The planning of cervical cancer screening programmes in eastern Europe: is viral testing a suitable alternative to smear testing?

Cost-effectiveness of primarily human papillomavirus–based cervical cancer screening in settings with currently established Pap screening: A systematic review commissioned by the German Federal Ministry of Health

Objectives:The aim of this study was to summarize the current evidence for the cost-effectiveness of primarily human papillomavirus (HPV) -based cervical cancer screening in settings with already established Papanicolaou test (Pap) programs. Emphasis was placed on the German situation with annual Pap screening.

Methods:Medical, economic, and health technology assessment (HTA) databases were systematically searched for cost-effectiveness studies comparing HPV to Pap screening. Study data were extracted, standardized, and summarized in cost-effectiveness plots contrasting HPV strategies to Pap screening with 1-, 2-, 3-, and 5-years interval. For each Pap setting, the likelihood of cost-effective HPV screening was assessed depending on willingness-to-pay.

Results:We reviewed twelve decision-analytic cost-effectiveness models. Study results showed wide variation due to methodical heterogeneity. Data synthesis revealed that the cost-effectiveness of HPV screening depends on the interval of the established Pap screening strategy. In comparison with Pap screening every 2 years, only 25 percent of the HPV-based screening strategies were cost-effective. However, in comparison with Pap screening every 1, 3, or 5 years, 83 percent, 55 percent, and 92 percent of HPV screening strategies were cost-effective, respectively. Results for settings with annual Pap screening are based on models assuming 100 percent screening coverage.

Conclusions:The introduction of HPV-based screening programs is cost-effective if the screening interval of the established Pap program exceeds 2 years. In settings with biennial Pap screening, introduction of HPV-based screening is unlikely to be cost-effective. Results also suggest cost-effectiveness of HPV-based screening in settings with annual Pap screening; however, this finding should be confirmed under realistic screening adherence assumptions.

A public health approach to cervical cancer control: considerations of screening and vaccination strategies

Cervical cancer remains a leading cause of cancer death among women living in low-resource settings. In the last 3 decades, cytologic screening has -in theory -been available and yet more than 6 million women have died of this preventable disease. The necessary resources, infrastructure, and technological expertise, together with the need for repeated screenings at regular intervals, make cytologic screening difficult to implement in poor countries. As noncytologic approaches for the detection of HPV, simple visual screening methods for anogenital lesions caused by HPV, and the availability of an HPV-16/18 vaccine will enhance the linkage between screening and treatment, multiple factors will need to be considered when designing new, or modifying existing prevention strategies. Countryspecific decisions regarding the best strategy for cervical cancer control will need to rely on data from many sources and take into account complex epidemiologic, economic, social, political, and cultural factors, and be made despite uncertainty and incomplete information. A rigorous decision analytic approach using computerbased modeling methods enables linkage of the knowledge gained from empirical studies to real-world situations. This chapter provides an introduction to these methods, reviews lessons learned from cost-effectiveness analyses of cervical cancer screening in developed and developing countries, and emphasizes important qualitative themes to consider in designing cervical cancer prevention policies.

Estimating the cost of cervical cancer screening in five developing countries

BACKGROUND

Cost-effectiveness analyses (CEAs) can provide useful information to policymakers concerned with the broad allocation of resources as well as to local decision makers choosing between different options for reducing the burden from a single disease. For the latter, it is important to use country-specific data when possible and to represent cost differences between countries that might make one strategy more or less attractive than another strategy locally. As part of a CEA of cervical cancer screening in five developing countries, we supplemented limited primary cost data by developing other estimation techniques for direct medical and non-medical costs associated with alternative screening approaches using one of three initial screening tests: simple visual screening, HPV DNA testing, and cervical cytology. Here, we report estimation methods and results for three cost areas in which data were lacking.

METHODS

To supplement direct medical costs, including staff, supplies, and equipment depreciation using country-specific data, we used alternative techniques to quantify cervical cytology and HPV DNA laboratory sample processing costs. We used a detailed quantity and price approach whose face validity was compared to an adaptation of a US laboratory estimation methodology. This methodology was also used to project annual sample processing capacities for each laboratory type. The cost of sample transport from the clinic to the laboratory was estimated using spatial models. A plausible range of the cost of patient time spent seeking and receiving screening was estimated using only formal sector employment and wages as well as using both formal and informal sector participation and country-specific minimum wages. Data sources included primary data from country-specific studies, international databases, international prices, and expert opinion. Costs were standardized to year 2000 international dollars using inflation adjustment and purchasing power parity.

