Benign Pigmented Skin Lesions Research Articles

Utilizing Data from Electrical Impedance Spectroscopy Significantly Improves the Decision to Biopsy Pigmented Skin Lesions Beyond Clinical Evaluation and Dermoscopy

Background: Even the most experienced dermatologists may forego a biopsy on as many as one-third of malignant melanomas (MMs). Electrical impedance spectroscopy (EIS) is a noninvasive technology that send a painless, very low voltage electrical current through a pigmented lesion to determine if it is benign or malignant. This study aimed to determine if EIS data can improve the decision to biopsy a pigmented lesion even beyond dermoscopy. Methods: A survey with 49 images of MMs, severe dysplastic nevi (SDNs), and benign pigmented skin lesions (PSLs) was shown to dermatologists at a national conference. They were asked if they would biopsy the lesion after first seeing the clinical image, then again after seeing the dermoscopic image, and again after receiving the EIS score. Results: 151 dermatologists completed the survey. Respondents significantly increased correct biopsy decisions (biopsy MMs and SDNs and forego biopsy of benign PSLs) with the addition of dermoscopy versus clinical image alone for MM (78.5% vs. 56.2%, p<0.01) and SDN (62.7% vs. 43.8%, p<0.01). Participants also demonstrated a statistically significant increase in correct biopsy decisions beyond the dermoscopic evaluation when integrating the EIS score for MM (86.2% vs. 78.9%, p<0.01), SDN (68.1% vs. 62.7%, p<0.05) and benign lesions (58.7% vs. 48.0% vs, p<0.01). Conclusion: EIS was able to further improve the rate of correct biopsy choice for MMs and SDNs even beyond dermoscopic evaluation. While dermoscopy worsened diagnostic accuracy for benign PSLs, EIS results were able to significantly improve decision making for these lesions as well. This study demonstrates the clinical utility of EIS technology for improving melanoma diagnosis.

IMAGE PROCESSING OF SKIN CANCER DETECTION IN MATLAB USING GLCM AND SVM

The incidence of skin cancer is high and rising worldwide, a trend that is likely to continue given the importance of solar ultra-violet as a cause and the modern propensity to indoor lifestyle with sun-seeking holidays. Malignant melanoma is the most deadly form due to its rapid development, invasion, and metastasis cycle. Early diagnosis is paramount as prognosis is greatly improved where the tumour is excised quickly. Many common benign pigmented skin lesions can resemble early melanomas. The primary objective of this work is cancer classification from melanoma images using deep learning model. Keywords: Skin Cancer, K-Means, DRLBP, CNN.

Automatic identification of benign pigmented skin lesions from clinical images using deep convolutional neural network

ObjectiveWe aimed to develop a computer-aided detection (CAD) system for accurate identification of benign pigmented skin lesions (PSLs) from images captured using a digital camera or a smart phone.MethodsWe collected a total of 12,836 clinical images which had been classified and location-labeled for training and validating. Four models were developed and validated; you only look once, v4 (YOLOv4), you only look once, v5 (YOLOv5), single shot multibox detector (SSD) and faster region-based convolutional neural networks (Faster R-CNN). The performance of the models was compared with three trained dermatologists, respectively. The accuracy of the best model was further tested and validated using smartphone-captured images.ResultsThe accuracies of YOLOv4, YOLOv5, SSD and Faster R-CNN were 0.891, 0.929, 0.852 and 0.874, respectively. The precision, sensitivity and specificity of YOLOv5 (the best model) were 0.956, 0.962 and 0.952, respectively. The accuracy of YOLOv5 model for images captured using a smart-phone was 0.905. The CAD based YOLOv5 system can potentially be used in clinical identification of PSLs.ConclusionWe developed and validated a CAD system for automatic identification of benign PSLs using digital images. This approach may be used by non-dermatologists to easily diagnose by taking a photo of skin lesion and guide on management of PSLs.

Discrimination of cancerous from benign pigmented skin lesions based on multispectral autofluorescence lifetime imaging dermoscopy and machine learning.

