Benign Salivary Gland Tumors

Question 1

Benign Salivary Gland Tumors

Answer 1

1. Pleomorphic Adenomas (Mixed Tumor) 2. Monomorphic Adenomas (Canalicular Adenoma & Basal Cell Adenoma) 3 . Warthin Tumor (Papillary Cystadenoma Lymphomatosum)

Question 2

Pleomorphic Adenoma (Mixed Tumor)

Answer 2

• Most common SG Tumor
• Painless, slow growing, firm mass
• Adults (30-50 years old), slight female predilection
• Sites:
  
  • 50-70% parotid tumors
  • minor SG: PALATE > upper lip> buccal mucosa >other sites
  • MOST COMMON INTRAORAL SITE IS PALATE
• TREATMENT: Surgical Excision
• Malignant transformation possible in long standing lesions (about 5% cases)- Ca ex PA

Question 3

What are large swellings, commonly seen on the lateral side of the palate?

They are slow growing and benign – but they can grow to enormous sizes

Answer 3

Pleomorphic Adenoma – MIXED TUMOR

Question 4

Pleomorphic Histology

Answer 4

Proliferation of mile epithelial cells in the palate

• Mixed tumor with myxoid component and fibrous epithelial component
• Mixed Tumor with cartilage (upper left) and bone (dark blue) differentiation
• Ductal differentiation
• Plasmacytoid cells

Question 5

Canalicular Adenoma

Answer 5

Almost exclucively in MINOR SG

• Upper Lip (>75%)
• Older Adults
• Slow growing, painless mass

Question 6

Canalicular Ademoma Images

Answer 6

Clue: Swelling is quite subtitle, the early stages can see swelling areas has increased vascularity and the bluish tint to it

• Salivary gland tumors in differential
• Can see bluish changes much more pronounced
• Mucosal can present with similar presentation (more common on lower lip)
• UPPER LIP

Question 7

Canalicular Adenoma

Answer 7

• Single layered cords of columnar or cuboidal epithelial cells with deeply basophilic nuclei
• Bilayered appearance of tumor cords

Question 8

Basal Cell Adenoma

Answer 8

• Basaloid appearance of Tumor cells
• Primary parotid lesion

Basal Cell Adenoma Tubular & Solid Pattern

• Basal cells are located in the epithelium the lower, adjacent to the interface of the connective tissue
• they are separated by the basement membrane, and they can differentiate
• stem cells of the epithelium is located in the basal layer
• they can divide into two - one cell remains in the basal layer of the epithelium, the other daughter cell undergoes a different process of differentiation and it goes into a spinal cell and it goes into the spinous layer and then it differentiates into a granular cell - finally it is a terminally differentiated cells that is sloughed off from the surface
• B - B: Basal Blue – very blue in appearance
• very cuboidal in appearance

Question 9

Papillary Cystadenoma Lymphomatosum

(Warthin Tumor)

Etiology

Answer 9

Though to arise within lymph nosed as a result of entrapment of salivary gland elements early in edevelopment

• Majority in Parotid Gland
• Rare Intraorally !!!!
• Men
• 5th - 8th decade (60s - 90s)

Question 10

Papillary Cystadenoma Lymphomatosum (Warthin Tumor)

Clinical Features / Histopathological Features

Treatment

Answer 10

• Doughy to cystic mass
• Inferior pole of the gland, adjacent and posterior to the angle of the mandible
• Histopathological features:
  
  • Numerous cystic spaces of irregular outline contain papillary projections lined by columnary eosinophilic cells (oncocytes)
  • Lining cells are supported by cuboidal cells that overlie lymphoid tissue with germinal centers
• Treatment : Surgical Excision