Salivary Neoplasms Classification

Classification of Salivary Neoplasms

• Benign salivary neoplasms:
• Pleomorphic adenoma (mixed salivary tumor)
• Monomorphic adenoma
• Warthin's tumor (adenolymphoma)
• Oncocytoma (oxyphil adenoma)
• Malignant salivary neoplasms:
• Mucoepidermoid carcinoma
• Adenoid cystic carcinoma (cylindroma)
• Acinic cell carcinoma
• Adenocarcinoma
• Carcinoma ex pleomorphic adenoma
• Epidermoid carcinoma (squamous cell carcinoma)
• Lymphoma

Pathology of Benign Salivary Neoplasms

• Pleomorphic adenoma (mixed parotid tumor):
• Represent 75% of parotid and 50% of submandibular gland neoplasms
• Equal distribution between males and females
• Occurs in the fourth decade of life, but any age and sex may be affected
• Pathology:
• Epithelial, myoepithelial, and stromal components
• Incomplete capsule, allowing extension of neoplastic epithelium into surrounding tissues
• Slow growth, non-infiltrating the facial nerve
• Rarely turns into carcinoma after 10 years

Warthin's Tumor (Adenolymphoma)

• Found in the lower part of the parotid gland
• Loss of superficial temporal pulse
• Typically raises the lobule of the ear and does not affect the facial nerve

Differential Diagnosis

• Extra parotid swellings:
• Lymph nodes, sebaceous cysts, and lipomas may resemble pleomorphic adenomas
• Mandibular, maxillary, and infratemporal fossa tumors may produce false appearance of parotid enlargement
• Hypertrophy of the masseter is bilateral in most cases

Investigations

• Not routine, as clinical diagnosis is reliable enough for most cases
• Biopsy:
• FNAC is allowed, but requires an expert cytopathologist
• Open surgical biopsy of major salivary glands is contraindicated
• Neck US
• CT-scan and MRI: to show the extent of the tumor
• Isotope scanning with technetium: salivary neoplasm shows as a cold spot, adenolymphoma and oncocytoma show as hot spots

Treatment

• Surgery is the only reliable form of treatment for salivary neoplasms

Clinical Picture of Benign Salivary Neoplasms

• Symptoms:
• Painless, slowly growing swelling in the parotid region
• Signs:
• Swelling over the angle of the mandible
• Elevates the lobule of the ear
• Swelling is superficial to the masseter muscle
• Facial nerve is not affected by the tumor

Clinical Picture of Benign Salivary Neoplasms (Palpation)

• Swelling is not hot, not tender, not attached to the skin, masseter, or mandible
• Swelling is well-defined
• Consistency: varies from firm to cystic (but never hard)
• Pulsation of the superficial temporal artery is normal

Clinical Picture of Carcinoma of the Parotid

• Symptoms:
• Steadily enlarging swelling on the side of the face
• Salivary malignancies do not usually grow as fast as other cancers
• Swelling is sometimes painful, with pain radiating to the ear and intensified by mastication
• Signs:
• Mass is usually warm and mildly tender
• Firm or hard and has an irregular surface
• May be adherent to the skin, masseter, or mandible
• If the tumor infiltrates the facial nerve, there is weakness or paralysis of the facial muscles
• Cervical lymph nodes are sometimes involved
• Rarely, these tumors metastasize to the lungs

This quiz covers the classification of salivary neoplasms, including benign and malignant tumors. Learn about the different types of salivary gland tumors and their characteristics.