Nail Unit Melanoma: Uncommon Presentations to Keep in Mind.

Introduction: This article presents a case of nail unit melanoma (NUM), highlighting the unusual clinical presentations as those originating from the hyponychium. We discuss how dermoscopy is an essential tool for this pigmented lesion, and how the lack of a standardized guide for NUM underscores the importance of personalized approaches to ensure the best possible outcomes. Case Presentation: A 72-year-old woman presented with a melanocytic lesion on her right second finger, characterized by a hyperpigmented macule with irregular borders and a heterogeneous distribution of pigment. Biopsy confirmed acral lentiginous melanoma. Nail unit was exercised with a 5-mm margin toward the hyponychium. Conclusion: NUM is the predominant variant of malignant melanoma in certain ethnic groups and is influenced by factors such as trauma and chronic inflammation rather than sun exposure. Despite its higher incidence in areas like the great toe and thumb, NUM in the hyponychium is rare. Detection and treatment require thorough examination and individualized surgical approaches. Conservative surgeries may preserve limb function without compromising survival rates. Early detection remains challenging and necessitates attention to patient concerns and potential signs of melanoma.