Introduction to Benign and Malignant Disease

Question 1

What is the size of the cell population determined by?

Answer 1

• Rates of cell proliferation
• differentiation
• death by apoptosis

Question 2

What is an example of a terminally differentiated cell (not capable of replication)?

Answer 2

Monocytes

Question 3

What is Apoptosis?

Answer 3

Apoptosis- Programmed cell death

Question 4

What are Disorders of growth and Neoplasia (uncontrolled growth of cells)?

Answer 4

• Hypertrophy
• Hyperplasia
• Atrophy
• Hypoplasia
• Metaplasia
• Dysplasia
• Neoplasia

Question 5

What is Hypertrophy?

Answer 5

Hypertrophy - An increase in cell size

Question 6

What is Hyperplasia?

Answer 6

Hyperplasia - An increase in cell number

• Enlargement of gingival tissues
• Hyperplastic responses within epithelium and underlying connective tissue
• various causes including drugs

Question 7

What is Atrophy?

Answer 7

Atrophy - Reduction in cell size by loss of cell substance

Causes e.g. ageing, lack of use/stimulation

Question 8

What is Hypoplasia?

Answer 8

Hypoplasia - Reduced size of an organ that never fully developed to normal size

A developmental defect

Question 9

What is Metaplasia?

Answer 9

Metaplasia - Reversible change in which one adult cell type is replaced by another adult cell type

Can be part of an adaptive response to stress

Reprogramming of stem cells

E.g. Bronchus

Question 10

What is the only growth change that is not reversible?

Answer 10

Hypoplasia

Question 11

What does Dysplasia mean?

Answer 11

Abnormal growth

Is a broad term and can be used to describe different types of abnormal growth such as Epithelial dysplasia,

Question 12

What are the different degrees of dysplasia?

Answer 12

Mild

Moderate

Severe (carcunoma in situ)

The more severe forms have a more significant risk of progressing to invasive malignancy

Question 13

What is Neoplasia?

Answer 13

A neoplasm is an abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues, and persists in the same excessive manner after cessation of the stimuli that evoked the change

i.e. uncontrolled growth of cells that is not under physiologic control

Question 14

Why do tumour cells clone expand?

Answer 14

Tumour cells lack the normal control mechanisms thus the clone expands due to uncontrolled proliferation

Question 15

What are the 2 classifications of tumours?

Answer 15

• Behaviour
• Histogenesis

Question 16

What the 2 types of behaviour?

Answer 16

1. Benign
2. Malignant

Question 17

What are Benign Tumours

Answer 17

Growth pattern - Expand and remain localised. Well circumscribed. Encapsulated.

Growth Rate - Slower

Clinical Effects - Local pressure effects; hormone secretions

Treatment - Local excision

Nuclei - Small, regular, uniform

Mitoses - Few, normal

Question 18

What are Malignant Tumours?

Answer 18

Growth pattern - Infiltrate locally, metastasize (spread to different sites)

Growth Rate - Faster

Clinical effects - local pressure and destruction, Inappropriate hormone secretion, Distant metastases

Treatment - Excision +/- additional therapy

Nuclei - Larger, pleomorphic

Mitoses - Increased, often numerous, abnormal forms

Question 19

Histogenetic Classification of Tumours means what?

Answer 19

Tumours can be further classified according to the cell type they resemble, ie their differentiation.

Most tumours resemble to some extent the tissue from which they arise.

Question 20

If the Tissue origin is Covering epithelia or Grandular epithelia what are the names of the benign and malignant equivilant?

Answer 20

Covering epithelia

• Benign - Papilloma*
• Malignant - Carcinoma*

Glandular epithelia

• Benign - Adenoma*
• Malignant - Adenocarcinoma*

Question 21

What will affect Cancer Prognosis?

Answer 21

• Tumour type
• Tumour grade
• Tumour stage
• Patient

Question 22

Why is it important to know the tumour type?

Answer 22

Every tumour behaves differently.

Anatomical knowledge is also important such as lymphatic drainage

Question 23

What are the tumour grades?

Answer 23

1. Well differentiated
2. Moderatelt differentiated
3. Poorly differentiated