The Usefulness of Dermoscopy for the Recognition of Malignant Collision Tumors.

BACKGROUND: Preoperative diagnosis of malignant collision tumors (MCT) is extremely difficult. The value of dermoscopy to improve the correct detection of these tumors has not been previously studied. This study aims to evaluate the diagnostic accuracy of MCT with and without dermoscopy and to describe the dermoscopic features of a large series of MCT. METHODS: Dermoscopic images of 161 MCT were evaluated. Clinical and dermoscopic images of histopathologically proven MCT intermingled with other tumors were randomly presented to clinicians with different levels of experience, blinded to the diagnosis and objective of the study. The clinical and dermoscopic diagnostic accuracies were measured separately. RESULTS: A total of 161 histopathologically proven cases of MCT were collected. The most frequent MCT was basal cell carcinoma-seborrheic keratosis collision tumor (CT; 37.9%), followed by basal cell carcinoma-melanocytic nevus CT (19.9%), and melanoma-seborrheic keratosis CT (6.8%). Diagnostic accuracy among experts on dermoscopy was 71.4%. The study included 119 participants. The percentage of correct diagnoses was 8% by naked eye examination and 36.4% by dermoscopy (p < 0.001). The presence of the malignant component in the cases of MCT was not recognizable in 19.1% of cases by naked eye examination and in 11.8% of cases by dermoscopy (p < 0.001). CONCLUSIONS: The diagnosis of MCT can be assisted and clarified by dermoscopy. However, many of these lesions manifest complex morphologies and continue to be challenging, even for experts on dermoscopy. Atypical, uncertain, or non-classifiable lesions still need a complete excision for the final diagnosis.

Dermoscopy of inflamed seborrheic keratosis: A great mimic of malignancy.

BACKGROUND: Clinical and dermoscopic recognition of seborrheic keratoses (SKs) is often straightforward, and biopsy might not be required. However, inflamed SKs (iSKs) can pose a diagnostic challenge. Dermoscopic features of iSKs have not yet been evaluated to date. OBJECTIVES: To assess the diagnostic ability of a group of dermatologists to diagnose iSKs by dermoscopy. To evaluate the dermoscopic findings of a long series of inflamed seborrheic keratoses. METHODS: Clinical and dermoscopic images of 100 difficult-to-diagnose skin tumours, including 29 iSKs, were presented to 33 clinicians (24 dermatologists and 9 dermatology residents), who were blinded to the diagnosis. The dermoscopic features of a series of 219 iSKs were retrospectively analysed. RESULTS: iSKs were correctly identified in a 37.6% of cases. Classic dermoscopic criteria were present in only 47% of iSKs. The most frequent dermoscopic feature in iSKs was the presence of vascularization (91.3%), but only a 44.5% showed predominance of hairpin vessels. A bluish hue was observed in 18.3% of lesions. Seven dermoscopic patterns were identified, based on the dermoscopic similarity to other tumours: seborrheic keratosis-like (28.8%); squamous cell carcinoma-like (25.6%); melanoma-like (17.8%); keratoacanthoma-like (6.8%); basal cell carcinoma-like (5.9%); verruca vulgaris-like (5.9%); nevus-like (2.3%). CONCLUSIONS: The diagnosis of iSKs can be challenging even with dermoscopy. They may behave as authentic mimics of other cutaneous tumours, including squamous cell carcinoma or melanoma. For this reason, histopathological examination should be mandatory in these cases.

Diagnostic accuracy of pigmented labial macules by in vivo reflectance confocal microscopy and correlation among techniques.

BACKGROUND: Pigmented labial macules (PLMs) are clinical, dermoscopic, and histopathologic challenges. OBJECTIVE: To describe and evaluate the utility of reflectance confocal microscopy (RCM) in PLMs and to establish a correlation between dermoscopy, RCM, histopathology, and immunohistochemistry. METHODS: Prospective study of PLMs from 4 tertiary referral dermatology centers. The study included 51 biopsy specimen-proven PLMs. Dermoscopic, RCM images, and histopathologic preparations were evaluated for malignant criteria. Diagnostic accuracy of RCM for melanoma diagnosis, RCM Lip Score previously reported, and κ values between techniques were calculated. RESULTS: Included were 5 melanomas and 46 benign PLMs. Dermoscopically, melanomas exhibited more frequently ≥3 colors and ≥3 structures. With RCM, pagetoid spreading, epithelial disarray, continuous proliferation of atypical cells around papillae, nonhomogeneously distributed papillae, marked cellular atypia, and a higher number of dendritic cells per papillae were more frequent in melanomas. The RCM Lip Score was significantly higher in malignant lesions. Good κ values were observed in most of the evaluated features. A perfect sensitivity and specificity was obtained combining dermoscopy and RCM. LIMITATIONS: A low number of melanomas were obtained. CONCLUSIONS: RCM improves lip melanoma diagnosis, and the RCM Lip Score represents a useful tool for the evaluation of a PLM.

