14.5 Clinical aspects of cancer

Question 1

How may a tumour affect the body?

Answer 1

1. Compete with normal body cells for nutrients and energy transported in the bloodstream
2. Return waste materials to the bloodstream, which the body must process and eliminate
3. Secrete substances that affect the person e.g. adrenaline
4. Grow so large that it can press against body organs, causing pain
5. Block the function of a vital organ, causing death

Question 2

What is xeroderma pigmentosum (XP)?

Answer 2

A rare pre-malignant condition as a result of a gene mutation, whereby the skin loses its ability to repair itself from exposure to UV light

Question 3

What is solar keratosis?

Answer 3

A pre-malignant condition occurring from years of exposure to the sun. Skin becomes rough and scaly

Question 4

What is vulval intra-epithelial neoplasia (VIN)?

Answer 4

Pre-malignant skin condition of the vulva, symptoms intense and persistent itch. Many linked to HPV

Question 5

What is cervical intra-epithelial neoplasia (CIN)?

Answer 5

Pre-malignant cell changes that occur in the cervix

Question 6

What is Barrett’s oesophagus?

Answer 6

People who suffer from gastro-oesophageal reflux disease (GORD) are at risk of developing Barrett’s oesophagus

Question 7

What is the screening process for breast cancer?

Answer 7

Mammogram. In the UK, all women aged 50-70 and registered with a GP are automatically invited for breast screening every three years

Question 8

What is the screening process for cervical cancer?

Answer 8

Smear test. All women between 25-60 are invited for screening every 3-5 years

Question 9

What is the scale of cervical intraepithelial neoplasia (CIN)?

Answer 9

An abnormal test result will say:
CIN 1 - mild cell changes (mild dyskaryosis)
CIN2 - moderate cell changes (moderate dyskaryosis)
CIN3 - severe cell changes (severe dyskaryosis)

Question 10

What happens if a patient has CIN2 or CIN3?

Answer 10

They will be referred for a colposcopy biopsy, and if necessary receive treatment

Question 11

What is the screening process for bowel cancer?

Answer 11

Faecal occult blood (FOB) test. All men and women aged 60 to 74 are invited to carry out FOB test at home. Test will not establish bowel cancer, but indicates whether a colonoscopy is required

Question 12

What is the screening process for prostate cancer?

Answer 12

Blood test to detect the level of prostate specific antigen (PSA). If PSA level raised, other tests used e.g. digital rectal exam (DRE), biopsy. No screening programme in UK

Question 13

How are cancers staged?

Answer 13

Stage 1 - the tumour is still small and has not spread outside the original site
Stage 2 - the tumour is still localised, but is larger than stage 1. Stage 2 may also refer to a cancer that has spread to nearby lymph nodes, depending on the type of cancer
Stage 3 - a tumour which has spread into nearby tissues and cancer cells are detected in nearby lymph nodes
Stage 4 - a tumour which has spread more widely to other, often distant, organs. This is known as secondary cancer, or metastatic disease

Question 14

What is tumour grading?

Answer 14

Describes how similar the cancer cells are to normal cells of the same type, and how abnormal the tissue looks under the microscope (histopathology). Can be described as high or low or 1-4; low grade cancer cells look most like normal cells

Question 15

What is cancer grading based on?

Answer 15

How differentiated cells appear under the microscope. High grade cancer cells are undifferentiated and look least like normal cells

Question 16

What are features of poorly differentiated cancer cells?

Answer 16

They have lost all of the features that characterise the tissue of origin:
More mitochondria than a normal cell (to process the energy for growth)
More ribosomes (as protein is needed for cell division)
The nucleus may change in size and shape

Question 17

What is anaplasia?

Answer 17

The reversion to undifferentiated, unspecialised cells; these are known to lead to the formation of cancer

Question 18

Describe cell structures in cancer cells (e.g. mitochondria, ribosomes)

Answer 18

May be abnormal. May be detectable under microscope in biopsy of tumour

Question 19

Describe cell membranes in cancer cells

Answer 19

Abnormal proteins on surface. These may be measurable in blood and can be used to identify specific tumours (tumour markers)

Question 20

Describe protein synthesis in cancer cells

Answer 20

Increased; proteins are needed for mitosis

Question 21

Describe DNA in cancer cells

Answer 21

Mutated. Mutations in proto-oncogenes or tumour suppressor genes are the likely cause of cancer

Question 22

Describe cell proliferation in cancer cells

Answer 22

Uncontrolled, purposeless. The higher the proliferative potential of the cancer cells, the worse the probable prognosis for the patient

Question 23

Describe cell differentiation in cancer cells

Answer 23

Less differentiated or undifferentiated. The less differentiated the cancer cell, the worse the probably prognosis for the patient

Question 24

What is molecular pathology?

Answer 24

Utilisation of molecular and genetic approaches to diagnose disease. Refers to the analysis of proteins, DNA/RNA, and other biological molecules in the context of disease. Can be used to classify tumours and direct treatment

Question 25

What does the time to death in cancer depend on?

Answer 25

1. Rate of tumour growth
2. Degree of metastasis and sites affected by metastases
3. Rate of growth of metastases
4. Whether or not the person is treated