AIM: For cost-effectiveness, mammo guidelines should be rooted in risk
Guidelines for breast screening mammography should take into account patient-specific risk factors to garner more cost-effective screening, with payors standing to gain from suggesting markedly less frequent screening for lower-risk women, argued the authors of a study published July 4 in the Annals of Internal Medicine.

With demonstrated mortality reductions ranging between 15 and 20 percent, mammography is recommended either annually or biennially to women after reaching 40 or 50 years of age. Although considered cost-effective for women at average risk, screening guidelines do not take into account individual patients’ risks, such as breast density, history of biopsy and family history of breast cancer, explained John T. Schousboe, MD, PhD, of the Park Nicollet Institute in Minneapolis, and colleagues.

From the perspective of a payor, Schousboe and co-authors sought to assess the cost-effectiveness of screening for women at different frequencies, ages and risk-levels. The authors performed the cost-effectiveness analysis based on two thresholds, one quality-adjusted life-year (QALY) gained per either $100,000 or $50,000 in costs. Data were pulled from the Breast Cancer Surveillance Consortium and the Surveillance, Epidemiology and End Results (SEER) programs.

The researchers found that the most cost-effective frequency of mammography depended considerably on a woman’s age, breast density, family history of breast cancer and history of breast biopsy. Meanwhile, Schousboe and co-authors argued that all women should undergo an initial mammography at 40 years in order to better determine their level of risk and a personalized screening interval.

Using a threshold of $100,000 per QALY gained, biennial screening of women aged 40 to 49 would be cost-effective if they fell into BI-RADS category 3 or 4 for breast density or if this age group had both a previous breast biopsy and a family history of breast cancer. Among women 50 to 59 years of age, biennial screening would be cost-effective for women with BI-RADS category 2, 3 or 4 breast density, as well as for women in category 1 who also had a previous breast biopsy and a family history of breast cancer.

Among the 50 to 59 group with BI-RADS category 1 and no history of biopsy or family breast cancer, screening only every three to four years would represent a cost-effective regimen, the authors argued.

Similarly, women age 60 to 69 with category 1 density and no additionally mentioned risk factors would be cost-effectively screened only every three to four years. Screening every three to four years was also recommended as cost-effective for women aged 70 to 79 with BI-RADS category 1 or 2 density and no additional risk factors. All others between 60 and 79 would be cost-effectively screened every two years.
When adjusted for a QALY threshold of $50,000, the authors’ recommendations varied slightly. For example, among the 40 to 49 age group, women with category 3 or 4 density would benefit from biennial screening with either a previous biopsy or family history of breast cancer, as opposed to requiring both, as in the $100,000 analysis.

Schousboe and colleagues noted that, when ignoring costs, “As age or breast density increased, many fewer women needed to be screened to prevent one death from breast cancer.

“Our analyses suggest that recommendations about the frequency of mammography should be personalized on the basis of a woman’s age, breast density, history of breast biopsy and family history of breast cancer, as well as the effect of mammography on her quality of life. This differs from mammography guidelines that recommend mammography every one or two years starting at age 40 or 50 years regardless of other risk factors,” the authors argued.

“Our results indicate that annual mammography is not cost-effective, which matches the conclusion of the USPSTF [U.S. Preventive Services Task Force].”

Schousboe et al acknowledged that their reliance on film mammography data could influence their results, given that digital mammography is believed to be more cost-effective for certain age groups.

The authors of an accompanying editorial, while applauding Schousboe and co-authors’ research, contended that the complexity of risk factors, beyond the criteria considered in the current study, significantly complicated the authors’ recommendations.

“Although risk-based approaches show promise, further research is needed to overcome gaps in our knowledge of the underlying relationships between risk factors and the biology of breast cancer and to surmount the practical communication issues involved in implementing appropriate healthcare utilization based on personalized risk,” wrote Jeanne S. Mandelblatt, MD, MPH, from Lombardi Comprehensive Cancer Center in Washington, D.C.

Nonetheless maintaining the importance of incorporating risk factors, Schousboe and colleagues added that additional factors—beyond the cost-effectiveness of screening for payors—should be considered in defining a mammography screening regimen.