A primary cutaneous adenoid-cystic carcinoma in a young woman. Differential diagnosis and clinical implications

Abstract

Primary cutaneous adenoid-cystic carcinoma (PCACC) is a rare slow-growing neoplasm of disputed histogenesis characterized by a cribriform pattern at histology and local aggressive behaviour. Up to date about 60 cases of PCACC have been reported in the literature. This tumour is most common in the scalp, affects middle-aged and older individuals (mean age 59) and has predilection for women. We describe an unexpected case of PCACC in a 32-years-old woman referred to our clinic for a subcutaneous nodule in the scalp showing a slow growth and indolent course. The differential diagnosis and the clinical management of this PCACC patient, successfully treated with a wide local excision, are presented and discussed.

Keywords: differential diagnosis.; primary cutaneous adenoid-cystic carcinoma; rare skin tumours.

Figure 1

The clinical picture of the scalp lesion with associated alopecia.

Figure 2

Histological and immunohistochemical features of a primary cutaneous adenoid cystic carcinoma A) Low power view of the tumour demonstrating a poorly circumscribed neoplasm, which is composed of collection of basophilic cells with cribriform pattern. B) Higher magnification of the lesion showing tumour nests surrounded by an eosinophilic stroma. Nuclear palisading and epidermal contact are absent. C) Immunostaining with mAb to EMA depicts the apical aspect of pseudoglandular spaces. D) The hyaline deposits in small luminal areas among the basophilic cells are immunoreactive with mAb to collagen IV.