RESULTS

Cervical cytology laboratory processing costs were I$1.57-3.37 using the quantity and price method compared to I$1.58-3.02 from the face validation method. HPV DNA processing costs were I$6.07-6.59. Rural laboratory transport costs for cytology were I$0.12-0.64 and I$0.14-0.74 for HPV DNA laboratories. Under assumptions of lower resource efficiency, these estimates increased to I$0.42-0.83 and I$0.54-1.06. Estimates of the value of an hour of patient time using only formal sector participation were I$0.07-4.16, increasing to I$0.30-4.80 when informal and unpaid labor was also included. The value of patient time for traveling, waiting, and attending a screening visit was I$0.68-17.74. With the total cost of screening for cytology and HPV DNA testing ranging from I$4.85-40.54 and I$11.30-48.77 respectively, the cost of the laboratory transport, processing, and patient time accounted for 26-66% and 33-65% of the total costs. From a payer perspective, laboratory transport and processing accounted for 18-48% and 25-60% of total direct medical costs of I$4.11-19.96 and I$10.57-28.18 respectively.

CONCLUSION

Cost estimates of laboratory processing, sample transport, and patient time account for a significant proportion of total cervical cancer screening costs in five developing countries and provide important inputs for CEAs of alternative screening modalities.

Chapter 19: Cost-effectiveness of cervical cancer screening

In the last two decades, computer-based models of cervical cancer screening have been used to evaluate the cost-effectiveness of different secondary prevention policies. Analyses in countries with existing screening programs have focused on identifying the optimal screening interval, ages for starting and stopping screening, and consideration of enhancements to conventional cytology, such as human papillomavirus (HPV)-DNA testing as a triage for equivocal results or as a primary screening test for women over the age of 30. Analyses in resource-poor settings with infrequent or no screening have focused on strategies that enhance the linkage between screening and treatment, consider noncytologic alternatives such as HPV-DNA testing, and target women between the ages of 35 and 45 for screening one, two, or three times per lifetime. Despite differences in methods and assumptions, this paper identifies the qualitative themes that are consistent among studies, and highlights important methodological challenges and high-priority areas for further work.

Cost-effectiveness of human papillomavirus DNA testing in the United Kingdom, The Netherlands, France, and Italy

BACKGROUND

European countries with established cytology-based screening programs for cervical cancer will soon face decisions about whether to incorporate human papillomavirus (HPV) DNA testing and what strategies will be most cost-effective. We assessed the cost-effectiveness of incorporating HPV DNA testing into existing cervical cancer screening programs in the United Kingdom, The Netherlands, France, and Italy.

METHODS

We created a computer-based model of the natural history of cervical carcinogenesis for each using country-specific data on cervical cancer risk and compared each country's current screening policy with two new strategies: 1) cytology throughout a woman's lifetime, using HPV DNA testing as a triage strategy for equivocal cytology results ("HPV triage"), as well as 2) cytology until age 30 years and HPV DNA testing in combination with cytology in women more than 30 years of age ("combination testing"). Outcomes included reduction in lifetime cervical cancer risk, increase in life expectancy, lifetime costs, and incremental cost-effectiveness ratios, expressed as cost per year of life saved. We explored alternative protocols and conducted sensitivity analysis on key parameters of the model over a relevant range of values to identify the most cost-effective options for each country.

RESULTS

Both HPV DNA testing strategies, HPV triage and combination testing, were more effective than each country's status quo screening policy. Incremental cost-effectiveness ratios for HPV triage were less than $13,000 per year of life saved, whereas those for combination testing ranged from $9800 to $75,900 per year of life saved, depending on screening interval. We identified options that would be very cost-effective (i.e., cost-effectiveness ratio less than the gross domestic product per capita) in each of the four countries.

CONCLUSIONS

HPV DNA testing has the potential to improve health benefits at a reasonable cost compared with current screening policies in four European countries.