Primary cutaneous adenoid cystic carcinoma arising in the scalp: a diagnostic challenge.

Primary cutaneous adenoid cystic carcinoma (PCACC) is a rare adnexal tumour of the skin, predominantly affecting individuals over 50 years of age, with no established gender predilection. It can arise on various anatomical sites without a clear preference. To date, fewer than 200 cases have been documented in the literature.We present a case of a young, otherwise healthy female who developed a slow-growing painless, skin-coloured scalp nodule. Histopathological examination of an excisional biopsy revealed a dermal tumour composed of basaloid cells arranged in a characteristic cribriform pattern. A thorough diagnostic workup, including sonographic imaging, immunohistochemical analysis and multidisciplinary team discussions, ultimately confirmed the diagnosis of PCACC. This case underscores the diagnostic and therapeutic challenges associated with PCACC.