Basalioma in a nevus sebaceous of the scalp

We present the case of a 56-year-old woman with a congenital yellowish lesion on her scalp that had remained stable until approximately 18 months before evaluation.During this period, she noted the appearance of new growths on the lesion, which exhibited progressive enlargement and occasional spontaneous bleeding.On physical examination, a sessile, yellowbrown, verrucous plaque with well-defined, irregular borders, measuring approximately 4 1.5 cm, was observed on the interparietal scalp (Fig. 1).At the anterior margin of the plaque, a violaceous nodule with macroscopic telangiectasias, measuring approximately 1.5 cm in its greatest dimension, was identified (Fig. 1).Posterior to this, an 8-mm violaceous papule with similar features was noted (Fig. 1).Dermoscopy revealed telangiectasias and a bluish coloration (Fig. 2).Surgical excision of both lesions was performed, and histopathological examination confirmed basal cell carcinoma (BCC) arising within a nevus sebaceous, with clear surgical margins.Nevus sebaceous, also known as nevus sebaceous of Jadassohn, is a hamartomatous lesion originating from follicular, sebaceous, apocrine, and connective tissue components 1,2 .These lesions typically present at birth or in early childhood, often as yellow to orange patches or plaques with associated alopecia 1 .While the scalp is the most common site, nevus sebaceous can also occur on the face, neck, and other regions 1 .