gms | German Medical Science

Introduction: Compared to cytology, HPV testing has the potential to improve the effectiveness by reducing cervical cancer incidence due to improved early detection and treatment and a higher risk of overdiagnosis and overtreatment of irrelevant lesions. However, despite the evidence of a benefit in reducing cervical cancer, the benefit-harm relation could not be evaluated from clinical trials, yet [1]. This is a typical example for a situation in which clinical trials should be complemented by decision-analytic modelling to aid decision making under uncertainty [2]. We performed a clinical decision analysis evaluating and contrasting the benefits and harms of different strategies for HPV-based primary cervical cancer screening in the German health care context.

Methods: A previously validated and published Markov model [3] for the German health care context was used to analyze the trade-off between benefits and harms of different screening strategies differing by length of screening interval and test algorithms including HPV testing alone or in combination with cytology or with cytological triage for HPV-positive women. We used published German clinical and epidemiological data as well as test accuracy data from international meta-analyses. Predicted outcomes included reduction in cervical cancer cases (CC) and deaths and unnecessary treatment (defined as invasive therapy of ≤ CIN 2).

Results: Overall, HPV-based screening was more effective than cytology alone, with 71%–97% reduction in CC compared to 53%-80% for cytology (depending on screening intervals). The incremental gain in effectiveness with HPV screening compared to cytology was higher with extended screening intervals. Compared to annual cytology, which is currently the recommended standard in Germany, biennial HPV screening was similarly effective (1% lower CC reduction) but reduced unnecessary treatment by 5–37 % (depending on test and follow-up algorithm). In contrast, annual HPV primary screening compared to cytology alone reduced CC by an additional 5 %, but increased unnecessary treatments by 19%.

Conclusion: Based on our decision model analyses, HPV-based cervical cancer screening is more effective than cytology alone, but has a higher risk of overtreatment when used in annual screening. In the German health care context, biennial HPV screening for women aged 30 yrs and older is similarly effective as annual cytology alone, but with significantly reduced unnecessary treatments.