Silva JH et al. and/or family history of melanoma, giving one point to the personal history of melanoma and two points for family history of melanoma (Figure 3). The sum of the points gives rise to the following groups and their respective relative risks (RR) of developing melanoma: group 0: no points (RR: 2-92); group I: 1 point (RR: 8-127); group II: 2 points (RR: 33- 444); group III: 3 points (RR: 85-1269) (Figure 3).3,15,30 Thus, the presence of dysplastic nevi and AMS can be considered as a spectrum of phenotypic expressions, which confers to the carriers different risks of developing melanoma.3,21 The risk spectrum varies from individuals with sporadic dysplastic nevi, with no personal or family history of melanoma, to the opposite extreme with AMS individuals belonging to families in which two or more members had melanoma, forming the so-called familial atypical multiple-mole melanoma syndrome (FAMMM).3,4,15,16,20,31 Besides presenting an increased risk of developing cutaneous melanoma, AMS patients tend to present neoplasia in unusual sites (such as the scalp) at an earlier age than the non-carriers of the syndrome.1 There is also increased risk for multiple melanomas and non-cutaneous melanoma in those patients, such as ocular melanoma.8 Prospective studies show that the risk of melanoma in members of families affected by AMS and FAMMM is significant, with an estimated cumulative risk of 49% in individuals 10 to 50 years of age and 82% in individuals 72 years of age.32 Histopathology Although the histopathologic exam is considered to be the gold standard for the diagnosis of melanocytic tumors, there are limitations in the histologic distinction between early melanomas and dysplastic nevi.12 In several studies, the reproducibility in grading the atypia remains poor to moderate, due to a lack of uniform criteria among dermatopathologists.12,18 Based on the World Health Organization (WHO) and NIH consensus, the histopathologic diagnosis of dysplastic nevi (Figure 4) is based on the major criteria (mandatory) Figure 4 - Histopathologic exam of atypical nevus showing focal atypia of melanocytes, fusion of epithelial cones and concentric lamellar fibrosis. Optical microscopy image with high magnifica- tion (40X). 496 CLINICS 2011;66(3):493-499 and minor criteria (at least two must be present)23, detailed in Table 2. Diagnosis and Follow-Up The clinical distinction between benign and malignant pigmented lesions can be challenging in some cases. However, as demonstrated by several studies, the use of dermoscopy, an auxiliary noninvasive diagnostic method in the clinical dermatological examination, it is possible to increase the diagnostic accuracy of pigmented lesions, including melanomas.33 In a meta-analysis of 27 studies, Kittler et al.34 demonstrated a 49% improvement in diagnostic accuracy, with 6% and 19% increases in specificity and sensitivity, respectively. Moreover, in a randomized study to evaluate the procedure adopted for pigmented lesions using the dermatoscope, Carli et al.35 demonstrated a reduction in the number of patients referred for biopsy (9.0% versus 15.6%). In recent decades, several diagnostic algorithms have been described in dermoscopy for the recognition of melanoma including the Pattern Analysis Method, the ABCD rule, the 7-Point Checklist, the CASH algorithm, the Menzies method and others.33 In a comparison of three algorithms (Pattern Analysis, ABCD Rule and the 7-Point Checklist), Annensi et al.36 demon- strated that the Pattern Analysis method provided the highest sensitivity, specificity and accuracy for the diagnosis of thin melanomas. Although they do not solve all the diagnostic difficulties surrounding the atypical nevus, dermoscopic evaluation and especially monitoring greatly improve the management of these lesions of uncertain behavior.12 Both benign and indeterminate patterns can be identified in dysplastic nevi, using dermoscopy37 (Figure 5). The features most commonly found in dysplastic nevi, described by the Pattern Analysis are the following: atypical pigment network, areas of irregular and peripheral depigmentation, pigmentation with central heterogeneity and abrupt termi- nation and brown globules of different shapes and sizes with irregular distribution.38,39 In dysplastic nevi, black dots in the periphery, pseudopods, branched streaks and blue- whitish veil are rarely found. These structures are more frequently found in cutaneous melanoma.38,39 The pigmented skin lesions with very atypical or nonspecific dermoscopic patterns should be excised for definitive diagnosis by pathology.40,41 Moreover, in patients with multiple nevi, including those with dysplastic nevi and AMS, who tend to have a large number of evolving lesions, dermoscopy alone is not always sufficient to distinguish between benign lesions or new individually suspicious ones.8,42 Thus, the monitoring of nevi in at-risk patients by total body mapping and digital dermoscopy is crucial for both early identification of Table 2 - Dyspalstic Nevus – Histopathological Criteria (NIH). Major Criteria (mandatory) Lentiginous or contiguous melanocytic hyperplasia Focal melanocytic atypia Minor Criteria (at least 2) ‘Shoulder phenomenon’ Fusion of epithelial cones Subepidermal concentric lamellar fibrosis Superficial perivascular lymphocytic inflammatory infiltrate