1. Screening for Cervical Cancer
Max Brinsmead MB BS PhD
May 2015

2. Cervical Cytology
As a screening test for Ca Cx this test has only ~75% sensitivity
Better at detecting CIN
but then specificity is a problem
Must sample the squamocolumnar junction
More significant if +ve in a high risk individual
Older
Early sex, multiple partners, other STDs
Smoking
HPV infection with high risk subtype
Liquid-based cytology can enhance sensitivity by ≈5%
Start at age 20 or within 3 years first coitus

3. Cytological Terms LGEA = Low grade epithelial abnormality
Replaces the older term mild dysplasia
Mostly due to HPV
Also called low grade squamous intraepithelial lesion or LSIL
HGEA = High grade epithelial abnormality
Replaces the older terms moderate & severe dysplasia
Arises from CIN1 & CIN2 (but these are histological terms)
Also called high grade squamous intraepithelial lesion or HSIL
Both the above have “Possible” variants ie
Possible LGEA = former “nonspecific minor changes”
Possible HGEA = former “Inconclusive” report

4. Colposcopy Limited by need for expert and equipment
Relatively expensive
Subjective
Limited to visible part of the Cx
CIN can be masked by HPV
Of most use in identifying area for biopsy
Better therefore than previous alternative of cone biopsy

5. Histology The gold standard for diagnosis
Only as good as the sample received
(except for cone or LLETZ)
And still somewhat subjective
But accuracy is increased if stains for high risk HPV DNA is used

6. Natural History of CIN Progression 123cancer is not inevitable
CIN % spontaneously regress
CIN 3 – 50% regress or stay the same
Progression time varies
6m to 16 years
But some will have invasive Ca when Pap smear reports only LGEA
Hence the debate about current NH&MRC guidelines

7. HPV Subtyping 90% of Ca Cx is associated with High Risk HPV
Subtypes 16,18,45,31,33,35,52,58 etc
Highly sensitive for the detection of HGEA
Does not require equipment or expertise
Equivocal results can occur
Of most use in the follow up of treated CIN
And those patients with persisting LGEA on Pap smear

8. Treatment Options for CIN
Observation
LGEA
Young women
Obvious HPV infection
Chronic LGEA with Low risk HPV subtype
Targeted destruction
Laser
Diathermy
Cryotherapy
Excision of the Squamocolumnar Junction
LETZ
Cone Biopsy
Hysterectomy

9. Follow up of CIN 90 – 95% will be “cured” forever Pap smears
Repeated until negative
12 monthly for 2 years
Colposcopy
Ideally at lease once 6m after the procedure
HPV High Risk subtyping
Perform 12m and 24m after the procedure
High negative predictive value
Obstetric implications of treated CIN debatable

10. Current NH&MRC Guidelines
Repeat Pap once 12m after the first or if no tests tests for 5 years. Thereafter 2 yearly
Unsatisfactory Pap
Treat as required
Repeat in 3m
Send for colposcopy if 3 consecutive unsatisfactory
For LGEA
If <30 years repeat in 12 months
If >30 refer for colposcopy or repeat in 6m
For HGEA
Send for colposcopy

11. Current NH&MRC Guidelines (2)
For HSIL on colposcopy and biopsy
LLETZ
For HGEA on Pap but colposcopy unsatisfactory
Cone biopsy
LSIL on colposcopy and biopsy
Review in 12m
Return to normal after 2 negative tests 12m apart
Send for colposcopy if 3 consecutive unsatisfactory
Refer all suspected adenomatous abnormalities

12. Prevention of CIN and Genital Warts
Polyvalent vaccines (types 6,11, 16 & 18)
Provide 90 – 100% protection from persistent infection, 16/18-related CIN2-3, adenoCa in situ and Ca Cx
Also protects against genital warts caused by the low risk HPV subtypes 6 & 11
Therapeutic vaccines also under study
Optimal age for immunisation and need for boosters under evaluation
?Male immunisation

13. Counselling a Patient with a Positive Pap Smear
This is not cancer
It is pre cancer
It is the whole point of doing Pap tests i.e. to detect and treat pre cancer so as to prevent it becoming cancer
Just like watching /removing “moles” of the skin
Not all pre cancer becomes cancer
It is a common condition
40 – 50% of ♀ not immunised at some time in their life
STD basis not helpful but may need to be addressed
The Pap test is not diagnostic
Only a well-directed biopsy can be used for Rx decisions

14. Any Questions or Comments?
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