.SignificanceAccurate early diagnosis of malignant skin lesions is critical in providing adequate and timely treatment; unfortunately, initial clinical evaluation of similar-looking benign and malignant skin lesions can result in missed diagnosis of malignant lesions and unnecessary biopsy of benign ones.AimTo develop and validate a label-free and objective image-guided strategy for the clinical evaluation of suspicious pigmented skin lesions based on multispectral autofluorescence lifetime imaging (maFLIM) dermoscopy.ApproachWe tested the hypothesis that maFLIM-derived autofluorescence global features can be used in machine-learning (ML) models to discriminate malignant from benign pigmented skin lesions. Clinical widefield maFLIM dermoscopy imaging of 41 benign and 19 malignant pigmented skin lesions from 30 patients were acquired prior to tissue biopsy sampling. Three different pools of global image-level maFLIM features were extracted: multispectral intensity, time-domain biexponential, and frequency-domain phasor features. The classification potential of each feature pool to discriminate benign versus malignant pigmented skin lesions was evaluated by training quadratic discriminant analysis (QDA) classification models and applying a leave-one-patient-out cross-validation strategy.ResultsClassification performance estimates obtained after unbiased feature selection were as follows: 68% sensitivity and 80% specificity with the phasor feature pool, 84% sensitivity, and 71% specificity with the biexponential feature pool, and 84% sensitivity and 32% specificity with the intensity feature pool. Ensemble combinations of QDA models trained with phasor and biexponential features yielded sensitivity of 84% and specificity of 90%, outperforming all other models considered.ConclusionsSimple classification ML models based on time-resolved (biexponential and phasor) autofluorescence global features extracted from maFLIM dermoscopy images have the potential to provide objective discrimination of malignant from benign pigmented lesions. ML-assisted maFLIM dermoscopy could potentially assist with the clinical evaluation of suspicious lesions and the identification of those patients benefiting the most from biopsy examination.

Differentiation Between Benign and Malignant Pigmented Skin Tumours Using Bedside Diagnostic Imaging Technologies: A Pilot Study.

Rapid diagnosis of suspicious pigmented skin lesions is imperative; however, current bedside skin imaging technologies are either limited in penetration depth or resolution. Combining imaging methods is therefore highly relevant for skin cancer diagnostics. This pilot study evaluated the ability of optical coherence tomography, reflectance confocal microscopy, photo-acoustic imaging and high-frequency ultrasound to differentiate malignant from benign pigmented skin lesions. A total of 41 pigmented skin tumours were scanned prior to excision. Morphological features and blood vessel characteristics were analysed with reflectance confocal microscopy, optical coherence tomography, high-frequency ultrasound and photoacoustic imaging images, and the diagnostic accuracy was assessed. Three novel photoacoustic imaging features, 7 reflectance confocal microscopy features, and 2 optical coherence tomography features were detected that had a high correlation with malignancy; diagnostic accuracy > 71%. No significant features were found in high-frequency ultrasound. In conclusion, optical coherence tomography, reflectance confocal microscopy and photoacoustic imaging in combination enable image-guided bedside evaluation of suspicious pigmented skin tumours. Combining these advanced techniques may enable more efficient diagnosis of skin cancer.

Clinical performance of a novel hyperspectral imaging device for cutaneous melanoma and pigmented skin lesions in Caucasian skin.

The quest for diagnostic tools for the detection of cutaneous malignant melanoma (cMM) is ongoing. A challenge in cMM care is not overlooking cMM at an early stage, while simultaneously avoiding unnecessary biopsies or excisions of benign pigmented skin lesions (PSLs). A novel hyperspectral imaging (HSI) device is shown to have potential for differentiating equivocal PSLs in Asian skin types. Our objective was to assess the accuracy of the HSI device in distinguishing between cMM and benign PSLs in patients with Caucasian skin types. Patients with Caucasian skin types (Fitzpatrick I-II), enrolled for excisional biopsies of PSLs were included and examined using the HSI device. The discrimination index (DI) was used to demonstrate the sensitivity (SE) and specificity (SP) in comparison with the re-evaluated histopathology diagnoses. In 186 patients, 202 pigmented skin lesions were included. The sensitivity to detect cMM was 96.7% (87/90), and the specificity for benign lesions was 42.1% (45/107). The AUC was 0.800 (95% confidence interval (CI): 0.740-0.861). Our novel HSI device showed a high sensitivity in detecting malignant lesions in patients with Caucasian skin types. Compared with analogous technologies, as multispectral imaging or electrical impedance spectroscopy, our device showed similar or better accuracy in differentiating cMM from benign PSLs. Therefore, it might be a useful clinical tool in skin types I-IV and where further triage of pigmented skin lesions is important.

