Oral Squamous Cell Carcinoma

Oral Squamous Cell Carcinoma

• Defined as a malignant neoplasm occuring in the oral cavity its important to noe that lip cancers, oral cavity cancers and oropharyngeal cancers are anatomically different subsets

Etiology and Pathophysiology

• Cancer arises by progressive accumulation of genetic damage
• about 6 - 8 gene mutations are typical with each confering a grwoth advantage on the cell

Contributory factors :

Risk factors include:

• tobacco (smoked and smokeless)
• Alcohol
• betel quid/ areca nut
• Sunlight (for lip OSCC)
• HPV plays a minor role in OSCC of the oral cavity
  • Major in role in the oropharynx
• Idiopathic
  • A minor of patients appear to have no risk factors. Most are elderly and female
• Increasing age
  • most cases occur after the age of 50
  • but the meidan age is decreasing overall
• Socioeconomic factors
  • indivudals the below factors have a greater resk of devleoping oral cnacer independent of lifestyle habits such as tobacco and alcohol consumption
    • lower occupational status
    • lower educational levels
    • lower incomes
    • manual labor roles

Prevalence

More than 90% of malignant neoplasms in the mouth are squamous cell carcinomas

• Highest ASR is in the Southeast asia region wiht the second highes in Europe
• collectively seen in lower socioecnomic groups

Histological Features

• Dysplastic stratified squamous epithelium that extends through the basement membrane and into the underlying fibrous connective tissue without attachement to the surface
• Malignant epithelial cells show eosinophillic cytoplasm, hyperchromatic nuclei, pleomorphism, mitotic activity, individual cell keratinization and intercellular bridging
• Superficial or microinvasion can be used to describe the earliest moment of invasion
• Malignant epithelium can invade fibrous connective tissue in islands, cords or individual cells
• Keratin pearls of round eosinohillic, concentric layers of keratin can be seen and are associated with well differentiated tumours
• 3 histological grades for convnetions squamous cell carcinoma include we,, moderatly and poorly differentiated based on amount of keratinization, mitotic activity, cellular and nuclear pleomorphism, pattern of invasion and host response

Clinical Features

Location

• Posterolateral tongue is the most common site of primary disease
• Floor of the mouth is the next most common site
• Anterior tongue is most common in North America and Europe
• can also be seen in gingiva, palate and buccal mucosa

For oropharyngeal carcinoma :

• in two thirds of cases its located in the tonsil

Appearance

**REd Flag Features **:

• Oral ulcers that have lasted for more than 2 weeks
• Oral ulcers that recur
• nontraumatic oral ulcers in children
• pigmented lesions on the oral mucosa

can present as:

• red, white or mixeed lesion of the oral mucosa of unknown origin or with features of potentially malignan disease such as
  • induration
  • ulceration iwth rolled margins
  • fixation to underlying tissues
  • Exophytic
• Facial or oral paresthesia
• Fixation: the lesion is attached to underlying structures

Differential Diagnoses

• Traumatic ulcers
• Kaposi Sarcoma
• Benign epithelial pathosis
  • Leukoplakia
  • Erythorplakia
• Syphillis (secondary and tertiary stages )
• Chronic hyperplastic candidosis
• Carcinoma of the gingiva can mimic inflammotry conditions like gingivitis

Relevant Clinical Investigations

• Mri with CT or PET scan
• Chest X- ray
• TNM staging
• Biopsy
• Blood tests
  • Serological testing for onccytic disease
  • Hematinics (undertaken for ulceration)
    • IRON
    • Folate
    • B12
    • Ferritin

Patient Management

• Surgery:
  • Tumor resection with clear margins
  • Radiation therapy (adjuvant or definity)
  • Chemotherapy (combined with radiation)
• Regular monitoring :
  • Every 2 months for the first 2 years
  • Every 6 months for years 3 to 5
  • Once a year after 5 years