Introduction: One of the most challenging dermoscopic situations is to distinguish between early melanomas and doubtful benign nevi. At times, suspicious melanocytic lesions have dermoscopic features similar to melanomas, thus leading to excessive excisions of lesions.
Objective: To develop a dermoscopic model that helps to differentiate the doubtful nevus from the early melanoma.
Material and methods: A total of 219 histopathologically confirmed dermoscopic images were analyzed and a comparison between doubtful nevi and early melanomas was then performed.
Results: The final model was based on three dermoscopic features: radial streaming, blue hue and vascular structures. If all three features were absent, it was most likely a nevus; if one dermoscopic feature was present, it could be a nevus or melanoma; if two features were present, there was a greater probability of melanoma diagnosis; if three features were present, it was melanoma.

Keywords: DERMOSCOPY, MELANOMA, NEVUS, PIGMENTED

Giant congenital melanocytic nevi are extremely rare, however there is a 5-10% chance they will develop into melanomas. Laser-based treatment of this type of lesion is still very controversial. Some studies report great success without malignant development and others have achieved good aesthetic results but with malignancy. This article describes the clinical and histological development of a case of a female patient with a giant congenital melanocytic bathing trunk nevus, after 14 sessions of 1,064 nm Q-Switched Nd:YAG laser and three years of follow-up without histological signs of malignancy. The authors highlight the need for histological monitoring of this type of lesions.

Keywords: NEVUS, NEVUS, PIGMENTED, LASER THERAPY

The prognosis of cutaneous melanomas depends mainly on the lesions' thickness; early detection is of paramount importance for patient longer survival rates. An accuracy of approximately 90% can be achieved using dermoscopic assessment. Since early melanomas might not present specific dermoscopic features, they can only be diagnosed by observing alterations over time through total body mapping and serial digital dermoscopy. Patients with atypical nevus syndrome and multiple familial melanoma presented a higher sensitivity for the detection of melanoma using that technique.

Keywords: MELANOMA; DERMOSCOPY; DYSPLASTIC NEVUS SYNDROME.

Introduction: Nevus of Ota is a dermal melanocytic nevus located in the skin area that is innervated by the second and third branches of the facial nerve. It occurs mainly in patients of Asian ethnic background. The present study was aimed at evaluating the therapeutic response in the Western population, where higher skin types and characteristics diverse from those that have already been studied are common. Methods: A retrospective study based on the analysis of medical records, an active search of patients and the application of a questionnaire. All study patients were treated with 1,064 nm Q-Switched Nd:YAG laser, with or without a 532 nm tip, with 1 to 4-month intervals between sessions, 10ns pulse duration, 3mm spot size, 1 to 3 Hz frequencies and 2 to 12 J/cm2fluences. Results: According to the research physicians' evaluation, from the seven assessed patients, three had excellent improvement (greater than 75%), two had good response (51-75%) and one had moderate response (25-50%). The analysis of the degree of patient satisfaction showed that four patients reported being very satisfied and three, satisfied. The best results were observed in patients with phototypes up to grade IV and after having undergone seven sessions. Conclusions: QS lasers have proven a useful tool for treating patients with Nevus of Ota and high skin phototypes.

Keywords: NEVUS OF OTA, TREATMENT OUTCOME, LASERS

Introduction: In vivo confocal microscopy is an auxiliary non-invasive diagnostic method used in the diagnosis of hyperpigmented lesions in scars. Objectives: To evaluate hyperpigmentation in the scars of benign and malignant melanocytic lesions through confocal microscopy examination. Methods: Clinical, dermoscopic, and confocal microscopy images of fourteen patients with hyperpigmentation in adequately treated melanoma scars and in excised melanocytic nevi, were evaluated. Results: Among the eight patients with hyperpigmentation in melanoma scars, four showed no suspicious structures after confocal microscopy examination and four showed suspicious structures. Among the six patients with hyperpigmentation in areas where melanocytic nevi had been excised, three had atypical structures, such as dendritic cells and non demarcated papillae. Patients with suspicious structures underwent histological examination, with one case of hyperpigmentation in a lentigo maligna scar evidencing recurrence. Conclusions: The examination method allowed for the avoiding of biopsy in confirming the diagnosis in six of the fourteen patients. The finding of cells with dendritic or pagetoid pattern in the confocal microscopy examination means a diagnostic challenge, for it can indicate melanocytes or Langerhans cells in the spinous layer. Therefore, lesions that have such structures must be removed for histology and differential diagnosis.

Keywords: MELANOMA, NEVUS, DERMOSCOPY, CONFOCAL MICROSCOPY.

The authors describe the case of a 54-year-old woman presenting papules and yellowish plaques on the right thigh for 15 years, which clinically resembled a plane xanthoma. An anatomical pathological examination evidenced a mature adipose tissue in the dermis, with a diagnosis of superficial cutaneous lipomatous nevus, a rare benign hamartomatous malformation characterized by the presence of ectopic mature adipocytes in the dermis.

Keywords: NEVUS; ADIPOCYTES; XANTHOMATOSIS

Knowledge, diagnostic ability and surgical skills for approaching diverse cutaneous conditions in the auricular region are parts of a dermatologist physician’s daily routine. In the second part of this review article, will be approached the benign neoplasms of the auricular region, describing their particularities and ideal methods of treatment.