Usefulness of high-frequency ultrasound in differentiating basal cell carcinoma from common benign pigmented skin tumors.

Basal cell carcinoma (BCC) is the most common cutaneous malignancy. Occasionally, it may have an appearance similar to that of some benign pigmented skin lesions. Therefore, additional information is needed to differentiate these lesions. A diagnostic accuracy study was performed from February 2018 to April 2019. All lesions underwent ultrasound examination with 50 and 20MHz probes. The high-frequency ultrasound (HFUS) images were evaluated independently by 2 experienced doctors for the presence of predefined features, including the depth, shape, margin, anechoic area, hyperechoic spots, epidermal interrupted echo, mushroom sign, flat-bottom sign, and superficial hyperechoic focus (SHEF). A total of 54 BCCs, 51 melanocytic nevi and 55 seborrheic keratoses (SK), were included. BCCs often involved the subcutaneous tissue (11/54, 20.4%; P<.001) and had an irregular shape (26/54, 48.1%; P<.001) and ill-defined borders (26/54, 48.1%; P<.001), while most benign pigmented lesions had a regular shape (101/106, 95.3%; P<.001) and well-defined borders (95/106, 89.6%; P<.001). BCCs occasionally showed anechoic areas (10/54, 18.5%; P<.001) and epidermal interrupted echo (18/54, 33.3%; P<.001). Moreover, hyperechoic spots could be found in BCCs (43/54, 79.6%), nevi (27/51, 52.9%), and SK (30, 54.5%) (P=.001), with mean number of 7.3, 5.5, and 8.0, respectively. The mushroom signs were all present in melanocytic nevi (18/51, 35.3%), while the flat-bottom sign (43/55, 78.2%; P<.001) and SHEF (40/55, 72.7%; P<.001) presented mainly in SKs. Based on the typical features, HFUS could improve the accuracy of BCC identification and should be considered when dermatologists are unsure about the lesion type.

Retrospective Analysis of Combined Treatment with Triple Combination Cream and Hyaluronic Acid Microneedle Patch for Benign Pigmented Skin Lesions

Benign pigmented skin lesions, particularly solar lentigines and seborrheic keratoses, commonly spur visits to a dermatologist...

Intense pulsed light for the treatment of pigmented and vascular disorders and lesions: A review

AbstractBackgroundIntense pulsed light (IPL) technology has evolved since its first introduction to the market in the 1990s. The underlying mechanism, similar to that of lasers, involves selective thermal damage to specific targets. IPL uses flashlamps and bandpass filters to emit pulsed light of adjustable wavelengths, fluences, and pulse durations. These features contribute to its versatility in treating a wide range of dermatological conditions.AimsThe purpose of this review is to highlight the history, mechanisms of action, and clinical applications of IPL in treating pigmented and vascular lesions, and to present a comparison of commonly‐used IPL devices available to the market.Materials and MethodsA literature search was conducted using electronic databases (Medline, Pubmed, Embase, CINAHL, EBSCO) and textbooks, in addition to the authors’ clinical experience on IPL therapy, and findings are presented here.ResultsStudies have demonstrated IPL to be an efficacious and safe modality for treating a variety of pigmented and vascular disorders and lesions, including postinflammatory hyperpigmentation, melasma, ephelides and solar lentigines, telangiectasias, port‐wine stains, poikiloderma of Civatte, rosacea, hemangiomas, venous malformations, and is comparable to other standard therapeutic options. Literature is supportive yet limited due to small sample sizes and short follow‐up periods.DiscussionThe adaptability and affordability of IPL often deem it a favorable primary or adjunctive option for treating benign pigmented and vascular skin lesions. IPL technology has evolved over time and modern devices are similar in both efficacy and side effect profile.

Lentigo Maligna: Clinical Presentation and Appropriate Management.

