What is the Oncotype DX 21-gene assay?
- The Oncotype DX 21-gene assay analyzes the expression of 16 cancer-related genes and 5 reference genes in tumor samples to provide a Recurrence Score result[8].
- NCCN Guidelines recommend Oncotype DX testing for patients with early-stage, hormone receptor-positive (HR+), HER2-negative breast cancer[5][6]:
– It is the preferred test for both node-negative and postmenopausal node-positive (1-3 nodes) patients
– It is strongly considered for node-negative patients
– It can be considered for premenopausal node-positive patients
- The test helps predict:
– Risk of distant recurrence with endocrine therapy alone
– Likelihood of chemotherapy benefit
– Overall prognosis
- Key clinical trials supporting its use:
– TAILORx: Showed 85% of node-negative patients may avoid chemotherapy[8]
– RxPONDER: Demonstrated most women with 1-3 positive nodes and Recurrence Score 0-25 can forgo chemotherapy[8]
- Recurrence Score results guide treatment decisions:
– Low scores (0-25): Endocrine therapy alone is generally recommended
– High scores (26-100): Chemotherapy is recommended in addition to endocrine therapy
- The test has been shown to change treatment recommendations in 26.8% of cases, often sparing patients from unnecessary chemotherapy[3].
- Oncotype DX is the only test recognized by NCCN guidelines to predict adjuvant chemotherapy benefit specifically[5][6].
- It is considered cost-effective by providing more precise treatment recommendations[5].
In summary, the Oncotype DX 21-gene assay is a valuable tool recommended by NCCN guidelines to help determine whether adjuvant chemotherapy is needed in HR+, HER2-negative early breast cancer. It does not specify which type of chemotherapy to use, but rather helps decide if chemotherapy would be beneficial in addition to endocrine therapy.
Citations:
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4204201/
[2] https://breast-cancer-research.biomedcentral.com/articles/10.1186/s13058-021-01453-4
[3] https://www.nature.com/articles/bjc2013207
[4] https://www.oncotypeiq.com/en-ca/breast-cancer/healthcare-professionals/oncotype-dx-breast-recurrence-score/inclusion-in-guidelines
[5] https://www.oncotypeiq.com/en-gb/breast-cancer/healthcare-professionals/oncotype-dx-breast-recurrence-score/oncotype-dx-in-guidelines
[6] https://onco-hema.healthbooktimes.org/article/82123-benefits-and-applications-of-oncotype-dx-breast-recurrence-score-testing-among-breast-cancer-patients-current-recommendations-and-controversies
[7] https://education.nccn.org/node/11346
[8] https://precisiononcology.exactsciences.com/healthcare-providers/treatment-determination/breast-cancer/oncotype-dx-breast-recurrence-score