Die Bedeutung der blauen Farbe in der Dermatoskopie.

HINTERGRUND UND ZIELE: Hautläsionen mit blauer Färbung werden häufig chirurgisch entfernt, um Malignität auszuschließen zu können. Das Ziel der vorliegenden Studie war es, die Bedeutung der blauen Färbung zu untersuchen. METHODEN: Wir untersuchten dermatoskopische Bilder retrospektiv auf blaue Farbe und klassifizierten sie gemäß der Musteranalyse. ERGEBNISSE: Von 1.123 pigmentierten Hautläsionen wiesen 144 (12,8 %) eine blaue Färbung auf. Von diesen waren 92 (63,9 %) bösartig. Unter den Läsionen mit Blaufärbung waren Nävi (n = 35, 24,3 %) und seborrhoische Keratosen (n = 8, 5,6 %) die häufigsten gutartigen Diagnosen. Von 103 (71,5 %) Läsionen mit einem strukturlosen blauen Muster waren acht (7,8 %) vollständig blau gefärbt und 95 (92,2 %) teilweise blau, davon zeigten 81 (78,6 %) periphere oder fleckige und 14 (13.6 %) eine zentrale Blaufärbung. Die meisten Läsionen mit peripherer oder fleckiger blauer Färbung waren Melanome (n = 47, 58 %), wohingegen die meisten Läsionen mit zentraler Blaufärbung Nävi darstellten (n = 9, 64,3 %). Von 28 Läsionen mit blauen Schollen waren 17 (60,7 %) Basalzellkarzinome. Bezüglich der Malignität war der positive prädiktive Wert der blauen Farbe 63,9 % (95 % KI: 56,0-71,8 %). SCHLUSSFOLGERUNGEN: Unter blaugefärbten bösartigen Läsionen ist eine strukturlose periphere oder fleckige blaue Farbe ein Hinweis auf Melanome, während blaue Schollen auf ein Basalzellkarzinom hinweisen. Als Fallstricke können sich seborrhoische Keratosen erweisen, die eine Blaufärbung zeigen können, sowie einige Nävi, vor allem kombinierte.

The significance of blue color in dermatoscopy.

BACKGROUND AND OBJECTIVES: Skin lesions with blue color are frequently excised to rule out malignancy. The objective of the present study was to investigate the significance of blue color. METHODS: We retrospectively scanned dermatoscopic images for blue color and classified them according to pattern analysis. RESULTS: Of 1,123 pigmented skin lesions, 144 (12.8 %) showed blue color, 92 of which (63.9 %) were malignant. Among lesions with blue color, the most common benign diagnoses were nevi (n = 35, 24.3 %) and seborrheic keratoses (n = 8, 5.6 %). Of 103 (71.5 %) lesions with a structureless blue pattern, eight (7.8 %) were entirely blue and 95 (92.2 %) were partly blue, of which 81 (78.6 %) showed peripheral or patchy and 14 (13.6 %) central blue color. Most lesions with peripheral or patchy blue color were melanomas (n = 47, 58 %), whereas most lesions with central blue color were nevi (n = 9, 64.3 %). Of 28 lesions with blue clods, 17 (60.7 %) were basal cell carcinomas. With respect to malignancy, the positive predictive value of blue color was 63.9 % (95 % CI: 56.0-71.8 %). CONCLUSIONS: Among malignant lesions with blue color, structureless peripheral or patchy blue color is a clue for melanoma, while blue clods point to basal cell carcinoma. Pitfalls include seborrheic keratoses, which may show blue color, as well as some nevi, especially combined nevi.

Statistical evaluation of dermoscopic features in basal cell carcinomas.

BACKGROUND: Early detection of basal cell carcinoma (BCC) is of crucial importance, as serious morbidity may result from undiagnosed tumor. OBJECTIVE: To evaluate diagnostic significance (specificity, sensitivity, positive and negative predictive value) of dermoscopic features in BCCs. METHODS: A prospective observational study was conducted using contact polarized dermoscopy to evaluate the presence of various dermoscopic features. Images were evaluated for a range of dermoscopic colors, structures, and vessels. SETTING: Specialized University Clinic. PATIENTS: A sample of 151 histopathologically verified BCCs was collected from 116 patients (64 males and 52 females). The populations included predominantly Caucasian individuals. MAIN OUTCOME MEASURES: The sensitivity, specificity, positive and negative predictive values of the various dermoscopic features seen in BCCs were calculated according to standard formulas. RESULTS: The highest diagnostic value (specificity [Sp] = 100%, positive predictive value [PPV] = 100%) for BCC had spoke-wheel areas, short fine telangiectasias, white rosette, annular hypopigmentation, multiple erosions, and ulceration. Arborizing vessels (Sp = 96%, PPV = 98%) and microvessels (Sp = 93%, PPV = 97%) had significant diagnostic value for BCC. Annular distribution of telangiectatic vessels (Sp = 96%), translucency (Sp = 93%), and multiple blue-gray globules (Sp = 89%) had the same PPV of 95% for BCCs. Other dermoscopic features of this study are not strongly associated with the diagnosis of BCC. CONCLUSION: Dermoscopic features relevant for diagnosis of BCC have different diagnostic "weight." Clinicians should have known the sensitivity and specificity of each relevant feature before they can make an accurate dermoscopic diagnosis of BCC.

