Dermatology: Practical and Conceptual Research Letter | Dermatol Pract Concept. 2022;12(2):e2022070 1 Dermatology Practical & Conceptual Introduction Early melanoma diagnosis is a major prognostic factor for improved patient survival. Since its introduction in the der- matological practice, total body photography has proven to be a powerful tool for uncovering new or changing pig- mented lesions that are either too small or unremarkable during a routine clinical skin exam in high-risk individuals [1]. Thanks to this technique, the number of reported mela- nomas measuring less than 2 mm in diameter, defined as mi- cro-melanomas, is increasing. Consequently, the relevance of the 6 mm size criterion of the classic ABCDE rule is currently under question [2]. Case presentation A 29-year-old man with a personal history of melanoma consulted our clinic for his annual skin exam and to- tal-body-photography. The comparative photography re- vealed a new, tiny, pigmented lesion on his right lateral trunk, measuring 1.0 mm x 1.5 mm, and appearing darker than the rest of his naevi (Figure 1, A and B). The digital dermos- copy exam revealed an atypical melanocytic lesion, charac- terized by asymmetry, and irregular network composed of non-uniform streaks of uneven width and borders. There was expansion in an asymmetrical starburst pattern with melanocytic projections of variable sizes and bulging ends with no connection to the lesion, predominating in one extremity of the lesion, and corresponding to pseudopods (Figure 1C). The lesion was excised and the histopatholog- ical analysis revealed an asymmetrical junctional melano- cytic proliferation with nests of various sizes composed of large epithelioid melanocytes with cytologic atypia; pleo- morphic nuclei, dusky and heavily pigmented cytoplasm, and mitotic figures. There was focal lentiginous prolifera- tion in connection with a peripheral nest, compatible with the horizontal expansion seen in the dermoscopic image of irregular streaks, as well as isolated melanocytes in a pag- etoid scatter (Figure 2). Two dermatopathologists reviewed the specimen. Given the lentiginous spread extending over 3 papilla in the periphery of the lesion, and the pagetoid as- cension, which was limited over the nests in the center of the lesion, the diagnosis of melanoma in situ, acral lentiginous subtype, was retained. A re-excision of the scar with 5 mm lateral margins and up to the muscle fascia was performed. We are currently following the patient alternating clinical exam and total body photography every 6 months accord- ing to the Swiss Melanoma guidelines. Birth of a Melanoma Sofia Bogiatzi1, Alessandra Pagnoni1, Daniel Hohl1, Olivier Gaide1 1 Department of Dermatology and Venereology, Lausanne University Hospital (CHUV), Lausanne, Switzerland Key words: dermoscopy, melanoma, total body photography, dermatopathology Citation: Bogiatzi S, Pagnoni A, Hohl D, Gaide O. Birth of a melanoma. Dermatol Pract Concept. 2022;12(2):e2022070. DOI: https://doi.org/10.5826/dpc.1202a70 Accepted: September 2, 2021; Published: April 2022 Copyright: ©2022 Bogiatzi 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: Sofia Bogiatzi, MD-PhD, Department of Dermatology and Venereology, Lausanne University Hospital (CHUV), Avenue Beaumont 29 Lausanne, CH-1011 VD, Switzerland. E-mail: sofia.bogiatzi@chuv.ch 2 Research Letter | Dermatol Pract Concept. 2022;12(2):e2022070 Figure 2. Histopathology correlate revealing features of melanoma in situ. (A-D) 10x magnification sections in different levels of the lesion depicting the asymmetrical melanocytic growth with junctional nests of various sizes, distributed unevenly. (E) 40x magnification of the B section showing the lentiginous spread in contact with a peripheral nest, corresponding to the pseudopods seen in dermoscopy. The me- lanocytes exhibit large nuclei compared to the neighboring keratinocytes with abundant cytoplasm, and heavy pigmentation in some of the cells. No pagetoid scatter was observed in the periphery of the lesion, compatible with an acral lentiginous subtype melanoma. (F) 40x magnification of a central nest with a mitotic figure (red asterisk). (G) 40x magnification of the D section showing interconnected nests in the center of the lesion with scattered melanocytes in the suprabasal layers of the epidermis (green asterisks), compatible with pagetoid ascension. Conclusions Although rare, acral lentiginous melanomas have been re- ported in non-acral sites and their dermoscopic features are similar to the ones observed in our patient. This case illus- trates the success of time-lapse total body photography in the identification of melanomas, akin to witnessing the birth of a star, but also the fine correlation of dermoscopy and pathology. Furthermore, the systematic documentation of micro-melanomas with digital dermoscopy combined with digital pathology and the molecular and genetic profiling of the excised lesions constitute a great opportunity to study these very early events of malignant melanocytic expansion. References 1. Drugge ED, Volpicelli ER, Sarac RM, Strang SR, Elston DM, Drugge RJ. Micromelanomas identified with time-lapse total body photog- raphy and dermoscopy. J Am Acad Dermatol. 2018;78(1):182-183. DOI: 10.1016/j.jaad.2017.07.049. PMID: 29241777. 2. Hornung A, Steeb T, Wessely A et al. The Value of Total Body Photog- raphy for the Early Detection of Melanoma: A Systematic Review. Int J Environ Res Public Health. 2021;18(4):1726. DOI: 10.3390/ ijerph18041726. PMID: 33578996. PMCID: PMC7916771. Figure 1. Total Body Photography exam: a new lesion is identified during time-lapse comparison of photos. (A) Total-body-photography at visit 1. (B) Total-body-photography at visit 2, one year later revealing the presence of a new melanocytic lesion. Inset: high power of the new lesion showing a darker pigmentation than the rest of the nevi. (C) Digital dermoscopy of the new lesion showing an atypical melanocytic network with irregular streaks and pseudopods in an asymmetrical starburst pattern dominating one extremity of the lesion.