total of 15 chapters in the guidelines, four have a special reference to psychiatry or psychotherapy; they cover the topics depression, anxiety, delirium in the dying phase and dealing with the desire to die. These chapters contain a total of 71 recommendations, almost one third of which are evidence-based. In view of the regularly undetected psychological symptoms in patients with incurable cancer, an early assessment is recommended. Optimal control of physical symptoms and support in social and existential matters are general measures that should be provided in addition to non-pharmacological and pharmacological procedures.

CONCLUSION

The guideline on palliative care deals with important mental issues that should be considered by all disciplines and professions. The need for research in palliative care remains high.

Analysis of Collective Human Intelligence for Diagnosis of Pigmented Skin Lesions Harnessed by Gamification Via a Web-Based Training Platform: Simulation Reader Study

Background

The diagnosis of pigmented skin lesion is error prone and requires domain-specific expertise, which is not readily available in many parts of the world. Collective intelligence could potentially decrease the error rates of nonexperts.

Objective

The aim of this study was to evaluate the feasibility and impact of collective intelligence for the detection of skin cancer.

Methods

We created a gamified study platform on a stack of established Web technologies and presented 4216 dermatoscopic images of the most common benign and malignant pigmented skin lesions to 1245 human raters with different levels of experience. Raters were recruited via scientific meetings, mailing lists, and social media posts. Education was self-declared, and domain-specific experience was tested by screening tests. In the target test, the readers had to assign 30 dermatoscopic images to 1 of the 7 disease categories. The readers could repeat the test with different lesions at their own discretion. Collective human intelligence was achieved by sampling answers from multiple readers. The disease category with most votes was regarded as the collective vote per image.

Results

We collected 111,019 single ratings, with a mean of 25.2 (SD 18.5) ratings per image. As single raters, nonexperts achieved a lower mean accuracy (58.6%) than experts (68.4%; mean difference=−9.4%; 95% CI −10.74% to −8.1%; P<.001). Collectives of nonexperts achieved higher accuracies than single raters, and the improvement increased with the size of the collective. A collective of 4 nonexperts surpassed single nonexperts in accuracy by 6.3% (95% CI 6.1% to 6.6%; P<.001). The accuracy of a collective of 8 nonexperts was 9.7% higher (95% CI 9.5% to 10.29%; P<.001) than that of single nonexperts, an improvement similar to single experts (P=.73). The sensitivity for malignant images increased for nonexperts (66.3% to 77.6%) and experts (64.6% to 79.4%) for answers given faster than the intrarater mean.

Conclusions

A high number of raters can be attracted by elements of gamification and Web-based marketing via mailing lists and social media. Nonexperts increase their accuracy to expert level when acting as a collective, and faster answers correspond to higher accuracy. This information could be useful in a teledermatology setting.

Dermatoscopic and Mucoscopic Features of Lesions in Patients with Behcet's Disease

OBJECTIVE

Behcet's disease (BD), as a vasculitis, can affect small and large vessels. As dermatoscopy has been shown to improve the accuracy in diagnosis of various skin lesions especially vascular patterns, we set this study to find if there is any characteristic pattern in the dermatoscopy of Behcet's mucocutaneous lesions.

METHODS

This prospective cross-sectional observational study designed to evaluate dermatoscopic features of Behcet's mucocutaneous lesions. Fifty six consecutive patients presenting at the outpatient clinic of the BD Research Unit were included. If present, for each patient one oral, one skin and one genital lesion were evaluated by dermatoscopy. When indicated, pathergy test was performed according to a standard protocol and the results were evaluated by dermatoscopy.

RESULTS

A total of 40 oral, 8 genital, 14 skin lesions and 14 pathergy tests were evaluated by dermatoscopy. While vascular component was the most prominent feature in oral aphthae, this component was less prominent in genital lesions. Dot vessels were the most common form of vessels in both oral and skin lesions. All the oral lesions were characterized by a central white structureless area. Skin lesions were characterized by a red structureless background. In pathergy tests, negative pricks showed absence of specific features while positive pricks were characterized by a structureless background in pink, purple or red. No obvious vascular component was detected in any of the pricks.