Keywords: Ear; Nevus; Cysts; Keloid

Malignant melanoma is a melanocyte tumor responsible for more than 75% of skin cancer deaths. The rare variants of this pathology are responsible for 5% of the cases and may mimic other pathologies. We report the case of a patient with spitzoid melanoma and we discuss the dermoscopic, histopathological, and immunohistochemical findings, as well as the follow-up of this rare variant of melanoma.

Keywords: Melanoma; Nevus, epithelioid and spindle cell; Melanoma-specific antigens; Skin neoplasms; Dermoscopy

Nevus lipomatosus cutaneous superficialis is an uncommon dermatosis in which the adipose tissue is present ectopically in the dermis.This condition is clinically divided into two variants: classical and solitary.The first is characterized by soft, pedunculated, cerebriform, skin-colored or yellowish papules or nodules, mainly involving the pelvic region.The latter is observed as a solitary or sessile papule. Treatment with surgical excision is usually enough. Nevus lipomatosus cutaneous superficialis may be associated with other conditions such as multiple lipomas, as in our case.

Keywords: Nevus; Dermis;Adipocytes; Lipoma

The nevus spilus (NS), also known as speckled lentiginous nevus or nevus on nevus, is represented by a brownish macule on which small macules of darker shades appear. It is more common on the trunk and lower limbs. The general population's prevalence is 0.2% to 2.3%, and they have a benign character. The exact risk for malignant transformation is still unknown; thus, it demands a routine clinical-dermoscopic follow-up. We present a case of malignant melanoma on acquired nevus spilus, in which early an excision was performed, with no recurrence, highlighting the importance of follow-up of these patients.

Keywords: Melanoma; Nevi and melanomas; Nevus

INTRODUCTION: With the advancement of digital image analysis, predictive analysis, and machine learning methods, studies have emerged regarding the use of artificial intelligence in imaging tests such as dermoscopy.
OBJECTIVE: Construction, testing, and implementation of an artificial neural network based on characteristics of dermoscopic images.
METHODS: 1949 images of melanocytic nevi and melanomas were included, both from the authors’ files and from dermoscopic image banks available on the internet, and routines and plugins were developed to extract 58 features applied to a multilayered neural network construction algorithm. Also, 52 dermatologists assessed 40 random images and compared the results compared.
RESULTS: The training and testing of the neural network obtained a correct percentage of classification of 78.5% and 79.1%, respectively, with a ROC curve covering 86.5% of the area. The sensitivity and specificity of dermatologists were 71.8% and 52%. For the same images and a cutoff point of 0.4 (40%) of the output value, the application obtained 62% and 56% values, respectively.
CONCLUSIONS: Multilayer neural network models can assist in the dermoscopic evaluation of melanocytic nevi and melanomas regarding the differential diagnosis between them.

Keywords: Artificial intelligence; Diagnosis; Melanoma; Nevus

The divided nevi occur in contiguous areas of the skin that are mostly benign lesions. We report six cases of nevus divided on the penis and its dermoscopic patterns. Clinical follow-up was the best therapeutic option for this group of patients, considering the location of these lesions.

Keywords: Dermoscopy; Nevus; Intradermal nevus; Pigmented nevus; Penis

Melanoma is a rare neoplasm in the pediatric population, and it is even rarer in children under 10 years of age. Total body mapping constitutes a low-cost and non-invasive method that increases diagnostic accuracy in evaluating pigmented lesions, especially in high-risk patients. We reported the case of a 9-year boy with dysplastic nevus syndrome, in which one lesion presented a subtle change (asymmetry of structures) within a 6-months follow-up. Its excision resulted in melanoma with a Breslow thickness of 1 mm and a negative sentinel lymph node. Total body mapping reduces the number of unnecessary excisions. It allows diagnosis of melanomas in early and potentially curable stages, especially in children and patients with risk factors such as dysplastic nevus syndrome. We report this case due to the rarity of the neoplasia in this age group and also to demonstrate the importance of sequential digital dermoscopy in early diagnosis of melanoma in this population.

Keywords: Dermoscopy; Melanoma; Dysplastic nevus syndrome

Blue nevus is a benign lesion arising from dermal melanocytes containing large amounts of melanin. The agminated variant presents a cluster of blue nevus lesions with linear or blaschkoid distribution. We report two cases of patients with agminated blue nevus that developed on previous acne scars, and dermoscopy helped a lot in the differential diagnosis. This is the first occurrence found in the literature of agminated blue nevus that appeared on a previous scar, which may have occurred by chance or as a result of the collagen remodeling process inherent to the healing process.

Keywords: Scar; Collagen; Dermoscopy; Nevus blue

Dermoscopy is a practical, non-invasive tool that can be used to distinguish tinea nigra from other lesions that appear macroscopically similar, including acral nevus. Under dermoscopy, tinea nigra presents with a pattern of spiculated gray-brown pigment deposition, whereas acral nevus most often presents as brown pigment deposition in a parallel furrow pattern.

Keywords: Dermoscopy; Nevus; Tinea