Neoplasia IV

Question 1

4 things a pathologist must find out about a cancer?

Answer 1

Can it be surgically removed?
What is it?
How far has it spread? - depends on type of tumour and anatomical site
How bad is it? How malignant is it behaving? - different to spread

Question 2

Normal histology?

Answer 2

Nature likes organisation, smooth edges, round things, symmetry and also uniformity (homogenous)

Most growing lesions stimulate a response by surrounding tissue and it is fenced off with a capsule (ENCAPSULATED) - forming a capsule takes time and indicates that the lesion is slow-growing (slow-growing lesions are usually benign)

Question 3

Malignant lesions characteristics?

Answer 3

Look bad
Do not look normal:
Pleomorphism - many shapes and sizes
Hyperchromasia - many different colours (some benign tumours can have this)
Mitoses - rapid proliferation/abnormal mitosis is disorganised in malignancy

Irregular
Infiltrative (edge is not smooth)
Destructive (grows in and destroys tissues)
Necrosis - in centre of tumour

Not encapsulated

Question 4

Heterogenous appearance?

Answer 4

Different areas due to, e.g: haemorrhage and necrosis (lack of blood supply to tumour)

Question 5

Histopathology of benign structures?

Answer 5

Nature likes organisation, etc

Regularity - nuclei look like each other and are the same colour

Question 6

What is the N:C ratio?

Answer 6

Nucleus : Cytoplasm ratio
Low ratio is a benign feature
High ratio is a feature of malignant tumours

Question 7

What is differentiation?

Answer 7

All cells originate from a stem cell and receive various signals to mature into a specific cell type with a specific function - cells differentiate/specialise

Well differentiate - cells appear as they should
Poorly differentiated - difficult to tell what the cell of origin is (can be characteristic of cancer)

Question 8

Taxonomy of tumours?

Answer 8

Big groups:
Epithelial
Mesenchymal - connective tissue
Haematopoietic - wbcs, etc
Others - melanocytic, brain (glial)

Question 9

Types of epithelial cancer?

Answer 9

Epithelium - carcinomas
Glandular - adenoma (benign) vs carcinoma (malignant)
Squamous - papilloma (finger-like) vs SCC (Squamous Cell Carcinoma)
Bladder - Transitional Cell Carcinoma (TCC), some times called urothelial cell carcinoma

Question 10

Benign and malignant name endings?

Answer 10

Benign -oma

Malignant -cinoma

Question 11

What is a mesenchyme?

Answer 11

Connective tissue, like bone, cartilage, peripheral nerves, fat, fibrous tissue, smooth muscle, skeletal muscle and others

Question 12

Malignant lesions of connective tissue are known as?

Answer 12

SARCOMAS

Question 13

Tumours of fat tissue?

Answer 13

Benign tumours are common - lipoma (usually subcutaneous)

Malignant - liposarcoma (rare, and tend to be in deep, soft tissue, retroperitoneal and testicular)

Question 14

Tumours of bone?

Answer 14

Benign - osteoma

Malignant - osteosarcoma. Rare and tend be in children with long bones

Question 15

Tumours of cartilage?

Answer 15

Benign - enchondroma (lots of)
Malignant - chondrosarcoma

“Chondro”

Question 16

Tumours of striated muscle?

Answer 16

Rhabdomyoma - rare and tend to be in children
Rhabdomyosarcoma - rare and tend to be in eye, bile duct, gynae tract and some other areas

“Rhabdo” - derived from “striated”

Question 17

Tumours of smooth muscle?

Answer 17

Benign - leiomyoma (one of the most common tumours in the body - common in uterus, etc)
Leimyosarcoma - very uncommon

Question 18

Tumours of nerves?

Answer 18

Benign - neurofibroma, schwannoma (benign tumour of schwann cells)
Malignant - malignant peripheral nerve sheath tumour

Question 19

Tumours of blood vessels?

Answer 19

Benign - haemangioma, etc
Malignant - angiosarcoma, Kaposi’s sarcoma (often seen in AIDs but is not caused by it; caused by an infection and is susceptible to Herpes virus)

Question 20

What is Ewing’s sarcoma?

Answer 20

Rare disease in which cancer cells are found in the bone or in soft tissue

Question 21

What is synovial sarcoma?

Answer 21

Rare form of cancer which usually occurs near to the joints of the arm, neck or leg. It is one of the soft tissue sarcomas

Question 22

What is a fibrosarcoma?

Answer 22

Sarcoma in which the predominant cell type is a malignant fibroblast.

Question 23

Tumours in CNS?

Answer 23

Gliomas - different group that range from benign version of a tumour to malignant version

Question 24

Meaning of melanocytic?

Answer 24

Freckle - ephelis
Mole - naevus
Malignant - melanoma (exception to benign ending with -oma)

Question 25

Blood tumours?

Answer 25

ALWAYS MALIGNANT as already systemic, e.g: leukaemias and lymphomas

Question 26

Staging?

Answer 26

TNM - Tumour Node Metastasis
Often depends on site

Stage does not equal progression:
Can have a well differentiated tumour that has grown slowly but has been there for a long time - will have a high stage
Could have an aggressive, rapidly-growing cancer that is caught early - will have a low stage

Question 27

Grading?

Answer 27

Give an indication of what cells are actually like
Can use concept of differentiation:
Well differentiated = low grade
Poorly differentiated = high grade

Question 28

What is needed to characterise a tumour?

Answer 28

Both stage and grade