Blue naevus with satellitosis mimicking malignant melanoma

Abstract

Blue naevus is an acquired benign melanocytic naevus. It is a firm, sharply defined dark blue to grey-black papule or nodule, which is likely to arise from the arrested dermal melanocytes in the dermis. In the last few years, blue naevus has attracted much attention due to the recognition of new entities and to its confusion with malignant melanoma. We report a 69-year-old man who developed a blue-black nodular lesion with satellitosis on his scalp. Although clinically it was thought to be a malignant melanoma, histopathological investigation and conservative methods such as dermatoscopy and power Doppler ultrasonography did not confirm this diagnosis. Histopathological examination excluded malignant melanoma, as there were no cellular atypia and mitotic activity in either the nodular lesion or the satellitosis. Doppler ultrasonography confirmed the benign nature of the lesion. Dermatoscopic examination showed homogeneous steel-blue pigmentation with individual blue globules, dots and some brown veils, and confirmed the histopathological diagnosis. To the best of our knowledge, our case is the third reported case of a blue naevus with satellitosis mimicking malignant melanoma.

Common Blue Nevus withSatellite Lesions Needs aDifferential Diagnosis from Malignant Melanoma

“…However, in a very small number of cases [1, 2, 3, 4, 5, 6], including our case, a blue nevus can be accompanied by satellite lesions. This is when the physician needs to differentially diagnose it from malignant melanoma, especially the nodular type.…”

“…Malignant blue nevus is rare, and a common blue nevus rarely needs a differential diagnosis from malignant melanoma. Although a melanocytic nevus with a satellite lesion is usually suggestive of a peripherally disseminating malignant melanoma, very few cases of blue nevus with satellite lesions have been reported thus far [1, 2, 3, 4, 5, 6]. To our knowledge, this is the seventh case of a blue nevus with satellitosis.…”

Dermoscopic features of melanoma on the scalp

“…Sahin et al 18 reported a patient presenting a blue to black nodule with satellites on the scalp clinically resembling melanoma. Dermoscopic examination revealed a homogenous blue pigmentation leading to the correct diagnosis of blue nevus with satellites, as confirmed histopathologically.…”

Common blue nevus with satellitosis on the scalp

“…There have been five cases of blue nevus with satellitosis reported to date (7,(11)(12)(13)(14). Table 1 shows the Table 1 -Demographic characteristics of previously reported cases of blue nevus with satellitosis (7,(11)(12)(13)(14).…”