1. Blue nevus and cellular blue nevusA
Blue nevus and cellular blue nevusA. This blue nevus has regular borders but is not circular and is solidly blue-black in color. The epidermis is smooth, indicating that the lesion is in the dermis. The consistency is increased and the margins are well defined. Differential diagnosis must include nodular melanoma. If the lesion has been present for years, a biopsy is not necessary. If the lesion was noted only a few months ago, excision biopsies are required to rule out nodular melanoma. However, dermoscopy greatly facilitates the clinical differential diagnosis showing none of the features of nodular melanoma and will therefore render an excisional biopsy unnecessary. B. This cellular blue nevus appeared as two large, bluish-black nodules on the scalp. After excision, histology showed that they were contiguous and thus represented one single lesion. Cellular blue nevi are much larger and should always be excised to rule out melanoma, which, albeit rarely, can develop in these lesions.
Source: Section 9. Benign Neoplasms and Hyperplasias, Fitzpatrick's Color Atlas & Synopsis of Clinical Dermatology, 6e
Citation: Wolff K, Johnson R. Fitzpatrick's Color Atlas & Synopsis of Clinical Dermatology, 6e; 2009 Available at: Accessed: October 18, 2017
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