Surveillance of patients at high risk for cutaneous malignant melanoma using digital dermoscopy

BACKGROUND: Dermoscopy has improved the sensitivity and specificity of clinical diagnosis of melanoma from 60% to over 90%. However, in order not to miss melanoma a certain percentage of suspicious but benign lesions has to be excised. OBJECTIVES: To evaluate the dermoscopic changes and the rates of excision in benign melanocytic naevi and cutaneous malignant melanoma in long-term follow-up of high-risk patients using digital dermoscopy. METHODS: Digital dermoscopic images of 2015 atypical melanocytic naevi in 196 high-risk patients were analysed retrospectively. Among others, the following data were collected for each naevus: changes in surface area, overall architecture, dermoscopic patterns and distribution of pigmentation. All tumours suspicious for melanoma or showing asymmetrical changes were excised. RESULTS: During a median follow-up time of 25 months 128 (6.4%) of all naevi showed changes in size or architecture. Eighty-six per cent of all changes in patients who attended more than one visit were observed at the first follow-up visit. Thirty-three lesions showing changes were excised and two melanomas in situ and 31 melanocytic naevi were diagnosed. CONCLUSIONS: Follow-up examinations using digital dermoscopy revealed unchanged morphology in the large majority of melanocytic naevi. Excisions were only performed in cases of asymmetrical growth, asymmetrical changes of pigmentation, or development of dermoscopic features indicative of melanoma. The ratio of 33 lesions excised in order to identify two melanomas in situ seems reasonable and may be further reduced in future.     

Asymmetry in dermoscopic melanocytic lesion images: a computer description based on colour distribution

Digital dermoscopy improves the accuracy of melanoma diagnosis. The aim of this study was to develop and validate software for assessment of asymmetry in melanocytic lesion images, based on evaluation of colour symmetry, and to compare it with assessment by human observers. An image analysis program enabling numerical assessment of asymmetry in melanocytic lesions, based on the evaluation and comparison of CIE L*a*b* colour components (CIE L*a*b* is the name of a colour space defined by the Commission Internationale de l'Eclairage) inside image colour blocks, was employed on the recorded lesion images. Clinical evaluation of asymmetry in dermoscopic images was performed on the same image set employing a 0-1 scoring system. Asymmetry judgement was expressed by the clinicians for 12.8% of benign naevi, 44.7% of atypical naevi and 64.2% of malignant melanomas, whereas the computer identified as asymmetric 6.3%, 33.3% and 82.2%, respectively. Numerical parameters referring to malignant melanomas were significantly higher, both with respect to benign naevi and atypical naevi. The numerical parameters produced could be effectively employed for computer-aided melanoma diagnosis.     

Value of the clinical history for different users of dermoscopy compared with results of digital image analysis

BACKGROUND: The clinical history of a given pigmented lesion could influence the therapeutic decision. Teledermatology and automated image analysis also hold great potential for revolutionizing dermatology services. AIM: The aim of this retrospective study was to evaluate the diagnostic accuracy of users with different experiences in dermoscopy with and without information about patients and their history compared with classification by an automated analysing system. SETTING: One hundred and fifty-seven dermoscopic images of pigmented lesions, taken and proved by histopathology at the Pigmented Lesions Clinic of the Department of Dermatology of the University Tuebingen, Germany, were included. METHODS: All images were viewed by three investigators with different experience: excellent (A), average (B) and beginner (C). In the first dermoscopic classification, no information was available. After 3 months the same images were once more classified by the three investigators, now with the information about the patients and their history. The melanocytic lesions were tested by the Tuebinger Mole Analyser. RESULTS: For user A the sensitivity, specificity and diagnostic accuracy revealed no improvement on including the history (81.3% to 84.4%, 94.6% to 92.3% and 92.0% to 90.7%), whereas user B clearly improved his results (75.0% to 87.5%, 76.9% to 88.5% and 76.5% to 88.3%). No change in the sensitivity was seen by user C (84.4%), but there was a clear improvement in the specificity (69.2% to 87.7%) and diagnostic accuracy (72.2% to 87.0%). Using the computer algorithm, a sensitivity of 100%, a specificity of 76.9% and a diagnostic accuracy of 81.9% were achieved. CONCLUSIONS: The study revealed results relevant to the use of dermoscopy: (1) continuing dermoscopic education influences the diagnostic accuracy; (2) the history is helpful for averaged users and beginners in dermoscopy; (3) digital image analysis has the highest sensitivity, but a lower specificity compared to the clinicians; and (4) digital dermoscopy could be used for store-and-forward systems in teledermoscopy.     