CONCLUSION

It seems that these findings have no specific clues for the diagnosis of BD, but our study is the first study in this field and the findings may give way to further investigations.

Expert-Level Diagnosis of Nonpigmented Skin Cancer by Combined Convolutional Neural Networks

Importance

Convolutional neural networks (CNNs) achieve expert-level accuracy in the diagnosis of pigmented melanocytic lesions. However, the most common types of skin cancer are nonpigmented and nonmelanocytic, and are more difficult to diagnose.

Objective

To compare the accuracy of a CNN-based classifier with that of physicians with different levels of experience.

Design, Setting, and Participants

A CNN-based classification model was trained on 7895 dermoscopic and 5829 close-up images of lesions excised at a primary skin cancer clinic between January 1, 2008, and July 13, 2017, for a combined evaluation of both imaging methods. The combined CNN (cCNN) was tested on a set of 2072 unknown cases and compared with results from 95 human raters who were medical personnel, including 62 board-certified dermatologists, with different experience in dermoscopy.

Main Outcomes and Measures

The proportions of correct specific diagnoses and the accuracy to differentiate between benign and malignant lesions measured as an area under the receiver operating characteristic curve served as main outcome measures.

Results

Among 95 human raters (51.6% female; mean age, 43.4 years; 95% CI, 41.0-45.7 years), the participants were divided into 3 groups (according to years of experience with dermoscopy): beginner raters (<3 years), intermediate raters (3-10 years), or expert raters (>10 years). The area under the receiver operating characteristic curve of the trained cCNN was higher than human ratings (0.742; 95% CI, 0.729-0.755 vs 0.695; 95% CI, 0.676-0.713; P < .001). The specificity was fixed at the mean level of human raters (51.3%), and therefore the sensitivity of the cCNN (80.5%; 95% CI, 79.0%-82.1%) was higher than that of human raters (77.6%; 95% CI, 74.7%-80.5%). The cCNN achieved a higher percentage of correct specific diagnoses compared with human raters (37.6%; 95% CI, 36.6%-38.4% vs 33.5%; 95% CI, 31.5%-35.6%; P = .001) but not compared with experts (37.3%; 95% CI, 35.7%-38.8% vs 40.0%; 95% CI, 37.0%-43.0%; P = .18).

Conclusions and Relevance

Neural networks are able to classify dermoscopic and close-up images of nonpigmented lesions as accurately as human experts in an experimental setting.

Comparison of the accuracy of human readers versus machine-learning algorithms for pigmented skin lesion classification: an open, web-based, international, diagnostic study

BACKGROUND

Whether machine-learning algorithms can diagnose all pigmented skin lesions as accurately as human experts is unclear. The aim of this study was to compare the diagnostic accuracy of state-of-the-art machine-learning algorithms with human readers for all clinically relevant types of benign and malignant pigmented skin lesions.

METHODS

For this open, web-based, international, diagnostic study, human readers were asked to diagnose dermatoscopic images selected randomly in 30-image batches from a test set of 1511 images. The diagnoses from human readers were compared with those of 139 algorithms created by 77 machine-learning labs, who participated in the International Skin Imaging Collaboration 2018 challenge and received a training set of 10 015 images in advance. The ground truth of each lesion fell into one of seven predefined disease categories: intraepithelial carcinoma including actinic keratoses and Bowen's disease; basal cell carcinoma; benign keratinocytic lesions including solar lentigo, seborrheic keratosis and lichen planus-like keratosis; dermatofibroma; melanoma; melanocytic nevus; and vascular lesions. The two main outcomes were the differences in the number of correct specific diagnoses per batch between all human readers and the top three algorithms, and between human experts and the top three algorithms.

