L15 - Neoplasia 1

Question 1

Define the following:
a) neoplasm
B) malignant neoplasm
c) dysplasia
d) tumour
e) cancer
f) metastasis
g) anaplasia

Answer 1

A) Neoplasm - An abnormal growth of cells that persists after the initial stimulus is moved
B) Malignant neoplasm - An abnormal growth of cells which persists after the initial stimulus is removed AND invades the surrounding tissue with a potential to spread to distant sites
C) Dysplasia - A reversible abnormal maturation of cell within a tissue that aren’t normally present
d) tumour - Any clinically detectable lump or swelling, a neoplasm is a form of tumour
e) cancer - any malignant neoplasm
f) metastasis - a malignant neoplasm which has spread to a new site
g)Anaplasia - A malignant neoplasm in which the cells have no resemblance to the parent tissue

Question 2

Define
A) dysplasia
B)pleomorphism
C)progression
D) differentiation
E) in situ

Answer 2

A) A reversible abnormal maturation of cell within a tissue that aren’t normally present. Often pre-neoplastic’
B) increased variation in size and shape of cells and nuclei in a given population (a sign of worsening differentiation and malignancy)
C) the cause of a neoplasm characterised by the accumulation of yet more mutations
D) obvious
E) no invasion through epithelial basement membrane

Question 3

Why are benign tumours less dangerous than malignant ones?

Answer 3

Because they are confined to a local area/ have a regular outer margin/ don’t show necrosis/do not have any metasteses

Whereas malignant ones have an irregular outer margin and shape/ may show areas of necrosis and ulceration/ have the potential to produce metasteses

Question 4

Under the microscope how would a benign neoplasm look compared to its parent tissue?

Answer 4

Similar, well differentiated

Question 5

Name the 4 major signs of worsening differentiation seen in malignant cells under the microscope

Answer 5

• Increased nuclear size and nuclear:cytoplasm ratio
• Hyperchromasia (increased nuclear staining)
• More mitotic figures (nucleus is seen as tangled darkly stained threads instead)
• Pleomorphism

Question 6

What term is clinically used to indicate the level of differentiation?

Answer 6

Grade. A high grade means being poorly differentiated aka poorly resembling the parent tissue

Question 7

Distinguish between initiators and promoters

Answer 7

• Initiators are the mutagenic agents which cause the mutation
• promoters cause the cell proliferation

Question 8

Describe the macroscopic appearance of malignant compared to benign tumours

Answer 8

Malignant tumours have an irregular outer margin and may show areas of necrosis and ulceration whilst benign have a regular pushing outer margin

Question 9

Initiators and promoters together form a monoclonal group of cells called a neoplasm. T/F?

Answer 9

T

Question 10

What is the name of the process which describes the random inactivation of one X chromosome in female embryogenesis?

Answer 10

Lyonisation

Question 11

Evidence showing that tumours are monoclonal came from a study on women with deficiency of what enzyme in their tumour tissue?

Answer 11

Glucose-6-phosphate dehydrogenase

Question 12

Which genes become abnormally activates in neoplasm formation and which become inactivated?

Answer 12

Activates - Proto-oncogenes which are then called oncogenes

Tumour suppressor genes are inactivated to favour neoplastic formation

Question 13

Benign neoplasms end with what suffix? What is the suffix for malignant neoplasms?

Answer 13

Benign = -oma
Malignant = -carcinoma if it’s epithelial (90% of time) -sarcoma (10% of time) if its a stromal malignancy 

Note - stroma is the supportive network of an organ - usually composed of connective tissue

Question 14

Describe the following:

Leukemia, lymphoma, myeloma, germ cell neoplasm, neuroendocrine neoplasms, -blastomas, papilloma

Answer 14

Leukemia - malignant neoplasm of blood forming cells arising in the bone marrow
Lymphoma - malignant neoplasms of lymphocytes mainly affecting lymph nodes
Myeloma - malignant neoplasm of plasma cells
Germ cell neoplasms - arise from pluripotent cells in the testis or ovary
Neuroendocrine rumours - arise from cells distributed throughout the body
-blastomas - mainly occurs in children because they are formed from immature cells
Papilloma - cyst forming, generally on skin or mucous membranes in non-secretory or non-glandular epithelium

Question 15

How can benign tumours cause problems?

Answer 15

Pressure on adjacent tissues/ obstruction of flow of fluids/production of a hormone/transformation into a malignancy/anxiety

Question 16

Benign epithelial tumours are either papillomas or adenomas, what is meant by this?

Answer 16

Papillomas occur in non-glandular of non-secretory epithelium typically in transitional or stratified squamous epithelium

Adenomas occur in glandular or secretory epithelium e.g.

Question 17

Leiyomyomas and lipomas are benign mesenchymal tumours, where do these occur?

Answer 17

In the mesenchyme - loose connective tissue

Question 18

What is the main histological characteristic of Hodgkin’s lymphoma (in B cells)?

Answer 18

The presence of Reed-Sternberg cells (googly eyes) - this is a malignant lymphoma

Question 19

Teratomas are neoplasms of germ cell origin. They are most commonly found in the gonads where the germ cells are most abundant. In the ovaries they commonly form cysts and solid lumps in the testis, how can they often look under the microscope

Answer 19

Scary looking - tumour may have teeth and hair and contain epithelium, cartilage, neural tissue basically features of each of the germ layers in one cell

Question 20

Which type of cancers most commonly arise from the following organs:
-bladder
-bowel
-skin
-lung
-breast
-breain
-prostate
-pancreas
-uterus
-oesophagus
-stomach
-thyroid
-cervix
Give two tissues which generally don't form adenocaricinomas

Answer 20

NOTE - basal cell carcinomas tend to affect places reached by the sun
Bladder - transitional cell carcinoma
Bowel - adenocarcinoma
Skin - squamous cell carcinoma/malignant melanoma/basal cell carcinoma
-Lung - adenocarcinoma, squamous celll carcinoma, small cell carcinoma
-breast - adenocarcinoma
-prostate - adenocarcinoma
-pancreas - adenocarcinoma
-uterus - adenocarcinoma
- oesophagus - adenocarcinma, squamous cell carcinoma
-stomach - adenocarcinoma
-thyroid -adenocarcinoma
-cervix - squamous cell carcinoma, adenocarcinoma

Question 21

Adenocarcinomas and adenomas seem to be one of the most common type of neoplasms, they’re described as ‘gland forming’ T or F ?

Answer 21

T