Naevus sebaceus on the female breast accompanied with a tubular apocrine adenoma and a syringocystadenoma papilliferum

Abstract

Conflicts of interest: none declared. Sir, Tubular apocrine adenoma (TAA) is a very rare sweat gland tumour, first described in 1972.1 It was proposed as an independent clinical entity consisting of a benign appendage tumour of apocrine origin often associated with naevus sebaceus (NS).2 It is commonly located on the face and scalp. We report an unusual case of NS on the breast, which was accompanied with a TAA and a syringocystadenoma papilliferum (SCAP). A 77‐year‐old Japanese woman presented with several cutaneous lesions on her left breast. Physical examination revealed the lesions to consist of light‐brown, slightly elevated, linearly arranged plaques, an ulcerated intracutaneous nodule, and a red pedunculated nodule. The light‐brown plaques had been present since birth. In the plaques, there were small bean‐sized papules and fingertip‐sized, slightly elevated macules, forming a 10 × 4 cm, gently curved lesion as a whole at the upper lateral side of the left breast (Fig. 1, shown by dotted line with thin arrows). Then, 5 months prior to her visit, an asymptomatic, 10‐mm diameter, intracutaneous nodule with central ulceration (Fig. 1, arrow), and a red, 25‐mm diameter, pedunculated nodule resembling a raspberry (Fig. 1, arrowhead) appeared.