FINDINGS

Between Aug 4, 2018, and Sept 30, 2018, 511 human readers from 63 countries had at least one attempt in the reader study. 283 (55·4%) of 511 human readers were board-certified dermatologists, 118 (23·1%) were dermatology residents, and 83 (16·2%) were general practitioners. When comparing all human readers with all machine-learning algorithms, the algorithms achieved a mean of 2·01 (95% CI 1·97 to 2·04; p<0·0001) more correct diagnoses (17·91 [SD 3·42] vs 19·92 [4·27]). 27 human experts with more than 10 years of experience achieved a mean of 18·78 (SD 3·15) correct answers, compared with 25·43 (1·95) correct answers for the top three machine algorithms (mean difference 6·65, 95% CI 6·06-7·25; p<0·0001). The difference between human experts and the top three algorithms was significantly lower for images in the test set that were collected from sources not included in the training set (human underperformance of 11·4%, 95% CI 9·9-12·9 vs 3·6%, 0·8-6·3; p<0·0001).

INTERPRETATION

State-of-the-art machine-learning classifiers outperformed human experts in the diagnosis of pigmented skin lesions and should have a more important role in clinical practice. However, a possible limitation of these algorithms is their decreased performance for out-of-distribution images, which should be addressed in future research.

FUNDING

None.

Black salve in a nutshell

Background

Black salve is an alternative therapy increasingly chosen by patients to selfmanage their skin lesions. It is promoted as an effective, safe and natural skin cancer treatment, but such claims are not evidence-based, and serious complications have been reported. The sale of black salve in Australia is illegal.

Objective

The aim of this article is to educate general practitioners (GPs) about black salve, enabling informed discussion with patients considering using black salve. An overview of the scientific literature is presented.

Discussion

Case reports have described significant morbidity and even mortality associated with the use of black salve. Despite this, black salve is readily accessible to the public online; a simple internet search yields multiple links to websites endorsing black salve as an effective natural skin cancer remedy. As GPs are often called on in the initial presentation of skin complaints, they are well positioned to ask patients about their use of black salve and educate them about its risks.

Dermoscopy Use in Primary Care: A Scoping Review

Background

Patients in many countries with new or changing skin lesions will first consult a primary care physician, often called a general practitioner (GP). With the dramatic rise in melanoma incidence over recent decades, dermoscopy offers a tool with an evidence base supporting its use in skin lesion assessment. How GPs use dermoscopy is unclear.

Objectives

A scoping literature review was carried out to examine the current state of published evidence about dermoscopy use in primary care.

Methods

The methodological steps taken in this review followed those developed by Arksey and O'Malley, as revised by Levac and colleagues. Four electronic databases were searched for evidence published up to January 2018 describing the use of dermoscopy in a generalist primary care setting. Seven articles were identified for analysis.

Results

All included articles have been published since 2007. Most were questionnaire studies and revealed that generally a small minority of GPs use dermoscopy, although some jurisdictions such as Australia report greater use. Dermoscopy is generally used only for the assessment of pigmented skin lesions, but is not used consistently. Several perceived barriers to dermoscopy use, including the need for training, have been reported.

Conclusions

There is a paucity of data on dermoscopy use among GPs, and diversity in questionnaire items prevents comparison between jurisdictions. Perceived barriers to dermoscopy use require more in-depth exploration, potentially including qualitative data, to evaluate them more fully. Understanding these factors, including how GPs train in dermoscopy, will be crucial in widening dermoscopy use in primary care.

[Guideline conform diagnostics for dysphagia : A representative survey of speech therapists at certified stroke units in Germany]

BACKGROUND

Almost 260,000 people in Germany suffer from a stroke each year. As a consequence, for more than 60% this leads to dysphagia. In order to prevent secondary diseases, such as pneumonia, malnutrition and dehydration, a differentiated diagnosis by a multiprofessional team in a stroke unit is required. The guidelines in 2015 for diagnosing neurologic dysphagia by the German Society of Neurology recommend a detailed anamnesis, a standardized screening, a clinical swallowing examination and additional instrumental diagnostics.

