Primary Cutaneous Adenoid Cystic Carcinoma: A Rare Entity

Primary Cutaneous Adenoid Cystic Carcinoma (PCACC) is an uncommon skin adnexal tumour that mostly affects people over 50 years and has no known gender preference. It has no apparent predilection and can appear in a variety of anatomical locations. Less than 200 instances have been reported in the literature so far. Here, we present a case report of cutaneous adenoid cystic carcinoma with unusual location. A 45-year-old male presented with synchronous painful flesh-coloured swellings on the chest and back in a local hospital. These were clinically misdiagnosed as sebaceous cysts. Wide local excision of both swellings was performed, and the samples were sent for histopathology examination. Histology of the swellings revealed an uncommon basaloid adnexal tumour, and the patient was diagnosed with PCACC. PCACC is an important histological diagnosis due to its aggressive tendency to metastasise and recur. Diagnosis of PCACC is primarily based on histopathological examinations, as there are no particular clinical distinguishing features. This case highlights the significance of histological assessment of the mass lesion for proper diagnosis and treatment, as well as thorough examination for PCACC diagnosis post-initial surgery. Here, we report a rare tumour, probably the only case in the literature showing synchronous/bifocal atypical presentation sites.