Head and Neck
Question 1. Classify salivary gland tumors.
Answer:
Salivary gland tumors
1. Benign
- Pleomorphic adenoma, War thin tumor, oncocytoma, basal cell adenoma, ductal papilloma
2. Malignant
- Mucoepidermoid carcinoma, adenocarcinoma not otherwise specified (NOS), acidic cell carcinoma, adenoid cystic carcinoma, malignant mixed tumor, squamous cell carcinomas
Question 2. Write a note on the adamantine of the jaw.
Answer:
Ameloblastoma/Adamantine of jaw
- The most common epithelial odontogenic tumors
- Age group: 3–5 decades
- Most common site: Mandible
- X-ray demonstrates a lytic expansive lesion
Gross
Read and Learn More Preparatory Manual of Pathology Question and Answers
- Solid and cystic
Microscopy
- Follicular and plexiform subtypes are the most common
- Follicular type: Follicles containing basaltic cells lining the basement membrane and the central portion of the follicle resembles stellate reticulum
- Plexiform type: Irregular masses and cords of epithelial cells within the stoma
Question 3. Write a note on the pleomorphic adenoma of a salivary gland.
Answer:
Pleomorphic adenoma (mixed tumors)
- Benign tumors that consist of a mixture of ductal (epithelial) and epithelial cells
- The most common site is the parotid gland
Risk factors
- Radiation exposure increases the risk
- Chromosomal rearrangements involving PLAG1
Morphology
Gross
- Presents as a rounded, encapsulated, well-demarcated masses
- Cut surface: Gray-white with myeloid-like areas
Microscopy
- Epithelial elements are arranged in acini, tubules, strands, or sheets of cells
- Epithelial cells in the ducts are surrounded by a epithelial cell layer in a background of myeloid substance
Question 4. Write a note on War thin’s tumor of a salivary gland.
Answer:
War thin tumor (papillary cystadenoma lymphomatous)
- Arises from the parotid gland
- Occurs more commonly in males
- Age group: Fifth to seventh decades of life
- 10% are multifocal and 10% are bilateral
- Smokers are at increased risk of developing these tumors
Gross
- Round encapsulated mass
- Cut surface: It shows multiple cystic spaces containing serous or mutinous secretions
Microscopy
- Cystic spaces are lined by a double layer of neoplastic epithelial cells resting on a dense lymphoid stoma with prominent germinal centers
- Cystic space lumen often contains secretions
Question 5. Write a note on malignant salivary gland tumors.
Answer:
Mucoepidermoid carcinomas
- The most common primary malignant tumor of the salivary glands
- Most common site: Parotid gland followed by minor salivary glands
Morphology
Gross
- Circumscribed tumor, but lack well-defined capsule
- Cut surface—solid with small, much-containing cysts
Microscopy
- The tumor grows in nests, sheets, and cords
- Tumor cells are composed of mixtures of squamous cells, mucus-secreting cells, and intermediate cells
Adenoid Cystic Carcinoma
- The most common site—the minor salivary glands (palate)
- Can show perineal invasion
Gross
- Small, poorly encapsulated, infiltrated lesions
Microscopy
- Tumor cells are arranged in a cribriform pattern
- Tumor cells have dark, compact nuclei and scant cytoplasm
- Cribriform spaces are filled with hyaline material
Question 6. Write a short note on nasopharyngeal carcinoma.
Answer:
Nasopharyngeal carcinoma
- Bimodal age group (15–25 years and 60–69 years)
- Etiopathogenesis: ABV infection, diets rich in nitrosamines, and smoking
- ABV detection is done by: PCR or by FISH (which detects Re-encoded RNA, EBER-1, or proteins such as LMP-1 in malignant epithelial cells)
Three patterns
- Keratinizing squamous cell carcinomas
- Non-keratinizing squamous cell carcinomas
- Undifferentiated carcinomas (lymphoepithelioma)
Treatment
- Radiotherapy is the standard modality of treatment
- Undifferentiated carcinoma is the most radio-sensitive
- Keratinizing squamous cell carcinoma is the least radio-sensitive
Question 7. Write a note on paragangliomas.
Answer:
Paragangliomas
- Arises from the clusters of neuroendocrine cells
- In adrenal glands, they are termed pheochromocytoma
- 70% of extra-adrenal paragangliomas occur in the head and neck region
Paragangliomas can develop at:
- Paravertebral paraganglia (example organs of Zuckerkandl)—innervated by the sympathetic nervous system and are chromatin-positive
- Paraganglia related to the great vessels of the head and neck (aorticopulmonary chain): For example, carotid bodies (most common); aortic bodies; jugulate ganglia—innervated by the parasympathetic nervous system
Carotid body tumor
- Arises at the bifurcation of the common carotid artery
- Slow-growing and painless masses
- Age group: 40–50 years
- Familial cases are associated with MEN-2 syndrome
Morphology
Microscopy
- Composed of nests (Zellballen) of round to oval chief cells, surrounded by delicate vascular septal
- Chief cells stain strongly for chromogenic, synaptophysin, neuron-specific enolate
- Surrounding the chief cells there occur spindle-shaped stromal cells (sustentacular cells), which are positive for S-100 protein
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