Budget impact analysis of cervical cancer screening in Portugal: comparison of cytology and primary HPV screening strategies.

BACKGROUND: Primary Human Papilloma Virus (HPV) testing is the currently recommended cervical cancer (CxCa) screening strategy by the Portuguese Society of Gynecology (SPG) clinical consensus. However, primary HPV testing has not yet been adopted by the Portuguese organized screening programs. This modelling study compares clinical benefits and costs of replacing the current practice, namely cytology with ASCUS HPV triage, with 2 comparative strategies: 1) HPV (pooled) test with cytology triage, or 2) HPV test with 16/18 genotyping and cytology triage, in organized CxCa screenings in Portugal. METHODS: A budget impact model compares screening performance, clinical outcomes and budget impact of the 3 screening strategies. A hypothetical cohort of 2,078,039 Portuguese women aged 25-64 years old women is followed for two screening cycles. Screening intervals are 3 years for cytology and 5 years for the HPV strategies. Model inputs include epidemiological, test performance and medical cost data. Clinical impacts are assessed with the numbers of CIN2-3 and CxCa detected. Annual costs, budget impact and cost of detecting one CIN2+ were calculated from a public healthcare payer's perspective. RESULTS: HPV testing with HPV16/18 genotyping and cytology triage (comparator 2) shows the best clinical outcomes at the same cost as comparator 1 and is the most cost-effective CxCa screening strategy in the Portuguese context. Compared to screening with cytology, it would reduce annual CxCa incidence from 9.3 to 5.3 per 100,000, and CxCa mortality from 2.7 to 1.1 per 100,000. Further, it generates substantial cost savings by reducing the annual costs by €9.16 million (- 24%). The cost of detecting CIN2+ decreases from the current €15,845 to €12,795. On the other hand, HPV (pooled) test with cytology triage (comparator 1) reduces annual incidence of CxCa to 6.9 per 100,000 and CxCa mortality to 1.6 per 100,000, with a cost of €13,227 per CIN2+ detected with annual savings of €9.36 million (- 24%). The savings are mainly caused by increasing the length of routine screening intervals from three to five years. CONCLUSION: The results support current clinical recommendations to replace cytology with HPV with 16/18 genotyping with cytology triage as screening algorithm.