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Kissing nevi or split nevi are congenital melanocytic nevi on adjoining areas of the body formed as a result of separation during embryogenesis. Most kissing nevi are seen over the eyelids and only a handful of them have been reported over the penis. Becker’s melanosis is a common androgen dependent hamartoma with epidermal, melanocytic or smooth muscle origin. Herein, we describe the case of a 20-year-old male who presented with kissing nevi over the glans penis and prepuce. The patient also had a large Becker’s melanosis over the left side extending from the lower back to left lumbar area, the lateral aspect of left buttock and thigh till the knee. Our case is the first instance where a kissing melanocytic nevus is associated with Becker’s melanosis. [ABSTRACT FROM AUTHOR]

The value of dermoscopy in the detection of skin cancer is well established. Less is published on the utility of dermoscopy in the evaluation of pediatric skin disease. Our review (in two parts) aims to serve as an update on pediatric dermoscopy and to provide readers with a practical application for the use of dermoscopy in pediatric dermatology clinics. In part I, we propose a dermoscopy algorithm for pediatric skin disease and melanocytic growths, and in part II, we address vascular growths, common skin infections, and inflammatory conditions for which dermoscopy is valuable. [ABSTRACT FROM AUTHOR]

Objective: To investigate the application and challenge of reflectance confocal microscopy (RCM) in the diagnosis of pigmented nevus. Method: A total of 997 patients with clinical diagnosis of pigmented nevus were included in the study, and RCM imaging was performed on the lesion of each patient. A biopsy was performed in 78 of these patients for histological diagnosis. We retrospectively analyzed the results of RCM diagnosis and histological diagnosis and then found the RCM characteristics of the histologically confirmed lesion. Results: According to the RCM images, 823 of the 997 (82.55%) patients were diagnosed with pigmented nevus, while 113 (11.33%) were not diagnosed by dermatologists using RCM. Of the 78 biopsy lesions, 36 of the 46 (78.26%) cases diagnosed with pigmented nevus were consistent with histological diagnosis, while three were rediagnosed with dermatofibromas, four were seborrheic keratosis, one was malignant melanoma in situ, and two were lentigo. Conclusion: RCM exhibits a high diagnostic accuracy for patients with clinical diagnosis of pigmented nevus. However, due to the limitation of RCM scanning depth and the commonality of the microscopic characteristics of related diseases, RCM still faces certain challenges in the diagnosis of pigmented nevus. [ABSTRACT FROM AUTHOR]

Background: Skin cancer is one of the most common forms of cancer in the world and melanoma is the deadliest type of skin cancer. Both melanoma and melanocytic nevi begin in melanocytes (cells that produce melanin). However, melanocytic nevi are benign whereas melanoma is malignant. This work proposes a deep learning model for classification of these two lesions. Methods: In this analytic study, the database of HAM10000 (human against machine with 10000 training images) dermoscopy images, 1000 melanocytic nevi and 1000 melanoma images were employed, where in each category 900 images were selected randomly and were designated as the training set. The remaining 100 images in each category were considered as the test set. A deep learning convolutional neural network (CNN) was deployed with AlexNet (Krizhevsky et al., 2012) as a pretrained model. The network was trained with 1800 dermoscope images and subsequently was validated with 200 test images. The proposed method removes the need for cumbersome tasks of lesion segmentation and feature extraction. Instead, the CNN can automatically learn and extract useful features from the raw images. Therefore, no image preprocessing is required. Study was conducted at Shahid Beheshti University of Medical Sciences, Tehran, Iran from January to February, 2020. Results: The proposed model achieved an area under the receiver operating characteristic (ROC) curve of 0.98. Using a confidence score threshold of 0.5, a classification accuracy of 93%, sensitivity of 94%, and specificity of 92% was attained. The user can adjust the threshold to change the model performance according to preference. For example, if sensitivity is the main concern; i.e. false negative is to be avoided, then the threshold must be reduced to improve sensitivity at the cost of specificity. The ROC curve shows that to achieve sensitivity of 100%, specificity is decreased to 83%. Conclusion: The results show the strength of convolutional neural networks in melanoma detection in dermoscopy images. The proposed method can be deployed to help dermatologists in identifying melanoma. It can also be implemented for self diagnosis of photographs taken from skin lesions. This may facilitate early detection of melanoma, and hence substantially reduce the mortality chance of this dangerous malignancy. [ABSTRACT FROM AUTHOR]

Background: Long‐pulsed (LP) lasers at pulse durations of 1‐300 ms have been used to destroy nests of nevi cells by selectively targeting pigment chromophores. Objective: To evaluate dual‐wavelength LP laser‐induced tissue reactions. Methods: The patterns of LP 755‐nm alexandrite (Alex) and/or 1064‐nm neodymium (Nd):yttrium‐aluminum‐garnet (YAG) laser‐induced tissue reactions were macroscopically evaluated using a tattoo‐embedded phantom. Additionally, a pilot in vivo human study was performed for common acquired melanocytic nevus, of which dermoscopic images and high‐speed cinematographs were obtained. Results: Combinations of Nd:YAG and Alex laser treatments at interpulse intervals of 10 or 20 ms generated round to oval zones of photothermal and photoacoustic injury in two distinctive areas containing disintegrated tattoo particles. Treatment at interpulse intervals of 10 or 20 ms between Alex and Nd:YAG pulses elicited lesser degrees of thermal damage to surrounding tissues, compared to treatment at 100 or 200 ms. Immediately after combined LP laser treatment of human nevus lesions in vivo, Nd:YAG‐Alex treatment at a 20‐ms interpulse interval exhibited more remarkable crusting and erosive appearances than Alex‐Nd:YAG treatment. Conclusion: For treating pigmented disorders, sequential delivery of LP Nd:YAG and Alex pulses at short interpulse intervals of 10‐20 ms can effectively destroy nests of pigment chromophores. [ABSTRACT FROM AUTHOR]

