Cervical Screening

Question 1

What percentage of cervical cancers are HPV-related?

Answer 1

> 99%

Question 2

What other cancers can be caused by HPV than cervical?

Answer 2

• Penis
• Vulva/vagina
• Anus
• Mouth
• Oropharynx

Question 3

How are HPV immunisations given in the UK?

Answer 3

The UK HPV immunisation schedule currently involves a quadrivalent vaccine against HPV 16, 18, 6 and 11. This increased in 2012 from a bivalent vaccine against HPV 16 and 18

Question 4

How are screening samples for cervical cancer taken?

Answer 4

• Women aged 25-64 years
• 5 yearly smears
• Liquid Based Cytology (LBC)
• Test for high risk HPV
• If positive; triage with cytology

Question 5

What is abnormal cytology of the cervix known as?

Answer 5

Dyskaryosis

Question 6

What are the cytological features of dyskaryosis?

Answer 6

• Increased size and nuclear:cytoplasmic ratio
• Variation in size, shape and outline
• Coarse irregular chromatin
• Nucleoli

Question 7

What steps need to be taken after cervical screening testing?

Answer 7

• Negative- recall at routine five years
• Positive for hrHPV but normal cytology- repeat test after one year
• Dyskaryosis- refer for colposcopy

Question 8

What is involved in colposcopy?

Answer 8

• Magnification and light to see cervix
• Exclude obvious malignancy
• Use of acetic acid =/- Iodene to identify the limits of lesion, select the biopsy site or define area to treat

Question 9

What are the options for management during colposcopy?

Answer 9

• Punch biopsy to make a diagnosis
• Return for Treatment if CIN2/3
• “See and treat” at first visit

Question 10

How does HPV infection affect the cervix?

Answer 10

HPV infects the basal layer of the transformation zone, utilising the host for reception. As the host cell matures, different viral genes are expressed

Question 11

What are the high risk types of HPV?

Answer 11

16, 18, 31 and 45

Question 12

How does HPV infection cause CIN?

Answer 12

HPV causes high risk CIN as a result of persistent infection causing the following processes:
•Viral DNA integrates into host cell genome
•Overexpression of viral E6 and E7 proteins
•Deregulation of host cell cycle

Question 13

How is CIN graded?

Answer 13

• CIN 1: low grade dysplasia–will regress
• CIN 2: moderate dysplasia – may regress
• CIN 3: severe dysplasia – unlikely to regress

Question 14

How is CIN treated?

Answer 14

LLETZ, thermal coagulation or laser ablation

Question 15

Why should treatment of CIN be followed up?

Answer 15

• Confirm effectiveness of treatment
• Prevent invasive cancer
• Reassure patient
• Increased risk of cervical cancer