Rare Tumour - Sebaceous Carcinoma of the Scalp

Abstract

Sebaceous carcinoma (SC) is a rare carcinoma arising from sebaceous gland divided into ocular and extra ocular. Ocular SC is more common than extra ocular. This tumour has a high incidence of recurrence and metastasis. Due to its rarity, it is often difficult to arrive to a diagnosis. Early diagnosis and treatment is crucial. Definitive diagnosis is only by histopathological examination. We are presenting a case of sebaceous carcinoma arising from the scalp. I. Introduction Sebaceous carcinoma (SC) is a rare aggressive malignant tumour derived from the adnexal epithelium of sebaceous glands. It is most commonly seen in the orbital region(2). Extra orbital sebaceous cell carcinoma is extremely rare which commonly occurs on head and scalp due to the abundant sebaceous glands(3). Most sebaceous gland carcinomas have no obvious aetiology and only a few are associated with Muir-Torre syndrome(MTS). This tumour is thought to arise from sebaceous glands in the skin and thus, may crop up anywhere in the body, where these glands exist including the genitalia. SCtraditionally classified into 2 groups, those arising from the ocular adnexa, particularly the Meibomian glands and glands of Zeiss, and those arising in extra ocular sites(4). Ocular SC represents 0.2% to 0.8% of all eyelid tumours and 1% to 5.5% of all eyelid malignancies(6). It is estimated that approximately 25% of all reported cases of sebaceous carcinoma occur in extra ocular site. It has been reported that more than 70% of sebaceous carcinomas are located in the head and neck regions, where sebaceous glands are most commonly located (5).These tumours have a high incidence of local recurrence and regional metastasis. Earlydiagnosis is crucial in reducing the morbidity and mortality associated with the tumour(6). This is a case report of an elderly manwith a sebaceous carcinoma of the scalp.