S1) Introduction

Question 1

What is pathology?

Answer 1

The study of suffering

Question 2

Why is microscopic diagnosis important? (2)

Answer 2

• Definitive

- Required before surgery to remove a lesion

Question 3

Distinguish between Histology and Cytology

Answer 3

Histology uses microscopic slides from tissue sections

Cytology uses cells from an organ, lesion or bodily fluid

Question 4

4 advantages of cytology

Answer 4

• Non-invasive
• Fast
• Cheap
• Safe

Question 5

Main disadvantage of cytology

Answer 5

Higher error rates than histology

Question 6

Two uses of cytology

Answer 6

1) Preliminary test before other investigations

2) Confirm/ exclude cancer

Question 7

4 advantages of histology

Answer 7

• Differentiates between in situ and invade malignancy
• Determines completeness of excision
• Allows for grading and staging
• Assesses cell architecture and cellular atypia

Question 8

Which two additional tests are needed before producing slides for microscopy?

Answer 8

Immunohistochemistry

Molecular pathology

Question 9

5 antigenic substances which can be detected by immunohistochemistry

Answer 9

Actin
Cytokeratins
Microorganisms eg HPV or herpes
Hormone receptors eg oestrogen or Her2

Question 10

What does molecular pathology study?

Answer 10

DNA/ RNA and proteins

Question 11

What is the Her2 receptor?

Answer 11

A growth factor receptor which predicts the response of breast cancer to Herceptin

Question 12

What are cytokeratins?

Answer 12

Fibrous proteins present in almost all epithelia

Question 13

Why do we detect cytokeratins? (2)

Answer 13

• They demonstrate epithelial differentiation

- Give information about the primary site of a carcinoma

Question 14

Where can serous carcinoma occur? (5)

Answer 14

• Ovary
• Fallopian tube
• Uterus
• Cervix
• Peritoneum

Question 15

The stage of cancer is based on what 3 variables?

Answer 15

1) Size of tumour
2) Has it affected the lymph nodes?
3) Level of metastasis

Question 16

8 steps of tissue preparation

Answer 16

1) Fixation
2) Choosing the tissue
3) Hardening the tissue
4) Insertion into metal blocks
5) Cutting thin sections with a microtome
6) Staining
7) Preservation and protection
8) Diagnosis

Question 17

Why do we need to fix the tissue?

What does formalin do?

Answer 17

• Tissue autolysis occurs when blood supply is cut off

1) Inactivates enzymes and denatures proteins
2) Prevents bacterial growth
3) Hardens tissues

Question 18

What do we use to harden the tissue/ why?

Answer 18

Paraffin wax, after removing the water via alcohol and then xylene

Needed so tissue can be sliced