Salivary Gland Diseases in Children and Adolescents

Introduction Salivary glands are found in and around the oral cavity, and they are divided into major and minor salivary glands. The major salivary glands are the parotid, submandibular, and sublingual glands; the minor salivary glands are located in the lips, buccal mucosa, palate, and throat. Generally, salivary gland diseases are not common in the paediatric population. The classification of salivary gland diseases is very complex because it encompasses different entities; however, precise classification and terminology are necessary for accurate diagnosis and management. As in adults, diseases of the salivary glands may be nonneoplastic or neoplastic (tumours) (Table 39.1). The pattern of incidence in the paediatric population differs greatly from that in the adult group. Most salivary gland lesions in children are either inflammatory or vascular in origin. Of the developmental salivary gland diseases, haemangiomas are the most common. In the African paediatric population, mumps is the most common in the inflammatory/infection group, but in the developed world, only sporadic cases of mumps are now reported, and rhabdomyosarcomas are the most common nonodontogenic mesenchymal tumours in children. Neoplastic changes in the paediatric population are very rare compared to the inflammatory groups. In the population as a whole, salivary gland neoplasms constitute 2.8% of all head and neck tumours, but in children it accounts for about 10% of all childhood neoplasms and between 3% and 22% of epithelial salivary gland neoplasms. The majority (88.5%) of salivary gland tumours are benign; the remaining 11.5% being malignant. In children, the most common benign epithelial tumour is pleomorphic adenoma, and the most common malignant tumour is mucoepidermoid carcinoma. Salivary gland tumours in children have the same clinical and biologic behavior as those in the adult. The majority (76.7%) occur in the major glands, with the remainder in the minor glands, a ratio of 3.3:1. The ratio of occurrence of parotid to submandibular to sublingual tumours in the major salivary glands is 30:6:1. Globally, these tumours occur predominantly in girls and at any childhood age. A detailed clinical history with imaging features narrows the differential diagnosis while providing useful information for management and prognosis. Incisional biopsy must be avoided due to the possibility of tumour spillage and facial nerve damage. The treatment of salivary gland diseases is categorised into medical and surgical, depending on the nature of the disease condition. The neoplastic lesions usually require surgical intervention, with or without radiation and chemotherapy, whereas the nonneoplastic/inflammatory diseases are managed symptomatically and conservatively. A protracted conservative medical management is strongly advised, however, before surgical ablation is considered in children.