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Background: Nonpigmented skin cancer is common, and diagnosis with the unaided eye is error prone.Objective: To investigate whether dermatoscopy improves the diagnostic accuracy for nonpigmented (amelanotic) cutaneous neoplasms.Methods: We collected a sample of 2072 benign and malignant neoplastic lesions and inflammatory conditions and presented close-up images taken with and without dermatoscopy to 95 examiners with different levels of experience.Results: The area under the curve was significantly higher with than without dermatoscopy (0.68 vs 0.64, P < .001). Among 51 possible diagnoses, the correct diagnosis was selected in 33.1% of cases with and 26.4% of cases without dermatoscopy (P < .001). For experts, the frequencies of correct specific diagnoses of a malignant lesion improved from 40.2% without to 51.3% with dermatoscopy. For all malignant neoplasms combined, the frequencies of appropriate management strategies increased from 78.1% without to 82.5% with dermatoscopy.Limitations: The study deviated from a real-life clinical setting and was potentially affected by verification and selection bias.Conclusions: Dermatoscopy improves the diagnosis and management of nonpigmented skin cancer and should be used as an adjunct to examination with the unaided eye. [ABSTRACT FROM AUTHOR]

We describe two algorithms to diagnose basal cell carcinomas (BCCs) and melanomas (MMs) using in vivo reflectance confocal microscopy (RCM). A total of 710 consecutive cutaneous lesions excised to exclude malignancy (216 MMs, 266 nevi, 119 BCCs, 67 pigmented facial macules, and 42 other skin tumors) were imaged by RCM. RCM features were correlated with pathology diagnosis to develop diagnostic algorithms. The diagnostic accuracy of the BCC algorithm defined on multivariate analysis of the training set (50%) and tested on the remaining cases was 100% sensitivity, 88.5% specificity. Positive features were polarized elongated features, telangiectasia and convoluted vessels, basaloid nodules, and epidermal shadowing corresponding to horizontal clefting. Negative features were non-visible papillae, disarrangement of the epidermal layer, and cerebriform nests. Multivariate discriminant analysis on the training set (excluding the BCCs) identified seven independently significant features for MM diagnosis. The diagnostic accuracy of the MM algorithm on the test set was 87.6% sensitivity, 70.8% specificity. The four invasive MMs that were misdiagnosed by RCM were all of nevoid subtype. RCM is a highly accurate non-invasive technique for BCC diagnosis. Good diagnostic accuracy was achieved also for MM diagnosis, although rare variants of melanocytic tumors may limit the strict application of the algorithm. [ABSTRACT FROM AUTHOR]

Background: Early detection of basal cell carcinoma (BCC) is crucial to reduce the morbidity of this tumor. Objective: We sought to investigate the variability and diagnostic significance of dermatoscopic features of BCCs. Methods: We conducted retrospective dermatoscopic analysis of 609 BCCs and 200 melanocytic and nonmelanocytic lesions, and assessment of interrater reliability of dermatoscopic BCC criteria. Results: Lesions included nonpigmented (15.1%), lightly pigmented (33.2%), pigmented (42.7%), and heavily pigmented (9%) BCCs. Classic BCC patterns including arborizing telangiectasia (57.1%), blue/gray ovoid nests (47.5%), ulceration (39.2%), multiple blue/gray globules (26.1%), leaflike areas (15.9%), and spoke-wheel areas (9%) were significantly increased in pigmented BCCs compared with nonpigmented and heavily pigmented BCCs (P = .0001). Among nonclassic BCC patterns, we detected short fine superficial telangiectasia (10%) and multiple small erosions (8.5%), and described two new patterns named “concentric structures” (7.6%) and “multiple in-focus blue/gray dots” (5.1%). Dermatoscopic features suggestive of melanocytic lesions (eg, multiple brown to black dots/globules, blue/white veillike structures, and nonarborizing vessels) were observed in 40.6% BCCs and significantly increased in heavily pigmented BCCs (P < .0001). Expert observers provided an accurate (sensitivity: 97%) and reliable (K: 87%) dermatoscopic diagnosis of BCC, although a significant difference in terms of specificity (P = .0002) and positive predictive value (P = .0004) was found. Arborizing telangiectasia, leaflike areas, and large blue/gray ovoid nests represented reliable and robust diagnostic parameters. Limitation: The study was retrospective. Conclusion: BCCs show a large spectrum of global and local dermatoscopic features; heavily pigmented BCCs show the most challenging combinations of dermatoscopic features. [Copyright &y& Elsevier]

Background: Spitz nevi are benign melanocytic tumors, sometimes misdiagnosed as malignant melanoma (MM). Objective: We sought identification of characteristic in vivo microscopic features of Spitz nevi, their histopathologic correlates, and diagnostic usefulness. Methods: Forty Spitz nevi were studied by in vivo confocal microscopy and dermatoscopy, evaluating histopathologic correlates, and compared with 40 MMs and 40 Clark nevi. Results: Some histologic aspects characteristic for Spitz nevus diagnosis were correlated with confocal features, comprising some that can be useful for atypical Spitz nevus classification. The most striking features for differentiating Spitz nevi from MMs were the presence of sharp border cut-off, junctional nests, and melanophages. Limitations: No correlates were found for other aspects, such as Kamino bodies, hyperkeratosis, acanthosis, mitoses, and maturation with depth. The impossibility of exploring deeper aspects hampered an accurate distinction from MMs in some cases. Conclusion: Confocal and dermatoscopic examination enabled the identification of different Spitz categories with different histologic substrates. [Copyright &y& Elsevier]

