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.     

Complex dermoscopic pattern: a potential risk marker for melanoma

BACKGROUND: Dysplastic naevi have repeatedly been shown to be an independent risk factor for melanoma; however, risk estimates vary. Dermoscopy has allowed for more elaborate classification of naevi based on global patterns. OBJECTIVES: To assess dermoscopic images of naevi from patients with melanoma and controls to explore dermoscopic patterns that are associated with melanoma risk. METHODS: Dermoscopic images of naevi from the backs of 20 patients with melanoma and 20 age- and sex-matched controls were reviewed for dermoscopic patterns and structures. An unblinded review of 187 naevi of patients and 150 naevi of controls was completed. Complex global dermoscopic pattern was defined in naevi presenting both network and globules, with or without structureless areas. RESULTS: Complex global dermoscopic pattern was observed more frequently in melanoma patients than controls (odds ratio, OR 2.9, P = 0.003). As for specific dermoscopic structures, presence of globules was observed more frequently in patients than controls (OR 2.3, P = 0.0001), whereas presence of dots was inversely associated with case status (OR 0.5, P = 0.002). CONCLUSIONS: These pilot data suggest that dermoscopic pattern may serve as a more robust and specific marker of melanoma risk than clinical naevus phenotype.     

Reticular grey‐blue areas of regression as a dermoscopic marker of melanoma in situ

Background By dermoscopy, regression structures are substantially defined by the presence of white and blue areas in the lesion image. As fibrosis and melanosis are often seen in malignant melanoma (MM), the presence of dermoscopic signs of regression may represent a clue for the diagnosis of malignancy. Objectives To assess the frequency and extent of dermoscopic signs of regression in melanoma in situ (MIS) and to describe its dermoscopic features. Methods Dermoscopic images of 85 MIS, 85 invasive MMs and 85 dermoscopically equivocal lesions with a histological diagnosis of naevus were evaluated by three dermatologists, who assessed the presence of 11 parameters of regression. Results The number of regression parameters per lesion increased according to melanoma thickness. White areas, the grey‐blue veil and widespread blue areas were more frequent in invasive MMs than in the other two lesion groups, whereas light brown areas and regression of dermoscopic structures were more frequent in MIS. Peppering was observable in the same percentage of MIS and invasive MMs. Blue areas were more frequently structureless in equivocal lesions and invasive MMs, whereas the reticular pattern prevailed in MIS. Conclusions Frequency, morphology, extent and distribution of regression vary according to melanoma thickness and diameter. Lesions with reticular blue regression and light brown areas should undergo surgical excision for the suspicion of MIS. Moreover, the identification of the reticular pattern of blue regression can be considered a significant discriminator and a reliable predictor of MIS.     

Dermoscopic features of acral lentiginous melanoma in a large series of 110 cases in a white population

Summary Background Acral lentiginous melanoma (ALM) is a rare but distinctive subtype of melanoma. The diagnosis is often delayed and misdiagnosis is common, due to frequently unusual clinical presentation and a higher rate of amelanosis than in other melanoma subtypes. Objectives We aimed to investigate the dermoscopic features of a large series of ALM in a white‐skinned population, in order to emphasize their diagnostic value. Methods All recorded dermoscopic photographs of ALM, including nail unit variants, were collected from the files of the University Hospital Department of Dermatology (Lyons, France) and reviewed. Results In total 110 lesions, including 66 (60%) palmoplantar ALM and 44 (40%) ALM of the nail apparatus, were analysed for dermoscopic characteristics. The mean Breslow thickness was 2·6 mm. In volar skin melanomas, the two most prevalent patterns were irregular diffuse pigmentation (60%) and the parallel‐ridge pattern (53%). Minor dermoscopic patterns, commonly noted in benign lesions, were also detected but only focally within the lesions. Among the 44 nail unit lesions, 31 (70%) presented irregular lines with variegations in colours, spacing, width and disruption of parallelism. Two cases of melanonychia striata had a triangular shape. Both corresponded to early ungual ALM. Association with subungual haemorrhage was not uncommon. The study included 37 (34%) amelanotic melanomas. However, dermoscopy enabled detection of microscopic remnants of pigmentation in most cases. The vascular pattern found in almost half of these lesions was polymorphous, with combinations of milky‐red areas (95%), linear irregular vessels (49%), dotted vessels (43%) and hairpin vessels (41%). Conclusions The presence of a parallel‐ridge pattern and/or irregular diffuse pigmentation within the lesion is highly indicative of melanoma on volar skin. An irregular lines pattern is the most prominent dermoscopic feature of pigmented ALM of the nail apparatus. Amelanotic ALM either in volar skin or in nail apparatus is characterized by remnants of pigmentation and a polymorphic vascular pattern.     

