What is the Most Efficient Method for Cervical Cancer Screening?
BACKGROUND:
- As part of the evidence report for the new USPSTF recommendations for cervical cancer screening recently released (see ‘Related ObG Topics’ below), a decision analysis using a disease simulation model was constructed
- Kim et al. (JAMA, 2018) modeled the benefits and harms of various cervical cancer screening strategies
METHODS:
- Microsimulation model of a hypothetical cohort of women initiating screening at age 21 years
- The models looked at 19 strategies for cervical cancer screening, including 2 previous guideline-based strategies
- Previous guideline strategy 1: Cytology alone every 3 years from ages 21 to 65 years
- Previous guideline strategy 2: Cytology alone every 3 years from ages 21 to 29 years, with a switch to cytology and hrHPV cotesting every 5 years from ages 30 to 65 years
- Primary HPV testing strategies
- Outcomes assessed risks and benefits
- Harms: Total number of cytology and hrHPV tests (including screening, triage, and surveillance) | Colposcopies | FP screening results
- Benefits: CIN 2 and CIN 3 detected | CIN 3 or worse (CIN 3+) detected (including CIN 3 and cervical cancers detected through screening) | Cervical cancer cases and deaths averted | Life-years gained
- Efficient strategies
- More benefit and less harm than another strategy or
- Lower harm to benefit ratio than a strategy with less harms
RESULTS:
- Compared with no screening, all modeled cervical cancer screening strategies were estimated to result in substantial reductions in cancer cases and deaths and gains in life-years
- The effectiveness of screening across the different strategies was estimated to be similar
- Primary hrHPV-based and alternative cotesting strategies have slightly higher effectiveness and greater harms than current guidelines-based cytology testing
- In all analyses, primary hrHPV testing strategies occurring at 5-year intervals were efficient
- In contrast, strategies involving 3-year hrHPV testing was less efficient with much higher harm/benefit ratios, ranging from 2188 to 3822 colposcopies per life-year gained
- In most analyses, strategies involving cotesting were not efficient
CONCLUSION:
- From modeling, it was estimated that primary hrHPV screening demonstrated a reasonable balance of harms and benefits when performed every 5 years
- The most efficient harm/benefit strategy was converting from cytology to hrHPV at age 30