We have previously described a guinea-pig model where pigmented nevi similar to human nevi can be produced by application of low-dose topical 7,12-dimethylbenzanthracene (DMBA) followed by solar-simulated light. Five groups of guinea-pigs were used to test the effect of various spectral bands of solar-simulated light on low-dose DMBA-induced melanocytic nevi. Animals were irradiated with either UVB to near UVA2 (290–325 nm), UVA, visible light, full solar spectrum or no irradiation three times per wk for 12 mo to determine the broad-band effect of nevi-inducing irradiation. There was a significant increase in nevi/animal in the UVB-treated group (mean 1.53) compared with all groups ( versus UVA 0.3, p<0.001; versus visible light 0.24, p<0.001; versus full spectrum (UVB+UVA+visible) 0.68, p=0.02; versus control (nil irradiation) 0.37, p=0.01). No differences in skin thickness were found between any group (p=0.11). In conclusion, we present a report of the active waveband of melanocytic nevi induction; where UVB to near UVA2 is the likely responsible waveband. Furthermore, because there was a significant decrease in nevi/animal receiving the full solar spectrum compared with the UVB group, it is possible that broad-band UVA and or visible light may be inhibitory wavebands for nevi induction. [ABSTRACT FROM AUTHOR]

Abstract: In previous research, a watershed-based algorithm was shown to be useful for automatic lesion segmentation in dermoscopy images, and was tested on a set of 100 benign and malignant melanoma images with the average of three sets of dermatologist-drawn borders used as the ground truth, resulting in an overall error of 15.98%. In this study, to reduce the border detection errors, a neural network classifier was utilized to improve the first-pass watershed segmentation; a novel “edge object value (EOV) threshold” method was used to remove large light blobs near the lesion boundary; and a noise removal procedure was applied to reduce the peninsula-shaped false-positive areas. As a result, an overall error of 11.09% was achieved. [Copyright &y& Elsevier]

Limited studies have reported the in vivo reflectance confocal microscopy (RCM) features of lentigo maligna (LM). A total of 64 RCM features were scored retrospectively and blinded to diagnosis in a consecutive series of RCM sampled, clinically equivocal, macules of the face (n=81 LM, n=203 benign macules (BMs)). In addition to describing RCM diagnostic features for LM (univariate), an algorithm was developed (LM score) to distinguish LM from BM. This comprised two major features each scoring +2 points (nonedged papillae and round large pagetoid cells >20 μm), and four minor features; three scored +1 point each (three or more atypical cells at the dermoepidermal junction in five 0.5 × 0.5 mm2 fields, follicular localization of atypical cells, and nucleated cells within the dermal papillae), and one (negative) feature scored −1 point (a broadened honeycomb pattern). A LM score of 2 resulted in a sensitivity of 85% and specificity of 76% for the diagnosis of LM (odds ratio (OR) for LM 18.6; 95% confidence interval: 9.3–37.1). The algorithm was equally effective in the diagnosis of amelanotic lesions and showed good interobserver reproducibility (87%). In a test set of 29 LMs and 44 BMs, the OR for LM was 60.7 (confidence interval: 11.9–309) (93% sensitivity, 82% specificity). [ABSTRACT FROM AUTHOR]

We recently described an in vivo reflectance confocal microscopy (RCM) method and our aim was to evaluate a possible additive value of this type of analysis in the management of melanocytic lesions. In two referral centers (Sydney and Modena), lesions (203 nevi and 123 melanomas (MMs) with a median Breslow thickness of 0.54 mm) were excised on the basis of clinical suspicion (history, dermoscopy examination, and/or digital monitoring). The RCM method was also trialed on a non-biopsied population of 100 lesions, which were clinically and dermoscopically diagnosed as benign nevi. All RCM and dermoscopy diagnoses were performed blinded to the histopathological diagnosis. Firstly, in the study population, a high interobserver agreement (on a subset of 90 lesions) was seen with the RCM method, which had superior specificity (68%, 95% confidence interval (95% CI): 61.1–74.3) for the diagnosis of MM compared with dermoscopy (32%, 95% CI: 25.9–38.7), while showing no difference in sensitivity (91%, 95% CI: 84.6–95.5, RCM; 88%, 95% CI: 80.7–92.6 dermoscopy). The two techniques had a weak correlation, resulting in only 2.4% of MMs being misclassified by both techniques. Diagnosis of light-colored lesions is improved by RCM (specificity 84%, 95% CI: 66.3–94.5) compared with dermoscopy (specificity 39%, 95% CI: 23.7–56.2). Secondly, the RCM method classified 100% of the non-biopsied control nevi population as benign.Journal of Investigative Dermatology (2009) 129, 131–138; doi:10.1038/jid.2008.193; published online 17 July 2008 [ABSTRACT FROM AUTHOR]