OBJECTIVE

This study examined whether dysphagia is diagnosed by speech therapists at certified stroke units according to the recommended guidelines.

MATERIAL AND METHODS

An online questionnaire was compiled and sent to 1 speech therapist at each of the 195 certified stoke units and 112 participants responded to the questionnaire. The questionnaire consisted of questions about anamnesis, clinical swallowing diagnostics and the instrumental diagnostics. Of the speech therapists working on a stroke unit 57% participated in this study.

RESULTS

The results show that 50% of the participants elaborated a detailed and differentiated anamnesis, 64% used a standardized screening (Daniels test) and 66% implemented a guideline conform swallowing test. As technical instruments, 35% of the respondents used video fluoroscopy and 71% of the respondents a fiber endoscopy.

CONCLUSION

The implementation of a detailed and differentiated anamnesis, standardized screening, and a clinical swallowing examination with testing of different food consistencies suggests a high quality of the dysphagia diagnostics at stroke units in Germany. The increasing availability of technical instruments, especially fiber endoscopy, substantiates this view.

Dermoscopy features of atypical fibroxanthoma: A multicenter study of the International Dermoscopy Society

BACKGROUND/OBJECTIVES

Little is known about the dermoscopic features of atypical fibroxanthoma.

METHODS

This was a case-control study. Atypical fibroxanthoma lesions were compared with a control group with non-melanoma skin cancer.

RESULTS

Altogether 40 atypical fibroxanthoma were collected. Most developed in men (93%), appearing mainly as nodular (63%), amelanotic (93%) and ulcerated (78%) lesions. Most lesions were located on the scalp (55%) and the ears (13%). Dermoscopically, most atypical fibroxanthoma displayed red (83%) and white (70%) structureless areas and irregular linear vessels (43%). A series of features achieved statistical significance when comparing atypical fibroxanthoma with non-melanoma skin cancer. The presence of red and white structureless areas and white lines, and the absence of yellowish-white opaque scales, hairpin vessels and arborising vessels were predictive of atypical fibroxanthoma in univariate analysis. However, when squamous cell carcinoma was excluded from the analysis, none of the criteria achieved statistical significance. When basal cell carcinoma was excluded, three variables achieved statistical significance in predicting atypical fibroxanthoma: red, structureless areas, the absence of opaque yellowish-white scales and absence of white circles.

CONCLUSIONS

Atypical fibroxanthomas seem to be barely distinguishable from basal cell carcinoma dermoscopically, but they are more easily distinguishable from a well to moderately differentiated squamous cell carcinoma. A histopathological examination is needed for the final diagnosis.

Accuracy of dermatoscopy for the diagnosis of nonpigmented cancers of the skin

BACKGROUND

Nonpigmented skin cancer is common, and diagnosis with the unaided eye is error prone.

OBJECTIVE

To investigate whether dermatoscopy improves the diagnostic accuracy for nonpigmented (amelanotic) cutaneous neoplasms.

METHODS

We collected a sample of 2072 benign and malignant neoplastic lesions and inflammatory conditions and presented close-up images taken with and without dermatoscopy to 95 examiners with different levels of experience.

RESULTS

The area under the curve was significantly higher with than without dermatoscopy (0.68 vs 0.64, P < .001). Among 51 possible diagnoses, the correct diagnosis was selected in 33.1% of cases with and 26.4% of cases without dermatoscopy (P < .001). For experts, the frequencies of correct specific diagnoses of a malignant lesion improved from 40.2% without to 51.3% with dermatoscopy. For all malignant neoplasms combined, the frequencies of appropriate management strategies increased from 78.1% without to 82.5% with dermatoscopy.

LIMITATIONS

The study deviated from a real-life clinical setting and was potentially affected by verification and selection bias.