The role of pattern analysis and the ABCD rule of dermoscopy in the detection of histological atypia in melanocytic naevi

BACKGROUND: Clinical features of melanocytic naevi correlate poorly with the presence, histopathologically, of architectural disorder and cytological atypia, making the detection of histological atypia by means of macroscopic appearance unreliable. OBJECTIVES: The aim of this study was to investigate the diagnostic effectiveness of dermoscopy in the non-invasive detection of histological atypia in naevi. METHODS: Observers blinded for histological diagnosis classified a series of 168 melanocytic naevi as common or atypical on the basis of their clinical features and on their dermoscopic profile. The diagnostic performance of both methods compared with the true (histopathological) diagnosis was assessed. RESULTS: Dermoscopy using pattern analysis showed better results than clinical examination in the non-invasive detection of naevi with architectural disorder with or without cytological atypia (diagnostic accuracy 45% vs. 28%). A statistically significant difference in the frequency of dermoscopic parameters between atypical and common naevi was found for atypical pigment network (39% vs. 17%, P = 0.001) and dermoscopic regression structures (13% vs. 2%, P = 0.008). Dermoscopic features, which best predicted histological atypia in naevi, were regression structures (white scar-like areas or peppering), irregular vascular pattern and grey-blue areas (positive predictive values 83%, 83% and 73%, respectively). In contrast, no statistically significant difference in the mean values of the ABCD score between common and atypical naevi was found. The best diagnostic performance of dermoscopy by means of the ABCD rule (cut-off point of 4.0 of total dermoscopy score) was not dissimilar to that of clinical diagnosis (diagnostic accuracy 30%). CONCLUSIONS: Dermoscopy by means of pattern analysis enhances the diagnostic accuracy of dermatologists in the prediction of histological atypia in melanocytic naevi as compared with clinical examination alone.     

Limitations of dermoscopy in the recognition of melanoma

OBJECTIVE: To compare dermoscopic features of melanocytic nevi with those of early melanomas that were not excised initially because of their uncharacteristic clinical and dermoscopic appearance. DESIGN: Retrospective study of the baseline images of 325 melanocytic skin lesions that were observed by digital dermoscopy and finally excised because of changes over time. SETTING: A dermatologic clinic and a dermatologic department at a university hospital. MAIN OUTCOME MEASURES: Comparison of baseline images of melanomas and melanocytic nevi by pattern analysis, the ABCD rule of dermoscopy, and the 7-point checklist. RESULTS: Baseline dermoscopic images of 262 melanocytic nevi and 63 melanomas from 315 patients were included in the analysis. The patterns of dermoscopic features observed in the baseline images of melanocytic lesions finally diagnosed as melanomas during follow-up did not differ substantially from the patterns observed in the baseline images of melanocytic nevi. Pattern analysis, the ABCD rule of dermoscopy, and the 7-point checklist failed to achieve adequate diagnostic accuracy for melanoma. In retrospect, no dermoscopic feature or pattern of features could be identified that reliably differentiated between melanomas and melanocytic nevi at the time of the first presentation. CONCLUSION: Dermoscopy depends on the appearance of classic dermoscopic features and is therefore limited in the diagnosis of very early and mainly featureless melanomas.     

Mobile teledermatology for skin tumour screening: diagnostic accuracy of clinical and dermoscopic image tele-evaluation using cellular phones

