Routine use of Oncotype DX genomic testing in women with ER+/HER2- early stage breast cancer can safely guide decision-making about the use of adjuvant chemotherapy, Australian research suggests.
Yet women don’t have access to reimbursement for these costly tests, either from the public purse or private health funds, according to local clinicians.
A study of 71 patients at the Sydney Adventist Hospital who underwent testing after definitive surgery between 2012 and 2016 designated 14% at low risk (Recurrence Score <11), 63% at intermediate risk (RS 11-25) and 23% at high risk of recurrence (RS>25).
None of the low risk patients received chemotherapy in addition to endocrine therapy, while 2% of the intermediate risk patients received both therapies and almost all (94%) of the high risk patients (94%).
The study, published in The Breast Journal, found the absolute risk of metastasis was 10% in the low-risk group, 7% in the intermediate-risk group, and 6% in the high-risk group.
“Patients in the high-risk RS group would appear to have gained benefit from adjuvant chemotherapy given there was only one recurrence in this group despite their higher risk of disease after at least 5 years of follow-up,” the authors wrote.
“Patients in the low-risk RS groups on the other hand avoided chemotherapy with a systemic recurrence rate of 6%. This recurrence rate is consistent with the expected risk of relapse and confirms that this group was one for which the addition of chemotherapy would unlikely further reduce the rate of recurrence.”
The study findings were consistent with those of the TAILORx study, previously reported in the limbic, which found adjuvant chemotherapy was not beneficial in patients with an intermediate Oncotype DX recurrence-score of 11 to 25.
The authors said the growing evidence that multigene assays such as Oncotype DX can help personalise systemic adjuvant therapy choices, and safely spare lower risk women from the side effects of chemotherapy, raises the ongoing issue of funding for such tests.
“Despite the increasing evidence and several international breast cancer guidelines recommending the use of genomic assay tests, the lack of Medicare and private health fund reimbursement means that they are seldomly utilised in Australia as the cost is prohibitive (approximately $5000 for Oncotype DX) for most patients,” they wrote
“In other countries such as the United States, all major insurers cover the cost of genomic assay tests for eligible patients with early breast cancer. If we are to provide the best medical care, national funding needs to be available,” the investigators said.
In July the Medicare Services Advisory Committee (MSAC) announced its rejection of applications for public funding for three gene expression profiling (GEP) tests in early breast cancer. It said the tests provided some modest prognostic information, but none of the test sponsors had provided sufficient evidence for additional prognostic value beyond current standard of care, and thus the economic and financial basis for funding could not be determined.
In its decision, MSAC stated that: “it did not accept predictive value had been adequately demonstrated for any GEP test, and recalled its recent conclusion of worse cancer outcomes with an applicant’s proposed predictive use of one GEP test.”