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.     

Epidermolysis bullosa naevi reveal a distinctive dermoscopic pattern

BACKGROUND: Large, asymmetrical and irregularly pigmented naevi in patients with epidermolysis bullosa (EB) have been reported often to mimic cutaneous melanoma clinically. OBJECTIVES: As the biological course of these peculiar moles is benign, we assessed EB naevi with a dermatoscope to determine whether they could be reliably differentiated from cutaneous melanoma. METHODS: We evaluated digital dermoscopic images of 23 EB naevi from 11 patients with EB and analysed these pigmented lesions according to pattern analysis, ABCD rule of dermoscopy and the seven-point checklist. RESULTS: Melanoma-associated dermoscopic criteria such as multicomponent pattern (20 of 23), atypical pigment network (17 of 23), irregular dots/globules (16 of 23), irregular pigmentation (22 of 23) and an atypical vascular pattern (seven of 23) were frequently seen in EB naevi. In contrast, other criteria frequently associated with melanoma progression, such as irregular streaks, blue-whitish veil, regression structures (blue-whitish areas) or black dots, were rarely seen. Most lesions gave false-positive results when the scores of the dermoscopic diagnostic algorithms were calculated. CONCLUSIONS: Recurring dermoscopic structures in EB naevi reveal a distinctive dermoscopic pattern of this recently defined entity. Although EB naevi represent an exception to dermoscopic diagnostic algorithms, their dermoscopic evaluation most often allows us to estimate their benign nature. Nevertheless, as an unequivocal discrimination from malignant melanoma in vivo is sometimes not possible, regular clinical follow up of EB naevi with histopathological evaluation of highly suspicious lesions is mandatory.     

Telediagnosis and face-to-face diagnosis reliability for melanocytic and non-melanocytic 'pink' lesions

Background Telemedicine is a worldwide healthcare practice that, during the last years, has dramatically reduced the time of consultation for patients. Teledermoscopy aids in the current management of skin cancers in general and particularly of melanoma; telemedicine and teledermoscopy give the chance to provide consultations with experts also by long distance. Objective The purpose of this study is to determine the diagnostic reliability, according to interobserver agreement, between clinical and dermoscopic diagnosis of lesions with poor and/or absent pigmentation, comparing face‐to‐face diagnosis and telediagnosis. Materials and methods Forty‐four lesions were examined by two different dermatologists with good and similar experience in the clinical field and dermoscopy. A store‐and‐forward teledermatological system, based on clinical and dermoscopic images, was done by the two skilled dermatologists. Results Our results underline that teledermoscopy of ‘pink’ lesions does not provide a similar degree of diagnostic accuracy as otherwise in face‐to‐face diagnosis perhaps due to the absence of typical criteria. Atypical skin lesions are characterized by the absence of typical dermoscopic patterns, and their teleconsultation does not always increase the diagnostic accuracy.     

Dermoscopic features of cutaneous local recurrent melanoma

We describe for the first time the dermoscopic features of cutaneous recurrent melanoma including a globular pattern and a diffuse nonhomogeneous pigmentation. These findings greatly differ from those observed in primary cutaneous melanoma and should be considered in the dermoscopic differential diagnosis of pigmented skin lesions.     

Ex vivo dermoscopy of cutaneous biopsies for melanocytic neoplasms: a retrospective review of 517 cases with histopathologic correlation

ABSTRACT:: Clinical dermoscopy has provided new insights into the diagnosis and classification of melanocytic neoplasms. There are only limited data on its applications in dermatopathology. In our laboratory, we routinely photograph all skin biopsies with ex vivo dermoscopy (EVD). We retrospectively reviewed 517 cutaneous biopsies with corresponding EVD images to determine whether EVD provides useful ancillary information in the histopathologic diagnosis of melanocytic neoplasms. Four hundred eighty-three cases (93.4%) yielded usable images. The lesions could be categorized according to a published dermoscopic classification system of melanocytic proliferations. Reticular pigmentation correlated with dysplastic nevi, globular pigmentation with congenital nevi, homogenous blue pigmentation with blue nevi, starburst peripheral globular pigmentation with Spitz nevi, and atypical pigment patterns with melanoma. Eighteen of 25 cases (72%) with ambiguous histopathology were assigned a more definite diagnosis when reviewed contemporaneously with EVD images. The surgical margins in 40 cases (7.7%) were reclassified when EVD images were included in the review. We found EVD to be a useful technique and advocate its use for diagnosis and clinical-pathologic correlation.     