Diagnostic Accuracy of Non-melanocytic Pink Flat Skin Lesions on the Legs: Dermoscopic and Reflectance Confocal Microscopy Evaluation.

Pink flat skin lesions on the legs in elderly people represent a diagnostic challenge due to the paucity of clinical and dermoscopic evidence. A prospective study of 114 pink flat lesions on the legs of 85 elderly patients was performed to describe the utility of reflectance confocal microscopy in this clinical context. Evaluation of clinical, dermoscopic and confocal parameters and calculation of diagnostic accuracy/sensitivity/specificity for non-melanoma skin cancer diagnosis of each technique were carried out. Thirty-four benign and 80 malignant neoplasms were analysed. A correct clinical diagnosis was established in 49.1% of cases (sensitivity 68.7%, specificity 73.5%). Dermoscopy achieved 59.6% correct diagnosis (sensitivity 85%, specificity 67.6%) and confocal microscopy evaluation after clinical and dermoscopic evaluation rendered a correct diagnosis in 85.1% of cases (sensitivity 97.5%, specificity 88.2%). Confocal microscopy may improve diagnostic accuracy, sensitivity and specificity as a secondary evaluation after dermoscopy. A diagnostic confocal algorithm for pink flat lesions on the legs is proposed.

Dermoscopy of arteriovenous tumour: A morphological study of 39 cases.

BACKGROUND/OBJECTIVES: Arteriovenous tumour is a distinct, benign, acquired vascular lesion that can be misdiagnosed. METHODS: A dermoscopic examination of 39 cases of arteriovenous tumours collected from four Spanish hospitals was performed to evaluate specific dermoscopic criteria and patterns. RESULTS: The most common structures found were vascular, 95% of cases (37/39); 90% (35/39) were non-arborising telangiectasia. All the lesions except two (95%) had a homogeneous pigmentation background that was red in 30 cases (77%), bluish-red in three (8%), brown in two (5%) and blue or multicoloured in one case each. Lacunae were seen in only three cases (8%). Non-arborising telangiectasia on a reddish background was identified in 72% of cases. CONCLUSIONS: Dermoscopy is helpful in improving the diagnosis of arteriovenous tumours and allows the observer to differentiate them from other cutaneous lesions such as other vascular tumours, basal cell carcinomas and melanomas.

Multiple progressive annular telangiectasias: A clinicopathological variant of cutaneous collagenous vasculopathy?

Telangiectasias are the clinical manifestation of diverse processes affecting blood vessels. Herein we report the case of a 60-year-old man presenting long-standing asymptomatic annular telangiectatic lesions with whitish centers. The histopathologic examination revealed thickened blood dermal vessel walls in the superficial dermis showing reduplication of the basement membrane resembling cutaneous collagenous vasculopathy (CCV). We suggest that this atypical clinicopathological presentation may represent either a localized annular variant of CCV or a previously unreported clinical form of multiple cutaneous telangiectasias.

Dermoscopy of Adnexal Tumors.

Cutaneous adnexal tumors include lesions with apocrine, eccrine, follicular, sebaceous, and mixed differentiation. Most are benign and sporadic, although malignant forms are occasionally observed and some cases develop in the setting of inherited syndromes. These tumors often cause immense diagnostic difficulty. Dermoscopy is a noninvasive technique that has greatly improved the diagnostic accuracy of different skin lesions, including these tumors. We provide a review of the literature on the dermoscopic structures and patterns associated with adnexal tumors. Most patterns associated with this kind of tumor are nonspecific and are observed in other nonadnexal tumors, especially in basal cell carcinomas.

Histopathologic and Immunohistochemical Correlates of Confocal Descriptors in Pigmented Facial Macules on Photodamaged Skin.

