Abnormal cell growth

Question 1

What is agenesis?

Answer 1

A partial or complete absence of an organ or cells

Question 2

What is aplasia?

Answer 2

Complete absence of an organ, with some undeveloped embryonic cells present

Question 3

What is hypoplasia? What is it also known as? Give an example

Answer 3

Underdeveloped organ, resulting in smaller size
AKA dysgenesis
e.g. micro-ophthalmia

Question 4

What is dysgraphics? Give an example

Answer 4

Structures are present but are not fused together as they should be
e.g. Spina Bifida

Question 5

What is hypertrophy? Give an example

Answer 5

Increased cell and organ size
e.g. the uterus during pregnancy

Question 6

What is hyperplasia? Why does it occur? Give an example

Answer 6

Increased cell number
Due to hormonal stimulation, increased functional demand or repeated injury
e.g. lactation

Question 7

What is atrophy? Why does it occur?

Answer 7

Reduced cell size/number
Due to reduced workload, innervation, blood supply or nutrition, reduced cell synthesis or an increased metabolism

Question 8

What is metaplasia? Why does it occur?

Answer 8

Change from one cell type to another
Due to repeated injury - multiple layers created as more protective

Question 9

What is dysplasia? When does it occur?

Answer 9

Change in size, shape and organisation of the tissue
Happens after metaplasia but before neoplasia

Question 10

What is neoplasia?

Answer 10

Formation of a tumour

Question 11

What is carcinoma in situ?

Answer 11

Dysplasia is present throughout all cell layers but the basement membrane is still intact
Nuclei change shape and size
Proteins (keratin) are made by each cell
Cells lose polarity

Question 12

What is carcinoma?

Answer 12

Epithelial neoplasm

Question 13

What is sarcoma?

Answer 13

Connective tissue, muscle or bone neoplasm

Question 14

What is leukaemia/lymphoma?

Answer 14

blood or lymph neoplasm

Question 15

What is myeloma?

Answer 15

Bone marrow neoplasm

Question 16

What is blastoma?

Answer 16

Malignant precursor cells

Question 17

What is teratoma?

Answer 17

Tumour made up of many cell types, originating from multiple germ layers

Question 18

Where is adenomatous cancer?

Answer 18

Duct or gland cells

Question 19

Where is squamous cancer?

Answer 19

Epithelial cells

Question 20

Where is myeloid cancer?

Answer 20

Blood cells

Question 21

Where is lymphoid cancer?

Answer 21

Lymphocyte cells

Question 22

Describe the stages of cervical carcinoma

Answer 22

1. Endocervical cells begin as columnar epithelium, ectocervical cells begin as squamous epithelium
2. Squamous cells undergo metaplasia, which eventually spreads into columnar cells
3. Eventually the metaplastic cells enter the dysplastic stage
4. Once dysplasia is full thickness, carcinoma in situ occurs

Question 23

Describe the stages of metastasis

Answer 23

1. Carcinoma in situ breaks through the basement membrane by releasing enzymes to degrade it (carcinoma now known as invasive carcinoma)
2. Cells travel towards blood or lymphatic vessels via ECM, binding along laminin and fibronectin and releasing degrading enzymes to clear a path
3. Cells enter circulation and avoid immune detection
4. Once at new site, cells exit vessels by endothelial cell rolling and diapedesis
5. Cells stimulate angiogenesis via release of growth factors - blood vessels created to provide tumour nutrients

Question 24

Describe the stages of tumour initiation

Answer 24

1. Proto-oncogene mutates, becoming oncogene which encourages tumour growth
2. Tumour suppressor gene also mutates or loses its function
3. Cells allowed to proliferate uncontrollably, creating neoplasm

Question 25

When are choroidal and iris naevi benign?

Answer 25

When smaller than 2 disc sizes

Question 26

When are choroidal and iris naevi malignant?

Answer 26

When larger than 5 disc sizes

Question 27

What percentage of ocular melanomas are choroidal? What age are they mot common?

Answer 27

80% 55-65 years

Question 28

What gene is mutated in retinoblastoma?

Answer 28

Rb

Question 29

How does inherited retinoblastoma occur? Is it more likely to be uni- or bilateral? What percentage of retinoblastoma is inherited?

Answer 29

Usually one mutated gene is inherited, and another mutates Bilateral more likely 25-30% inherited

Question 30

How does sporadic retinoblastoma occur? Is it more likely to be uni- or bilateral?

Answer 30

Random mutation of one gene in a parent cell, and a second mutation occurs in the same or daughter cell Unilateral more likely