From the Guidelines
The parotid gland is the most common site for major salivary gland tumors, accounting for approximately 70% of cases, and the majority of these tumors are benign, with pleomorphic adenoma being the most common type 1. When evaluating the parotid gland, it is essential to consider the potential for both benign and malignant tumors, as well as other conditions such as mumps, salivary stones, and autoimmune disorders. The parotid gland plays a crucial role in digestion by secreting amylase-rich saliva that begins breaking down starches in the mouth. It has a unique anatomical feature in that the facial nerve (cranial nerve VII) passes through it, dividing the gland into superficial and deep lobes. This relationship is particularly important during surgical procedures in this area, as damage to the facial nerve can result in facial muscle paralysis. The risk of malignancy is inversely proportional to the size of the gland, with the sublingual gland having a higher risk of cancer compared to the parotid gland 1. Patients with parotid gland tumors or other conditions may present with a palpable abnormality, pain, or weakness of the facial muscles, and should be evaluated by a healthcare professional to determine the underlying cause and appropriate treatment. Imaging studies, such as MRI, may be used to assess the extent of the tumor and plan for surgical intervention, with MRI offering superior soft tissue contrast resolution and the ability to delineate the soft tissue extent of the tumor 1.
From the Research
Parotid Gland Infections
- The parotid gland is most commonly affected by an inflammatory process among all the salivary glands 2
- Infections of the parotid gland can range from acute to severe and can be caused by various factors, including viral and bacterial infections
- Viral parotitis can be caused by paramyxovirus (mumps), Epstein-Barr virus, coxsackievirus, and influenza A and parainfluenza viruses 2
- Acute suppurative parotitis is generally caused by Staphylococcus aureus, Streptococcus species, and rarely, gram-negative bacteria 2
Diagnosis and Management
- A specific and regimented approach to the diagnosis and management of patients with disease of the parotid gland is necessary for correct diagnosis and management 3
- Patient morbidity or mortality may result if there is a delay in the diagnosis of a malignant parotid tumor 3
- Sialography remains the investigation of choice for chronic parotitis, but diagnostic siladenoscopy may complement or supersede sialography as the diagnostic procedure of choice 4
- Management options for chronic parotitis are conservative or surgical, but controversy exists regarding the timing and method of surgical intervention 4
Symptoms and Signs
- Symptoms and signs of parotid tumors, such as pain/tenderness, adhesion to surrounding tissues, and facial nerve palsy, are useful for the differentiation of benign versus malignant tumors and may also be of value to determine the grade of malignancy and histological type as well as the assessment of prognosis 5
- The incidence of symptoms and signs is significantly higher in malignant than benign tumors, and more frequent in higher grade of malignancy 5
- Facial nerve palsy is observed in 18.0% of malignant tumor cases, while none occurred in benign tumor cases 5
Chronic Parotitis
- Chronic parotitis is a nonspecific sialadenitis that often is seen first in the dental office 6
- The cause of chronic parotitis is most likely multifactorial and includes decreased salivation, stasis and an ascending retrograde duct infection 6
- Diagnosis is based on history, clinical examination, salivary volume and chemistry, computerized tomographic scan and sialography 6
- Treatment is palliative in nature, and early clinical recognition of chronic parotitis leads to appropriate and successful care 6