Clinical Significance of Benign Nevus Regression

Understanding Nevus Regression

Benign congenital and acquired melanocytic nevi can undergo spontaneous lightening and depigmentation as a normal phenomenon 1
Changes in pigmentation pattern, including becoming more mottled, speckled, or showing homogeneous or heterogeneous lightening, are recognized benign changes 2
Textural changes, such as becoming more raised, verrucous, or papillated, represent normal evolution 2

The presence of regression in a melanocytic lesion is a mandatory histopathological parameter that must be documented, as recommended by the NIH consensus conference and French Consensus Conference criteria for melanoma assessment 3
The American Academy of Dermatology and other guideline societies imply that complete excisional biopsy is essential for lesions with concerning features, rather than clinical observation alone, to assess all histological parameters, particularly when regression is present 3, 4, 5, 6
Excisional biopsy with scalpel, rather than laser or electro-coagulation, is recommended to prevent tissue destruction and ensure accurate diagnosis 3, 4, 5

Congenital melanocytic nevi carry a lifetime melanoma risk of 0.7-1.7%, emphasizing the need for careful evaluation and complete excision when changes occur 1
Melanoma in congenital nevi can present as deep nodules without overlying color change, highlighting the importance of palpation and complete excision 2
The expected histopathology report should include confirmation of melanocytic nature, presence and extent of regression, Breslow thickness if melanoma, margin assessment, and presence of ulceration 3, 4, 8