Salivary Gland Tumors

Question 1

What is the most common benign salivary gland tumor?

Answer 1

Pleomorphic adenoma.

Question 2

What are the components of pleomorphic adenoma?

Answer 2

Epithelial, myoepithelial, and stromal (myxoid, chondroid, or myxochondroid).

Question 3

Which gland is most commonly affected by pleomorphic adenoma?

Answer 3

Parotid gland (~80%).

Question 4

What is a key histopathologic feature of pleomorphic adenoma?

Answer 4

Mixed epithelial and mesenchymal components.

Question 5

What is the typical age range for pleomorphic adenoma presentation?

Answer 5

4th–6th decades.

Question 6

What are pseudopodia in pleomorphic adenoma?

Answer 6

Extensions from partially encapsulated tumors into surrounding tissue.

Question 7

What is metaplasia?

Answer 7

Replacement of one mature cell type by another as a response to chronic irritation.

Question 8

What are common types of metaplasia in pleomorphic adenoma?

Answer 8

Adipose, osseous, squamous, sebaceous, mucinous.

Question 9

What is metastasizing pleomorphic adenoma?

Answer 9

Benign pleomorphic adenoma with metastatic deposits, especially in bone, lung, and lymph nodes.

Question 10

What is carcinoma ex pleomorphic adenoma?

Answer 10

Malignancy arising from epithelial components of a preexisting pleomorphic adenoma.

Question 11

What are signs of carcinoma ex pleomorphic adenoma?

Answer 11

Capsular invasion, perineural invasion, cellular atypia.

Question 12

What is carcinosarcoma in salivary glands?

Answer 12

True malignant mixed tumor with both carcinomatous and sarcomatous components.

Question 13

What is Warthin tumor also known as?

Answer 13

Papillary cystadenoma lymphomatosum.

Question 14

Which salivary gland is Warthin tumor most commonly found in?

Answer 14

Parotid gland.

Question 15

What is Warthin tumor associated with?

Answer 15

Smoking; more common in males.

Question 16

What is the histology of Warthin tumor?

Answer 16

Papillary cystic structures lined by bilayered oncocytic cells, surrounded by lymphoid stroma.

Question 17

What is an oncocytoma?

Answer 17

Rare benign salivary gland tumor with eosinophilic granular oncocytes.

Question 18

What is a common risk factor for oncocytoma?

Answer 18

History of radiation exposure (20%).

Question 19

What is the most common malignant salivary gland tumor?

Answer 19

Mucoepidermoid carcinoma (MEC).

Question 20

What is the most common salivary gland tumor in children?

Answer 20

Mucoepidermoid carcinoma.

Question 21

What are the main cell types in MEC?

Answer 21

Mucous, epidermoid, and intermediate cells.

Question 22

What grading system is used for MEC?

Answer 22

Modified Hailey system: low, intermediate, high grade.

Question 23

What characterizes low-grade MEC?

Answer 23

Prominent cysts, mucous cells > epidermoid cells, well differentiated.

Question 24

What characterizes high-grade MEC?

Answer 24

Solid nests, epidermoid cells > mucous cells, dysplastic features.

Question 25

What is adenoid cystic carcinoma known for?

Answer 25

Perineural invasion and late metastasis.

Question 26

What are the three histologic patterns of adenoid cystic carcinoma?

Answer 26

Cribriform, tubular, solid.

Question 27

Which pattern of adenoid cystic carcinoma has the worst prognosis?

Answer 27

Solid pattern.

Question 28

Which pattern of adenoid cystic carcinoma has the best prognosis?

Answer 28

Tubular pattern.

Question 29

What is the most common histologic pattern in adenoid cystic carcinoma?

Answer 29

Cribriform ("Swiss cheese" appearance).

Question 30

What cells are found in adenoid cystic carcinoma?

Answer 30

Basaloid and myoepithelial cells.

Question 31

What is a common symptom of adenoid cystic carcinoma?

Answer 31

Pain due to nerve invasion.

Question 32

Where is adenoid cystic carcinoma commonly found?

Answer 32

Parotid, submandibular glands; minor glands in palate, tongue, lip.

Question 33

What is the cell of origin for acinic cell carcinoma?

Answer 33

Serous acinar cells.

Question 34

What is a histologic feature of acinic cell carcinoma?

Answer 34

Basophilic granular cytoplasm due to zymogen granules.

Question 35

What is the appearance of acinic cell carcinoma on histology?

Answer 35

Solid sheets with numerous small cysts.

Question 36

Which tumor shows squamous metaplasia with keratinization?

Answer 36

Pleomorphic adenoma.

Question 37

Which tumor most frequently shows perineural invasion?

Answer 37

Adenoid cystic carcinoma.

Question 38

What histologic feature is associated with pleomorphic adenoma?

Answer 38

Myxochondroid stroma.

Question 39

What is the most common minor salivary gland site for pleomorphic adenoma?

Answer 39

Palate.

Question 40

What should be done when metastasizing pleomorphic adenoma is suspected?

Answer 40

Full body survey.