- Last Update On : 2013-01-27
Oncotype DX multi-gene expression test, manufactured by Genomic Health, analyzes the activity of 21 genes within a breast cancer patient’s tumor to help determine the likelihood of recurrence and whether patients will benefit from adjuvant chemotherapy. This test is included in ASCO and NCCN breast cancer treatment guidelines for patients with node-negative breast cancer that is estrogen receptor (ER) positive and/or progesterone receptor (PR) positive.
Oncotype DX assigns a Recurrence Score from 0 to 100 based on the gene expression profile. Higher scores predict a great risk of recurrence and a greater likelihood of benefit from chemotherapy. Lower scores are associated with low risk and minimal chemotherapy benefit. Approximately one third of women with node negative and ER and/or PR positive tumors have been reassigned to a lower risk category and have been spared the expense and adverse effects of chemotherapy.
Breast cancer usually does not recur to three to six years in low risk patients. Long term outcome studies require large numbers of patients. Additional studies are needed to determine if remission rates will remain low in patients who forgo chemotherapy.
Oncotype DX has been widely used in the United States for four years. Approximately 90% of health insurers in the United States cover the cost of the test, which is $4075. Tumor tissue must be sent to Genomic Health, where the testing is performed. Recurrence Scores are sent to the ordering physician within two weeks from the time tumor tissue is received at Genomic Health.