Lentigo maligna (LM) is a type of melanoma in situ that has distinctive characteristics regarding epidemiology, risk factors and clinical features. In addition, LM has a potential to progress to an invasive tumor with potentially aggressive behavior: lentigo maligna melanoma (LMM). Overall, LM has a very good prognosis, whereas LMM has the same prognosis as other invasive melanomas with similar Breslow thickness. LM/LMM represents a challenging entity not only regarding the diagnosis but also regarding the management. Diagnostic criteria are not well established, and there is an overlap of clinical, dermoscopic and pathological features with other benign pigmented skin lesions such as lentigines, pigmented actinic keratoses or macular seborrheic keratoses. LM/LMM’s common appearance within photodamaged skin makes lesion border identification difficult. Wide excisions are often required, but since LM/LMM typically appears on cosmetically sensitive areas such as the face, sometimes large excisions are not possible nor desirable. In this sense, specialized approaches have been developed such as margin-controlled surgery or image-guided treatment using reflectance confocal microscopy. Other treatments for LM such as cryosurgery, imiquimod, radiotherapy or photodynamic therapy have been proposed, although recurrence/persistence is common. The current manuscript reviews extensively the published data regarding the diagnosis, treatment and management of both complex entities LM and LMM.

Early Melanoma Detection in Primary Care: Clinical Recognition of Melanoma is Not Enough, One Must Also Learn the Basics.

To improve early melanoma detection, educational programs have been developed for general practitioners (GPs). This study aimed to determine whether the adjunct of teaching basic knowledge of pigmented skin lesions (PSL) to the training in melanoma diagnosis improves the GPs' diagnostic accuracy of melanoma. An interventional prospective study was conducted over a 3-month period where GPs attended a 2-h training course. The 1st session taught clinical melanoma recognition and the 2nd session instructed basic knowledge of PSL. Prior to training, after the 1st, and after the 2nd session, GPs were asked to select the malignant or benign nature of 15 clinical images associated to their clinical history. In total, 56 GPs participated in this study. The number of GPs identifying correctly ≥ 50% of the melanomas increased the most after the 1st session from 15 (26.8%; CI = (15.2; 38.4)) to 44 (78.6%; CI = (67.8; 89.3)) GPs (P < 0.001). The number of GPs correctly identifying ≥ 50% of the benign PSL only increased after completing the entire training, going from 10 (17.9%; CI = [(7.8; 27.9)) GPs to 50 (89.3%; CI = (81.2; 97.4)) GPs (P < 0.001). In this study, GPs identified benign PSL most accurately after the 2nd session. This suggested that teaching GPs the basics of PSL would especially improve their diagnostic accuracy for benign PSL, which could reduce unnecessary referrals to dermatologists. Teaching basic knowledge of PSL in addition to melanoma recognition seemed to enable GPs to triage skin lesions more effectively than when they were only trained to recognize melanoma.

Analysis of pigmented skin lesions and malignant melanoma by Laser Doppler flowmetry - Report of different cases and further analysis by a neuronal network.

Dermatoscopy is successfully used for the early diagnosis of suspicious skin lesions, however, correct diagnosis depends on training. There is evidence that wavelet analysis by Laser Doppler flowmetry (LDF) can identify malignant melanomas by their hypervascularization and changes in the capillary morphology. To show the capability of LDF in the distinction of melanomas and benign pigmented skin lesions based on data collected over 16 years. Evaluation of pigmented skin lesions was based on clinical information. The LDF measurements were taken. The suspect lesion was excised afterwards for histological work-up. Four case reports are presented. Data collected over 16 years was processed into a neuronal network to estimate the dignity of the lesion. A total of 517 suspicious lesions were analyzed by LDF. In the histological work-up, 114 lesions turned out to be melanomas, whereas 403 benign naevi were secured. Specificity to detect melanomas was good based on the clinical information. The LDF increases the sensitivity of melanoma detection, which is also illustrated in four case reports. In addition to clinical parameters, such as color and border, information from the LDF can help in the diagnosis of malignant melanomas. The LDF provides information on the vascularization of the skin lesion.

Non-Invasive Skin Cancer Diagnosis Using Hyperspectral Imaging for In-Situ Clinical Support.

