*Review* **Current Challenges in Deciphering Sutton Nevi—Literature Review and Personal Experience**

**Roxana Nedelcu 1,2 , Alexandra Dobre 1, \* , Alice Brinzea 1,2,3 , Ionela Hulea 1 , Razvan Andrei 4,5 , Sabina Zurac 1,4 , Mihaela Balaban 2 , Mihaela Antohe 1,2 , Lorena Manea 1,4,6 , Andreea Calinescu 1,2 , Anastasia Coman 1,2 , Florentina Pantelimon 2 , Adina Dobritoiu 2 , Catalin Popescu 1,4 , Raluca Popescu 1,4 , Elena Balasescu 1 , Daniela Ion <sup>1</sup> and Gabriela Turcu 1,2,4**


**Abstract:** Halo nevi, known as leukoderma acquisitum centrifugum, Sutton nevus, leukopigmentary nevus, perinevoid vitiligo, or perinevoid leukoderma, together with vitiligo and melanomaassociated hypopigmentation, belong to the group of dermatoses designated as immunological leukodermas. The etiology and pathogenesis of halo nevi has not been fully elucidated. There are several mechanisms through which a lymphocytic infiltrate can induce tumoral regression. In this review, we aimed to update the knowledge about Sutton nevi starting with the clinical appearance and dermoscopic features, continuing with information regarding conventional microscopy, immunohistochemistry, and the immunological mechanisms responsible for the occurrence of halo nevi. We also included in the article original unpublished results when discussing dermoscopic, pathologic and immunohistochemical results in halo nevi. Sutton nevi are valuable models for studying antitumor reactions that the human body can generate. The slow and effective mechanism against a melanocytic skin tumor can teach us important lessons about both autoimmune diseases and anticancer defenses.

**Keywords:** immune response; inflammation; Sutton nevi; halo nevi; skin tumor
