MoD 9 Neoplasia

Question 1

What is a neoplasm?

Answer 1

An abnormal growth of cells that persists after the initial stimulus is removed

Question 2

What is a malignant neoplasm?

Answer 2

An abnormal growth of cells that persists after the initial stimulus is removed and invades surrounding tissue with potential to spread to distant sites

Question 3

What is a tumour?

Answer 3

Any clinically detectable lump or swelling

Question 4

What is a cancer?

Answer 4

A malignant neoplasm

Question 5

What is a metastasis?

Answer 5

A malignant neoplasm that has spread from its original site to a new non-contiguous site

Question 6

How is the behaviour of benign and malignant neoplasms different?

Answer 6

Benign neoplasms remain confined to their site of origin while malignant neoplasms can metastasise

Question 7

How are benign and malignant neoplasms different to the naked eye?

Answer 7

Benign grow in a confined local area and so have a pushing outer margin while malignant tumours have an irregular outer margin and shape and may show areas of necrosis and ulceration if on a surface

Question 8

What type of cells do benign neoplasms have?

Answer 8

Cells closely resembling the parent tissue i.e. well differentiated

Question 9

What type of cells do malignant neoplasms have?

Answer 9

Can range from well differentiated to poorly differentiated

Question 10

What are anaplastic cells?

Answer 10

Cells having no resemblance to any tissue

Question 11

What can be seen in poorly differentiated cells under the microscope?

Answer 11

Increasing nuclear size
increasing nuclear:cytoplasmic ratio
Nuclear hyperchromasia
more mitotic figures
increasing variation in shapes and size of cells and nuclei (pleomorphism)

Question 12

How are neoplasms graded?

Answer 12

High grade poorly differentiated
Low grade well differentiated
G1, G2, G3

Question 13

What can dysplasia mean other than abnormal development?

Answer 13

Altered differentiation. Mild, moderate and severe indicating worsening differentiation

Question 14

What are the steps in worsening differentiation of skin?

Answer 14

Reversible change- dysplasia - loss of keratin and reduced specialisation
Irreversible- carcinoma in situ - basement membrane intact
Invasive carcinoma- tripolar mitosis, destruction of basement membrane

Question 15

Is neoplasia caused by singular mutations?

Answer 15

No, accumulated mutations

Question 16

What is an initiator?

Answer 16

Mutagenic agent

Question 17

What is a promoter?

Answer 17

Agents causing cell proliferation

Question 18

What combination of initiators and promoters causes mutation?

Answer 18

Initiator followed by prolonged promotion

Question 19

What does the combination of initiators and promoters result in?

Answer 19

Monoclonal population of mutant cells

Question 20

What are the main initiators?

Answer 20

Chemicals, infections and radiation

some of these can act as promoters too

Question 21

Are mutations in neoplasms always from an external mutagenic agent?

Answer 21

No, sometimes germline mutation gives head start

Question 22

What is progression?

Answer 22

the accumulation of more mutations in a monoclonal population causing a neoplasm

Question 23

How do we know that neoplasms are monoclonal?

Answer 23

Study of X-linked gene for glucose-6-phosphate dehydrogenase (G6PD) in tumour tissue from women.
Early in embryogenesis one allele in each cell is inactivated randomly (lyonisation). Neoplastic tissues only express one isoenzyme indicating a monoclonal group of cells

Question 24

Mutations in what two type of genes that regulate the cell cycle favour neoplasm formation?

Answer 24

Proto-oncogenes are activated to oncogenes
Tumour supressor genes become inactivated
A combination of numerous of each must mutate to cause neoplasms

Question 25

What do benign neoplasms end in?

Answer 25

-oma

Question 26

What do epithelial malignant neoplasms end in?

Answer 26

-carcinoma

Question 27

What do stromal malignant neoplasms end in?

Answer 27

-sarcoma

Question 28

What two types of carcinomas can there be?

Answer 28

in-situ: no invasion of epithelial basement membrane

invasive: penetrates basement membrane

Question 29

What is leukaemia?

Answer 29

malignant neoplasm of blood forming cells arriving in the bone marrow

Question 30

What are lymphomas?

Answer 30

Malignant neoplasms of lymphocytes mainly affecting lymph nodes

Question 31

What do germ cell neoplasms arise from?

Answer 31

Pluripotent cells mainly in testis or ovary

Question 32

What do neuroendocrine tumours arise from?

Answer 32

Cells distributed throughout body

Question 33

What are blastomas?

Answer 33

Neoplasms occurring mainly in children formed from immature precursor cells e.g nephroblastoma

Question 34

What are the four polyp names?

Answer 34

papilloma- finger like projections
cecil- long bump shape
predunculated- bud shape
cyst

Question 35

What are glandular benign neoplasms called?

Answer 35

adenomas

Question 36

What type of neoplasm are 90% of cancers?

Answer 36

Carcinomas (epithelial)

Question 37

What type of neoplasms are lymphomas?

Answer 37

malignant

Question 38

Where are teratomas found?

Answer 38

Malignant- testis

Benign- ovary

Question 39

What two types of neoplasms are found in the testis?

Answer 39

Malignant teratoma

Seminoma (malignant)

Question 40

What are benign teratomas also known as and what can they contain?

Answer 40

Dermoid cysts

Teeth, hair etc