Dermoscopy of fully regressive cutaneous melanoma

Background Metastatic melanoma of unknown origin is a difficult challenge diagnostically and therapeutically. Diagnosis of the putative primary lesion is difficult. This difficulty increases when the primary lesion has undergone complete regression. Objective To define the dermocopic features of fully regressed melanoma. Patients and methods A single‐institution, register‐based study of an unselected consecutive series of seven cases of metastatic melanoma in the lymph nodes with no known or visible primary lesion was carried out. Skin examination included dermoscopy; when a suspicious area was found, observed dermoscopic features were recorded and a biopsy was performed. Diagnosis of completely regressive cutaneous melanoma was based on clinical–pathological correlation according to widely accepted criteria. Results Seven dermoscopic features were associated with completely regressive melanoma: scar‐like depigmentation (100%); pink coloration of the background (100%); linear‐irregular vessels (86%); globular pattern of the vessels (43%); remnants of pigmentation (86%), either macular (43%) or with a peppering aspect (43%); and white lighter transverse bands (43%). The last feature was only observed with polarized light dermoscopy devices. Conclusion Dermoscopy more accurately distinguishes the vascular, pigmentary and scarring changes of fully regressive melanoma. We believe that dermoscopy should be included in the search for a regressive primary lesion in case of metastatic melanoma of unknown origin.     

Slow‐growing melanoma: a dermoscopy follow‐up study

Background Recent evidence suggests that melanoma is a family of different tumours with varying abilities to grow and metastasize. Trends in melanoma epidemiology show a strong increase in the incidence of thin melanoma, with no corresponding increase in mortality or incidence of thick melanoma. We initially evaluated five cases and found that none had baseline features suggestive of melanoma; excision was performed based on slight changes visible only in side‐by‐side comparisons of dermoscopic images. Objectives To assess the clinico‐dermoscopic features and the growth patterns of melanomas that were excised after a follow‐up of 1 year or more due to their inconspicuous features at the baseline consultation. Methods In a multicentre, retrospective study of histopathologically confirmed melanomas excised after follow‐up, we analysed dermoscopic images obtained at the initial consultation and compared them with images obtained at the last follow‐up consultation. Images were analysed and graded using standard algorithms and scored for changes in size, symmetrical or asymmetrical structural change, and development of new melanoma‐specific criteria. An overall score reflecting the amount of change was calculated for each lesion. Results Our series consisted of 103 melanomas. After a median follow‐up of 20 months, most lesions were still in situ or early invasive (median Breslow thickness of 0·48 mm), with only three lesions showing tumour thickness of 1 mm or more. The most frequent baseline characteristics were asymmetrical pigmentation (78·6% of lesions), reticular overall pattern (62·1%), and regression features (35·9%). Most melanomas (58·3%) showed minor to moderate changes over time, with < 2 mm size increase, with asymmetrical structural change, and without development of new melanoma‐specific criteria. Major changes were visible only after a mean follow‐up of 33 months. Conclusions This study provides evidence for the existence of a subgroup of slow‐growing melanomas, which may explain the increase in the incidence of thin melanoma, despite stable rates of thick melanoma and melanoma‐associated mortality.     

