Clinicopathologic and Dermoscopic Features of 20 Cases of Spark's Nevus, a Dermoscopic Simulator of Melanoma.

ABSTRACT: Spark's nevus is a particular type of melanocytic nevus, with histology that shows features of both Spitz and Clark nevus. Detailed dermoscopic features in a series of Spark nevi have not been described yet. We performed a monocentric retrospective observational study on 20 lesions of Spark nevus excised from 19 patients (M:F = 10:9; mean age: 37,6 years), reviewed by 5 experts in dermoscopy and 2 dermatopathologists. A histologic review confirmed that Spark nevi were mostly symmetric (80%), well circumscribed (100%), mainly compound (65%) melanocytic lesions with either epithelioid (55%) or spitzoid (45%) cell morphology and bridging of the nests (100%). Spark nevi were more frequently found on the trunk (85%) in patients with a history of sunburns in childhood (84%), with skin phototype III (79%), and with high nevus count (>100 nevi, 7 patients (36%)). On dermoscopy, we observed different general patterns: multicomponent (40%), reticular-globular-homogeneous (15%), globular homogeneous (15%), reticular (15%), reticular-globular (5%), homogeneous (5%), and globular (5%). Spark nevi showed frequently dermoscopic asymmetry (63%), brown color (90%) with areas of central hyperpigmentation (41%) and peripheral hypopigmentation (28%), atypical pigment network (48%), irregular globules (42%), irregular dots (31%), irregular blotches (16%), blue-whitish veil (13%), peripheral island (25%), irregular hyperpigmented areas (12%), and regression (33%). BRAF mutation was present in 7 of the 10 analyzed cases (70%); all these cases presented a history of evolution. In conclusion, Spark nevi occur on the trunk of young adults with high nevus count and history of sunburns; dermoscopic features are protean, often atypical and suspicious of melanoma.

Super-High Magnification Dermoscopy in 190 Clinically Atypical Pigmented Lesions.

Super-high (×400) magnification dermoscopy (D400) is a new non-invasive imaging technique that has been shown to add information for the differential diagnosis of melanocytic lesions in a pilot study. Our study aimed to confirm if D400 can add details for the discrimination of clinically atypical nevus and melanoma. This is a retrospective observational, multicentric study enrolling patients who received ×20 (D20) and ×400 (D400) magnification dermoscopic examinations of pigmented skin lesions. Dermoscopic images were retrospectively evaluated by three observers for the presence/absence of nine D20 and twenty D400 dermoscopic features defined in the previous pilot study. Univariate and multivariate analyses were carried out to find predictors of benign and malignant behaviors. At D20, an atypical pigment network, blue-whitish veil, atypical vascular pattern, regression, and homogenous pattern were more frequent in melanoma than in nevi (p < 0.001). At D400, melanoma showed more frequently than benign lesions, melanocytes with an irregular arrangement and irregular in shape and size (p < 0.001). A network with edged papillae was more frequent in benign lesions than melanomas (p < 0.001). Our study confirms that D400 can identify melanocytes with an irregular arrangement, and irregularities in shape and size in melanomas, adding information to the conventional D20 examination.

Dermoscopy of a Spark's nevus.

Spark's nevus is a particular type of melanocytic nevus that on histology shows features of both Spitz's and Clark's nevus. Clinically, it is an asymmetric, irregular, multicolored, pigmented lesion that is not clearly distinguishable from melanoma or dysplastic (Clark's) nevus. Dermoscopic features have not been described yet, and one could speculate that they are similar to those of Clark's nevi because the histopathologic architecture of Spark's nevus is similar to that of a Clark's nevus, resembling Spitz's nevi in the epithelioid morphology of melanocytes. We present a 32-year-old woman with a Spark's nevus, who upon dermoscopy showed a pronounced atypical network with accentuation of the blue veil and mostly peripheral dots.

Baseline factors influencing decisions on digital follow-up of melanocytic lesions in daily practice: an Italian multicenter survey.

BACKGROUND: Guidelines for optimized use of digital follow-up of melanocytic lesions are not yet available, and little is known about inclusion criteria adopted in clinical practice. OBJECTIVE: Our purpose was to describe the frequency of digital follow-up adoption in melanoma screening, the characteristics of patients and lesions selected, and the predictors of duration of the intervals of digital follow-up. METHODS: Baseline characteristics of patients and lesions selected for digital follow-up in 12 Italian pigmented lesion clinics were examined. Predictors of a short follow-up interval (4.75) was associated only with a marginal effect on the scheduled duration of follow-up interval (OR 1.34, 95% CI 0.97-1.86). These findings were confirmed by a multivariate analysis. LIMITATIONS: The adoption of different digital dermoscopy systems in the participating centers may have limited the reliability of the TDS assigned by a central group to dermoscopy images. CONCLUSIONS: Practicing dermatologists who use digital epiluminescence microscopy in screening for melanoma decided to submit at least one melanocytic lesion to digital follow-up for approximately 1 patient for every 5 examined. This implies costs and time spent that need to be evaluated together with the benefits of this procedure from a large-scale perspective. The lack of well-defined guidelines for inclusion and exclusion criteria may hamper optimized use of digital follow-up in daily practice.