A male patient, 72 years old, had a history of melanoma (AJCC stage IB) located on the left leg. During a regular follow-up visit, we observed an asymmetric, brown, blue-gray plaque with 1.2 cm maximum diameter, sharply delimited on the right supraclavicular region. On dermoscopy, the lesion presented a multicomponent pattern, with 4 colors (brown, gray, blue, and white), a globular atypical pattern, pseudonetwork, and asymmetrical globules. In the left area of the image, it was possible to see a homogenous brown area, with overlapping gray and white shiny structures and ovoid nests which led to the suspicion of a collision tumor of seborrheic keratosis and basal cell carcinoma or melanoma, mainly because of these two distinctive patterns on the same area ( Figure 1 ). The lesion was excised, and the histology was compatible with a seborrheic keratosis.
Figure 1 .
Dermoscopy image of a cutaneous lesion presenting with a multicomponent pattern, with 4 colors, a globular atypical pattern, pseudonetwork, and asymmetrical globules.
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