Recurrent Melanocytic Nevi and Melanomas in Dermoscopy

Abstract

IMPORTANCE Differentiating recurrent nevi from recurrent melanoma is challenging. OBJECTIVE To determine dermoscopic features to differentiate recurrent nevi from melanomas. DESIGN, SETTING, AND PARTICIPANTS Retrospective observational study of 15 pigmented lesion clinics from 12 countries; 98 recurrent nevi (61.3%) and 62 recurrent melanomas (38.8%) were collected from January to December 2011. MAIN OUTCOMES AND MEASURES Scoring the dermoscopic features, patterns, and colors in correlation with the histopathologic findings. RESULTS In univariate analysis, radial lines, symmetry, and centrifugal growth pattern were significantly more common dermoscopically in recurrent nevi; in contrast, circles, especially if on the head and neck area, eccentric hyperpigmentation at the periphery, a chaotic and noncontinuous growth pattern, and pigmentation beyond the scar's edge were significantly more common in recurrent melanomas. Patients with recurrent melanomas were significantly older than patients with recurrent nevi (mean [SD] age, 63.1 [17.5] years vs 30.2 [12.4] years) (P<.001), and there was a significantly longer time interval between the first procedure and the second treatment (median time interval, 25 vs 8 months) (P<.001). In a multivariate analysis, pigmentation beyond the scar's edge (P=.002), age (P<.001), and anatomic site (P=.002) were significantly and independently associated with the diagnosis of recurrent melanoma in dermoscopy. CONCLUSIONS AND RELEVANCE Dermoscopically, pigmentation beyond the scar's edge is the strongest clue for melanoma. Dermoscopy is helpful in evaluating recurrent lesions, but final interpretation requires taking into account the patient age, anatomic site, time to recurrence, growth pattern, and, if available, the histopathologic findings of the first excision.

Recurrent halo nevus: Dermoscopy and confocal microscopy features

“…In melanoma, the pigmentation intersects the scar limits, but in RN, pigmentation is limited to the scar 8, 10. In our case, the lesion was confined to the scar but worrisome dermoscopic features and doubtful RCM findings lead us to investigate histopathology further.…”

The recurrent nevus phenomenon

“…On average, recurrence occurs six months after excision, and there is no consensus as to which type of nevus reccurs more often. 1 , 3 - 6 …”

“…On dermoscopy, the presence of pigmentation beyond the border of the scar is the strongest indication for melanoma. 2 , 6 In addition, age over 30 years, location on the face and neck, chaotic pattern of growth, non-continuous growth in dermoscopy, and longer time interval between excision and recurrence are other factors associated with malignancy. Dermoscopy - together with information such as the patient's age, anatomical location, recurrence time, growth pattern, and histological findings of the first excision - guides the final diagnostic interpretation.…”

“…On the other hand, in cases with previous histological examination revealing melanocytic nevus, complete excision is indicated only for aesthetic reasons, and regular dermatoscopic follow-up is a possible and acceptable procedure. 6 …”

The use of combined method in skin tumors treatment

“…Базально-клітинний РШ після хірургічного втручання рецидивує в 4-16,6 % [8] і залежить від гістологічного типу, локалізації пухлини, хірургічної техніки. За результатами дослідження, видалення невеликих невусів методом шейвінгової біопсії дає непогані результати [9]. Рецидиви МН після шейв-біопсії за літературними даними складають 28 % [10].…”