CONCLUSIONS

Dermatoscopy improves the diagnosis and management of nonpigmented skin cancer and should be used as an adjunct to examination with the unaided eye.

Nail apparatus melanoma initially diagnosed as nail matrix blue nevus: a case report with dermatoscopy and dermatopathology

We present a case of nail apparatus melanoma in a 50-year-old woman presenting as new and changing longitudinal melanonychia of the right thumb. Very heavy melanin pigmentation involving both the epidermis and dermis interfered with dermatopathological assessment, which initially leads to a diagnosis of nail matrix blue nevus. After consultation with a specialist multidisciplinary clinic the diagnosis was revised to invasive melanoma, a diagnosis consistent with the clinical and dermatoscopic assessment.

Basosquamous carcinoma: Dermoscopic clues to diagnosis

Basosquamous carcinoma (BSC) is a rare skin cancer which has areas of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) and a transition zone between them. However, dermoscopic features of BSC are not well described in the published work, except one study. The aim of the present study was to better identify and clarify the dermoscopic findings of BSC in the largest group of patients in the published work and to describe its dermoscopic features according to histopathologically BCC-dominant, SCC-dominant and intermediate categories. Dermoscopic features of 36 histopathologically proven BSC and their dermatopathological correlates were retrospectively analyzed. Dermoscopic features were evaluated by pattern analysis. Keratin mass (91.7%) was the most common dermoscopic feature. Surface scaling (77.8%), ulceration (69.4%), white structureless areas (69.4%), white clods (66.7%) and blood spots on keratin mass (66.7%) were the other frequent findings. Polymorphous vascular pattern consisting of various combinations of branched, serpentine, straight, coiled or looped vessels were detected in 61% of the lesions. BSC has BCC-dominant vascular features together with otherwise SCC-dominant morphology, the common pattern seen in BSC lesions being BCC-dominant polymorphous or monomorphous vasculature, together with dermoscopic findings of keratinization. White circles, known to be a valuable clue to SCC and keratoacanthoma, were present at the same magnitude in BSC in our study. The observed histological correlation of eosinophilic keratin overlying the epithelium which lined follicular infundibulae in these tumors, provides a plausible new perspective on dermoscopic white circles.

Comparison of PTCH1, COX-2, p53, and Ki-67 protein expression in basal cell carcinomas of nodular and superficial subtypes arising on the head and trunk

BACKGROUND

There is some evidence that basal cell carcinomas (BCCs) arising on different anatomic sites and developing to different histological subtypes differ in their pathophysiology. The expression of a number of proteins, including PTCH1, COX-2, p53, and Ki-67, is frequently altered in BCC development.

OBJECTIVES

This study sought to determine whether protein expression differs between BCCs at different anatomic sites and of different histological subtypes.

METHODS

Expression of PTCH1, COX-2, p53, and Ki-67 proteins was compared between: (i) BCCs arising on the head (n = 55) and trunk (n = 53), and (ii) nodular (n = 52) and superficial (n = 43) BCCs. The intensity of immunohistochemistry (IHC) staining (low, moderate, strong, very strong) for PTCH1 and COX-2 proteins was measured and the proportions of p53- and Ki-67-positive cells quantified.

RESULTS

The proportion of cells expressing Ki-67 was higher in tumor tissue than in non-malignant epidermis, whereas the opposite was found for PTCH1. The IHC staining intensity for PTCH1 was substantially greater in truncal BCCs than in BCCs on the head (odds ratio [OR] 3.82, 95% confidence interval [CI] 1.63-8.96). The intensity of staining for PTCH1 was greater for superficial than for nodular BCCs (OR 3.70, 95% CI 1.53-8.97), and superficial BCCs showed a higher proportion of Ki-67-positive cells (OR 5.57, 95% CI 1.66-18.67).

CONCLUSIONS

These differences suggest that the pathophysiology of BCC differs between lesions on the head and trunk and between nodular and superficial subtypes, perhaps indicating differences in their etiology.

