Basal Cell Adenocarcinoma of the Parotid and Its Simulating Differentials -A Case report

Abstract

Basal Cell Adenocarcinoma (BCAC) is a rare tumour of the salivary glands which has recently been included in the World Health Organization classification. It is thought to be malignant counterpart of basal cell adenoma (BCA) from which it can only be distinguished on the basis of its infiltrative growth pattern and lymphovascular and perineural invasion. Other important tumours like adenoid cystic carcinoma etc also need to be kept in the differential diagnosis. Owing to its rarity, its resemblance to the benign BCA and the fact that it has to be differentiated from more aggressive tumours, it is important to identify and diagnose BCAC. We thus present a case of BCAC in parotid with a review of literature and a discussion of the important differential diagnoses.

Basal cell adenocarcinoma of the tongue- A rarity Case report

“…Later in 1990 Ellis and Wiscivitch described the clinical and pathological features of the lesion [5,7]. BCAC is a rare salivary gland neoplasm with an unknown etiology, although some researchers claim that the tumour arises from pluripotent ductal epithelial cells or from reserve cells [1,5,6]. While a small portion of the lesions present with pain or tenderness, a vast majority occur as asymptomatic freely moveable swelling with a time period before diagnosis ranging from weeks to years.…”

“…World Health Organisation (WHO) classified basal cell adenocarcinoma (BCAC) as a salivary gland tumour in 1991 and in 2005 categorised it as a low-grade malignancy [1]. Historically it has been termed under several names such as malignant basal cell adenoma, carcinoma ex monomorphic adenoma and basaloid salivary carcinoma [2].…”

“…Historically it has been termed under several names such as malignant basal cell adenoma, carcinoma ex monomorphic adenoma and basaloid salivary carcinoma [2]. Although some researchers claim that the lesion arises from previously existing basal cell adenoma while others claim that it arises de novo, the exact histogenesis is still unknown [1].…”

“…BCAC constitutes 1.6% of these salivary gland tumours and 29% of all malignant salivary gland tumours. A vast majority (90%) of BCAC originate from the parotid glands while submandibular and minor salivary gland BCAC make up a small percentage [1,5,6]. When the parotid is involved, it is usually seen in the superficial lobe of the gland [7].…”

“…Some researchers claim a slight male preponderance while others claim that the lesion affects both genders equally [1,4]. 3-4% of all head and neck tumours are salivary gland tumours.…”