TY - JOUR
T1 - Gene-expression assays
T2 - New tools to individualize treatment of early-stage breast cancer
AU - Dobbe, Elizabeth
AU - Gurney, Kristen
AU - Kiekow, Sara
AU - Lafferty, Jeffery S.
AU - Kolesar, Jill M.
PY - 2008/1/1
Y1 - 2008/1/1
N2 - Purpose. The clinical and economic data for the two currently available gene-expression assays are reviewed. Summary. Two gene-expression assays, used to determine the risk of breast cancer recurrence in patients with stage I or II node-negative breast cancer, are currently available. Oncotype DX is an assay performed on RNA extracted from paraffin-embedded tumor tissue. It analyzes the expression of 21 genes: 16 cancer-related genes and 5 reference genes. The results are used to calculate a recurrence score to identify the likelihood of cancer recurrence in patients treated with tamoxifen. The results of two studies evaluating the ability of Oncotype DX to predict the risk of breast cancer recurrence suggest that patients with ER-positive, node-negative breast cancer and a low recurrence score may need only adjuvant treatment with tamoxifen, while intermediate- and high-risk patients may require additional treatment with adjuvant chemotherapy. MammaPrint, an oligonucleotide microassay performed on fresh-frozen tumor samples, analyzes the expression of 70 genes. Studies have found that MammaPrint allows young patients (<61 years) with early-stage breast cancer to be categorized as having a high or low risk of distant metastasis. High-risk patients may then be managed with more aggressive therapy. Conclusion. Two gene-expression assays, Oncotype DX and MammaPrint, have been developed to determine the risk of breast cancer recurrence in patients with stage I or II node-negative breast cancer. In the future, these tests may be useful in determining the need for systemic adjuvant therapy in such patients.
AB - Purpose. The clinical and economic data for the two currently available gene-expression assays are reviewed. Summary. Two gene-expression assays, used to determine the risk of breast cancer recurrence in patients with stage I or II node-negative breast cancer, are currently available. Oncotype DX is an assay performed on RNA extracted from paraffin-embedded tumor tissue. It analyzes the expression of 21 genes: 16 cancer-related genes and 5 reference genes. The results are used to calculate a recurrence score to identify the likelihood of cancer recurrence in patients treated with tamoxifen. The results of two studies evaluating the ability of Oncotype DX to predict the risk of breast cancer recurrence suggest that patients with ER-positive, node-negative breast cancer and a low recurrence score may need only adjuvant treatment with tamoxifen, while intermediate- and high-risk patients may require additional treatment with adjuvant chemotherapy. MammaPrint, an oligonucleotide microassay performed on fresh-frozen tumor samples, analyzes the expression of 70 genes. Studies have found that MammaPrint allows young patients (<61 years) with early-stage breast cancer to be categorized as having a high or low risk of distant metastasis. High-risk patients may then be managed with more aggressive therapy. Conclusion. Two gene-expression assays, Oncotype DX and MammaPrint, have been developed to determine the risk of breast cancer recurrence in patients with stage I or II node-negative breast cancer. In the future, these tests may be useful in determining the need for systemic adjuvant therapy in such patients.
KW - Antineoplastic agents
KW - Breast neoplasms
KW - Diagnosis
KW - Genetics
KW - Tamoxifen
KW - Tests
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U2 - 10.2146/ajhp060352
DO - 10.2146/ajhp060352
M3 - Review article
C2 - 18159035
AN - SCOPUS:37849015496
SN - 1079-2082
VL - 65
SP - 23
EP - 28
JO - American Journal of Health-System Pharmacy
JF - American Journal of Health-System Pharmacy
IS - 1
ER -