SAN ANTONIO – Universal testing with the 21-gene Oncotype DX assay at diagnosis of estrogen receptor–positive breast cancer could save $330.8 million annually in the United States through avoidance of ineffective chemotherapy, according to a retrospective study involving analysis of nearly 200,000 estrogen receptor-positive tumor samples.
"We believe a low risk score on the assay is presently the most reliable biomarker for a chemotherapy-resistant phenotype. And we believe that the excess harm of chemotherapy outweighs the potential benefit of chemotherapy for those patients," Dr. Joseph Ragaz declared at the San Antonio Breast Cancer Symposium.
His analysis of tumor samples from 196,967 estrogen receptor–positive breast cancer patients in assay parent company Genomic Health’s database showed that a low 10-year recurrence risk score on the Oncotype DX assay – that is, a score of less than 18 – was more common among patients with axillary node–positive women than node-negative women. A low risk score was present in 59% of the nearly 14,000 patients with node-positive disease, compared with 54% of those with node-negative disease.
Prior major retrospective studies have shown no significant benefit of adjuvant chemotherapy in estrogen receptor–positive breast cancer patients with a low risk score on the assay, regardless of whether they had node-positive (Lancet Oncology 2010;11:55-65) or node-negative disease (J. Clin. Oncol. 2006;24:3726-34).
With an estimated 225,000 new cases of breast cancer per year in the United States, there are 94,500 patients who are estrogen receptor–positive and could be considered candidates for chemotherapy according to current widespread practice. At an estimated cost of chemotherapy of $15,000 per patient and $4,000 per Oncotype DX assay, avoidance of chemotherapy in all such patients who have a low risk score on the assay would save $330.8 million annually in the United States, according to Dr. Ragaz of the University of British Columbia, Vancouver.
In light of these data, he argued that both ethics and economics dictate universal Oncotype DX testing should be done in all estrogen receptor–positive breast cancer patients who are candidates for chemotherapy, regardless of their axillary node status. Moreover, practice guidelines should be revised to avoid chemotherapy in all patients with a low risk score, regardless of nodal status.
"Until prospective randomized trials confirm chemotherapy benefit among low risk score patients, its use among these chemotherapy-resistant cases should be considered investigational," Dr. Ragaz asserted.
|
Dr. Thomas J. Smith
|
"Pretty strong stuff," said session chair Dr. Thomas J. Smith, director of palliative care and Harry J. Duffey Family Professor of Palliative Care at Johns Hopkins University, Baltimore.
"You’re suggesting that we should really change our whole way of practice, and everyone who’s estrogen receptor–positive should have the Oncotype DX, and that should be the basis on which we give chemotherapy," he said as Dr. Ragaz nodded in agreement.
It’s a proposal with considerable appeal, Dr. Smith said. Not only would it save one-third of a billion dollars annually in avoided ineffective chemotherapy – at a time when oncology is increasingly drawing criticism for wasteful spending – but women with a low risk score would also be spared the associated chemotherapy toxicities. Not to mention the patient inconvenience and travel time entailed in a year’s worth of adjuvant chemotherapy. Indeed, this strategy would generate considerable additional savings in terms of the large carbon footprint it would erase, he added.
Submitting your vote...
