Dysplasia

Dysplasia

  • A degree of failure of maturation of a tissue associated with a tendency to aneuploidy and pleomorphism but without the capacity to spread
  • An abnormality of development of tissue in which fibrous or other non-specialised tissue is present instead of the expected tissue

 

Causes of dysplasia

  1. Chemicals
    • Smoking
    • Alcohol (larynx, stomach)
  2. Viruses
    • HPV 16,18
  3. Specific chronic inflammation
    • UC
  4. Non-specific chronic inflammation
    • Cystitis leading to bladder carcinoma

 

Sites of Dysplasia

  1. Respiratory tract
    • Bronchus: in relation to smoking
  2. Gastrointestinal tract
    • Oesophagus - in relation to candidiasis or other chronic irritation with results in squamous dysplasia
    • Oesophagus: Barrett's oesophagus - glandular dysplasia
    • Stomach: H.pylori infection
    • Large bowel: ulcerative colitis
  3. Urogenital tract
    • Cervix: CIN

Histological featurs

  1. Multilayering (of a columnar or cuboidal) epithelium
  2. Mitotic figures - increased in number, presence of abnormal mitoses
  3. Pleomorphism
  4. Hyperchromatism
  5. Loss of cell-cell adhesion resulting in shedding
  6. No invasion of basement membrane