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, NO goblet cells
Intestinal metaplasia – goblet cells begin to appear as well as columnar epithelium

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

(some of the histological features of malignancy are present)

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
High grade, darker nuclei

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 LEIOMYOMAS e.g fibroids in the uterus), 
Slow growing 
Normal mitoses

Question 7

Under what conditions can benign tumours be dangerous?

Answer 7

If they are in a dangerous location, e.g pituitary
If they secrete something dangerous , e.g insulinoma
If they get infected , e.g bladder infection from obstruction of ureter
If they bleed, e.g stomach
If they rupture e.g liver adenoma
If they become twisted (TORTS),e.g ovarian cyst can twist and cut off own blood supply

Question 8

What are the features of malignant tumours?

Answer 8

Invade surrounding tissues  
Metastasize
They also have no capsule (not always), 
Well or poorly differentiated (usually poorly), 
Rapidly growing 
Abnormal mitoses

Question 9

Define metastasis.

Answer 9

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

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 peripheral blood

Question 17

Define lymphoma.

Answer 17

Malignant tumour of lymphocytes (usually) in lymph nodes

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 in the TNM staging system?

Answer 22

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

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

Question 26

Give example of where dysplasia is commonly seen?

Answer 26

Cervix, HPV
Colon, Ulcerative Colitis
Stomach, P. anaemia

Question 27

Give an example of a teratoma

Answer 27

Dermoid cysts

Question 28

Give an example of a hamartoma

Answer 28

Bile duct hamartoma

Question 29

Define neoplasia

Answer 29

An abnormal autonomous proliferation of cells that is unresponsive to normal growth control mechanisms.

Question 30

Define dysplasia

Answer 30

the presence of cells of an abnormal type within a tissue, which may signify a stage preceding the development of cancer