Genomic Health's Oncotype DX genetic test possibly cost effective for certain patients with breast cancer, analysis suggests; more research needed
Monday, December 19 2011 | Comments
Genomic Health Inc.
's Oncotype DX multiparameter genomic test could be cost effective as a screening tool to identify patients with estrogen receptor-positive (ER+), lymph node-positive, early-stage breast cancer who have a low risk of recurrence and might therefore receive little benefit from adjuvant chemotherapy, according to findings from a recent analysis.
However, the authors of the analysis noted that more research is necessary to confirm this possibility, with a particular need for research evaluating long-term outcomes associated with using Oncotype DX to guide chemotherapy decisions in these patients.
The study researchers explained that the Oncotype DX 21-gene assay has been validated as a prognostic tool in ER+, node-negative breast cancer and that the test might also predict which of these patients will derive benefit from chemotherapy.
In addition, they noted, evidence is emerging to suggest that the assay might provide similar information in patients with ER+, lymph node-positive tumors. They conducted their analysis to evaluate the cost effectiveness of the test in these patients.
Specifically, using a hypothetical cohort with a starting age of 60 years, they calculated the costs and benefits associated with using Oncotype DX to identify patients with a low risk of recurrence (who would be exempt from adjuvant chemotherapy) relative to a strategy in which chemotherapy was administered regardless of a patient's level of risk. The analysis was conducted from the perspective of the United Kingdom's National Health Service
and considered direct costs incurred during the remainder of a patient's lifetime. The base year for costs was 2011. Recurrence rates for Oncotype DX-selected risk groups were calculated based on data from the Southwest Oncology Group 8814 trial.
Results of the base-case scenario yielded an incremental cost-effectiveness ratio of $8,852 per quality-adjusted life-year gained for Oncotype DX-directed chemotherapy (in which patients with recurrence scores of 18 or less did not receive chemotherapy) relative to chemotherapy for all patients in the cohort. In this analysis, use of the test to guide chemotherapy decisions led to a small increase in life expectancy; the dominant factor influencing cost effectiveness was the reduced costs associated with less frequent use of chemotherapy.
Assuming a willingness-to-pay threshold of approximately $46,000 (the dollar equivalent of the upper end of the range considered cost effective by the United Kingdom's National Institute for Health and Clinical Excellence
), the probability that the test would be cost effective was 0.61.
Results of the analysis were sensitive to assumptions about recurrence rates, long-term anthracycline-related cardiac toxicity, quality of life, the cost of the test and the time horizon.
According to the study authors, a value-of-information analysis suggested that--to better evaluate the cost effectiveness of the Oncotype DX assay in this patient population--the highest priority for future research is the study of recurrence rates in test-selected subgroups.
The researchers acknowledged additional limitations to their analysis, including the fact that they did not compare the Oncotype DX assay with alternative testing methods, nor did they factor in the possibility that the price of the test might change with the introduction of alternative tests to the market.
This research was published online Dec. 2 ahead of print by the Journal of the National Cancer Institute