Page 67 - Screening for Cervical Cancer: Systematic Evidence Review

Chapter III. Results

the laboratory facility. At the University of North Carolina Healthcare System, the Hybrid

Capture II test kit cost $43 in February 2001. The clinical laboratory fees were $125 for Hybrid

Capture II testing and $160 for consensus PCR at the same time. As any other diagnostic

modality, increased demand should eventually increase capacity, in part through competition,

and lower costs. These market forces are not yet at work, and costs have not converged or

declined.

For cost modeling purposes this uncertainty about the expense of the test can easily be

handled by varying the model estimates of test cost. Adequate estimates of the cost of primary

care office-based cervical cancer screening and resulting evaluation and treatment relevant to the

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US health care system are available. However, the remaining parameters required for cost-

effectiveness analysis hinder such estimates. Factors such as repeatability of HPV test results,

incidence and types of HPV by age category, rates of progression and regression of HPV, and

sensitivity and specificity for predicting outcomes over varied intervals of time are inadequately

defined for using HPV tests in screening.

No recent literature specific to the United States is available to model and compare

effectiveness or costs of screening or triage uses of HPV testing that have been proposed. The

most complete contemporary model to date, constructed based on the United Kingdom screening

system, considered adding HPV to Pap testing, replacing Pap testing with HPV testing, and

adding HPV testing to surveillance of low-grade lesions versus continuing conventional

surveillance. The authors concluded: “The uncertainty, as expressed by the differences between

models, is so large, the results are inconclusive. Adding HPV testing to cervical cancer

screening may or may not improve the (cost) effectiveness of screening. There are relatively few

longitudinal HPV screening studies with enough time lapse between measurement points to

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