Background The ability to diagnose malignant skin tumours accurately and to distinguish them from benign lesions is vital in ensuring appropriate patient management. Little is known about the effects of mobile teledermatology services on diagnostic accuracy and their appropriateness for skin tumour surveillance. Objectives To evaluate the diagnostic accuracy of clinical and dermoscopic image tele‐evaluation for mobile skin tumour screening. Methods Over a 3‐month period up to three clinical and dermoscopic images were obtained of 113 skin tumours from 88 patients using a mobile phone camera. Dermoscopic images were taken with a dermatoscope applied to the camera lens. Clinical and dermoscopic images of each lesion together with clinical information were separately teletransmitted for decision‐making. Results were compared with those obtained by face‐to‐face examination and histopathology as the gold standard. Results A total of 322 clinical and 278 dermoscopic images were acquired; two (1%) clinical and 18 (6%) dermoscopic pictures were inadequate for decision‐making. After excluding inadequate images, the majority of which were dermoscopic pictures, only 104 of the 113 skin tumours from 80 of 88 patients could be tele‐evaluated. Among these 104 lesions, 25 (24%) benign nonmelanocytic, 15 (14%) benign melanocytic, 58 (56%) malignant nonmelanocytic and six (6%) malignant melanocytic lesions were identified. Clinical and dermoscopic tele‐evaluations demonstrated strong concordance with the gold standard (κ = 0·84 for each) and similar high sensitivity and specificity for all diagnostic categories. With regard to the detailed diagnoses, clinical image tele‐evaluation was superior to teledermoscopy resulting in 16 vs. 22 discordant cases. Conclusions Clinical image tele‐evaluation might be the method of choice for mobile tumour screening.     

Modified dermoscopic algorithm for the differentiation between melanocytic and nonmelanocytic skin tumors

BACKGROUND: The use of dermoscopy (dermatoscopy, epiluminescence microscopy, surface microscopy) improves the clinical diagnostic accuracy of skin tumors by applying different algorithms or scores. The first step in the dermoscopic evaluation is the differentiation between melanocytic and nonmelanocytic skin tumors. OBJECTIVE: To evaluate the diagnostic accuracy of the established dermoscopic algorithm (EDA) and the modified dermoscopic algorithm (MDA) for melanocytic versus nonmelanocytic skin tumors. METHODS: Two hundred forty-nine patients with melanocytic and nonmelanocytic skin lesions were included. Dermoscopic images of the tumors were taken with 10-fold magnification, followed by surgery and histopathology at the departments of Dermatology at the universities of Tuebingen, in Germany, and Naples, in Italy. Each lesion was classified using the EDA and MDA. In the MDA, accessory nipples and dermatofibromas were considered in particular. RESULTS: With the EDA, 225 of 249 (90.4%) skin tumors were correctly classified in one of the six groups. With the MDA, 237 of 249 (95.2%) were correctly classified. Improvement was achieved in 12 (4.8%) better classified skin tumors. In both algorithms, no melanoma was classified as a nonmalignant melanocytic tumor. All melanomas were classified in the group of melanocytic tumors and one melanoma was classified in the group of basal cell carcinomas. CONCLUSION: Both dermoscopic algorithms for the differentiation between melanocytic and nonmelanocytic skin tumors were simple and effective when applied step by step. The MDA is an improvement on the EDA with the classification of accessory nipples and dermatofibromas.     

Dermoscopy of skin lesions in two patients with xeroderma pigmentosum

BACKGROUND: Xeroderma pigmentosum (XP) is a rare disorder produced by a genetic defect in the repair of DNA damage caused by ultraviolet radiation. The early diagnosis of malignant skin tumours is crucial in the survival of patients with XP, but this is not easy even for experienced dermatologists due to the presence of a high number of actinic lesions. Dermoscopy is a new diagnostic method that increases the diagnostic accuracy for skin tumours. OBJECTIVES: To describe the clinical and dermoscopic features of different benign and malignant lesions [focusing on malignant melanoma, basal cell carcinoma (BCC) and benign melanocytic naevi] in two patients with XP. METHODS: Three dermatologists with experience in pigmented skin lesions and dermoscopy examined two siblings with XP over a period of 54 months. Diagnosis of skin tumours was obtained using clinical examination and dermoscopy with 10-fold magnification and digital images. All the tumours with criteria of malignancy were excised for further histopathological analyses. RESULTS: Multiple skin tumours showing some degree of pigmentation were detected in the patients. Clinical and dermoscopic examination allowed the discrimination of four melanomas (three of them in situ), 26 BCCs and five dysplastic naevi from other pigmented skin lesions. The features and parameters previously described for dermoscopy were shown to be appropriate for the recognition of tumours in our patients with XP. Generalized actinic lentigos were distinguished from BCCs by the presence of a delicate brown pigmented network. Fine vessels from poikiloderma were differentiated from the arborizing telangiectasia of BCC. CONCLUSIONS: The dermoscopic findings in the tumours were similar to those previously described in patients not affected by XP. Diagnosis by dermoscopic pattern analyses allowed a correct classification of malignant tumours in these cases.     

