Imaging of palatal lumps

Abstract

Palatal tumours are relatively rare and of variable aetiology, rendering radiological evaluation a daunting process for many. A systematic approach to the imaging of a palatal lump is therefore essential. The hard and soft palates are oral cavity and oropharyngeal structures, respectively. They have different tissue compositions, and therefore, lesions occur with different frequencies at each site. The hard palate has the highest concentration of minor salivary glands in the upper aerodigestive tract and most tumours here are salivary in origin, whereas most tumours at the soft palate are epithelial in origin, i.e., squamous cell carcinomas, in line with other oropharyngeal subsites. The most common malignant tumours of the palate, after squamous cell carcinoma, are minor salivary gland tumours, predominantly adenoid cystic and mucoepidermoid carcinomas. These tumours have a propensity to spread perineurally; understanding the anatomy and imaging features of perineural spread is vital, as it can have significant implications for patient management and tumour resectability. When confronted with a palatal lump, it is important to consider the following: its location on the hard or soft palate; whether it is mucosal or submucosal; the frequently occurring lesions at that site; the most suitable imaging techniques (ultrasound, computed tomography, magnetic resonance imaging); whether there are typical imaging features for any of the common lesions; and whether there are aggressive features, such as bone erosion or perineural spread. This approach allows the radiologist to narrow the differential diagnosis and assist the clinicians with planning treatment.