What is the most common parotid (salivary gland) mass?

From the Guidelines

The most common parotid mass is a pleomorphic adenoma, which accounts for approximately 60%-70% of all parotid tumors. This is based on the most recent evidence from 2023, which highlights the prevalence of benign tumors in the parotid gland, with pleomorphic adenoma being the most common subtype 1. The parotid gland is the most common site for salivary gland tumors, and the majority of these tumors are benign, with pleomorphic adenoma and Warthin tumor being the most common benign subtypes.

Key Characteristics of Pleomorphic Adenoma

• Accounts for 60%-70% of all parotid tumors
• Typically presents as a slow-growing, painless, firm mass in the parotid gland region
• More common in women than men
• Usually occurs between the ages of 30 and 60
• Characterized by a mixed histological appearance, containing both epithelial and mesenchymal elements Some key points to consider when evaluating parotid masses include:
• 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
• The majority of parotid tumors are benign, but a smaller percentage are malignant, with mucoepidermoid carcinoma, adenoid cystic carcinoma, lymphoma, and acinic cell carcinoma being the most common subtypes
• Patients typically present with a palpable abnormality or pain, and perineural spread of disease can cause weakness of the facial muscles Surgical removal of pleomorphic adenomas is recommended due to their potential for malignant transformation, with a standard treatment of superficial parotidectomy with preservation of the facial nerve. Early diagnosis and complete surgical excision are crucial to prevent complications such as facial nerve damage or malignant transformation, as highlighted in the recent study 1.

From the Research

Most Common Parotid Mass

• The most common parotid mass is pleomorphic adenoma, accounting for 60 to 70 percent of all benign salivary gland tumors 2.
• Pleomorphic adenoma is a slow-growing, painless mass that usually presents inferior to the pinna of the ear 2.
• The diagnosis of pleomorphic adenoma is based on clinical presentation, magnetic resonance imaging or computed tomography, and fine-needle aspiration biopsy 2.
• Treatment of pleomorphic adenoma involves wide excision, where the entire capsule is removed, but the facial nerve is spared 2.

Characteristics of Pleomorphic Adenoma

• Pleomorphic adenoma is the most common tumor of the parotid gland in both adults and children 3, 4.
• The most common presentation of pleomorphic adenoma is an asymptomatic mass 3, 4.
• Preoperative evaluation with MRI or CT scan can be helpful in determining the extent of the lesion and surgical planning 3.
• Complete excision via superficial or total parotidectomy with preservation of the facial nerve is the treatment of choice for pleomorphic adenoma 3, 4.

Importance of Early Diagnosis and Treatment

• Early diagnosis and treatment of pleomorphic adenoma are crucial to prevent complications such as tumor recurrence and malignant transformation 2, 5.
• Carcinoma ex pleomorphic adenoma, a malignant transformation of pleomorphic adenoma, has a high recurrence rate and requires proper diagnosis and treatment 6.
• Surgical removal of the tumor mass is the ideal management for pleomorphic adenoma, and complete removal of the tumor without remnants is crucial to prevent recurrence 5.