Tissue Growth Disorders and Dysplasia

Question 1

What are the 2 types of Physiological Hyperplasia? Give examples

What are some examples of Pathological Hyperplasia?

What is an example of Hypoplasia?

What are some examples of Physiological Hypertrophy?

What is an example of Pathological Hypertrophy?

What are some examples of Physiological Atrophy?

What are some examples of Pathological Atrophy?

Answer 1

• • Hormonal hyperplasia e.g. Increase in breast glandular epithelium during Puberty/Pregnancy
  • Compensatory hyperplasia - Need to increase cells after damage or resection e.g. Liver regrowth after donation of a lobe
• Prostatic hyperplasia, Endometrial hyperplasia, Thyroid hyperplasia
• Pulmonary hypoplasia due to Oligohydramnios
• Skeletal muscle after regular exercise, Myometrium during pregnancy
• LV Hypertrophy in HTN
• Thymus atrophy after puberty, Uterus after delivery
• Disuse (Bed rest), Denervation (Spinal cord injury), Pressure

Question 2

What is Agenesis?

What is Aplasia?

What is Atresia?

What is Heterotopia?

What is Hamartoma?

What is Metaplasia?
→ What’s an example of Squamous metaplasia?
→ What’s an example of Intestinal metaplasia?
→ What’s an example of Connective tissue metaplasia?

Answer 2

• Complete absence of an organ
• Failure of development of an organ
• Absence of an Opening
• Well-developed tissue at the wrong site
• Mass of mature, disorganised tissue at an appropriate site
• Replacement of one mature cell type with another
  → Columnar to Squamous in Respiratory tract of Smokers
  → Squamous to Columnar in Barrett’s Oesophagus (Acid reflux)
  → Cartilage/Bone/Adipose tissue in abnormal areas (Myositis Ossificans)

Question 3

Premalignancy and Predisposition to Malignancy:
What is a Premalignancy? Give an example

What is a Dysplasia? What is it characterised by?
→ What’s it called when it extends the full thickness of the epithelium without an breaching of the basement membrane?

What are the Cytological features of malignancy?

How can Dysplasia be used when screening for Cervical cancer?

Answer 3

• Local alterations in tissues that increase the risk of cancer at that site e.g. Cirrhosis increasing the risk of Hepatocellular carcinoma
• Premalignant condition - Characterised by Disorganised epithelial cell growth
  → Carcinoma In Situ
• • Nuclear Pleomorphism and Hyperchromatism
  • ↑Nuclear : Cytoplasm ratio
  • Increased and Abnormal Mitoses visible
• HPV increases the risk of Cervical cancer, so if detected, cervical cells are checked for Dysplasia