A 58-year-old woman with no prior abnormal Pap smears had an ASC-US (Atypical Squamous Cells of Undetermined Significance) result and a negative high-risk HPV test; when should she be rescreened?

Rescreening Recommendation for ASC-US with Negative HPV

This 58-year-old woman should return for repeat cervical cancer screening with co-testing (Pap and HPV) in 3 years. 1

Rationale Based on Current Guidelines

The American Cancer Society (ACS), American Society for Colposcopy and Cervical Pathology (ASCCP), and American Society for Clinical Pathology (ASCP) joint guidelines explicitly state that women with an HPV-negative ASC-US result should return for screening in 3 years. 1

Why 3 Years Instead of 5 Years?

Initially, the 2012 screening guidelines suggested that HPV-negative ASC-US could be managed with 5-year follow-up, similar to negative co-testing. However, updated data from Kaiser Permanente Northern California (KPNC) involving over 1 million women demonstrated that the risk after HPV-negative ASC-US is higher than after negative co-testing. 1

Specifically:

• The 5-year risk of CIN3+ after HPV-negative ASC-US (0.48%) is closer to the risk after a negative Pap test alone (0.31%) than after negative co-testing (0.11%) 2
• The cancer risk after HPV-negative ASC-US (0.043%) is also intermediate between negative Pap alone (0.031%) and negative co-testing (0.014%) 2
• Following the principle of "equal management for equal risks," the ASCCP consensus conference changed the recommendation from 5-year to 3-year follow-up 1

Screening Method at Follow-Up

For this 58-year-old woman (age 30-65 years), the preferred screening approach at the 3-year follow-up is co-testing with both HPV and cytology every 5 years thereafter if results are normal. 1 Alternatively, cytology alone every 3 years is acceptable if co-testing is not available. 1

Important Considerations for This Patient's Age

Implications for Screening Cessation

HPV-negative ASC-US results are NOT sufficiently reassuring to allow women to stop screening at age 65 years. 1 KPNC data showed that although dysplasia risk is low after HPV-negative ASC-US in women approaching age 65, cancer risk is disproportionately high in this age group. 1

Therefore, if this woman reaches age 65 with only this HPV-negative ASC-US result:

• She should be retested in 3 years 1
• She must continue surveillance until she has 2 consecutive negative co-tests OR 3 consecutive negative Pap tests before discontinuing screening 1
• An HPV-negative ASC-US result should NOT be regarded as negative for the purpose of discontinuing screening at age 65 1

What NOT to Do

Colposcopy is Not Indicated

Immediate colposcopy is not recommended because the current risk for CIN3+ after ASC-US with negative HPV is below the agreed threshold for colposcopy. 1 The absolute risk of CIN3+ is very low (less than 2% overall, and less than 1% in the most robust studies). 1

HPV 16/18 Genotyping is Not Useful

HPV 16/18 genotyping should not be used to further assess women with ASC-US Pap test results because results do not alter management—all ASC-US patients with negative HPV should be managed the same way regardless of specific genotype information. 1

Do Not Return to 5-Year Intervals Yet

Although the risk is low, it is not low enough to justify the 5-year interval used for negative co-testing. The 3-year interval provides appropriate surveillance given the intermediate risk level. 1, 2

Common Pitfalls to Avoid

• Do not treat this as equivalent to negative co-testing: While the absolute risk is low, it is measurably higher than true negative co-testing and requires more frequent surveillance 1, 2
• Do not allow early exit from screening: This result cannot be used as one of the negative screening tests needed to discontinue screening at age 65 1
• Do not perform repeat testing earlier than 3 years: This would lead to unnecessary procedures without improving outcomes 1