II. Efficacy: Pap Smear Screening for Cervical Cancer

  1. USPSTF Strength of Recommendation: A
  2. False negative Pap Smears
    1. Importance
      1. Accounts for 30% of U.S. Cervical Cancer cases/year
      2. Accounts for 3,700 Cervical Cancer cases/year
    2. Causes
      1. Incomplete transformation zone sampling
      2. Poorly prepared slide (e.g. drying artifact)
      3. Cytotechnologist failure to detect abnormality
        1. Now limited to 100 slides per day for review
        2. Now 10% of "normal" slides re-screened
  3. Adjunctive methods to decrease False Negative Rate
    1. General
      1. Adjuncts listed below do not appear cost effective
      2. Adjuncts identify more LGSIL lesions
    2. Liquid-Based/Thin-Layer Preparation
      1. Improves cell sample and fixation
      2. Commercial Tests
        1. Thin Prep
        2. AutoCyte Prep (TriPath)
    3. Computer-Assisted Screening
      1. AutoPap: Scores slide on likeliood of abnormality
      2. AutoCyte: Presents cell images to cytopathologist
    4. HPV Testing
      1. Hybrid Capture II detects 13 high risk HPV types
      2. May triage ASCUS and non-correlating Colposcopy
      3. No cost effective indications currently
  4. References
    1. Nuovo (2001) Am Fam Physician 64:780-6 [PubMed]

III. Management: Extremely Low Risk Patients - Pap Smear not necessary

  1. Virginal patients
  2. Hysterectomy for benign disease (see below)
    1. Recent studies suggest no further Pap Smears needed
  3. Age 65-70 or over (AAFP and USPTF recommend age 65)
    1. Two consecutive negative Pap Smears with HPV testing, with most recent test within last 5 years OR
    2. Three normal consecutive Pap Smears and no abnormal Pap Smears in the last 10 years (ACS)

IV. Management: Average Risk Patients

  1. Protocol (varies by ACS, ACOG and USPHS)
    1. Initial screening until age 30 years
      1. Thin Prep Pap Smear cytology without HPV testing once every 3 years for those under 30 years
      2. Do not test HPV with Pap Smear for those under age 30 years (high Prevalence)
    2. Indications to spread out Pap Smear Intervals to every 2-3 years (after age 30)
      1. Age over 30 and
      2. No prior abnormal Pap Smears and
      3. HPV negative (at least one test after age 30 years)
    3. Protocol to spread out Pap Smear Intervals to every 5 years (after age 30)
      1. Average criteria met for women over age 30 years (see above)
      2. Perform HPV screening with thin prep Pap Smear every 5 years
  2. Criteria
    1. Pap Smears start at age 21 years regardless of sexual activity
    2. Sexual activity onset after age 20 years
      1. Start Pap Smears within 3 years of 1st intercourse
      2. Even virginal patient should start Pap Smears at 21
    3. Under age 21 years: pap 3 years after first intercourse
      1. Patients with less than 3 lifetime sexual partners
      2. Patients who consistently use barrier Contraception
      3. No Tobacco abuse
      4. Previously normal Pap Smear
      5. No Sexually Transmitted Disease history

V. Management: High Risk Patients

  1. Protocol
    1. Initially screen twice yearly and then
    2. Subsequently yearly Pap Smear
  2. Criteria
    1. Sexual activity onset before age 20 years
      1. Start Pap Smears within 3 years of 1st intercourse
      2. Screen and prevent Sexually Transmitted Diseases
    2. Patients with three or more lifetime sexual partners
    3. History of HPV or other Sexually Transmitted Disease
    4. Previously abnormal Pap Smear
    5. Tobacco abuse
    6. Immunocompromised patients

VI. Management: After Hysterectomy (with Cervix removed)

  1. General Recommendations for vaginal cytology
    1. ACP recommends no further Pap Smears after Hysterectomy with Cervix removed
    2. No history of abnormal Pap Smear cytology
      1. Consider no further screening after Hysterectomy
      2. Some clinicians recommend screening every 10 years
    3. Prior Pap Smear abnormalities
      1. Initial Vaginal smear 3 years after Hysterectomy
      2. Subsequent vaginal smears every 5 years
    4. Endpoint
      1. See Very low risk patient criteria above
  2. History of CIN 2-3
    1. Annual Pap Smear until 3 consecutive normals
    2. If Pap Smear positive for CIN 2-3
      1. Treat as indicated
      2. Recheck every 4-6 months
  3. References
    1. Piscitelli (1995) Obstet Gynecol 173:424-32 [PubMed]
    2. Pearce (1996) N Engl J Med 335:1559-62 [PubMed]
    3. Noller (1996) N Engl J Med 335:1599-1600 [PubMed]
    4. Videlefsky (2000) J Am Board Fam Pract 13:233-8 [PubMed]

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