Cellular pathology of Cancer

Question 1

Define Metaplasia.

Answer 1

A reversible change in which one adult cell type (usually epithelial) is replaced by another adult cell type

Question 2

Give two examples of metaplasia, one pathological and one physiological.

Answer 2

Barrett’s Oesophagus – gastro-oesophageal reflux can change the stratified squamous epithelium of the distal oesophagus to simple columnar

Cervix during pregnancy – the cervix opens up and the columnar epithelium of the endocervical canal is exposed to the acidic uterine fluids making it squamous

Question 3

What are the two types of metaplasia that can take place in Barrett’s Oesophagus?

Answer 3

Gastric metaplasia – stratified squamous to simple columnar

Intestinal metaplasia – goblet cells begin to appear

Question 4

State some features of cancer that are seen in dysplasia.

Answer 4

Large nuclei (and hyperchromatic) 
Increased mitoses 
Abnormal mitoses 
Increased nucleo-cytoplasmic ratio
Loss of architectural orientation 
Loss of uniformity of individual cells

Question 5

What is the difference between low and high-grade dysplasia?

Answer 5

They both show changes of dysplasia but the changes are more severe in high-grade dysplasia

High-grade has a high risk of progression to cancer

Question 6

What are the main features of benign tumours that separate them from malignant tumours?

Answer 6

They do not metastasise 
They do not invade 
They also are usually encapsulated (except for fibroids in the uterus)
Slow growing
Have normal mitoses

Question 7

Under what conditions can benign tumours be dangerous?

Answer 7

If they are in a dangerous location 
If they secrete something dangerous 
If they get infected 
If they bleed 
If they rupture 
If they become twisted

Question 8

What are the features of malignant tumours?

Answer 8

Invade surrounding tissues 
Spread to distant sites 
They also have no capsule 
Can be well or poorly differentiated 
Rapidly growing
Have abnormal mitoses

Question 9

Define metastasis.

Answer 9

A discontinuous growing colony of tumour cells, at some distance from the primary cancer

(Plural: Metastases)

Question 10

What are the two different types of benign epithelial tumour?

Answer 10

Papilloma – of the surface epithelium

Adenoma – of glandular epithelium

Question 11

Define carcinoma.

Answer 11

Malignant tumour derived from the epithelium

Question 12

What are the different types of carcinoma?

Answer 12

Basal cell carcinoma
Squamous cell carcinoma
Transitional cell carcinoma (transitional epithelium is found in the bladder)
Adenocarcinoma

Question 13

State some different types of benign soft tissue tumour.

Answer 13

Osteoma –bone
Lipoma - fat
Leiomyoma – smooth muscle

Question 14

Define sarcoma.

Answer 14

Malignant tumour derived from connective tissue (mesenchymal) cells

Question 15

What are the names given to malignant tumours of striated muscle, smooth muscle and the nerve sheath?

Answer 15

Striated muscle – rhabdomyosarcoma
Smooth muscle – leiomyosarcoma
Nerve sheath – Malignant peripheral nerve sheath tumour

Question 16

Define leukaemia.

Answer 16

Malignant tumour of bone marrow derived cells, which circulate in the blood

Question 17

Define lymphoma.

Answer 17

Malignant tumour of lymphocytes (usually) in lymph nodes (or other lymph tissues - e.g MALT?)

Question 18

Define teratoma.

Answer 18

A tumour derived from germ cells, which has the potential to develop into tumours of all three germ layers

Question 19

What is an important difference between teratomas in men compared to women?

Answer 19

Gonadal teratomas in men are almost always malignant

Gonadal teratomas in women are almost always benign

Question 20

Define hamartoma.

Answer 20

Localised overgrowth of cells and tissue native to the organ

In other words, the cells and tissues present are appropriate for that particular location but their structural organisation is inappropriate

Question 21

Which group of the population is hamartoma common in?

Answer 21

It is common in children and the hamartoma usually stops growing when the children stop growing

Question 22

What is the difference between grading and staging?

Answer 22

Grading – how well differentiated the cancer is
Staging – how far the cancer has spread

Staging > Grading in terms of prognosis

Question 23

What is meant by the ‘degree of differentiation’?

Answer 23

How much the tumour cells resemble the cells from which they are derived

Question 24

What are the grading systems for breast and prostate cancer?

Answer 24

Breast –Nottingham scoring system

Prostate – Gleason classification

Question 25

What is the term given to tumours that show little or no differentiation?

Answer 25

Anaplastic - VERY poor prognosis, hard to tell what kind of cancer it is sometimes as they are so poorly differentiated.