Digital mammo plus breast MRI proves clinically beneficial, but not cost-effective

Digital mammography plus MRI is the most clinically effective strategy for screening women carrying a genetic mutation known to increase the risk for breast cancer. However, unless the cost of breast MRI decreases substantially, the modality doesn't translate as cost-effective, according to a study presented on Tuesday at the RSNA 2009 meeting.

Women carrying the BRCA1/BRCA2 genes are 60% to 70% more likely than other women to develop breast cancer. The American Cancer Society recommends those women get screened using breast MRI, but Dr. Janie Lee, a staff radiologist at Massachusetts General Hospital in Boston, said the test doesn't measure up in terms of cost-effectiveness.

Lee and colleagues compared four annual screening strategies with clinical surveillance without imaging for a cohort of 25-year-old BRCA1 mutation carriers. Using a Markov Monte Carlo model, the researchers measured film mammography, digital mammography, film mammography plus MRI, and digital mammography plus MRI.

Digital mammography alone was more effective than film mammography in terms of quality-adjusted life years, or the value for money for a medical intervention. Digital mammography resulted in 44.54 QALYs versus 44.38 for film-screen. Digital mammography plus MRI resulted in 44.63 QALYs versus 44.57 for film-screen plus MRI.

Digital mammography plus MRI was the most effective examination but also had the highest lifetime costs. The incremental cost of adding MRI to digital mammography was $136,583 per QALY gained.

Sensitivity analysis demonstrated the incremental cost-effectiveness ratio for digital mammography and MRI would come down below $100,000 per QALY only if the cost of breast MRI decreased, Lee said.

Annual MRI and digital mammography screening became more cost-effective when the cost of an MRI decreased from $604 to $402, or when mutation penetrance increased from 65% to 71%, she said.

The research was supported in part by grants from the National Institutes of Health.