Cervical Screening

Question 1

Which cancers have HPV as a major cause?

Answer 1

Cervical, penile, vulva/vaginal, anus

-Less commonly: mouth and oropharynx

Question 2

What is the name given to an abnormal growth of squamous cells detectable on a smear?

Answer 2

Squamous intraepithelial lesion (can be low or high grade)

Question 3

What is the name given to abnormal cells in the cervix detected by biopsy and histological examination?

Answer 3

Cervical intraepithelial neoplasia (graded 1-3 depending on the proportion of cervix affected)

Question 4

How likely is there to be a genetic link to cervical cancer?

Answer 4

Unlikely

Question 5

How are cervical smears tested?

Answer 5

• 5 yearly
• Tested for high risk HPV
• If HPV is positive then cytology is done
• If cytology shows dyskaryosis then referred for colposcopy and biopsy

Question 6

What are the two types of epithelium found in the cervical canal?

Answer 6

• Columnar epithelium (endocervix)

- Squamous epithelium (ectocervix)

Question 7

What can be seen on cytology that reflects a HPV infection?

Answer 7

Koilocytes

Question 8

What effect does HPV have in the transformation zone?

Answer 8

• Infects basal layer cells
• Utilises host for replication
• As host cell matures, different viral genes are expressed

Question 9

What are the high risk types of HPV?

Answer 9

16,18, 31 and 45

Question 10

How does HPV cause high grade CIN?

Answer 10

• Viral DNA integrates into the host cell genome
• Overexpression of viral E6 and E7 proteins
• Deregulation of host cell cycle