Skin cancer is one of the most common forms of cancer worldwide and its early detection its key to achieve an effective treatment of the lesion. Commonly, skin cancer diagnosis is based on dermatologist expertise and pathological assessment of biopsies. Although there are diagnosis aid systems based on morphological processing algorithms using conventional imaging, currently, these systems have reached their limit and are not able to outperform dermatologists. In this sense, hyperspectral (HS) imaging (HSI) arises as a new non-invasive technology able to facilitate the detection and classification of pigmented skin lesions (PSLs), employing the spectral properties of the captured sample within and beyond the human eye capabilities. This paper presents a research carried out to develop a dermatological acquisition system based on HSI, employing 125 spectral bands captured between 450 and 950 nm. A database composed of 76 HS PSL images from 61 patients was obtained and labeled and classified into benign and malignant classes. A processing framework is proposed for the automatic identification and classification of the PSL based on a combination of unsupervised and supervised algorithms. Sensitivity and specificity results of 87.5% and 100%, respectively, were obtained in the discrimination of malignant and benign PSLs. This preliminary study demonstrates, as a proof-of-concept, the potential of HSI technology to assist dermatologists in the discrimination of benign and malignant PSLs during clinical routine practice using a real-time and non-invasive hand-held device.

Benign pigmented skin lesions

Benign pigmented skin lesions are extremely common. Such lesions are seen every day in general practice. The objectives of this paper are to develop a framework that may be used to evaluate pigmented skin lesions and a strategy for dealing with pigmented lesions, outline the conditions that improve the diagnosis of pigmented lesions (eg good lighting, careful inspection and dermoscopy), and increase clinician confidence in identifying pigmented lesions with concerning features. Regular assessment of pigmented skin lesions during patient consultations, including in an opportunistic fashion, will increase diagnostic acumen and help to identify potentially problematic lesions, and may improve patient awareness of lesions on their skin.

Improving clinical diagnosis of early-stage cutaneous melanoma based on Raman spectroscopy

BackgroundClinical diagnosis of early melanoma (Breslow thickness less than 0.8 mm) is crucial to disease-free survival. However, it is subjective and can be exceedingly difficult, leading to missed melanomas, or unnecessary excision of benign pigmented skin lesions. An objective technique is needed to improve the diagnosis of early melanoma.MethodsWe have developed a method to improve diagnosis of (thin) melanoma, based on Raman spectroscopy. In an ex vivo study in a tertiary referral (pigmented lesions) centre, high-wavenumber Raman spectra were collected from 174 freshly excised melanocytic lesions suspicious for melanoma. Measurements were performed on multiple locations within the lesions. A diagnostic model was developed and validated on an independent data set of 96 lesions.ResultsApproximately 60% of the melanomas included in this study were melanomas in situ. The invasive melanomas had an average Breslow thickness of 0.89 mm. The diagnostic model correctly classified all melanomas (including in situ) with a specificity of 43.8%, and showed a potential improvement of the number needed to treat from 6.0 to 2.7, at a sensitivity of 100%.ConclusionThis work signifies an important step towards accurate and objective clinical diagnosis of melanoma and in particular melanoma with Breslow thickness <0.8 mm.

Melasma: Quality of life before and after treatment

The self-esteem and body image alongside with the functional status are closely connected with patients` quality of life (QoL). The aim of the study is to assess the impact of melasma and other facial benign pigmented skin lesions on QoL. A secondary point was to evaluate the effect of the treatment on Heath related quality of life (HRQoL). Materials and Methods: The presented monocentric, prospective study includes 28 out-patients, with melisma and facial benign pigmentations. For the evaluation of QoL Dermatological Life Quality Index (DLQI) questionnaire was applied at the beginning and end of the treatment. Results: The DLQI score for facial pigmented disorders before treatment was 10.83 ± 1.62 (median 11.00; IQR 8.00-15.00) and after treatment 8.62±3.25 (median 9.00; IQR 6.00-12.00). There were no correlation between severity of pigmented disorders and the degree of their improvement and QoL. For patients with high expectation QoL before and after treatment show minor impairment. Therefore facial pigmented disorders affect the QoL of the patients mostly psychologically. Conclusion: The self-esteem and body image have negative influence on patients` wellbeing.

Reflectance Confocal Microscopy Criteria of Pigmented Squamous Cell Carcinoma In Situ.

