Characteristic Dermoscopic Features Research Articles

Learning Reflectance Confocal Microscopy of Melanocytic Skin Lesions through Histopathologic Transversal Sections

Histopathologic interpretation of dermoscopic and reflectance confocal microscopy (RCM) features of cutaneous melanoma was timidly carried out using perpendicular histologic sections, which does not mimic the same plane of the image achieved at both techniques (horizontal plane). The aim of this study was to describe the transverse histologic sections research technique and correlate main dermoscopic features characteristic of cutaneous melanoma (atypical network, irregular globules and pseudopods) with RCM and histopathology in perpendicular and transverse sections in order to offer a more precise interpretation of in vivo detectable features. Four melanomas and 2 nevi with different dermoscopic clues have been studied. Lesion areas that showed characteristic dermoscopic features were imaged by dermoscopy and confocal microscopy and directly correlated with histopathology in perpendicular and transverse sections. We presented the possibility to perform transverse sections as a new approach to understand RCM features. Atypical network showed different aspects in the 2 melanomas: in one case it was characterized by pleomorphic malignant melanocytes with tendency to form aggregates, whereas in the other elongated dendritic cells crowded around dermal papillae, some of them forming bridges that resembled the mitochondrial aspect at confocal and histopathology transversal sections. Pigment globules in melanomas and nevi differed for the presence of large atypical cells in the former, and pseudopods showed up as elongated nests protruded toward the periphery of the lesion. Transverse histologic research sections have a consistent dermoscopic and confocal correlate, and it may represent an help in confocal feature interpretation and an advance in improving melanoma diagnosis and knowledge of the biology of melanocytic lesions.

Characteristic dermoscopic features of primary cutaneous amyloidosis: a study of 35 cases

Primary cutaneous amyloidosis (PCA) is a relatively common skin disorder among Asians and South Americans. It is usually diagnosed clinically. However, for cases with atypical presentations, the diagnosis can be a challenge and skin biopsy may be necessary. Dermoscopy has been proved to be a valuable, noninvasive tool in the diagnosis of cutaneous pigmented diseases. Most lesions of PCA show hyperpigmentation and the major histopathological abnormalities of PCA occur in the epidermis and dermal papillae. Dermoscopy might be a powerful tool to provide valuable information for the diagnosis of PCA. We aimed to find characteristic dermoscopic features of PCA. Cases with typical clinical presentations of PCA, either macular or lichen subtypes, were included in this study. All were evaluated using a hand-held, polarized and nonpolarized dermoscope. A total of 35 patients with clinically diagnosed PCA were enrolled. Eighteen patients had lesions consistent with macular amyloidosis and 17 with lichen amyloidosus. We found two major dermoscopic patterns characteristic of PCA. The most common dermoscopic finding of PCA was a central hub, which could be either white or brown, surrounded by various configurations of pigmentation. For cases of lichen amyloidosus with prominent hyperkeratosis, the central hub was replaced by a scar-like morphology. This is the first study to report the characteristic dermoscopic features of PCA. We demonstrate that the use of a dermoscope may assist in achieving an accurate diagnosis of PCA.

Dermoscopic Characteristics of Congenital Melanocytic Nevi Affecting Acral Volar Skin

