Hairy leukoplakia
Post on 14-Jan-2016
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Hairy leukoplakia
• Distinctive oral lesion• Seen in immunocompromised patients• 80% of patients with hairy leukoplakia have
HIV infection
Hairy leukoplakia
• Takes the form of– White or black – Confluent– Patches of Fluffy (hairy)– Hyperkeratotic thickenings– Almost always on the lateral border of the tongue
Hairy Leukoplakia
Squamous Cell Carcinoma
• Oral Cavity
Squamous Cell Carcinoma
• 95% of cancers of Head and Neck are Squamous Cell Carcinomas arising most commonly in the oral cavity
• Head and Neck Squamous Cell Carcinoma - HNSCC
• HNSCC is the 6th most common cancer in the world today
• Long term survival is 50%
Squamous Cell Carcinoma
• Long term survival is only 50% because– Oral cancer is diagnosed in advanced state– Frequent development of multiple primary
tumours
Squamous Cell Carcinoma– Pathogenesis
• Multifactorial
• North America and Europe -
– Middle aged men
– Chronic abusers of smoked tobacco
– Family history
– HPV infection
– Actinic radiation - Sunlight (lower lip)
Squamous Cell Carcinoma
– Pathogenesis
• Multifactorial
• Outside of North America and Europe -
– Chewing of betel quid - Paan in India
– Betel quid contains
»Areca nut, Slaked lime, Tobacco wrapped in betel leaf
Squamous Cell Carcinoma
• Molecular biology– Development of squamous cell carcinoma a
multistep process involving a sequential activation of oncogenes and inactivation of tumour suppressor genes in a clonal population of cells.
Squamous Cell Carcinoma
• Molecular biology– Loss of chromosomal regions 3p and 9p21 -
inactivation of p16 which is a suppressor of cyclin dependent kinase
– Loss of chromosome 17p with mutation of p53 tumour suppressor gene
– Deletions of 4q, 6p, 8p 11q, 13q, and 14q
Squamous Cell Carcinoma
• Morphology– May arise anywhere in the oral cavity• Ventral surface of tongue, floor of mouth, lower lip, soft
palate and gingiva
– Preceded by premalignant lesions
Squamous Cell Carcinoma
• Morphology
– Early stages
• Raised firm, pearly plaques
• Irregular roughened or verrucous thickening
– Later
• Ulcerated, protruding masses
• Irregular, firm, and indurated (rolled) borders
Squamous Cell Carcinoma• Morphology - Histology
– Begin as dysplastic lesions
– May or may not progress to full thickness dysplasia prior to invasion
– Patterns range from
• Well differentiated keratinizing
• Anaplastic,
• Sarcomatoid
– Degree of keratinization does not correlate with behaviour
Squamous Cell Carcinoma
• Morphology - Histology
– Tend to infiltrate locally before metastasizing
– Routes of extension depends on primary site
– Favored sites of metastasis
• Cervical lymph nodes (local metastasis)
• Mediastinal lymph nodes (distant metastasis), lungs, liver and bones. (often occult)
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