Tests of gene patternsResearchers have found that looking at the patterns of a number of different genes at the same time (sometimes referred to as gene expression profiling) can help predict whether or not an early stage breast cancer is likely to come back after initial treatment. Two such tests, which look at different sets of genes, are now available: the ® and the MammaPrint®
Oncotype DX®: The may be helpful when deciding whether additional (adjuvant) treatment with chemotherapy (after surgery) might be useful in women with certain early-stage breast cancers that usually have a low chance of coming back (stage I or II estrogen receptor–positive breast cancers without ). Recent data has shown it may also be helpful for patients with positive lymph nodes.
The test looks at a set of 21 genes in cells from tumor samples to determine a 'recurrence score', which is a number between 0 and 100:
- Women with a recurrence score of 17 or below have a low risk of recurrence (coming back after treatment).
- Those with a score of 18 to 30 are at intermediate risk.
- Women with a score of 31 or more are at high risk.