To characterize the dermoscopic features of acral congenital melanocytic nevi (CMN). Retrospective independent evaluation of dermoscopic images by 2 dermoscopists. A dermatology clinic at a university hospital. Using the files of the clinic from January 1, 2004, through February 28, 2009, we selected cases with CMN lesions affecting acral volar skin that were present at birth or developed within the first few months of life. Characteristic dermoscopic features and their frequencies. We collected a total of 24 acral CMN lesions. Dermoscopically, 9 lesions (38%) showed a combination of the crista dotted pattern and the parallel furrow pattern. Of these 9 lesions, 1 also had a fibrillar pattern. The remaining 15 lesions showed the following single-component patterns: the parallel furrow pattern in 6 (25%), the crista dotted pattern in 3 (12%), the fibrillar pattern in 2 (8%), and the globular, globulostreaklike, nontypical, and parallel ridge patterns in 1 each (4%). We also followed up 6 lesions for several years. Changes in the dermoscopic features were observed in 4 CMN lesions from patients younger than 14 years. Three lesions had a combination of the crista dotted and parallel furrow patterns on the first visit that changed to the nontypical pattern; in addition, the degrees of pigmentation decreased during follow-up. In the remaining lesion, the globulostreaklike pattern changed to the parallel furrow pattern. Most CMN lesions affecting acral volar skin show characteristic dermoscopic features distinguishable from acral melanoma. The combination of the crista dotted and parallel furrow patterns (ie, peas-in-a-pod pattern) is the most common feature in acral CMN. Some lesions of acral CMN fade during childhood.

Dermoscopy can be useful in differentiating scalp psoriasis from seborrhoeic dermatitis

Psoriasis and seborrhoeic dermatitis are common erythematous-squamous dermatoses that may present with scaly erythematous patches on the scalp. Owing to the similar clinicopathological features of these dermatoses, their differentiation poses a diagnostic challenge, particularly when the lesions on the scalp are isolated. To evaluate the usefulness of dermoscopy in the clinical differentiation of scalp psoriasis and seborrhoeic dermatitis. This was a retrospective observational study to evaluate the characteristic dermoscopic features of scalp psoriasis and seborrhoeic dermatitis. The study included a total of 96 patients with lesions; these patients were recruited from two tertiary teaching hospitals in Korea (Pusan National University Hospital and Kyungpook National University Hospital). Among these, 55 patients had scalp psoriasis and 41 patients had seborrhoeic dermatitis. The most significant dermoscopic features of scalp psoriasis were red dots and globules, twisted red loops, and glomerular vessels. In contrast, seborrhoeic dermatitis was characterized by arborizing vessels and atypical red vessels with the absence of red dots and globules. Featureless areas devoid of any particular vascular patterns were also frequently observed in seborrhoeic dermatitis. Dermoscopic findings of red lines and other vascular patterns were not considered useful for differentiation because these were uncommon features in both diseases. Although scales were observed commonly in both diseases, there was no significant difference in the frequency and characteristics of the scales when they were observed using dermoscopy. Our study shows that the investigation of vascular patterns by using dermoscopy can be valuable for the clinical diagnosis and differentiation of scalp psoriasis and seborrhoeic dermatitis.

Dermoscopic Features of a Black Hairy Tongue in 2 Japanese Patients

Dermoscopic features of a black hairy tongue have never been reported. Dermoscopy might be useful in speculating pathologic features of oral lesions. The objective was to identify additional dermoscopic criteria. Two Japanese patients who were clinically given a diagnosis of “black hairy tongue” were evaluated for dermoscopic features. We have shown characteristic dermoscopic features of brownish hair-like elongation of filiform papillae with whitish lingual papillae. Dermoscopic examination seemed useful as an adjunct to the diagnosis of this benign disorder of the tongue, demonstrating exact changes in shape and color of filiform papillae. It might also be helpful in more objective observation of the therapeutic efficacy.