Dermoscopic patterns of benign volar melanocytic lesions in patients with atypical mole syndrome

BACKGROUND: Acral benign melanocytic lesions in white populations, particularly in subjects with atypical mole syndrome, have been poorly characterized until recently. The advent of dermoscopy has enabled more specific diagnoses of these pigmented skin lesions. OBJECTIVE: To evaluate the clinical and dermoscopic features of benign volar lesions in a group of white patients with atypical mole syndrome. SETTING: A private medical center specializing in early diagnosis of malignant melanoma and a melanoma unit in a university hospital. METHODS: Acral melanocytic lesions in 511 patients with atypical mole syndrome were studied using standard clinical assessment and dermoscopy. RESULTS: Two hundred ten acral melanocytic lesions were observed in 156 of the patients: 165 lesions were present on the soles of 121 patients and 45 lesions on the palms of 35 patients. No acral malignant lesions were detected. We observed the following patterns of lesions: parallel furrow in 111 lesions (52.9%), latticelike in 26 lesions (12.4%), fibrillar or filamentous in 13 lesions (6.2%), and nontypical in 29 lesions (13.8%). In 31 lesions (14.8%), we observed 3 previously undefined patterns: a globular pattern in 11 lesions (5.2%), a homogeneous pattern in 15 lesions (7.1%), and an acral reticular pattern in 5 lesions (2.4%). CONCLUSIONS: We observed a greater number of benign melanocytic lesions in glabrous skin than expected, probably related to our cohort selection of patients with atypical mole syndrome, although the lesions generally exhibited patterns on dermoscopy similar to those seen in Japanese studies. We defined 3 new benign dermoscopic patterns, which will enable better characterization of acral lesions.     

Can automated dermoscopy image analysis instruments provide added benefit for the dermatologist? A study comparing the results of three systems

BACKGROUND: Instruments designed to provide computer program-driven diagnosis of dermoscopic images of lesions are now commercially available. Multiple publications tout the improved diagnostic accuracy of these instruments compared with that of clinicians. OBJECTIVES: Our aim was to evaluate the actual usefulness of these instruments for dermatologists practising in a pigmented lesion clinic. METHODS: Over a 4-month period we subjected lesions, which were being evaluated in one of our clinics, to automated computer diagnosis performed by three commercially available instruments. We intentionally included three groups of lesions: group 1 lesions were suspicious melanocytic lesions that were scheduled to be excised; group 2 lesions were nonmelanocytic lesions; group 3 lesions were clinically obvious melanomas. The automated diagnoses provided by the instruments were compared with the dermoscopy diagnosis of experienced physicians and with histopathology. RESULTS: We included a total of 107 lesions. One imaging system's computer algorithm was unable to analyse one third of the lesions. All three instruments' computer algorithms were able to identify the clinically obvious melanomas (group 3) correctly. However, all three systems tended to overdiagnose by incorrectly classifying most seborrhoeic keratoses (group 2) as potential malignant lesions. Concerning the suspect melanocytic lesions (group 1), which are precisely the lesions for which a dermatologist would welcome a second opinion, we found significant variability in the diagnostic accuracy of the instruments tested. However, all three systems providing computer-assisted diagnosis had a tendency to overdiagnose benign melanocytic lesions as potential melanomas. CONCLUSIONS: Although the image analysis systems tested by us correctly identified the clinically obvious melanomas, they were not able to discriminate between most dysplastic naevi and early malignant melanoma. Thus, for the moment these computer-assisted diagnostic imaging machines provide little to no added benefit for the experienced dermatologist/dermoscopist.     

Modified ABC-point list of dermoscopy: A simplified and highly accurate dermoscopic algorithm for the diagnosis of cutaneous melanocytic lesions