Importance: Pigmented facial macules on photodamaged skin are a clinical, dermoscopic, and histopathologic challenge. Objectives: To clinically and dermoscopically characterize, by means of reflectance confocal microscopy (RCM), ambiguous pigmented facial macules and establish a correlation between RCM, histopathologic, and immunohistochemical findings. Design, Setting, and Participants: A prospective study of ambiguous pigmented facial macules on photodamaged skin was conducted in a tertiary referral center for dermatology between January 1, 2009, and December 31, 2015. Sixty-one patients with 63 ambiguous pigmented facial macules and 12 control photodamaged facial areas were included in the study. Melanocyte density in 1-mm basal layers was determined in skin biopsy specimens from all lesions stained with hematoxylin-eosin and immunohistochemical markers (melan-A, microphthalmia-associated transcription factor, and SRY-related HMG-box gene 10). Dermoscopic, RCM images, and histopathologic preparations were systematically evaluated for the presence of lentigo maligna (LM) criteria. Confocal evaluation was blinded to clinical and dermoscopic diagnosis. Sensitivity and specificity of RCM for LM diagnosis and κ value to establish correlations between dermoscopy, RCM, and histopathology were performed. Main Outcomes and Measures: Sensitivity and specificity of RCM for LM diagnosis. Results: Of the 61 patients included in the study, 31 (51%) were women; mean (SD) age was 71.8 (13.1) years. Twenty-four of the 63 (38%) lesions were diagnosed as LM or LM melanoma (LMM) and 39 (62%) as benign pigmented lesions. Reflectance confocal microscopy enhanced the diagnosis of pigmented facial macules with 91.7% sensitivity and 86.8% specificity. Multivariate analysis showed 2 dermoscopic and 2 confocal features associated with LM or LMM: (1) asymmetric follicular pigmentation and targetlike structures, and (2) round, large pagetoid cells and follicular localization of atypical cells, respectively. Continuous proliferation of atypical melanocytes was found in 21 (88%) LM or LMM and in 3 (77%) benign lesions. Asymmetric pigmented follicular openings by dermoscopy correlated with follicular localization of pagetoid cells by RCM (κ = 0.499, P < .001). The presence of 3 or more atypical cells at the dermal-epidermal junction (DEJ) by RCM correlated with hyperplasia of melanocytes in hematoxylin-eosin sections (κ = 0.422, P < .001). Conclusions and Relevance: Reflectance confocal microscopy improves LM diagnosis in photodamaged skin with good histopathologic correlation although false-positive and false-negative cases exist. False-positives obtained with RCM in photodamaged skin are due to the presence of basal melanocyte hyperplasia and intraepidermal Langerhans cells. Histopathologic features of these lesions sometimes are not enough for a definite diagnosis and immunohistochemical studies may be required.

Persistent cutaneous abdominal ulcerations secondary to diffuse dermal angiomatosis: an underestimated sign for severe atherosclerosis: A case report.

BACKGROUND: Diffuse dermal angiomatosis (DDA) is a rare, acquired, reactive vascular proliferation, clinically characterized by livedoid erythematous-violaceous plaques, which frequently evolve to ulceration and necrosis. Histopathologically, it is manifested by a diffuse proliferation of endothelial cells within the full thickness of the dermis. DDA has been mainly associated with severe peripheral atherosclerosis. METHODS: We report a 63-year-old woman who presented with multiple erythematous-violaceous plaques with central deep skin ulcers on thighs, lower abdomen, and perianal area, associated with intermittent claudication, low-grade fever, and weight loss. Initially, the clinical picture along with positive cultures for Klebsiella pneumoniae suggested a multifocal ecthyma gangrenosum; nevertheless, a skin biopsy showed a diffuse dermal proliferation of endothelial cells interstitially arranged between collagen bundles. A computed tomography scan revealed severe aortic atheromatosis with complete luminal occlusion of the infrarenal aorta and common iliac arteries. RESULTS: The diagnosis of DDA secondary to severe atherosclerosis was established. The patient underwent a left axillofemoral bypass surgery with a rapidly healing of the ulcers in the next weeks. CONCLUSIONS: DDA should be considered in the differential diagnosis of livedoid ischemic lesions. Recognition of DDA as a cutaneous sign of severe peripheral vascular disease is important for both dermatologists and internists. Recognition of risk factors and their management with an early intervention to correct tissue ischemia can be curative.