Cervical neoplasia 1 Flashcards
When was papillomavirus first suggested as a cause of cervical cancer?
1976
When was the HPV 16/18 genome cloned from cervical cancers?
1983-1984
When was it found that HPV DNA is present in a large % of cervical cancers?
1999
What % of cervical cancers had HPV DNA present in them?
99.7%
When was the HPV vaccine introduced?
2006-2008
What age range has the peak incidence of cervical cancer?
30-34 yrs
Risk factors for cervical cancer?
HPV infection (high risk), smoking, use of oral contraceptive pill, family history
How is the effect of smoking two fold on the risk of cervical cancer?
Mutagenic effect of smoking on your body, and the impact of smoking on the immune system
How does HPV spread?
Skin to skin contact
What is the cumulative lifetime risk of a HPV infection?
80%
How long do most HPV infections last?
Transient–> 6-12 months
Which type of HPV infections can cause cervical disease?
Persistent ones (less than 10% of cases)
How many HPV genotypes have been identified?
~200
What general areas can HPV infections affect?
Mucosal and cutaneous surfaces
What specific areas can HPV infections affect?
Mouth, skin, anogenital tract, respiratory tract
Which are the high risk subtypes of cervical cancer?
16 and 18 mainly (also 31, 33, 34, 35)
What % of cervical cancers are caused by HPV16 in the uk?
50%
What % of cervical cancers are caused by HPV18 in the uk?
20%
Where on the body does cutaneous HPV infections affect?
Warts on hands and feet
Facts ab cutaneous HPV subtypes?
Occurs often in children, resolve spontaneously in 1-5 years
Where on the body can mucosal HPV subtypes affect?
Mouth, respiratory tract, anogenital tract
Low risk HPV subtypes?
6, 11, 42, 43, 44
What does low risk mucosal HPV subtypes cause?
Genital warts, low grade changes in cervix (but not cancer)
Which cancers are high risk HVP subtypes associated with?
Cervical cancer, anal cancer, cancers of mouth and throat
What is the cervix?
“neck” of the uterus/womb
What lines the endocervical canal?
Columnar epithelium
What lines the ectocervix?
SSQE
What is the squamocolumnar junction?
Where the columnar epithelium of the endocervical canal and the SSQE of the outer cervix join
What is unique ab the squamocolumnar junction’s movement?
Dynamic–> usually in the canal but can move out into the outer cervix (during puberty, pregnancy and high oestrogen states)
What happens to glandular epithelium is exposed to an acidic environment?
It undergoes metaplasia into SSQE
What is the cervical transformation zone?
Area where the endocervical epithelium undergoes metaplasia to SSQE
Where on the cervix does HPV infection occur?
cervical transformation zone