Dermoscopic features in different morphologic types of basal cell carcinoma.

BACKGROUND: Many different phenotypic presentations of basal cell carcinoma (BCC) are possible. OBJECTIVE: This study aims to highlight the similarities and differences in dermoscopic features between different morphologic types of BCC. METHODS: A prospective observational study was performed using contact polarized dermoscopy to evaluate the presence of various dermoscopic features. Images were evaluated for a range of dermoscopic colors, structures, and vessels. Features were compared according to the histopathologic subtype. RESULTS: Of the 151 BCCs, 39.7% were nodular, 37.7% superficial, 13.9% ulcerated, 3.97% pigmented, 2.65% morpheaform, and 1.99% infiltrative BCCs. The dermoscopic features that showed a highly significant difference (p < .001) in distribution between various histologic groups were large blue-gray ovoid nests, leaf-like areas, arborizing vessels, short fine telangiectasias, annular distribution of telangiectatic vessels, structureless hypopigmentation, annular hypopigmentation, translucency, multiple erosions, and ulceration. A significant difference (p < .05) between evaluated groups was found in structureless hyperpigmentation, arborizing microvessels, milky red background, and pigment network. CONCLUSION: The results of the study indicate that the combination of relevant dermoscopic features in different morphologic types of BCC depends on the thickness of the tumor, and not on its histologic nature. In addition, dermoscopy was shown to be not particularly useful in identifying which BCCs are more aggressive.

Vertical Ex Vivo Dermoscopy in Assessment of Malignant Skin Lesions.

The role of vertical ex vivo dermoscopy relevant to clinical diagnosis has not been investigated yet. Study objectives were defining, describing, and determining the importance of the structures visible using vertical ex vivo dermoscopy in the diagnosis of malignant skin lesions, as well as determining their accuracy in the assessment of tumor margins. A prospective, descriptive study was conducted in two University centers. Digital images of completely excised skin lesions, fixed in formalin, before histopathological diagnosis were used for analysis. BCCs had the most diverse dermoscopic presentation on the vertical section, while SCCs showed a similar presentation in most cases. Vertical dermoscopy of thin melanomas was almost identical, unlike nodular melanomas. Thickness accuracy assessed by dermatologist was 0.753 for BCC, 0.810 for SCC, and 0.800 for melanomas, whereas assessment by pathologist was 0.654, 0.752, and 0.833, respectively. The accuracy of tumor width assessment was 0.819 for BCCs, 0.867 for SCCs and 1.000 for melanoma as estimated by a Dermatologist. Interobserver agreement was 0.71 for BCC, 0.799 for SCC and 0.832 for melanomas. Vertical ex vivo dermoscopy may contribute to the distinction between BCCs, SCCs, and melanomas. Moreover, regardless of the doctor's specialty, it enables a good assessment of the tumor's margins.

The use of dermoscopy in distinguishing the histopathological subtypes of basal cell carcinoma: A retrospective, morphological study.

Background The role of dermoscopy in distinguishing the histopathological subtypes of basal cell carcinoma (BCC) is not fully elucidated. Aims To determine the accuracy of dermoscopy in diagnosing different BCC subtypes. Methods The dermoscopic features of 102 histopathologically verified BCCs were studied retrospectively. The tumours were classified as superficial (n=33,32.3%), nodular (n=46,45.1%) and aggressive (n=23,22.6%) BCCs by histopathology. Statistical analysis included Cohen's kappa test, proportion of correlation, measures of diagnostic accuracy, diagnostic odds ratio and the credibility ratio of positive (LR+) and negative (LR-) tests. Results The highest value in all performed tests was seen in superficial BCCs (kappa 0.85; proportion of correlation 93%; diagnostic accuracy 93.1%), good correlation was noted in nodular BCCs (kappa 0.62, proportion of correlation 80%; diagnostic accuracy 80.4%) but dermoscopic correlation with histopathology was low for aggressive BCCs (kappa 0.13; proportion of correlation 79%; diagnostic accuracy 78.4%). Short, fine telangiectasias (83.3%) showed the greatest importance for the diagnosis of superficial BCCs, blue-grey ovoid nests (61.8%) had the highest diagnostic accuracy in nodular BCCs, while arborising vessels (79.4%) was the most significant dermoscopic feature for the diagnosis of aggressive BCCs. Limitations This was a retrospective analysis and included only Caucasian patients from a single centre. Conclusion The highest agreement of dermoscopic features with the histologic type was found in superficial BCCs. We did not find any specific dermoscopic structure that could indicate a diagnosis of aggressive BCC. The presence of relevant dermoscopic features in the evaluated cases was determined by the depth of tumour invasion and not by its histology.