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Notes: Summary Little is currently known about the relationship between melanocytic naevi and melanoma in terms of neoplastic progression. At histological examination, remnants of a pre-existing melanocytic naevus adjoining a melanoma are seen in 20–30% of cases. This study investigated dermoscopic features of 108 naevus-associated melanomas, identified on the basis of histological classification, consecutively observed at a University Department. Because of the risk of misclassification due to destruction of naevus remnants in thick tumours, only lesions of 〈 1 mm Breslow thickness were considered. We found naevus-associated melanomas showing atypical pigment networks and regression patterns more frequently than de novo melanomas, while irregular blotches and atypical vascular patterns were found less frequently. Dermatologists should be aware that dermoscopic features of melanoma differ according to the histogenesis of the lesion. Atypical pigment networks and regression patterns are the most useful dermoscopic criteria suggested to make a diagnosis of naevus-associated melanoma.

Notes: Summary The clinical appearance of cutaneous endometriosis can share some features with malignant melanoma, thus representing a possible cause for concern in both patient and clinician. In recent years, the use of epiluminescence microscopy (ELM, dermoscopy) has proved useful in improving the accuracy of diagnosis of pigmented skin lesions. The purpose of this study was to analyse the dermoscopic features of cutaneous endometriosis with histopathological correlation. We studied a case which showed homogeneous reddish pigmentation, regularly distributed. Within this typical pigmentation there were small red globular structures, but more defined and of a deeper hue, which we called ‘red atolls’. ELM thus revealed a distinctive pattern in cutaneous endometriosis.

Notes: 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.

Notes: 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.

Notes: The diagnosis of seborrheic keratosis is, in general, a clinical one, but in some cases, the differential diagnosis between pigmented seborrheic keratosis and malignant melanoma is difficult. Dermoscopy may improve the early diagnosis of vulvar melanoma and thus play a role in the preoperative classification of pigmented lesions at this particular site. We report the first case of a pigmented seborrheic keratosis of the vulva clinically mimicking a malignant melanoma, whose dermoscopic features have been investigated together with their pathologic correlates. Dermoscopically our case shows the absence of comedo-like openings and the presence of the pseudo-network. Dermoscopy is therefore a useful method for the differential diagnosis of pigmented lesions even in the vulva.

Notes: Self-detection of suspicious pigmented skin lesion combined with rapid referral to dermatologic centres is the key strategy in the fight against melanoma. The investigation of factors associated with pattern of detection of melanoma (self- vs. nonself-detection) may be useful to refine educational strategies for the future. We investigated the frequency of melanoma self-detection in a Mediterranean population at intermediate melanoma risk. A multicentric survey identified 816 consecutive cases of cutaneous melanoma in the period January to December 2001 in 11 Italian clinical centres belonging to the Italian Multidisciplinary Group on Melanoma. All patients filled a standardized questionnaire and were clinically examined by expert dermatologists. Self-detected melanomas were 40.6%, while the remaining lesions were detected by a dermatologist (18.5%), the family physician (15.2%), other specialists (5%), the spouse (12.5%), a friend or someone else (8.2%). Variables associated with self-detected melanomas were female sex, young age, absence of atypical nevi, knowledge of the ABCD rule, habit of performing skin self-examination. Self-detected melanomas did not differ from nonself-detected tumours in term of lesion thickness; however, patients with self-detected melanomas waited a longer period before having a diagnostic confirmation (patient's delay) (〉 3 months: odds ratio, 3.89; 95% confidence interval, 2.74–5.53). In order to reduce the patients' delays, educational messages should adequately stress the need for a prompt referral to a physician once a suspicious pigmented lesion is self-detected.

Notes: We report a case of three distinct adnexal neoplasms associated with a naevus sebaceous of the scalp: a nodular pigmented trichoblastoma, a smaller flat pigmented trichoblastoma and a syringocystadenoma papilliferum, and discuss the clinical and histological features of these neoplasms. The clinical manifestation was suggestive of malignant melanoma, a feature that has never been reported before. For the first time in the literature we describe the case also by means of a noninvasive analysis, i.e. epiluminescence microscopy. In our experience, epiluminescence microscopy does not appear to be more diagnostically accurate than simple clinical examination when diagnosing lesions of the scalp, contrary to other regions.