Background: Melanoma is a type of skin cancer that develops from malignant transformations of melanocytes. Its development has been described on congenital melanocytic nevi mainly in relation to its size [1]. However, with the advent of new technologies, especially for aesthetic treatments, changes can occur that simulate malignancy on previous melanocytic lesions, which might lead to uncertainties on the diagnosis and dermatological management. Methods: Descriptive observational study in the form of a case report. We present the case of a 27-year-old patient who had a congenital melanocytic nevus in the cervical region. She noticed changes after undergoing a laser hair removal session on her facial area, which she has been doing for 2 years. Denies any additional treatments. She has no personal medical history, Maintains consistent tanning routine, with more than 3 episodes of sunburn during childhood and adolescence, and the only family medical history is a maternal uncle with unspecified skin cancer. On physical examination, the patient with skin phototype III has an asymmetric plaque in the anterior right cervical region with irregular borders, heterochromia with a predominance of light and dark brown, measuring 20x11 mm. (Fig.1) Results: Given the findings on the physical examination of an atypical lesion, a digital dermoscopy study was requested (Fig.2) : Patient with Skin Phototype: III. Melanocytic lesion located in the right cervical region measuring 20 x 11 mm; with an atypical pseudoreticular pattern with globules and pseudopods in the light brown periphery, hypochromic area with irregular vessels and bright white structures; asymmetry along one axis is observed. Although the findings may be related to regression changes post-laser contact, resection is recommended for histological confirmation. Based on the clinical and dermoscopic findings, it was indicated to proceed with the resection of the lesion and to carry out a pathology study in order to rule out malignancy. The findings of the pathological study were a melanocytic nevus composed of congenital characteristics without signs of malignancy. Conclusions: After laser hair removal on congenital and acquired melanocytic nevi, the clinical appearance, dermoscopy, and histology can be modified, generating doubts for both the doctor and the patient about the possible malignant transformation of these lesions [2]. Therefore, it is important to consider these possible modifications for decision-making regarding follow-up and management. References[1]Scard C, Aubert H, Wargny M, Martin L, Barbarot S., (2023), Risk of melanoma in congenital melanocytic nevi of all sizes: A systematic review., J Eur Acad Dermatol Venereol JEADV, 32-9., 37(1)[2]Acle R, Zambrano-Mericq MJ, Navarrete-Dechent C, Uribe P, Abarzúa-Araya Á., (2022), Clinical and dermoscopic evaluation of melanocytic nevi changes during diode laser hair removal: A prospective study, Lasers Surg Med, Lasers Surg Med, 970-7., 54(7)