Trichilemmoma in continuity with pigmented basal cell carcinoma; with dermatoscopy and dermatopathology

A case of trichilemmoma in continuity with a pigmented basal cell carcinoma is presented with dermatoscopy and dermatopathology. The distinction between the two lesions was evident dermatoscopically and was confirmed dermatopathologically. While trichilemmoma has been reported in association with basal cell carcinoma and dermatoscopy images of four previous cases of trichilemmoma have been published, no previous dermatoscopy image has been published of trichilemmoma associated with basal cell carcinoma.

Basal cell carcinomas on sun-protected vs. sun-exposed body sites: a comparison of phenotypic and environmental risk factors

BACKGROUND

Basal cell carcinoma (BCC) is the most commonly diagnosed cancer in White populations. There are indications that risk factors for BCC may differ according to the anatomic site of the tumour but this is not well understood.

PURPOSE

To compare phenotypic and environmental risk factors for BCCs arising on sun-protected sites with that of those on sun-exposed sites.

METHODS

We conducted a case-case study in which people who had been diagnosed with incident BCC were recruited between February 2012 and September 2013 in Brisbane, Australia.

RESULTS

Fair skin (OR: 4.50; 95% CI: 1.22, 16.59), having more than 15 lesions frozen/burnt off compared to less than 5 (OR: 5.68; 95% CI: 1.78, 18.08) and severe acne (OR: 5.25; 95% CI: 1.34, 20.56) were associated with increased risk of BCC on sun-protected sites. The presence of more than 5 nevi on the body was associated with decreased risk (OR: 0.28; 95% CI: 0.11, 0.71).

CONCLUSIONS

BCCs on sun-protected sites arise as a result of excessive sun exposure, most likely combined with phenotypic susceptibility. The strong negative association with nevi also suggests that there are constitutional factors that underlie the propensity for BCCs to arise on these body sites.

Clinical and dermoscopic characteristics of melanomas on nonfacial chronically sun-damaged skin

BACKGROUND

Melanomas on chronically sun-damaged skin (CSDS) can be difficult to identify and often manifest morphologic features that overlap with benign lesions.

OBJECTIVE

We describe and analyze the clinical and dermoscopic characteristics of melanomas on nonfacial CSDS.

METHODS

Melanoma cases on nonfacial CSDS were retrospectively identified from the biopsy specimen logs of 6 melanoma clinics. Clinical and dermoscopic images were combined into 1 database. Demographics, clinical, dermoscopic, and histopathologic information were analyzed. Descriptive frequencies were calculated.

RESULTS

One hundred eighty-six cases met the inclusion criteria: 142 melanomas in situ (76%) and 39 invasive (21%; mean thickness, 0.49 mm). Lentigo maligna was the most common histopathologic subtype (n = 76; 40.9%). The most frequent dermoscopic structures were granularity (n = 126; 67.7%) and angulated lines (n = 82; 44%). Vascular structures were more frequent in invasive melanomas (56% vs 12% of in situ melanomas). Most manifested 1 of 3 dermoscopic patterns: patchy peripheral pigmented islands, angulated lines, and tan structureless with granularity pattern.

LIMITATIONS

This was a retrospective study, and evaluators were not blinded to the diagnosis. In addition, interobserver concordance and sensitivity and specificity for dermoscopic structures were not evaluated.

CONCLUSION

Outlier lesions manifesting dermoscopic structures, such as granularity, angulated lines, or vessels and any of the 3 described dermoscopic patterns should raise suspicion for melanoma.

Application of black salve to a thin melanoma that subsequently progressed to metastatic melanoma: a case study

This is a case study of a female patient diagnosed with superficial spreading melanoma who decided to treat the lesion by the application of a preparation known as black salve. Persistence of the melanoma was documented five years later with subsequent evidence of metastatic spread to the regional lymph nodes, lungs, liver, subcutaneous tissues and musculature. A literature search has revealed one other case study of the use of black salve for the treatment of melanoma.