BACKGROUND: The use of dermoscopy (epiluminescence microscopy, surface microscopy, dermatoscopy) improves clinical diagnostic sensitivity by 10% to 27%, particularly achieved by different algorithms or scores. OBJECTIVE: We sought to develop a simplified and highly accurate dermoscopic-point list for cutaneous melanocytic lesions. METHOD: We studied consecutive patients with suspicious melanocytic lesions, which were excised and histopathologically examined at our institution. On the basis of the ABCD rule of Stolz, Menzies score, and the modified ABCD rule of Kittler, a simplified ABC-point list was developed. Simple points were given for the following: asymmetry of outer shape (A) or differential structures inside the lesion in at least 1 axis ((A)); the abrupt cutoff of network at the border in at least one quarter of circumference (B); 3 or more colors (C); 3 or more differential structures (D); or noticed change (evolution) in the last 3 months (E). Using 20-fold magnification of computer dermoscopy, the sensitivity, specificity, and diagnostic accuracy were examined in 269 cutaneous melanocytic lesions. Of these, 84 (31.2%) were cutaneous melanomas. Also, the sensitivity, specificity, and diagnostic accuracy were investigated with a 7-point checklist and the 7 features for melanoma. RESULTS: With the ABC-point list for the diagnosis of cutaneous melanoma, sensitivity was 90.5%, specificity was 87%, and diagnostic accuracy was 88.1%, confirmed by cross-validation. The ABCD rule resulted in 90.5%, 72.4%, and 78.1%; Menzies score in 95.2%, 77.8%, and 83.3%; 7-point checklist in 90.5%, 87%, and 88.1%; and 7 features for melanoma in 94%, 74.6%, and 80.7%, respectively, CONCLUSIONS: The ABC-point list is simpler than the already established algorithms. Despite its simplicity, a high sensitivity, specificity, and diagnostic accuracy was achieved. This simplified approach in dermoscopic diagnostics may contribute to further spread and enable to learn and use this method more easily.     

Comparative performance of 4 dermoscopic algorithms by nonexperts for the diagnosis of melanocytic lesions

OBJECTIVE: To assess 4 dermoscopy methods in a nonexpert setting. DESIGN: Sixty-one medical practitioners, mainly primary care physicians in Australia, were trained in 4 dermoscopy algorithms. Participants then assessed macroscopic and dermoscopic images of 40 melanocytic skin lesions. Each of the dermoscopic images was assessed with pattern analysis, the 7-point checklist, the ABCD rule, and the Menzies method. RESULTS: The Menzies method showed the highest sensitivity, 84.6%, for the diagnosis of melanoma, followed by the 7-point checklist (81.4%), the ABCD rule (77.5%), pattern analysis (68.4%), and assessment of a macroscopic image (60.9%). Pattern analysis and assessment of the macroscopic image showed the highest specificity, 85.3% and 85.4%, respectively. The ABCD rule showed a specificity of 80.4%; the Menzies method, 77.7%; and the 7-point checklist, 73%. The Menzies method had a diagnostic accuracy of 81.1%; the ABCD rule, 79.0%; the 7-point checklist, 77.2%; pattern analysis, 76.8%; and clinical assessment, 73.2%. CONCLUSIONS: All algorithms performed well in the hands of relatively inexpert practitioners who had undertaken self-guided training provided on compact disc. The Menzies method showed the highest diagnostic accuracy and sensitivity for melanoma diagnosis and was preferred by study participants.     

Objective follow-up of atypical melanocytic skin lesions: a retrospective study

Various authors have suggested that information from longitudinal observation (follow-up) of dynamic changes in atypical melanocytic pigmented skin lesions (MPSL) could enable identification of early malignant melanoma escaping initial observation due to an absence of specific clinical and dermoscopic features. The aim of our retrospective study was to determine the existence of numerical variables regarding changes in MPSL that could be useful to differentiate early melanomas and atypical nevi. The study was carried out in two Italian dermatology Centres. Digital dermoscopy analyzers (DB-Mips System) were used to evaluate dermoscopic images of 94 equivocal pigmented skin lesions under observation for 6–12 months and then excised because of changes across time (29 melanomas and 65 nevi). The analyzer evaluates 49 parameters grouped into four categories: geometries, colours, textures and islands of colour. The ROC curve designed on the 49 digital dermoscopy analysis parameters showed good accuracy. At sensitivity (SE) = specificity (SP), it correctly classified 89.3% of cases. When objective pigmented skin lesion parameters were considered together with their objective changes over 6–12 months, a decisive increase in discrimination capacity was obtained. At SE = SP accuracy was 96.3%. Analysis of the parameters of our model and statistical analysis enabled us to interpret/identify the most significant factors of modification and differentiation of lesions, providing quantitative insights into the diagnosis of equivocal MPSL and demonstrating the utility of objective/numerical follow-up.     

