Dermatoscopic patterns of cutaneous metastases: A multicentre cross-sectional study of the International Dermoscopy Society

Abstract

Background: The detection of cutaneous metastases (CMs) from various primary tumours represents a diagnostic challenge.

Objectives: Our aim was to evaluate the general characteristics and dermatoscopic features of CMs from different primary tumours.

Methods: Retrospective, multicentre, descriptive, cross-sectional study of biopsy-proven CMs.

Results: We included 583 patients (247 females, median age: 64 years, 25%-75% percentiles: 54-74 years) with 632 CMs, of which 52.2% (n = 330) were local, and 26.7% (n = 169) were distant. The most common primary tumours were melanomas (n = 474) and breast cancer (n = 59). Most non-melanoma CMs were non-pigmented (n = 151, 95.6%). Of 169 distant metastases, 54 (32.0%) appeared on the head and neck region. On dermatoscopy, pigmented melanoma metastases were frequently structureless blue (63.6%, n = 201), while amelanotic metastases were typified by linear serpentine vessels and a white structureless pattern. No significant difference was found between amelanotic melanoma metastases and CMs of other primary tumours.

Conclusions: The head and neck area is a common site for distant CMs. Our study confirms that most pigmented melanoma metastasis are structureless blue on dermatoscopy and may mimic blue nevi. Amelanotic metastases are typified by linear serpentine vessels and a white structureless pattern, regardless of the primary tumour.

FIGURE 1

Clinical and dermatoscopical presentations of melanoma CMs. (a, b) Pigmented melanoma CMs showing structureless blue pattern; (c, d) Non-pigmented melanoma CMs revealing structureless white pattern with linear serpentine vessels.

FIGURE 2

Clinical and dermatoscopical presentations of non-melanoma CMs. (a) Non-pigmented breast CM showing structureless white pattern with linear serpentine vessels; (b) Pigmented breast CM showing clods and white lines on structureless brown pattern; (c) Non-pigmented CM of colon adenocarcinoma revelling structureless white pattern with linear serpentine vessels; (d) Non-pigmented CM of rectal adenocarcinoma revealing structureless white pattern with linear serpentine vessels; (e) Non-pigmented CM of renal carcinoma showing structureless white pattern with white lines and linear serpentine vessels; (f) Non-pigmented CM of lung cancer showing structureless white pattern with linear serpentine vessels.