Vascular structures in skin tumors: a dermoscopy study.

OBJECTIVES To describe the different vascular structures seen by dermoscopy and to evaluate their association with various melanocytic and nonmelanocytic skin tumors in a large series of cases. DESIGN Digital dermoscopic images of the lesions were evaluated for the presence of various morphologic types of vessels. SETTING Specialized university clinic. PATIENTS From a larger database, 531 excised lesions (from 517 patients) dermoscopically showing any type of vascular structures were included. MAIN OUTCOME MEASURES The frequency and positive predictive value of the different vascular structures seen in various tumors were calculated, and the differences were evaluated by the chi2 or Fisher exact test. RESULTS Arborizing vessels were seen in 82.1% of basal cell carcinomas, with a 94.1% positive predictive value (P<.001). Dotted vessels were generally predictive for a melanocytic lesion (90.0%, P<.001), and were especially seen in Spitz nevi (77.8% of lesions). In melanoma, linear-irregular, dotted, and polymorphous/atypical vessels were the most frequent vascular structures, whereas milky-red globules/areas were the most predictive ones (77.8%, P = .003). The presence of erythema was most predictive for Clark nevus, whereas comma, glomerular, crown, and hairpin vessels were significantly associated with dermal/congenital nevi, Bowen disease, sebaceous hyperplasia, and seborrheic keratosis, respectively (P<.001 for all). CONCLUSIONS Different morphologic types of vessels are associated with different melanocytic or nonmelanocytic skin tumors. Therefore, the recognition of distinctive vascular structures may be helpful for diagnostic purposes, especially when the classic pigmented dermoscopic structures are lacking.