Dermoscopy of desmoplastic melanoma: report of six cases

Background  Desmoplastic melanoma (DM) is a rare variant of cutaneous melanoma. Its diagnosis is often delayed by an unusual clinical presentation. The dermoscopic features of DM have not yet been described.
Objective  To define the dermoscopic features of DM.
Patients and methods  A single-institution register-based retrospective study of six cases of histology-proven desmoplastic melanoma for which dermoscopy data were available. The criteria we studied included: network, dots and globules, streaks, regression features, ulceration, number of colours, blue/white veil, and vascular pattern.
Results  Only three cases exhibited one classical feature for a melanocytic lesion; other cases were recognized on the basis of the presence of figures of regression (all six), i.e. white scar-like areas and 'peppering' (three of six), multiple (> 4) colours (five of six), and of melanoma-related vascular patterns (five) such as linear-irregular vessels (four) and milky-red areas (two).
Discussion  We believe that dermoscopy could help in the accurate diagnosis of this rare neoplasm. In the absence of a pigmented network, attention should be given to the identification of features of regression and to melanoma-associated vascular patterns.     

Can early malignant melanoma be differentiated from atypical melanocytic nevus by in vivo techniques?

Background/aims: Differentiation between early (Breslow thickness less than 1 mm) malignant melanoma (MM) and atypical melanocytic nevus (AMN) remains a challenge even to trained clinicians. The purpose of this study is to determine the feasibility of reliable discrimination between early MM and AMN with noninvasive, objective, automatic machine vision techniques.
Methods: A data base of 104 digitized dermoscopic color transparencies of melanocytic lesions was used to develop and test our computer-based algorithms for classification of such lesions as malignant (MM) or benign (AMN). Histopathologic diagnoses (30 MM and 74 AMN) were used as the "gold standard" for training and testing the algorithms.
Results: A fully automatic, objective technique for differentiating between early MM and AMN from their dermoscopic digital images was developed. The multiparameter linear classifier was trained to provide 100% sensitivity for MM. In the blind test, this technique did not miss a single MM and its specificity was comparable to that of skilled dermatologists.
Conclusions: Reliable differentiation between early MM and AMN with high sensitivity is possible using machine vision techniques to analyze digitized dermoscopic lesion images.     

Three years dermoscopic follow‐up of atypical nevi

Atypical nevi are dynamic lesions and may progressively transform into more or less atypical lesions. We aimed to investigate the dermoscopic features of atypical nevi and dynamic changes in these lesions over a period of 3‐years. Patients with 3‐year dermoscopic follow‐up records were enrolled in the study. We compared the dermatoscopic features of the nevus recorded in the first dermoscopic examination and at the end of the third year. Changes in size (mm), pattern, and color were investigated. The most common dermoscopic patterns were reticular (18 patients; 34%), reticular‐homogeneous (17 patients; 32.1%), and reticular‐globular (7 patients; 13.2%). The most common pigmentation patterns were central hyperpigmentation (28 patients; 52.8%), regular pigmentation (nine patients; 17.0%), and multifocal hypo/hyperpigmentation (eight patients; 15.1%). Twenty‐one (39.6%) patients showed changes in pattern. The transformation from reticular‐homogeneous pattern to the homogeneous pattern was the most frequent change in pattern (7 of 21 patients; 33.3%). The transformation from reticular pattern to reticular‐homogeneous pattern was the second most common change in pattern (5 of 21 patients; 23.8%). Fourteen (26.4%) patients experienced symmetrical enlargement. Symmetrical enlargement was statistically more frequent in patients who showed dermoscopic changes in pattern than in those who did not show any changes in the pattern (p: .038). In this study, we did not observe any new dermoscopic clues for the diagnosis of melanoma during the follow‐up. The nevi tended to turn into a homogeneous (structureless) pattern. We observed that the most common dermoscopic change in pattern was the transformation from reticular‐homogeneous pattern to homogeneous pattern, and the lesions had symmetrical enlargement during this transformation. In conclusion, despite the known association between atypical nevi and the risk of developing melanoma, most atypical nevi do not transform into melanoma. Therefore, our study suggests that the excision of atypical nevi is not necessary and dermatoscopic follow‐up can reduce the number of unnecessary excisions.     

