Tumour pathology 2

Question 1

Properties of cancer cells

Answer 1

• Loss of tumour suppressor genes
• Gain of function of oncogenes
• altered cellular function
• abnormal morphology
• cells capable of independent growth
• BUT no single feature is unique to cancer cells
• tumour biomarkers

Question 2

Tumour suppressor genes?

Answer 2

‘suppress tumour development’ normally act to inhibit cell proliferation and prevent tumor development
switched off in tumours

Question 3

What is an oncogene? Gain of function of oncogenes?

Answer 3

a gene which in certain circumstances can transform a cell into a tumour cell. Expressed (turned on) transform into tumour e.g
B-raf
Cyclin D1 etc

Question 4

‘Loss of cellular function’ expand

Answer 4

loss of cell-to-cell adhesion- cells don’t stick together
altered cell-to-matrix adhesion- cells don’t stick to underlying connective tissue (matrix)
production of tumour-related proteins- tumour biomarkers

Question 5

Tumour biomarkers?

Answer 5

substance or process that is indicative of the presence of cancer in the body
may be produced by the cancer tissue itself or by other cells in the body in response to cancer
groups of proteins, maybe genes
-many different potential markers of cancer development and progression
can be used diagnostically/therapeutically

Question 6

Clinical utility of tumour biomarkers

Answer 6

screening
diagnosis
prognostic- identifying patients with a specific outcome
predictive- identifying patients with tumour with specific properties that would benefit from administration of specific drug/therapy

Question 7

Clinical use of oestrogen receptor?

Answer 7

Breast cancer

Question 8

Clinical use of Carcino-embryonic antigen (CEA)?

Answer 8

CEA is a blood test used to help diagnose and manage certain types of cancers. The CEA test is used especially for cancers of the large intestine and rectum.
i.e Colorectal cancer

Question 9

What is the BRAF biomarker? and which cancer is it useful for detecting/managing?

Answer 9

BRAF is a gene (oncogene)
many mutations of the BRAF gene have been found at a high frequency in specific cancers
testing for BRAF mutations is useful for Melanoma detection and management

Question 10

What is tumour growth a balance between?

Answer 10

is balance between cell growth (angiogenesis) and cell death (apoptosis)

Question 11

Tumour angiogenesis

Answer 11

New blood vessel formation by tumours
required to sustain tumour growth- the more blood vessels in and around the tumour means the worse the cancer outcome as there is more chance of it spreading by breaking off and moving into circulation
provides route for release of tumour cells into circulation

Question 12

Apoptosis

Answer 12

Programmed single cell death
active cell process
regulates tumour growth- have apoptosis as cancer doesn’t take over whole body- it’s a balance
over proliferation- results in cancer
involved in response to chemo or radiotherapy

Question 13

Why is the spread of cancer significant clinically?

Answer 13

prognosis depends on extent of cancer spread

if metastatic tumours form this is a major clinical problem

Question 14

What is the simple 3 step process of tumour spread?

Answer 14

normal
tumour
metastasis

in reality- not this linear

Question 15

What are some modes of spread of cancer

Answer 15

local spread
lymphatic spread
blood spread
trans-coelomic spread

Question 16

Trans-coelomic spread?

Answer 16

Special form of local spread
spreading across a body cavity, such as through the pleural, pericardial, or peritoneal cavity.
tumours of lung, stomach, colon and ovary show this spread

Question 17

Tumour metastasis via blood

Answer 17

• adherence of tumour cells to blood vessels
• invasion from blood vessels
• invasion into tissue
• formation of metastasis
• clinical evidence of metastasis

Question 18

Tumour metastasis via lymphatics

Answer 18

adherence of tumour cells to lymph vessels

• invasion from lymphatics
• invasion into lymph node
• formation of metastasis in lymph node
• clinical evidence of metastsis

Question 19

Common sites of metastasis

Answer 19

liver
lung
brain
bone- axial skeleton
adrenal gland
omentum/ peritoneum (abdomen membrane)

Question 20

Uncommon sites of metastasis

Answer 20

spleen
kidney
skeletal muscle
heart

Question 21

What is a tumour marker?

