Dermoscopy in Merkel Cell Carcinoma: a Case Report

Merkel cell carcinoma (MCC) is a rare malignant and primary neuroendocrine carcinoma with several known risk factors. Early diagnosis and aggressive treatment are critical. We report the case of an 82-year old woman with a Merkel cell carcinoma on the face. Clinical and histopathological features are presented. In addition, dermoscopic features and the differential diagnosis of this rare tumor are discussed. Although nodules with atypical dermoscopic vascular pattern and milky-red areas will end up being excised, this report adds more clues to the rarely described dermoscopic morphologic presentation of MCC.

Morfologia e Padrões Vasculares em Dermatoscopia - Parte I. Princípios Básicos

A dermatoscopia constitui uma técnica de diagnóstico não-invasiva, in vivo, que permite complementar a observação clínica de lesões cutâneas não-pigmentadas de etiologia diversa. Nos tumores cutâneos não-pigmentados, a dermatoscopia facilita a observação de estruturas vasculares, aumentando a acuidade no seu diagnóstico, distinguindo tumores melanocíticos e não-melanocíticos, benignos e malignos. Na parte I deste artigo são discutidos os princípios básicos da avaliação dermatoscópica dos tumores cutâneos não-pigmentados, incluindo a morfologia vascular e os padrões de distribuição dos vasos, assim como de outras pistas adicionais.

Morfologia e Padrões Vasculares em Dermatoscopia - Parte II. Prática Clínica

A dermatoscopia constitui uma técnica de diagnóstico não-invasiva, in vivo, que permite complementar a observação clínica de lesões cutâneas não-pigmentadas de etiologia diversa. Nos tumores cutâneos não-pigmentados, a dermatoscopia facilita a observação de estruturas vasculares, aumentando a acuidade no seu diagnóstico, distinguindo tumores melanocíticos e não-melanocíticos, benignos e malignos. Na parte II descreve-se a variabilidade da aplicação clínica da dermatoscopia em lesões cutâneas não-pigmentadas tumorais.

Melanoma and Satellite Blue Papule

The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slow-growing malignant melanoma was made. Simultaneously, a well-defined blue papule was seen on the proximal third of the same arm. Dermoscopy disclosed a homogeneous blue pattern. After clinical and dermoscopic correlation our differential diagnosis for this blue lesion included cutaneous melanoma metastasis, blue nevus and foreign body reaction. The patient recalled its onset 75 years ago after a grenade explosion. We also discuss the blue lesion appearance under reflectance confocal microscopy and high-definition optical coherence tomography. Histopathological examination after excision of the hyperpigmented patch and blue papule revealed a melanoma in situ and a foreign body reaction, respectively. The diagnostic evaluation of a blue lesion should always rely on the integration of all data, especially clinical and dermoscopic features. Other non-invasive techniques, like reflectance confocal microscopy and high-definition optical coherence tomography can also be important aids for its differential diagnosis.

Porokeratosis Ptychotropica of the Scrotum: Dermoscopic Evaluation of an Atypical Presentation

Porokeratosis ptychotropica is a rare variant of porokeratosis that is classically located on the gluteal and perianal regions, seldom extending to the genitalia. The authors report an atypical presentation of porokeratosis ptychotropica and discuss the use of dermoscopy in evaluating this dermatosis. Dermoscopic findings, although not specific to this variant of porokeratosis, are helpful in the differential diagnosis of other genital disorders. Histopathology, through the visualization of multiple cornoid lamellae, prevails as the gold standard for the definite diagnosis of porokeratosis ptychotropica.