Dermoscopy Patterns of Halo Nevi

Halo nevi (HN) are benign melanocytic nevi surrounded by a depigmented area (halo). This study aims to evaluate the dermoscopic features of HN and their changes during digital dermoscopic follow-up and to investigate the frequency of the halo phenomenon in a series of melanomas. In a retrospective study, digital dermoscopic images of HN from patients who attended the Pigmented Skin Lesions Clinic of the Department of Dermatology, Medical University of Graz, between October 1, 1997, and March 31, 2004, were reviewed and classified by dermoscopic morphologic criteria. For HN that were followed up with digital dermoscopy, the percentages of changes in the size of the nevus and halo components were calculated. In addition, digital dermoscopic images of histopathologically confirmed melanomas obtained from the same database were reviewed for the presence of an encircling halolike depigmentation. We classified 138 HN in 87 patients (mean age, 22.4 years). The most common dermoscopic structures were the globular and/or homogeneous patterns in more than 80% of HN. Follow-up of 33 HN revealed considerable size reduction of the nevus component, but this was not associated with significant structural changes. Of a total of 475 melanomas, only 2 revealed an encircling halo, but both displayed clear-cut melanoma-specific patterns according to dermoscopy. Halo nevi exhibit the characteristic dermoscopic features of benign melanocytic nevi, represented by globular and/or homogeneous patterns that are typically observed in children and young adults. Halo nevi reveal considerable changes of area over time during digital dermoscopic follow-up, albeit their structural patterns remain unchanged. For this reason and because melanoma with halolike depigmentation, despite being rare, additionally exhibits melanoma-specific dermoscopic criteria, the role of digital dermoscopic follow-up in the diagnosis of HN is insignificant.

Dermoscopic Features of Mucinous Carcinoma of the Skin

BACKGROUND Dermoscopic features of nonpigmented skin lesions are seldom reported; dermoscopy might be useful in speculating pathologic features in the upper dermis. OBJECTIVE The objective was to identify additional dermoscopic criteria. METHODS Dermoscopy of the mucinous carcinoma of the skin occurring on the cheek of a 69-year-old man was performed. RESULTS We have shown characteristic dermoscopic features of whitish network and light-brown globules and they correspond to the pathologic findings of fibrous septum and mucinous deposition, respectively. DISCUSSION Dermoscopic examination seemed useful as an adjunct to the diagnosis of this rare nonpigmented malignant neoplasm.

Dermoscopy for acral pigmented skin lesions

Acral volar skin is the most prevalent site of malignant melanoma in nonwhite populations. In Japanese, about one half of all cutaneous melanomas are seen on acral skin, and nearly 30% of melanomas affect the sole of the foot.1,2 The rate of acral melanoma is much higher in blacks. Moreover, the incidence and real number of malignant melanoma affecting the acral skin were reported to be almost the same among all races, the incidence being 0.3/100,000 populations per year.3,4 In any race, therefore, early detection and accurate diagnosis of malignant melanoma on acral skin are very important to improve the prognosis. On acral skin, melanocytic nevi are also frequently found. In our data, 8% of Japanese have melanocytic nevi on their soles.1 In addition, we sometimes encounter nonmelanocytic pigmented lesions on acral skin, such as the so-called black heel, which may produce problems in clinical differentiation from early melanoma. In this article, we describe characteristic dermoscopic features of various kinds of pigmented lesions on acral skin and emphasize the diagnostic value of the parallelridge pattern in diagnosing early melanoma at this anatomic site. Using this dermoscopic criterion, we detected several cases of early melanoma in situ, which were difficult to be diagnosed clinically and/or histopathologically.

メラノーマの早期病変診断におけるｄｅｒｍｏｓｃｏｐｙの有用性

We investigated the characteristic dermoscopic features of early lesions of malignant melanoma. On dermoscopy, malignant melanoma in situ and the macular portions of invasive malignant melanoma affecting glabrous skin showed accentuated pigmentation on the ridges of the skin markings, which are arranged in parallel. This “parallel ridge pattern” was exclusively found in malignant melanoma in situ and the macular portion of invasive malignant melanoma. In contrast, benign melanocytic nevi on glabrous skin showed, in most cases, one of the following 3 typical dermoscopic patterns: (1) parallel furrow pattern, (2) lattice-like pattern, and (3) fibrillar or filamentous pattern.On non-glabrous skin, malignant melanoma in situ and the macular portion of invasive malignant melanoma showed highly irregular pigment network, pseudopods, radial streaming and irregular black dots or brown globules. Other pigmented lesions such as basal cell carcinoma, seborrheic keratosis, solar lentigo and black heel also showed distinctive dermoscopic features, respectively. Because of these characteristic features, we can effectively detect early melanoma using this noninvasive method. [Skin Cancer (Japan) 2001; 16: 13-21]