NEW YORK (GenomeWeb) – In an update to its 2018 breast cancer guidelines, the National Comprehensive Cancer Network (NCCN) has made changes in how it endorses the use of, or how it describes, various genetic tests. One major change involved the categorization of Genomic Health's Oncotype DX Breast Recurrence Score as a "preferred" test for chemotherapy treatment decision-making in patients with node-negative early-stage breast cancer.
In node-negative, hormone receptor-positive, HER-2-negative disease, the guidelines' treatment algorithm now recommends doctors "strongly consider" using Oncotype DX, rather than simply "consider" the test. In a reflection of the publication of long-term follow-up data from the TAILORx trial this summer, the NCCN now also recommends that physicians consider the use of adjuvant chemotherapy in women 50 and under who have Oncotype recurrence scores between 16 and 25.
Version 2 of the 2018 guidelines also includes a new page listing and a categorization of various multigene assays that are currently on the market and that can be used to guide decision-making on the use of adjuvant chemotherapy. Oncotype DX is the only "preferred" test on the list and the only assay that is predictive of chemotherapy benefit in node-negative patients, Genomic Health said.
Agendia's Mammaprint is listed as having Level 1 evidence for prognostic use in patients with up to three positive lymph nodes. Nanostring's Prosigna and Myriad Genetics' Endopredict are listed as having Level 2A evidence for the same population, and Biotheranostics' Breast Cancer Index is noted as having Level 2A evidence for only node-negative tumors.
Reflecting this, the guidelines update also includes a new page outlining an algorithm for treatment of women with node-positive disease, which recommends the use of a multigene assay to guide decisions on whether or not to use adjuvant chemotherapy in patients with up to three positive nodes.
Footnotes to the algorithm state that no assays have so-far proven themselves predictive of therapy benefit in this population, but that their prognostic readout can help doctors decide whether a patient should get adjuvant chemo. The NCCN advised that there is some evidence that Genomic Health's test may be predictive, but definitive results are still outstanding.