11. Neoplasms

Question 1

How many new cases of cancer were there worldwide in 2012?

Answer 1

14 million.

Question 2

How many people died, worldwide, from cancer?

Answer 2

8.2 million.

Question 3

What are the top three, most prevalent cancers?

Answer 3

Breast, lung and prostate.

Question 4

How can looking at the most common cancers be helpful to a doctor?

Answer 4

It can provide a starting place for diagnosis.

Question 5

Which cancer is responsible for most deaths in the UK?

Answer 5

Lung.

Question 6

What factors are considered when considering outcome of cancers?

Answer 6

Age and general health of the patient. Tumour site, type, grade and stage. Also the availability of treatments.

Question 7

What does TNM stand for in cancer staging?

Answer 7

T = size of primary tumour: T1-T4.
N = extent of regional node metastasis: N0-N3.
M = extent of distant metastatic spread: M0 or M1.

Question 8

What are the four stages generally referring to?

Answer 8

Stage I - early local disease.
Stage II - advanced local disease.
Stage III - regional metastasis.
Stage IV - advanced disease with distant metastasis.

Question 9

What is the Ann Arbor staging used for?

Answer 9

Lymphomas.

Question 10

What are the four stages in Ann Arbor staging?

Answer 10

I - single node region.
II - two separate regions on one side of the diaphragm.
III - spread to both sides of the diaphragm.
IV - diffuse or disseminated involvement of one or more extra lymphatic organs such as bone marrow or lungs.

Question 11

What is Duke’s staging used for?

Answer 11

Colorectal carcinoma.

Question 12

What are the stages A-D of Duke’s staging?

Answer 12

A - invasion into but not through the bowel.
B - invasion through the bowel wall.
C - involvement of lymph nodes.
D - distant metastasis.

Question 13

What are the four grades of neoplasia?

Answer 13

G1 - well-differentiated.
G2 - moderately differentiated.
G3 - poorly differentiated.
G4 - undifferentiated or anaplastic.

Question 14

Which neoplasms is the grading system generally used for?

Answer 14

Squamous cell carcinoma and colorectal carcinoma.

Question 15

Which neoplasm is the Bloom-Richardson system used for?

Answer 15

Breast cancer.

Question 16

What does the Bloom-Richardson assess?

Answer 16

Grading, by looking at: tubule formation, nuclear variation and number of mitoses.

Question 17

Why is tumour grading important?

Answer 17

It helps plan treatment and estimates prognosis in certain types of malignancy, the link between grade and prognosis is displayed especially well with breast carcinoma.

Question 18

How can cancer be treated?

Answer 18

By surgery, radiotherapy, chemotherapy, hormone therapy, and treatment targeted to specific molecular alterations.

Question 19

What is the typical curative treatment of cancer?

Answer 19

Surgery.

Question 20

What is adjuvant treatment?

Answer 20

Treatment given after surgical removal of a primary tumour to eliminate subclinical disease.

Question 21

What is neoadjuvant treatment?

Answer 21

Treatment given to reduce the size of a primary tumour prior to surgical excision.

Question 22

Why is radiatiotherapy given in fracitonated does?

Answer 22

It minimises normal tissue damage whilst still damaging malignant cells.

Question 23

How does radiotherapy work?

Answer 23

X rays or other ionising radiation is used to kill rapidly dividing cells, especially in G2 of the cell cycle. The high dose causes either direct or free-radical induced DNA damage that is detected by the cell cycle check-points, triggering apoptosis. Double-stranded DNA breakages cause damaged chromosomes that prevent M phase from completing correctly.

Question 24

How do antimetabolites work?

Answer 24

They mimic normal substrates involved in DNA replication.

Question 25

How do alkylating and platinum-based drugs work?

Answer 25

They cross-link the two strands of DNA helix. So the M phase of the cell cycle can’t be completed.

Question 26

How do plant-derived drugs work?

Answer 26

They block microtubule assembly and interfere with mitotic spindle formation.

Question 27

How do SERMs (selective oestrogen receptor modulators) work?

Answer 27

They bind to oestrogen receptors to prevent oestrogen from binding in hormone receptor-positive breast cancer.

Question 28

Which mutation can be looked at to specifically target drugs at cancer cells

Answer 28

Alterations like oncogene mutations.

Question 29

What can tumour biomarkers be used for?

Answer 29

Diagnosis, and monitoring tumour burden during treatment and as a follow up.

Question 30

What is the purpose of cancer screening?

Answer 30

Detect cancers as early as possible when the chance of cure is the highest.

Question 31

What are three problems with cancer screening?

Answer 31

Lead time bias, length bias and over diagnosis.

Question 32

What is lead time bias in cancer screening?

Answer 32

Without screening, the patient may live for 3 years after diagnosis. But with lead time bias, the diagnosis date moves forward, which means, although the death date is the same, the time from diagnosis is longer. This can skew 5 year mortality rates as it appears the patient lives longer, when actually they still die at the same time.

Question 33

What is length bias in cancer screening?

Answer 33

Slow growth cancers are more likely to be picked up at screening than rapid growth, which are only picked up in diagnosis. This means that the cancers that may have never clinically presented are picked up which may not be beneficial to the patient and also exaggerates the usefulness of screening programmes.

Question 34

What is over diagnosis in cancer screening?

Answer 34

The cancers detected may have been unlikely to have developed in that person’s lifetime to become a clinical problem. So the patient may undergo unnecessary treatment for a cancer, that actually, may not have ever been a problem.