Screening forCervical Cancer

byVisual Inspection Techniques

Dr Aruna BatraVMMC & SJH

Cervical Cancer- Facts

• A significant public health problem• 2nd commonest cancer in ώ worldwide• Annually 3,70,000 new cases of cervical

cancer, 80% in developing countries• Leading cause of death in developing countries,

often killing women at young ages

Cervical Cancer- Facts

• Cause: virtually all cases of cervical cancer are caused by persistent cervical infection with some types of Human Papilloma Virus (STI)

• Develops slowly, has a detectable and treatable precancerous stage

• Preventable disease

Cervical Cancer- Why preventable?

Easy accessibility of Cx & TZ

Natural History of Cervical Cancer

HPV-related Changes

Normal Cervix

Low-Grade SIL

High-Grade SIL

Invasive Cancer

HPV Infection

CofactorsHigh-Risk HPV

About 60% regress within 2-3 yrs

15% progress êin 3-4 yrs

30 - 70% progress êin 10 yrs

Cervical Cancer- Risk Factors

• Early age at marriage• Multiple sexual partners• Sexually transmitted infections• Poor socio-economic status• Smoking• Immunological factors

Prevention of Cervical Cancer

• Primary prevention:– Education to ↓ high risk sexual behaviour– Measures to avoid exposure to HPV & STIs

• Secondary prevention: – Detection & Treatment of precancerous lesions before they

progress to cervical cancer

Cervical Cancer Screening

• Papanicolou smear (cytology)• Visual Inspection techniques• Colposcopy, Cervicography• Molecular (HPV DNA) tests

Methods available

Limitations of Pap Smears for National Screening Programs

• Primary screening is repetitive, labour intensive, time consuming

• Subject to errors of interpretation • Sensitivity 60-70% • Complex logistics, advanced

training, good program implementation required

Limitations of Pap Smears for National Screening Programs

• Pap Smear as a screening methods may not be appropriate or adequate for many low-resource settings

• Even in large cities, quality Pap smears possible but require ongoing supervision, refresher training & continued supplies.

Cytology is not viable as a nationally accessible screening method in many developing countries

Visual Inspection Techniques* Unaided Visual Inspection* Visual inspection with acetic acid (VIA)* Visual inspection with acetic acid and

magnification (VIAM) * Visual inspection with Lugol’s Iodine (VILI)

Unaided Visual Inspection of Cervix

- Dx at stage III & IV ↓from 85% to 55%

- Dx at stage I & II: ↑ from 15% to 45%

Kerala Study 1977-87

Unaided Visual Inspection of Cervix

- 60% of Early disease could be identified - 11% were false positive- Only 15-20% of pre-cancerous lesions

could be detected

Singh V et al 1992

Good for Clinical Down stagingMisses Precancerous lesions

Visual inspection with acetic acid VIA

• Looking at the cervix to detect abnormalities after applying acetic acid

• Acetic acid is used to enhance and “mark” the aceto-white change of a pre-cancerous lesion or actual cancer

VIA- Basis

• Produced due to osmolar changes after acetic acid application, causing water of the cell to leave

• Collapse of the cell membrane around the abnormal and enlarged nucleus

• Altered lesion appears white due to reflection of the incidental light

VIA positive

Dysplastic lesion HPV lesion

VIA Negative

Normal Cervix

VIAM (Visual Inspection with Acetic Acid Using Magnification)

• VIAM is visualization of cervix after application of acetic acid using low power magnification (2.5x to 4x)

Magnascope (4X)

VILIPositive Negative

Normal squamous epithelium Columnar epithelium

Comparison of Screening Methods

Method Sensitivity (%) Specificity (%)

Cytology 45-85 80-98

VIA 60-90 66-96

HPV DNA 65-95 70-96

NEJM Nov17,2005

Screening Costs

Ca Cx prevention in Thailand: Single visit: VIA & Cryosurgery

• 5999 women tested by VIA-13.3% VIA + counseled for immediate Cryo- Accepted by 98.5%- Minor side effects: 2.2%, Major Cp: nil- 83.2% came for follow up, > 95% satisfied

RTCOG: Lancet 2003; 361: 814-820

Safe, acceptable, feasible

Visual Inspection Techniques in Low resource setting

• Noninvasive, easy to perform, inexpensive• All requirements are available locally• Can be performed by all levels of

healthcare workers, in almost any setting• Results are available immediately • Initial treatment can be provided at the

time of the examination

RCH program can act as a powerful tool in preventing Cervical cancer:

* Creating Awareness * Using Simple Screening methods

Conclusion