Dermatology: Practical and Conceptual Letter | Dermatol Pract Concept 2021;11(2):e2021027 1 Dermatology Practical & Conceptual Dermoscopy of a Lentigo Maligna Less Than 1.5 mm in Diameter Karim Saleh1 1 Division of Dermatology and Venereology, Department of Clinical Sciences, Lund University, Skåne University Hospital, Lund, Sweden Key words: lentigo maligna, angulated lines, micromelanoma, dermoscopy Citation: Saleh K. Dermoscopy of a lentigo maligna less than 1.5 mm in diameter. Dermatol Pract Concept. 2021;11(2):e2021027. DOI: https://doi.org/10.5826/dpc.1102a27 Accepted: September 29, 2020; Published: March 8, 2021 Copyright: ©2021 Saleh. This is an open-access article distributed under the terms of the Creative Commons Attribution License BY- NC-4.0, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: None. Competing interests: The author has no conflicts of interest to disclose. Authorship: The author takes responsibility for this publication. Corresponding author: Karim Saleh, MD, PhD, Division of Dermatology, Department of Clinical Sciences, Biomedical Center B14, Lund University, Tornavägen 10, SE-221 84 Lund, Sweden.  Email: Karim.Saleh@med.lu.se Introduction We report the smallest lentigo maligna (LM) detected by physical examination and dermoscopy (1.4 mm in diameter dermoscopically and 1.3 mm histologically) in a 74-year-old woman who presented to our clinic. Case Presentation The patient had a history of melanoma on her left arm in 2018. She visited for a regular check-up. She had not been monitored with total body photography. During physical examination a tiny lesion next to telangiectasias on her left cheek was noted. She was not aware of this lesion due to its tiny size. Dermoscopy revealed sun-damaged skin with telangiectasias surrounding a 1.4-mm pattern of light brown dots forming angulated lines (Figure 1). Lentigo maligna was suspected and the lesion excised. Histopathology confirmed the diagnosis of a lentigo maligna (Figure 2). Conclusions Angulated lines in facial lesions are early features that can indicate lentigo maligna [1]. These lines have previously been referred to as the zigzag pattern or rhomboidal struc- tures. Akay et al. [2] documented the smallest melanoma ever published that measured 0.9 mm. However, that lesion was detected using a total-body imaging system. The lesion here is the smallest lesion detected by physical examination without the aid of an imaging system, and to the best of the author’s knowledge, the smallest lentigo maligna lesion ever published. 2 Letter | Dermatol Pract Concept 2021;11(2):e2021027 References 1. Schiffner R, Schiffner-Rohe J, Vogt T, et al. Improvement of early recognition of lentigo maligna using dermatoscopy. J Am Acad Dermatol. 2000;42(1 Pt 1):25-32. DOI: 10.1016/s0190- 9622(00)90005-7. PMID: 10607316. 2. Akay BN, Okcu Heper A, Clark S, Erdem C, Rosendahl CO, Kit- tler H. Dermatoscopy of a melanoma less than one millimeter in diameter. Int J Dermatol. 2017;56(12):1498-1499. DOI: 10.1111/ ijd.13728. PMID: 28857145. Figure 1. (A) Clinical photograph of the left cheek. (B) Polarized contact dermoscopy of the lesion. Figure 2. (A) Microscopic sections with H&E stain show an asym- metrical proliferation of melanocytes organized in nests that vary in size and distribution (×10) with a subepithelial actinic elastosis and telangiectatic vessels. Lesion size was 1.3 mm. (B) The same section at ×25. (C) SOX-10 stain illustrating periadnexal extension.