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Notes: Background  Amelanotic malignant melanoma is a subtype of cutaneous melanoma with little or no pigment on visual inspection. It may mimic benign and malignant variants of both melanocytic and nonmelanocytic lesions.Objectives  To evaluate whether dermoscopy is also a useful technique for the diagnosis of amelanotic/hypomelanotic melanoma (AHM).Methods   We conducted a retrospective clinical study of 151 amelanotic/hypomelanotic skin lesions from 151 patients with a mean age of 47 years (± 17·5 SD). Digitized images of amelanotic/hypomelanotic skin lesions were converted to JPEG format and sent by e-mail from the five participating centres. Lesions included 55 amelanotic/hypomelanotic nonmelanocytic lesions (AHNML), 52 amelanotic/hypomelanotic benign melanocytic lesions (AHBML), and 44 AHM, 10 (23%) of which were nonpigmented, truly amelanotic melanomas (AM). The 44 AHM lesions were divided into thin melanomas (TnM) ≤ 1 mm (29 cases) and thick melanomas (TkM) 〉 1 mm (15 cases), according to the Breslow index. Five clinical features (elevation, ulceration, shape, borders and colour) as well as 10 dermoscopic criteria (pigment network, pigmentation, streaks, dots/globules, blue-whitish veil, regression structures, hypopigmentation, leaf-like areas, multiple grey-bluish globules, central white patch) and eight vascular patterns (comma, arborizing, hairpin, dotted, linear irregular, dotted and linear irregular vessels, and milky-red areas) were evaluated in order to achieve clinical and dermoscopic diagnoses. Statistical analyses were performed with the χ2-test and Fisher's exact test, when appropriate.Results  The most frequent and significant clinical features for TnM and TkM were asymmetry and ulceration (the latter only for TkM) compared with AHBML. Irregular dots/globules (62% vs. 35%; P ≤ 0·03), regression structures (48% vs. 27%; P ≤ 0·03), irregular pigmentation (41% vs. 11%; P ≤ 0·03) and blue-whitish veil (10% vs. 0%; P ≤ 0·03) were the most relevant dermoscopic criteria for TnM in comparison with AHBML. TkM differed significantly from AHBML in frequency of occurrence of irregular pigmentation (87% vs. 11%; P ≤ 0·03), irregular dots/globules (73% vs. 35%; P ≤ 0·03), regression structures (67% vs. 27%; P ≤ 0·03), blue-whitish veil (27% vs. 0%; P ≤ 0·03) and hypopigmentation (13% vs. 55%; P ≤ 0·03). Linear irregular vessels and the combination of dotted and linear irregular vessels associated with TnM and TkM were not found in our cases of AHBML and were only rarely seen in AHNML (3·6% and 1·8%, respectively). Moreover, TkM differed significantly from AHBML and TnM in frequency of occurrence of milky-red areas (93% vs. 17%; P ≤ 0·03 and 93% vs. 31%; P ≤ 0·01, respectively). The dermoscopic diagnosis of melanoma had a higher sensitivity and specificity than the clinical diagnosis (89% and 96% vs. 65% and 88%, respectively). With the limitation of the small number of cases, vascular patterns were the only dermoscopic criteria for ‘truly’ AM. In the 10 cases of ‘truly’ AM, we found milky-red areas in more than half of the cases (six of 10), dotted vessels in four, hairpin vessels in two, linear irregular vessels in two, dotted and linear irregular vessels in two.Conclusions  Because dermoscopy uses criteria reflecting pigmentation (irregular pigmentation and irregular dots/globules) and vascular patterns, it is a useful technique not only for pigmented melanoma but also for hypomelanotic melanoma. In ‘truly’ AM, vascular patterns alone may not be sufficient to diagnose melanoma. A combined approach with the clinical information should help in the detection of ‘truly’ AM.

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: Up until now, only lesions selected on the basis of their clinical atypia or which appear equivocal on naked eye examination have been shown to benefit from the use of dermoscopy. In our experience, dermoscopic evaluation of lesions located on the face may require a different approach, as a histopathological diagnosis of malignancy is not uncommon in clinically trivial lesions (i.e. lesions lacking the ABCD criteria for clinical suspicion). Moreover, at this site dermoscopy reveals specific criteria according to the particular histological architecture shown by sun-damaged skin. We report four cases of lentigo maligna (LM) of the face whose identification depended on dermoscopic examination which was performed routinely on all facial lesions, as the lesions did not show ABCD clinical criteria for malignancy. In our experience, the identification of early signs of malignancy by dermoscopy may indicate the excision of LM at an early phase, before the lesion is associated with the ABCD signs of melanoma. Dermatologists should avoid the mistake of immediately excluding a diagnosis of malignancy when examining an ABCD-negative pigmented skin lesion of the face.