Key point in dermoscopic differentiation between early nail apparatus melanoma and benign longitudinal melanonychia

Longitudinal melanonychia presents in various conditions including neoplastic and reactive disorders. It is much more frequently seen in non-Caucasians than Caucasians. While most cases of nail apparatus melanoma start as longitudinal melanonychia, melanocytic nevi of the nail apparatus also typically accompany longitudinal melanonychia. Identifying the suspicious longitudinal melanonychia is therefore an important task for dermatologists. Dermoscopy provides useful information for making this decision. The most suspicious dermoscopic feature of early nail apparatus melanoma is irregular lines on a brown background. Evaluation of the irregularity may be rather subjective, but through experience, dermatologists can improve their diagnostic skills of longitudinal melanonychia, including benign conditions showing regular lines. Other important dermoscopic features of early nail apparatus melanoma are micro-Hutchinson's sign, a wide pigmented band, and triangular pigmentation on the nail plate. Although there is as yet no solid evidence concerning the frequency of dermoscopic follow up, we recommend checking the suspicious longitudinal melanonychia every 6 months. Moreover, patients with longitudinal melanonychia should be asked to return to the clinic quickly if the lesion shows obvious changes. Diagnosis of amelanotic or hypomelanotic melanoma affecting the nail apparatus is also challenging, but melanoma should be highly suspected if remnants of melanin granules are detected dermoscopically.     

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.     

A new deep learning approach integrated with clinical data for the dermoscopic differentiation of early melanomas from atypical nevi

BackgroundTimely recognition of malignant melanoma (MM) is challenging for dermatologists worldwide and represents the main determinant for mortality. Dermoscopic examination is influenced by dermatologists’ experience and fails to achieve adequate accuracy and reproducibility in discriminating atypical nevi (AN) from early melanomas (EM).ObjectiveWe aimed to develop a Deep Convolutional Neural Network (DCNN) model able to support dermatologists in the classification and management of atypical melanocytic skin lesions (aMSL).MethodsA training set (630 images), a validation set (135) and a testing set (214) were derived from the idScore dataset of 979 challenging aMSL cases in which the dermoscopic image is integrated with clinical data (age, sex, body site and diameter) and associated with histological data. A DCNN_aMSL architecture was designed and then trained on both dermoscopic images of aMSL and the clinical/anamnestic data, resulting in the integrated “iDCNN_aMSL” model. Responses of 111 dermatologists with different experience levels on both aMSL classification (intuitive diagnosis) and management decisions (no/long follow-up; short follow-up; excision/preventive excision) were compared with the DCNNs models.ResultsIn the lesion classification study, the iDCNN_aMSL achieved the best accuracy, reaching an AUC = 90.3 %, SE = 86.5 % and SP = 73.6 %, compared to DCNN_aMSL (SE = 89.2 %, SP = 65.7 %) and intuitive diagnosis of dermatologists (SE = 77.0 %; SP = 61.4 %).ConclusionsThe iDCNN_aMSL proved to be the best support tool for management decisions reducing the ratio of inappropriate excision. The proposed iDCNN_aMSL model can represent a valid support for dermatologists in discriminating AN from EM with high accuracy and for medical decision making by reducing their rates of inappropriate excisions.     

Dermoscopy

First, a brief introduction about types of dermoscope and an explanation on the theory of dermoscopy are provided. Second, some introduction on the difference of dermoscopic pictures between benign and malignant neoplasm is given. Basically, benign lesions tend to show symmetrical dermoscopic structures and colors, whereas malignant lesions have a tendency to present irregular and atypical dermoscopic structures. Third, the relationship between dermoscopic images and anatomical structures will be shown. Acral melanocytic lesions have site-specific dermoscopic patterns, namely parallel furrow pattern or parallel ridge pattern. These parallel patterns are due to different distribution of benign and malignant melanocytes. Benign melanocytes (nevus cells) are mainly found on the tips of crista profunda limitans and supply melanin granules to the furrows of stratum corneum, making a parallel furrow pattern. To the contrary, melanoma cells proliferate mainly on the tips of crista profunda intermedia or rather diffusely and randomly, and supply melanin granules irregularly and diffusely to the ridges of stratum corneum, having parallel ridge pattern. Fourth, the global features of dermoscopic findings are described respectively with definitions of the technical terms. To analyze dermoscopic structures, it is easier to look at global features first and local features next. Basic global features include reticular, globular, cobblestone, homogeneous, starburst and parallel patterns. If a given dermoscopy image has two patterns, the more prominent pattern might be chosen. If it has more than three dermoscopic patterns, then multi-component pattern is the reasonable selection. If there are no particular dermoscopic structures, then the unspecific pattern will be selected. Finally, some comments on the relationship between dermoscopy and dermatopathology are given briefly. It is always useful to imagine dermatopathological features when examining a dermoscopic image. There are considerable relations between dermoscopy and dermatopathology.