Cervical screening and CIN Flashcards
What age and how often are women screened?
⎫ Sexually active women aged 25-64
⎫ 3 yearly from 25-50 and 5 yearly until 64
What specific group of women require annual smears?
HIV +ve
What % of abnormalities are detected by screening?
95
What Is CIN?
Cervical intra-epithelial neoplasia (CIN) is the pre-invasive phase of cervical cancer
What is CIN 1
affects the lower basal third of cervical epithelium and will regress to normal in 60% within 2 years
What is CIN 2
<2/3 of epithelium
What is CIN 3
> 2/3 of epithelium (up to full thickness)
What HPV strains is CIN associated w ?
16, 18, 31 and 33
What are CIN 2 and 3 at higher risk of ?
developing into invasive squamous carcinoma of the cervix
What is dyskaryosis?
Abnormal cytologic changes of squamous epithelial cells
Explain the process of screening if borderline or mild dyskaryosis is found on a smear
Women w borderline or mild changes are tested for high-risk HPV
If +ve refer to colposcopy
Explain the process of screening if mod-severe dyskaryosis is found on a smear
Colposcopy regardless of HPV status
How does dyskaryosis relate to CIN?
Degree of dyskaryosis approximates to the severity of CIN
What are risk factors for CIN?
Persistent high risk HPV infection Multiple partners (increased exposure) Smoking Immunocompromise OCP (probs due to reduced use of barrier contraceptives)
What is the first stage in management of CIN?
Colposcopy
Explain what happens in colposcopy
→ Woman in lithotomy position w speculum inserted
Cervix visualised, transformation zone identified and painted w 5% acetic acid
Lugol’s iodine is then
used
Punch biopsy taken
What is acetic acid used for?
it is preferentially taken up by neoplastic cells
What is lugols iodine used for?
not take up by neoplastic cells
How are abnormal areas identified on colposcopy?
they appear white by the acetic acid
When is LLETZ offereD?
if high grade CIN (>1)
What is LLETZ
Large loop excision of the transformation zone
Is performed under local anaesthetic w loop diathermy
What are the complications of LLETZ
o Haemorrhage o Infection o Vaso-vagal sx o Anxiety o Cervical stenosis o Premature delivery
What is the required follow up for LLETZ
smear at 6m w high risk HPV testing
What is CGIN
cervical glandular intraepithelial neoplasia
What is CGIN associated w
high risk HPV
Why is CGIN difficult to manage?
endocervical epithelium extends into the cervical canal and is therefore not completely visible at colposcopy
What is the treatment of CGIN
cylindrical LLETZ, cone biopsy or hysterectomy
When is the HPV vaccination offered?
12yrs
What subtypes is HPV aimed at
6,11,16 and 18
When doesn’t the HPV vaccination offer protection?
once the HPV infection has occurred
