Oral Cavity: Head and Neck Pathology

Oral Cavity

• Caries, gingivitis, and periodontitis are oral diseases that can be characterized and defined.
• Oral inflammatory and reactive lesions include:
  • Aphthous ulcers
  • Irritation fibromas
  • Peripheral ossifying fibromas
  • Pyogenic granulomas
  • Peripheral giant cell granulomas
• These lesions have distinct etiopathogenesis, morphology, and clinical significance.
• Oral herpes simplex infection and oral candidiasis (thrush) are two common oral infections that can be described in terms of risk factors, morphologic changes, and clinical features.
• Oral manifestations of systemic diseases include:
  • Infectious diseases
  • Dermatologic conditions
  • Hematologic disorders
• Hairy leukoplakia is a brief characteristic of oral manifestations of systemic diseases.

Leukoplakia and Erythroplakia

• Leukoplakia and erythroplakia are two terms that can be defined and characterized.
• Morphologic features of leukoplakia include:
  • White patches or plaques on the oral mucosa
  • Cannot be rubbed off or removed
• Clinical significance of leukoplakia includes:
  • Potential to develop into oral squamous cell carcinoma (SCC)
  • Requires regular monitoring and biopsy
• Erythroplakia is a red, velvety patch on the oral mucosa that cannot be rubbed off or removed.

Oral Squamous Cell Carcinoma (SCC)

• Oral SCC is a type of cancer that can be described in terms of etiopathogenesis, morphology, and clinical consequences.
• Morphologic features of oral SCC include:
  • Invasion of tumor cells into the surrounding tissue
  • Differentiation of tumor cells into keratin-producing cells
• Clinical consequences of oral SCC include:
  • Local invasion and destruction of tissue
  • Metastasis to lymph nodes and distant organs
• Differences between HPV-associated and non-associated SCC include:
  • HPV-associated SCC is more common in younger patients and has a better prognosis
  • Non-associated SCC is more common in older patients and has a poorer prognosis

Odontogenic Cysts and Tumors

• Odontogenic cysts and tumors include:
  • Inflammatory odontogenic cysts (e.g. dentigerous cyst, radicular cyst)
  • Developmental odontogenic cysts (e.g. keratocystic odontogenic tumor)
  • Tumors of odontogenic epithelium (e.g. odontomas, ameloblastomas)
  • Tumors of odontogenic mesenchyme (e.g. odontogenic fibroma)
  • Tumors of odontogenic epithelium and mesenchyme (e.g. odontogenic myxoma)
• Odontomas are benign tumors that arise from the dental pulp and can be characterized.
• Ameloblastomas are benign tumors that arise from the enamel organ and can be characterized.

Nose and Nasopharynx

• Inflammatory lesions of the nose and nasopharynx include:
  • Infectious rhinitis (common cold)
  • Allergic rhinitis (hay fever)
  • Chronic rhinitis
  • Nasal polyps
  • Sinusitis
  • Pharyngitis
  • Tonsillitis
• Infectious rhinitis is caused by viruses and can evoke a profuse catarrhal discharge.
• Allergic rhinitis is initiated by hypersensitivity reactions to allergens and can cause marked mucosal edema, redness, and mucus secretion.
• Chronic rhinitis is a sequel to repeated attacks of acute rhinitis, with the eventual development of superimposed bacterial infection.

Salivary Gland Neoplasms

• Salivary gland neoplasms can be classified into benign and malignant tumors.
• Benign salivary gland neoplasms include:
  • Pleomorphic adenoma (mixed tumor)
  • Warthin tumor
  • Oncocytoma
  • Other adenomas
• Malignant salivary gland neoplasms include:
  • Mucoepidermoid carcinoma
  • Adenocarcinoma (NOS)
  • Acinic cell carcinoma
  • Adenoid cystic carcinoma
  • Malignant mixed tumor
  • Squamous cell carcinoma
• Pleomorphic adenoma is a benign tumor that consists of a mixture of ductal and myoepithelial cells, and can be characterized.
• Warthin tumor is a benign tumor that arises almost exclusively in the parotid gland, and can be characterized.
• Adenoid cystic carcinoma is a malignant tumor that affects mostly minor salivary glands, and can be characterized.