HPV testing: Indications of a benefit in primary screening

Studies currently available provide indications and a "hint” that precursors of cervical cancer can be detected and treated earlier, and consequently tumours occur less often, in women who underwent testing for human papillomavirus (HPV). In this context, an HPV test can be used alone or in addition to a Papanicolaou test (Pap smear). However, both screening procedures also carry a risk of harm in the form of unnecessary treatments after testing (over-treatment). This is the result of a final report published by the German Institute for Quality and Efficiency in Health Care (IQWiG) on 24th of January 2012.

HPV testing is not reimbursed by SHI funds

In screening for cervical cancer, the German statutory health insurance (SHI) funds currently offer an annual (cytologic) examination of mucosal cells from a smear taken from the neck of the womb (cervix). This test is called a Pap smear. Since it became known that infection with HPV is the main risk factor for developing cervical cancer, experts have been discussing whether HPV testing is also a suitable screening method or is even superior to a cytologic test.

The SHI funds currently only reimburse HPV testing in exceptional cases, for example, in cases where the result of a Pap smear is unclear. The Federal Joint Committee (G-BA) therefore commissioned IQWiG to assess the benefit of HPV testing in primary screening and also to compare different screening strategies with each other.

Lower rates of cancers and their precursors are independent outcome criteria

Cancer screening is usually assessed by determining whether this procedure demonstrably contributes to the prevention of cancer-related deaths. However, in cervical cancer the fact whether or not fully developed (invasive) tumours occur less often can also be a criterion for a screening benefit. Similar to the case of colon cancer, screening for cervical cancer aims to detect and treat cellular changes (dysplasia) from which a cancerous tumour could develop, as treatment of such (advanced) precursors of cancer is far less burdensome for patients than later treatment of a tumour.

Studies with a total of 235,613 participants included

IQWiG searched for studies comparing primary screening strategies for cervical cancer based on different screening tests: a strategy including HPV testing alone or in combination with cytology-based testing and a strategy including cytology-based testing alone.

Six randomized controlled trials conducted in the United Kingdom, Finland, Sweden, the Netherlands, and Italy were included in the assessment. A total of 235,613 women had been recruited for the studies in order to be examined for precursors of invasive cervical cancer in at least two screening rounds with an interval of at least three years. However, all of these studies were susceptible to bias, which limits their informative value.