Common breast cancer test may not be worth the cost, study suggests

A new study by a UCLA researcher in collaboration with colleagues at Harvard and University of Texas Southwestern has found that a genomic test widely used to help determine whether women with a common form of breast cancer should undergo radiation is not cost effective. The Oncotype Dx DCIS test is given to patients with ductal carcinoma in situ (DCIS) to improve treatment selection by better identifying the biological potential of tumors to recur. Medicare reimburses about $3,400 dollars for the Oncotype Dx DCIS test.

Using a standard willingness-to-pay threshold of $100,000 per-quality-adjusted-life-year, implementing the Oncotype Dx DCIS was not cost-effective. However, the researchers noted that implementing the Oncotype Dx DCIS score would reduce the proportion of the population undergoing adjuvant radiation, thus decreasing the number of women at risk for potential side effects. Whether this benefit is sufficient to justify the increased cost should be debated.

Ductal carcinoma in situ (DCIS) comprises approximately 25 percent of breast cancers, and over 60,000 women are diagnosed with it in the United States each year. One of the treatment goals for patients with DCIS is to minimize the risk of a local recurrence while maximizing breast conservation. Despite the significant number of patients with the disease, the risks and optimal treatment remain unknown, resulting in difficulties with clinical decision-making.

Previous research has demonstrated the ability of the Oncotype Dx DCIS test to predict the 10-year risk of developing an ipsilateral breast event (a local recurrence of the DCIS or an invasive carcinoma) in patients with DCIS treated with breast conserving surgery without radiation therapy. These results suggest that the Oncotype Dx DCIS test may have potential for selecting women who may be treated with surgery alone with omission of radiation treatment.

The findings are relevant to physicians to inform them on the cost/benefit of incorporating the DCIS Score into their clinical practice.

The study is published online in the Journal of Clinical Oncology, September 12, 2016.