Dermatology: Practical and Conceptual Image Letter | Dermatol Pract Concept. 2025;15(4):6050 1 Poroma Vessels can be Better Identified by High Magnification Dermoscopy Compared to Conventional Dermoscopy Roberta Giuffrida1, Linda Tognetti2, Dario Valguarnera1, Claudio Conforti3-4, Iris Zalaudek5*, Fabrizio Guarneri1* 1 Department of Clinical and Experimental Medicine, Dermatology, University of Messina, Messina, Italy 2 Dermatology Unit, Department of Medical, Surgical and Neurosciences, University of Siena, Siena, Italy 3 IDI-IRCCS, Dermatological Research Hospital, Rome, Italy 4 Department of Life Science, Health, and Health Professions, Link University of Rome, Rome, Italy 5 Department of Dermatology and Venereology, University of Trieste, Ospedale Maggiore, Trieste, Italy *Equally contributed to the manuscript Key words: Magnified Dermoscopy, Poroma Citation: Giuffrida R, Tognetti L, Valguarnera D, Conforti C, Zalaudek I, Guarneri F. Poroma Vessels can be Better Identified by High Magnification Dermoscopy compared to Conventional Dermoscopy. Dermatol Pract Concept. 2025;15(4):6050. DOI: https://doi.org/10.5826/dpc.1504a6050 Accepted: June 2, 2025; Published: October 2025 Copyright: ©2025 Giuffrida et al. This is an open-access article distributed under the terms of the Creative Commons Attribution- NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited. Funding: None. Competing Interests: None. Authorship: All authors have contributed significantly to this publication. Corresponding Author: Dr. Roberta Giuffrida, MD, PhD. Department of Clinical and Experimental Medicine, Dermatology, University of Messina, Italy. Institute of Dermatology c/o “G. Martino” University Hospital, via Consolare Valeria n°1, 98125 Messina, Italy. ORCID ID: 0000-0002-5492-3033. Email: giuffrida.roberta@unime.it Case Presentation An 88-year-old female with history of multiple basal cell carcinomas (BCCs) presented with an asymptomatic, pink-to-red 2-mm firm papule on her left posterior leg of two months’ duration. Dermoscopy at magnification 20x (Medicam 1000, Fotofinder System, Bad Birnbach, Ger- many) showed yellow central structureless area, surrounded by white interlacing areas around polymorphous vessels (Figure 1A). The latter at magnification 300x (Fig.1b) and 400x (Fig.1c) better appeared as branched vessels with rounded endings. Histopathologic examination revealed fea- tures compatible with eccrine poroma. Teaching Point Eccrine poroma (EP) is an uncommon, benign sweat gland tumor that clinically may show a variety of features, mimick- ing other neoplasms [1]. The most frequent clinical presen- tation is a single slow-growing, asymptomatic pink-to-red well-circumscribed papule or nodule, commonly affecting the distal extremities of adult patients [1]. 2 Image Letter | Dermatol Pract Concept. 2025;15(4):6050 Dermoscopy improves the diagnosis of EP, typically show- ing a polymorphous vascular pattern, including branched vessels with rounded endings (branched vessels with looped/ coiled terminal endings having a rounded silhouette), consid- ered a clue for EP [1]. However, this finding was recently de- scribed in BCC, frequently reported as differential diagnosis of EP [2]. Of note, in EP the vessels are generally less prominent and branched than in BCC. This peculiar vascular morphol- ogy may be difficult to detect with conventional dermoscopy. High magnification dermoscopy is a new noninvasive imag- ing tool that has been shown to add information for clinically difficult-to-diagnose skin tumors. It may be useful to better identify branched vessels with rounded endings in EP, improv- ing the diagnostic accuracy compared to dermoscopy with low magnification. Figure 1. Dermoscopy of eccrine poroma. A) Yellow central structureless area, surrounded by white interlacing areas around polymorphous vessels visible at magnification 20x. B-C) Branched vessels with rounded endings well visible at magnification 300x (B) and 400x (C). Ethics Statement: The patient in this manuscript gave written informed consent to the publication of her case details. References 1. Marchetti MA, Marino ML, Virmani P, et al. Dermoscopic features and patterns of poromas: a multicentre observational case-control study conducted by the International Dermoscopy Society. J Eur Acad Dermatol Venereol. 2018;32:1263-1271. DOI: 10.1111/jdv.14729. PMID: 29194789. 2. Cavallo F, Mazzoletti V, Zelin E, et al. ‘Poroma-like’ branched vessels with rounded endings in dermoscopy of basal cell car- cinoma: a new unusual structure. Clin Exp Dermatol. 2023; 48:1177-1179. DOI: 10.1093/ced/llad225. PMID: 37401454.