Clinical selection of melanocytic lesions for dermoscopy decreases the identification of suspicious lesions in comparison with dermoscopy without clinical preselection

BACKGROUND: In most cases dermoscopy is performed only on lesions selected by clinical inspection which present worrying clinical features or appear to deviate from the patient's average type of naevus. Thus, possible early malignant melanomas (MMs) or MM precursors, lacking typical clinical characteristics, may elude the dermoscopic examination. OBJECTIVES: To perform a comparison between two different approaches to the patient's examination, one based on a clinical preselection of lesions to be examined by dermoscopy, and the other consisting of the dermoscopic scrutiny of all melanocytic lesions with a diameter>or=2 mm (total dermoscopy). METHODS: Sixty-three consecutive patients with MM, undergoing periodic dermoscopic examinations of their naevi, were enrolled in the study. The patients first underwent an assessment of the entire skin with the unaided eye for the identification of lesions for dermoscopy. Subsequently, the patients underwent dermoscopic examination of all melanocytic lesions. Images of naevi identified by clinical examination or by total dermoscopy as having dermoscopic aspects characteristic of a suspicious lesion, i.e. necessitating either surgical excision or follow-up examinations, were separately recorded, classified and described employing the ABCD rule of dermoscopy and the seven-point checklist. RESULTS: Five hundred and fifty-one lesions were chosen by clinical inspection for subsequent dermoscopic examination; among these, 117 were considered for excision or follow-up. Ninety-two further lesions were identified for excision or follow-up by employing only total dermoscopy. Dermoscopy scores of lesions selected by clinical inspection plus dermoscopy were similar to those identified by dermoscopy alone. In the former group, 13 lesions showed either an ABCD or a seven-point score corresponding to a suspicious lesion, whereas eight such lesions were identified only by total dermoscopy. Thus, by clinical selection plus dermoscopy we were able to identify only 62% of dermoscopically suspicious lesions. CONCLUSIONS: Clinical selection of melanocytic lesions for dermoscopic examination is associated with the 'loss' of a conspicuous number of lesions which deserve surgical excision or follow-up examinations. Total dermoscopy, enabling the detection of suspicious lesions, together with storage, retrieval and sequential comparison of their images, could enhance MM diagnosis by follow-up, in comparison with clinical preselection for dermoscopy.     

The dermoscopic classification of atypical melanocytic naevi (Clark naevi) is useful to discriminate benign from malignant melanocytic lesions

BACKGROUND: The dermoscopic classification is a useful tool for handling patients with atypical naevi (Clark naevi). OBJECTIVES: To investigate if the dermoscopic classification of atypical naevi is of any value to discriminate benign from malignant melanocytic lesions. METHODS: Consecutive patients (n = 205) were included with 254 suspicious melanocytic lesions, confirmed by histopathology at the Pigmented Lesions Clinic of the Department of Dermatology, University Medical Center, University of Tuebingen, Germany. In this retrospective study, dermoscopic images of benign and malignant melanocytic lesions were classified according to the dermoscopic classification of atypical naevi (reticular, globular, homogeneous or combinations of two of these) and pigmentation (uniform, central hyper- or hypopigmentation, eccentric peripheral hyper- or hypopigmentation, or multifocal hyper- or hypopigmentation). The three-structure type (reticular, globular and homogeneous) was additionally defined. RESULTS: Reticular, homogeneous and reticular-homogeneous types were significantly more frequent in naevi than in melanomas, whereas the three-structure type was significantly more frequent in melanomas (P < 0.001). A sensitivity of 86.7%, specificity of 87.7% and diagnostic accuracy of 87.4% was obtained. Uniformly pigmented and centrally hyperpigmented types were significantly more frequent in naevi than in melanomas, whereas eccentric peripheral hyperpigmented and multifocal hyper- or hypopigmented types were significantly more frequent in melanomas (P < 0.001). CONCLUSIONS: The dermoscopic classification of atypical naevi (Clark naevi) is useful to discriminate benign from malignant melanocytic lesions. The three-structure type and eccentric peripheral hyperpigmentation were significantly more frequently found in malignant than in benign melanocytic lesions. The knowledge of these two dermoscopic types should be helpful for the management of patients presenting with multiple melanocytic lesions.     

