Neoplasia

Question 1

Define tumour

Answer 1

Swelling

Question 2

Define neoplasm

Answer 2

Abnormal growth of cells which persists after the initiating stimulus has been removed (opposite of hyperplasia).

Caused by cell growth which is not under control of normal regulatory mechanisms

Question 3

Benign neoplasm

Answer 3

Cells grow as a compact mass and remain at their site of origin

Question 4

Malignant neoplasm

Answer 4

Arise when growth of cells is uncontrolled. Cells spread into the surrounding tissue and can spread to distant sites via the blood.

Question 5

Define cancer

Answer 5

A malignant growth

Question 6

Name 4 benign connective tissue neoplasms

Answer 6

Smooth muscle: Leiomyoma
Fibrous tissue: Fibroma
Bone: Osteoma
Cartilage: Chondroma
Fat: Lipoma
Nerve: Neurofibroma

Question 7

Sarcoma

Answer 7

Malignant connective tissue neoplasm

Question 8

Papilloma

Answer 8

Benign epithelial neoplasm of squamous and transitional epithelium

Question 9

Adenoma

Answer 9

Glandular epithelium

Question 10

Carcinoma

Answer 10

Malignant epithelial neoplasms

e.g. Skin: squamous cell carcinoma. Bowel: adenocarcinoma

Question 11

State three differences in the behaviour of benign and malignant tumors

Answer 11

Benign: 
No invasion
No metastasis
Retain function
Variable growth rate, often low 

Malignant: 
Invade
Metastasise
Lose function
Variable growth rate, may be high

Question 12

Name two macroscopic differences between benign and malignant tumours

Answer 12

Benign:
Capsule
Well defined edge

Malignant:
Ill-defined margin
Haemorrhage
Necrosis

Question 13

Name two microscopic differences that are seen in benign and malignant tumours

Answer 13

Benign: 
Nuclear variation in size,    chromasia and shape minimal
Low mitotic count, normal mitoses
Retention of specialisation 
Structural differentiation retained
Organised
Expansile cohesive growth

Malignant:
Nuclear variation in size, chromasia and shape minimal to marked, often variable
Low to high mitotic count, abnormal mitoses
Loss of specialization
Structural differentiation shows wide range of changes
Not organised
Local invasion beyond normal boundaries

Question 14

What are the essential alterations required for malignancy?

Answer 14

Self Sufficiency in the absence of Growth Signals
Insensitivity to Negative Growth Signals
Defects in DNA Repair
Evasion of Apoptosis
Limitless Replicative Potential
Sustained Angiogenesis
Ability to Invade and Metastasise

Question 15

Dysplasia

Answer 15

Premalignant condition with increased cell growth, cellular atypia and altered differentiation

Question 16

In-situ malignancy

Answer 16

Epithelial neoplasm with features of malignancy:
altered cell growth, cytological atypia, altered differentiation

but no invasion through basement membrane