Phacomatosis pigmentokeratotica (PPK) is characterized by the co-existence of epidermal nevi and large segmental speckled lentiginous nevi of the papulosa type. PPK, previously explained as 'twin spot' mosaicism due to the postzygotic crossing-over of two homozygous recessive mutations, has recently been shown to derive from one postzygotic activating RAS mutation. Epidermal nevi, including those in PPK, are known to give rise to neoplasms such as trichoblastoma and basal cell carcinoma. Within speckled lentiginous nevi, Spitz nevi and melanoma have been well documented. We report a case of PPK with a combined melanocytic and adnexal neoplasm presenting where the nevi conjoined. Using next-generation sequencing techniques, we were able to identify the same HRAS G13R mutation within both components of the tumor, and to show the absence of additional mutated modifier genes in a panel of 300 cancer-related genes. Given the genetic findings in this rare tumor-type, we suggest that this case may be used as a model for understanding the development of biphenotypic neoplasia or intratumoral heterogeneity in some cases. [ABSTRACT FROM AUTHOR]

Objective　Through clinical observation and statistics，to get the best curative effect of surgical operation in treating pigment nevus method and provide clinical guidance. Methods　We reviewed of face and neck patients (1100 patients) with pigmented nevus in the department in the department of the dermatology，plastic surgery from January 2013 to October 2015，two different methods was designed on each parts and effect of the treatment, especially satisfaction degree was analyzed by statistical methods．Results　In 100 cases of patients, only 20 patients had mild scar hyperplasia at the neck incision and the rest of the patients were satisfactory. For special parts such as mouth，nose and eye around，along the direction of the muscle, arc and along the direction of dermatoglyph incision was designed respectively, patients obtained with higher postoperative satisfaction （P < 0.05）. Conclusion　In pigmented nevus of face and neck surgery treatment, surgical incision design requires dynamic and static combining method，incision design is important for the postoperative effect and patients' satisfaction. [ABSTRACT FROM AUTHOR]

This learning exercise challenges clinicians and dermatopathologists to consider the differential diagnosis of an unevenly colored solitary papule over the upper back of an adolescent female. [ABSTRACT FROM AUTHOR]

Electrical bio-impedance can be used to assess skin cancers and other cutaneous lesions. The aim of this study was to distinguish skin cancer from benign nevi using multifrequency impedance spectra. Electrical impedance spectra of about 100 skin cancers and 511 benign nevi were measured. Impedance of reference skin was measured ipsi-laterally to the lesions. The impedance relation between lesion and reference skin was used to distinguish the cancers from the nevi. It was found that it is possible to separate malignant melanoma from benign nevi with 75% specificity at 100% sensitivity, and to distinguish nonmelanoma skin cancer from benign nevi with 87% specificity at 100% sensitivity. The power of skin cancer detection using electrical impedance is as good as, or better than, conventional visual screening made by general practitioners. [ABSTRACT FROM AUTHOR]

Background. Nevus density in children, a well-known risk factor for malignant melanoma, depends both on constitutional factors and on previous ultraviolet (UV) exposure. Secular trends of childhood UV exposure could thus be indirectly monitored by repeated standardized surveys assessing nevus density in children, such as the “childhood monitoring of nevus density (CMONDE-Study)”.Methods. Two complete surveys comprising all children at the time of school enrolment were performed in the city and county of Go¨ttingen, Germany, during the years 1999 and 2000. A total of 4252 children with a median age of 6.25 years were examined as part of the mandatory school enrolment health assessment, and complete data were available for 3881 children.Results. Median nevus density was 5.8/m2 in the entire study group. The subgroup-specific median increased from “Fitzpatrick skin type” IV to II, but the density was not increased for the type I subgroup. Similarly, nevus density rose with increasing lightness of hair color, but was very low in red-haired individuals. While the number of freckles was also strongly associated with nevus density, the association between iris color and skin reflectance, respectively, was weak. The duration of the additional examination for CMONDE was on average 3–5 min per child.Conclusion. We regard CMONDE as a highly feasible surveillance instrument, which should be implemented as an important addition to regular regional or national health reporting. [Copyright &y& Elsevier]

Congenital melanocytic nevus consists of congregations of nevomelanocytes. It is found in approximately 1% of new born infants. Congenital melanocytic nevus needs to be excised before it transforms into a malignant lesion. Many strategies have been attempted for the removal and reconstruction of the nevus. Serial excision enables wound closure to be accomplished with a shorter scar than if the original lesion was elliptically excised in a single stage and reorientation of the scar closer to the relaxed skin lines. The routine utilization of an elliptical serial excision as a standard method of closure often leads to the formation of elongated scars and waste of skin. The "Cogwheel pattern" serial excision is a new technique for reducing the size of the nevus efficiently. Reducing the final scar length, distributing the tension over many directions, and having the chance of decrease in operation numbers are ultimately achieved with the use of the "Cogwheel pattern" serial excision. [ABSTRACT FROM AUTHOR]