Pre-operative diagnosis of pigmented skin lesions: in vivo dermoscopy performs better than dermoscopy on photographic images

BACKGROUND: Epiluminescence microscopy (ELM) (dermoscopy, dermatoscopy) is a technique for non-invasive diagnosis of pigmented skin lesions that improves the diagnostic performance of dermatologists. Little is known about the possible influence of associated clinical features on the reliability of dermoscopic diagnosis during in vivo examination. OBJECTIVE: To compare diagnostic performance of in vivo dermoscopy (combined clinical and dermoscopic examination) with that of dermoscopy performed on photographic slides (pure dermoscopy). DESIGN: This case series comprised 256 pigmented skin lesions consecutively identified as suspicious or equivocal during examination in a general dermatological clinic. Clinical examination and in vivo dermoscopy were performed before excision by two trained dermatologists. The same observers carried out dermoscopy on photographic slides at a later time, and these three diagnostic classifications were reviewed together with the histological findings for the individual lesions. This was carried out in a university hospital. RESULTS: In vivo dermoscopy performed better than dermoscopy on photographic slides for classification of pigmented skin lesions compared with histological diagnosis, and both performed better than general clinical diagnosis. In vivo dermoscopic diagnosis of melanoma showed 98.1% sensitivity, 95.5% specificity and 96.1% diagnostic accuracy while dermoscopic diagnosis of melanoma on photographic slides was less reliable with 81.5% sensitivity, 86.7% specificity and 85.2% diagnostic accuracy. In particular, diagnosis of melanoma based on photographic slides led to nine false negative cases (three in situ, six invasive; thickness ranges 0.2-1.5 mm). CONCLUSIONS: In vivo dermoscopy, i.e. combined clinical and dermoscopic examination, is more reliable than dermoscopy on photographic slides. In clinical practice, therefore, in vivo dermoscopy cannot be considered independent from associated clinical characteristics of the lesions, which help the trained observer to reach a more precise classification. This may have implications on the reliability of ELM diagnosis made by an observer not fully trained in the clinical diagnosis of pigmented skin lesions or by a remote observer during digital ELM teleconsultation.     

反射式共聚焦显微镜联合皮肤镜对黑素细胞痣的诊断价值评估

目的 评估皮肤镜与反射式共聚焦显微镜(RCM)单独或联合对黑素细胞痣的诊断价值.方法 收集临床拟诊黑素细胞痣的患者37例,对皮损先进行皮肤镜、RCM检查,再经组织病理学检查确诊.总结黑素细胞痣的影像学特征,计算不同检查诊断黑素细胞痣的敏感度、特异度、阳性预测值、阴性预测值、正确率,分析皮肤影像技术与组织病理学诊断的一致性.结果 皮肤镜和RCM检查结果示真皮内痣细胞的形态结构可分为两种:(a)真皮乳头层不融合、高折光、圆形的痣细胞,皮肤镜下表现为褐色或浅褐色均质模式,见于5处皮损;(b)真皮乳头内不规则、高折光的痣细胞团块,皮肤镜表现为鹅卵石模式或球状模式,见于31处皮损.在诊断黑素细胞痣方面,RCM结合皮肤镜的敏感度、特异度、正确率、阳性预测值、阴性预测值分别为91.7％、87.5％ 、90.9％ 、97.1％ 、70％,RCM为86.1％ 、75％ 、84％ 、93.9％ 、54.5％,皮肤镜为77.8％ 、87.5％ 、75％ 、96.3％ 、41.2％.除特异度与皮肤镜相同外,RCM结合皮肤镜的其他指标均高于二者单独应用;RCM敏感度、正确率、阴性预测值高于皮肤镜,特异度、阳性预测值低于皮肤镜.RCM结合皮肤镜或单用RCM与组织病理诊断结果之间差异无统计学意义(x2值分别为0.25、0.57,P值分别为0.63、0.45),Kappa值分别为0.72、0.53;皮肤镜与病理诊断结果之间差异有统计学意义(x2=5.81,P=0.012).结论 RCM联合皮肤镜较二者单独使用能更准确地诊断黑素细胞痣.     

