Growth Disorders 3

Question 1

What are some of the macroscopic morphological features of malignant neoplasms

Answer 1

Invasive
Sometimes circumscribed 
Sometimes capsule 
Necrosis 
Haemorrhagic 
Variegated

Question 2

What are some microscopic morphological features of benign neoplasms

Answer 2

Usually not pleomorphic
No abnormal mitoses
Low mitotic rate
No invasion/necrosis 
No desmoplasia
Low nuclear: cytoplasmic ratio
Well differentiated

Question 3

What are some microscopic morphological features of malignant neoplasms

Answer 3

Pleomorphism
Dark nuclei (hyperchromic)
High mitotic activity
Necrosis
Microscopic invasion
Vascular invasion
Reaction to invasion (desmoplasia)
High nuclear to cytoplasmic ratio
Well, moderate, poor or undifferentiated

Question 4

What type of biological behavior do malignant neoplasms have

Answer 4

Proliferation of transformed cells, invasion, distant spread (metastasis)

Question 5

What are some features of precancerous lesions

Answer 5

• Disordered growth, differentiation and maturation of cellular components of tissue.
• Confined to the epithelium (no invasion)
• Morphological expression of disturbance of growth regulation.
• individual dysplastic cells show features similar to malignant cells

Question 6

Discuss the progression of pre cancerous lesions to malignancy

Answer 6

Pre cancerous lesions first localized, often asymptomatic

• penetrate basement membranes
• movement through extra cellular matrix
• penetrate vascular channels (most cells don’t survive journey)
• exit to new tissue sites
• survival, growth as metastasis, evoking angiogenesis, growth factors secreted

Question 7

What type of cancer is lymphatic dissemination most common in

Answer 7

Carcinomas

Question 8

What type of cancers is haematogenous dissemination most common in and are veins or arteries more easily penetrated and why

Answer 8

Sarcomas

Veins more commonly penetrated as thinner walls than arteries

Question 9

What are some of the macroscopic morphological features of benign neoplasms

Answer 9

Capsule
Circumscribed
No invasion
Uniform, not usually haemorrhagic
Rarely necrotic