Melanoma of the skin is still a tumor with a high mortality associated with late diagnosis of the disease, at the same time it has been established that early diagnosis leads to a complete cure of the tumor in 95—98% of cases. Melanoma can occur both on unchanged skin and on the background of a dysplastic nevus.
OBJECTIVE
Based on our own observations, to identify the clinical features of early melanoma that developed on the basis of a dysplastic nevus.
MATERIAL AND METHODS
In order to prevent melanoma an excisional biopsy of pigmented lesions with a clinical diagnosis of progressive dysplastic nevus is performed in the surgical department of the Central Polyclinic of the Litfond.
RESULTS
In total, from 2009 to January 2020, 178 neoplasms were excised. Histological examination revealed a dysplastic nevus with grade 1—2 of lentiginous melanocytic dysplasia (LMD) in 124 cases, and a progressive nevus with grade 3 LMD in 28 cases. Early melanoma was detected in 17 (9.5%) cases including in 7 cases in situ melanoma. In 7 (41%) of 17 cases the development of melanoma was established on the basis of a dysplastic nevus. A comparative analysis showed that melanoma that developed on the basis dysplastic nevus was localized mainly on the trunk and de novo on the extremities. Differences in age have not been established — regardless of the nature of the process, the patients were predominantly young. In the cases of the development of melanoma on the basis of a dysplastic nevus, in situ melanoma was detected more often than in cases of de novo melanoma. Pigmented lesions in cases of nevus transformation into melanoma in 6 out of 7 cases were large, 0.8—1.5 cm, and had clinical and morphological similarity with Dubreus melanosis from which they differed in localization (trunk), young age of carriers and the presence of nevus cells in the dermis.
CONCLUSION
In the presence of a large dysplastic nevus, it is necessary to refer patients to an oncologist to clarify the diagnosis and determine the tactics of patient management.