Is dermoscopy (epiluminescence microscopy) useful for the diagnosis of melanoma? Results of a meta-analysis using techniques adapted to the evaluation of diagnostic tests

OBJECTIVE: To assess, by means of meta-analysis techniques for diagnostic tests, the accuracy of dermoscopic (also known as dermatoscopy and epiluminescence microscopy) diagnosis of melanoma performed by experienced observers vs. naked-eye clinical examination. DATA SOURCES: MEDLINE, EMBASE, PASCAL-BIOMED, and BIUM databases were screened through May 31, 2000, without any language restrictions. STUDY SELECTION: Original studies were selected when the following criteria were met: spectrum of lesions well described, histologic findings as standard criterion, and calculated or calculable sensitivity and specificity. Eight of 672 retrieved references were retained. DATA EXTRACTION: Three investigators extracted data. In case of disagreement, consensus was obtained. Summary receiver operating characteristic curve analysis was used to describe the central tendency of the studies, and to compare dermoscopy and clinical examination. DATA SYNTHESIS: Selected studies represented 328 melanomas, mostly less than 0.76 mm thick, and 1865 mostly melanocytic benign pigmented skin lesions. For dermoscopic diagnosis of melanoma, the sensitivity and specificity ranges were 0.75 to 0.96 and 0.79 to 0.98, respectively. Dermoscopy had significantly higher discriminating power than clinical examination, with respective estimated odds ratios of 76 (95% confidence interval, 25-223) and 16 (95% confidence interval, 9-31) (P =.008), and respective estimated positive likelihood ratios of 9 (95% confidence interval, 5.6-19.0) and 3.7 (95% confidence interval, 2.8-5.3). The roles of the number of lesions analyzed, the percentage of melanoma lesions, the instrument used, and dermoscopic criteria used in each study could not be proved. CONCLUSION: For experienced users, dermoscopy is more accurate than clinical examination for the diagnosis of melanoma in a pigmented skin lesion.     

Three-point checklist of dermoscopy. A new screening method for early detection of melanoma

BACKGROUND: Dermoscopy used by experts has been demonstrated to improve the diagnostic accuracy for melanoma. However, little is known about the diagnostic validity of dermoscopy when used by nonexperts. OBJECTIVE: To evaluate the diagnostic performance of nonexperts using a new 3-point checklist based on a simplified dermoscopic pattern analysis. METHODS: Clinical and dermoscopic images of 231 clinically equivocal and histopathologically proven pigmented skin lesions were examined by 6 nonexperts and 1 expert in dermoscopy. For each lesion the nonexperts assessed 3 dermoscopic criteria (asymmetry, atypical network and blue-white structures) constituting the 3-point method. In addition, all examiners made an overall diagnosis by using standard pattern analysis of dermoscopy. RESULTS: Asymmetry, atypical network and blue-white structures were shown to be reproducible dermoscopic criteria, with a kappa value ranging from 0.52 to 0.55. When making the overall diagnosis, the expert had 89.6% sensitivity for malignant lesions (tested on 68 melanomas and 9 pigmented basal cell carcinomas), compared to 69.7% sensitivity achieved by the nonexperts. Remarkably, the sensitivity of the nonexperts using the 3-point checklist reached 96.3%. The specificity of the expert using overall diagnosis was 94.2% compared to 82.8 and 32.8% achieved by the nonexperts using overall diagnosis and 3-point checklist, respectively. CONCLUSION: The 3-point checklist is a valid and reproducible dermoscopic algorithm with high sensitivity for the diagnosis of melanoma in the hands of non-experts. Thus it may be applied as a screening procedure for the early detection of melanoma.     

Dermoscopy in black people

BACKGROUND: Little is known about the use of dermoscopy in nonwhite-skinned populations and whether it can influence diagnostic performance. OBJECTIVES: To evaluate for the first time the utility and efficacy of dermoscopy in a black population for the diagnosis of pigmented cutaneous lesions. METHODS: In total, 100 consecutive clinically doubtful or equivocal pigmented skin lesions in black patients were submitted to dermoscopic examination. The lesions were observed using dermoscopy by two groups of dermatologists, one in Brazil (in vivo) and the other in Italy (on slide images). Besides diagnosis, each group recorded on the same type of form the dermoscopic features present. RESULTS: Of 100 clinically suspicious cases, 79 were Clark naevi, 15 seborrhoeic keratoses, four blue naevi, one dermatofibroma and one melanoma. The two groups of observers succeeded in identifying and classifying all the lesions to such a margin of diagnostic accuracy that only a few cases (three Clark naevi) were subjected to surgical excision to confirm diagnosis. CONCLUSIONS: Darker pigmentation of the skin does not impede the identification of single dermoscopic features. As in lighter-skinned populations, dermoscopy in black people can also lead to early and accurate diagnosis of melanoma, thereby significantly reducing the number of unnecessary excisions.