Answer 21

Tumour markers are substances that are produced by cancer or by other cells of the body in response to cancer or certain benign (noncancerous) conditions.

Most tumour markers are made by normal cells as well as by cancer cells; however, they are produced at much higher levels in cancerous conditions.

Can be found in the blood, urine, stool, tumour tissue, or other tissues or bodily fluids of some patients with cancer. Most tumour markers are proteins.

Question 22

Issues with tumour markers?

Answer 22

• non-cancerous conditions can cause the levels of certain tumour markers to increase
• not everyone with a particular type of cancer will have a higher level of a tumour marker associated with that cancer
• tumour markers have not been identified for every type of cancer

Question 23

How are tumour markers used in cancer care?

Answer 23

help detect, diagnose, and manage some types of cancer

Tumour marker levels may be measured before treatment to help doctors plan the appropriate therapy

Question 24

Tumour markers being used throughout treatment help to do what?

Answer 24

Tumour markers may also be measured periodically during cancer therapy. A decrease in the level of a tumour marker or a return to the marker’s normal level may indicate that the cancer is responding to treatment, whereas no change or an increase may indicate that the cancer is not responding.

Question 25

Tumour markers may also be measured after treatment to check for what

Answer 25

to check for recurrence

Question 26

Define ‘pleomorphism’

Answer 26

vary in size and shape

Question 27

Examples of tumour suppressor genes

Answer 27

Adenomatous polyposis (APC)
Retinoblastoma (Rb)
BRCA1

Question 28

General main classes of tumour biomarkers

Answer 28

onco-fetal proteins, oncogenes, growth factors and receptors, immune checkpoint inhibitors

Question 29

Onco-fetal proteins

Answer 29

expressed normally in fetal tissues. Switched off in post-fetal life but switched back on in tumours

Question 30

Alpha-fetoprotein

Answer 30

one of the main proteins expressed in fetal liver
expression is switched off in post-fetal life. Good for identifying malignant testicular teratoma and hepatocellular carcinoma (malignant)

Question 31

Carcino-embryonic antigen (CEA)

Answer 31

indicator of colorectal cancer
CEA is switched off post-natal life then switched back on in tumours
Use this marker to monitor response/progression of tumour after treatment

Question 32

Receptors that can detect breast cancer?

Answer 32

Breast cancer cells often have receptors (proteins) that hormones or other proteins can attach to and stimulate the cancer to grow
Oestrogen receptor:- Breast cancers with receptors for the hormone oestrogen

Some breast cancers have high numbers of receptors for the protein HER2 (human epidermal growth factor

Question 33

Prostate specific antigen biomarker?

Answer 33

Useful in terms of possible diagnosing but certainly monitoring therapy and progression of prostate cancer.
Commonly used clinical bio-marker

Question 34

Kras is a useful biomarker to predict which tumour?

Answer 34

colorectal cancer

Question 35

Braf is a useful biomarker to predict which tumour?

Answer 35

melanoma

Question 36

EGFR (epidermal growth factor receptor) is a useful biomarker to predict which tumour?

Answer 36

renal cancer

Question 37

PD-L1 is a useful biomarker to predict which tumour?

Answer 37

lung cancer

Question 38

Her 2 is a useful biomarker to predict which tumour?

Answer 38

Breast and gastric cancer
Her2 is part of the EGFR family
Herceptin is used to select patients for herceptin treatment for breast cancer and gastric. The drug binds to Her2 molecule (it is a receptor)

Question 39

pleomorphism?

Answer 39

Varying in size and shape

Question 40

Clinical evidence of metastasis in lymphatics

Answer 40

imaging
feeling of large lymph nodes
histology- most sensitive way