The document discusses the Pap smear screening test for cervical cancer. It describes how Pap smears have reduced cervical cancer incidence by 80% and mortality by 70% by allowing for treatment of pre-cancerous lesions. Screening should begin within 3 years of becoming sexually active and can typically decrease in frequency to every 2-3 years after 3 normal annual tests. Screening may stop at age 70 after recent negative tests or hysterectomy. The document outlines the anatomy of the cervix and squamo-columnar junction, techniques for Pap smear collection, abnormal findings, screening guidelines, and accuracy of Pap smears.

2. PAP smear: named after
Dr. George Papanicolaou (1883-1962)
Vaginal smears from guinea pigs (1917)
Women (1920)
Hormonal
cycles
Pathological conditions (1928)

3. Cytologic screening for cervical cancer
Usefulness of pap smear in the screening programme
for cancer cervix is shown by the following:
Long latent period of 10-15 years between CIN and
invasive cancer allows adequate treatment of CIN
and prevention of invasive cancer
Proved successful in reducing the incidence of
invasive cancer by 80% and the mortality by 70%

4. When to screen
Start within 3 years of onset of sexual activity or by age
of 21, whichever is first.
High risk factors for cervical dysplasia:
Early onset of sexual activity
Multiple sexual partners
Smoking habits
Oral contraceptives
HPV and HIV positive women

5. Screening frequency
Yearly until three consecutive normal pap smears, then
may decrease frequency to every 2-3 years
Annual screening for high-risk women is highly
recommend.

6. When to stop routine screening
Age 70 and “adequate recent screening”
Three consecutive negative pap smears
No abnormal pap smears in last 10 years
Hysterectomy for benign lesion

8. Original Squamous Epithelium
Vagina and outer ectocervix
4 cell layers
Well-glycogenated (pink) unless atrophic

9. Columnar Epithelium
Upper and middle endo-cervical canal
Single layer of columnar cells arranged in
folds
Mucin producing (not true glands)

10. Squamous Metaplasia
Central ectocervix and lower endocervical canal
Replacement of columnar cells by squamous epithelium
Progressive and stimulated by
Acidic environment with onset of puberty
Estrogen causing eversion of endocervix

11. Original Squamo-columnar Junction
Placement determined between 18-20 weeks gestation
Most often found on ectocervix
Can be found in vagina or vaginal fornices
Less apparent over time with maturation of
epithelium

12. “New” Squamo-columnar Junction
Border between squamous epithelium and columnar
epithelium
Found on ecto-cervix or in endo-cervical canal
Majority of cervical cancers and precursor lesions
arise in immature squamous metaplasia, i.e. the
leading edge of the squamo-columnar junction

13. Transformation Zone
Zone between original squamo-columnar junction and
the “new” squamo-columnar junction
Nabothian cysts visually identify the transformation
zone if present

14. Squamous Epithelium

15. Parabasal Cells

16. Intermediate Cells

17. Superficial
Cells

18. Endocervix

19. Endocervical Cells

20. Technique
Visualize entire cervix if possible
Carefully remove any obscuring discharge
Sample ectocervix first with spatula
Sample endocervix with gentle cytobrush
rotation
Apply material uniformly to slide
Fix rapidly with spray or liquid fixative

23. Classification of Pap smear
Class
Reagen(WHO)
Ruchart
Bethesda
Class 1
negative
negative
Within normal
Class 2
inflammation
Class 3
Mild dysplasia
CIN-l (HPV)
LSIL (HPV)
Class 4
Mod dysplasia
Seve dysplasia
Carcinoma in situ
CIN-ll
CIN-lll
HSIL
Class 5
Invasive cancer
Invasive cancer
Invasive cancer
------
ASCUS

24. “Normal” Pap Smear
Negative for intraepithelial lesion or malignancy
Other non-neoplastic findings
Reactive cellular changes
Glandular cells status post hysterectomy
Atrophy
Other
Endometrial cells (women ≥ 40 yrs)

25. Normal smear

26. Epithelial Cell Abnormalities:
Squamous
Atypical squamous cells
ASC-US: undetermined significance
ASC-H: cannot exclude HSIL
LSIL: low grade (CIN 1)
HSIL: high grade (CIN 2 - 3)
Squamous cell carcinoma

27. SIL and CIN

28. Various types of cervical lesions as seen on Pap smears:
CIN I.

29. Various types of cervical lesions as seen on Pap smears:
CIN Il

30. Various types of cervical lesions as seen on Pap smears:
CIN lll

31. Various types of cervical lesions as seen on Pap smears:
invasive squamous cell carcinoma.

32. Epithelial Cell Abnormalities:
Glandular
Atypical glandular cells,specify site of origin,if
possible
Atypical glandular cells - favor neoplastia
Endocervical adenocarcinoma in situ
Adenocarcinoma

33. Various types of cervical lesions as seen on Pap smears:
adenocarcinoma

34. Accuracy
Single pap smear-diagnostic sensitivity 60%
False negative results upto25% due to:
too scanty,too thick,too bloody,poorly stained
smear
misinterpretation by the cytologist
• In the presence of infection repeat cytology has to be
done after the infection is controlled
Abnormal cytology is an indication of colposcopic
evaluation and directed biopsy