Pigmented squamous cell carcinoma in situ (pSCCis) is difficult to diagnose based on clinical and dermoscopic examination. Reflectance confocal microscopy (RCM) allows noninvasive differentiation between malignant and benign pigmented skin lesions. We determined the frequency of key RCM features of pSCCis and correlated the RCM criteria with the corresponding dermoscopic and histopathologic criteria. The study included 28 lesions with biopsy-proven diagnosis of pSCCis derived from 28 patients. Clinical, dermoscopic, and RCM images of these lesions were retrospectively analyzed by 3 independent observers. Assessment for the presence of RCM criteria revealed scale or parakeratosis (20/28; 71%); irregular honeycomb pattern in the spinous-granular layer (28/28; 100%); spindle-shaped cells with dendritic branches infiltrating the epidermis (12/28; 43%); edged papillae (24/28; 86%), and dilated looped blood vessels within the papillae (18/28; 64%). Fifty-three percent of the cases displayed at least 4 RCM criteria and 96% of cases displayed at least 3 RCM criteria. We propose that the diagnosis of pSCCis could be established based on 1 major criterion-irregular honeycomb pattern-and 2 of the following minor criteria-scale or parakeratosis, spindle-shaped cells with dendritic branches infiltrating the epidermis, edged papillae, and dilated looped blood vessels within the papillae.

Optical detection and monitoring of pigmented skin lesions.

A method is presented for discriminating between malignant and benign pigmented skin lesions based on multispectral and multi-angle images. It is discussed how to retrieve maps of physiology properties and morphometric parameters from recorded images using a bio-optical model, radiative transfer calculations, and nonlinear inversion, and how to employ automated zooming to extract lesion and surrounding masks. Training and validation of a classification scheme for separation between benign and malignant tissue yielded sensitivity/specificity ranging from 97%/97% for application to a small dataset comprised of lesions not used for training and validation to 99%/93% for application to a larger dataset.

Analytical Characteristics of a Noninvasive Gene Expression Assay for Pigmented Skin Lesions

We previously reported clinical performance of a novel noninvasive and quantitative PCR (qPCR)-based molecular diagnostic assay (the pigmented lesion assay; PLA) that differentiates primary cutaneous melanoma from benign pigmented skin lesions through two target gene signatures, LINC00518 (LINC) and preferentially expressed antigen in melanoma (PRAME). This study focuses on analytical characterization of this PLA, including qPCR specificity and sensitivity, optimization of RNA input in qPCR to achieve a desired diagnostic sensitivity and specificity, and analytical performance (repeatability and reproducibility) of this two-gene PLA. All target qPCRs demonstrated a good specificity (100%) and sensitivity (with a limit of detection of 1-2 copies), which allows reliable detection of gene expression changes of LINC and PRAME between melanomas and nonmelanomas. Through normalizing RNA input in qPCR, we converted the traditional gene expression analyses to a binomial detection of gene transcripts (i.e., detected or not detected). By combining the binomial qPCR results of the two genes, an improved diagnostic sensitivity (raised from 52%- 65% to 71% at 1 pg of total RNA input, and to 91% at 3 pg of total RNA input) was achieved. This two-gene PLA demonstrates a high repeatability and reproducibility (coefficient of variation <3%) and all required analytical performance characteristics for the commercial processing of clinical samples.

Acquired Melanocytic Nevus: An Unusual Case Presentation

Acquired Melanocytic Nevi (AMV) are common benign pigmented skin lesions. There are three types which include junctional nevus, compound nevus and Intradermal Melanocytic Nevus (IMN). IMN are characterized clinically by dome-shaped, soft, fleshy papules and are seen commonly in adults. Herein we reported a case with an unusual large IMN. A 35 years old otherwise healthy male presented with history of asymptomatic skin lesion on his scalp of several years duration that started to get bigger within the previous few months prior presenting to us. Skin examination revealed solitary firm skin colored nodule measuring 1.5×1.5 cm on his scalp. Exccesional skin biopsy revealed sharply-defined intradermal tumor composed of nests and fascicles of nevus cells. The tumor cells in superficial dermis are composed of epithelioid cells arranged singly and in clusters with heavy pigmentation in the superficial part. The deeper portion of the tumor is composed of bland looking spindle cells. No atypia or mitosis has been seen. Nerve corpuscles resembling Meissner corpuscles have also been seen in the deeper portions of the tumor. Histochemical analysis showed positivity for S100 and HMB-45. On the basis of the above clinicopathological findings, the diagnosis of intradermal melanocytic nevus was made and the patient was reassured.