Cervical cancer & CIN (incl. colposcopy, LLETZ) Flashcards
What is the most important factor in the development of cervical cancer?
Human papillomavirus (HPV), particularly serotypes 16,18 & 33
When does cervical cancer present?
At least 50% occur in women <45yrs
Most common in 25-29 year olds
What is the most common type of cervical cancer? What is the second?
- squamous cell cancer (80%)
- adenocarcinoma (20%)
How does cervical cancer present?
Asymptomatic - may be detected during routine cervical cancer screening
Symptomatic -
- abnormal vaginal bleeding: postcoital, intermenstrual or postmenopausal bleeding
- vaginal discharge
What are the risk factors for development of cervical cancer?
- HPV 16, 18 and 33
- smoking
- HIV
- early first intercourse, many sexual partners
- high parity
- lower socioeconomic status
- COCP (previously debated but now proven)
What is the pathophysiology of HPV in cervical cancer?
HPV 16 & 18 produces the oncogenes E6 and E7 genes respectively
- E6 inhibits the p53 tumour suppressor gene
- E7 inhibits RB suppressor gene
Which HPV strains cause cervical cancer vs genital warts?
6 & 11 - causes genital warts
16 & 18 - linked to a variety of cancers, most commonly cervical cancer - HPV infection is linked to 99.7% of cervical cancers
What other cancers is HPV infection linked to?
- >99.7% of cervical cancers
- ~85% of anal cancers
- ~50% of vulval and vaginal cancers
- ~20-30% of mouth and throat cancers
How many deaths does UK screening for cervical cancer prevent?
Prevents 1,000-4,000 deaths per year
What is the aim of cervical cancer screening?
To detect pre-malignant changes rather than to detect cancer
What is a major disadvantage of the cervical screening programme?
Cervical adenocarcinomas, which account for around 15% of cases, are frequently undetected by screening
Who is screened for cervical cancer? How often?
Smears are offered to all women between ages of 25-64 years old:
- 25-49 years: 3-yearly screening
- 50-64 years: 5-yearly screening
cervical screening cannot be offered to women over 64 (unlike breast screening, where patients can self refer once past screening age)
Can patients aged 65 self-refer for cervial cancer screening?
No - cervical screening cannot be offered to women over 64 (unlike breast screening, where patients can self refer once past screening age)
If a women is pregnant, can cervical cancer screening still be carried out?
Cervical screening in pregnancy is usually delayed until 3 months post-partum unless missed screening or previous abnormal smears.
Do lesbians or women who are not sexually active need to have cervical cancer screening?
Women who have never been sexually active have very low risk of developing cervical cancer therefore they may wish to opt-out of screening
Lesbian women should still take up screening as HPV can be transmitted by other types of sex and from partners who previously had heterosexual relationships. Unfortunately uptake is x10 worse in lesbian patients.
What type of smear is used nowadays?
Liquid-based cytology (LBC) is more commonly used than Papanicolaou (Pap) smears
Rather than smearing the sample onto a slide the sample is either rinsed into the preservative fluid or the brush head is simply removed into the sample bottle containing the preservative fluid.
What is the advantage of LBC over Pap smears?
- reduced rate of inadequate smears
- increased sensitivity and specificity
In relation to the mestrual cycle, when is the best time to take the sample?
Mid-cycle - although there is limited evidence to support this.
“The NHS has now moved to an HPV first system” - what does this mean in relation to cervical cancer screening?
i.e. a sample is tested for high-risk strains of HPV (hrHPV) first and cytological examination is only performed if this is positive.
What is the management of sample negative for hrHPV?
Return to normal recall
Except if:
- Test of cure pathway for CIN1-3 - 6 month recall
- Untreated CIN1
- Incompletely excised CGIN (cervical glandular intraepithelial neoplasia)/ stratified mucin producing intraepithelial lesion (SMILE)
What is the management of a positive hrHPV patient?
–> cytology