US-based NanoString Technologies has announced that its Prosigna Breast Cancer Prognostic Gene Signature Assay offers better prognostic information in endocrine treated patients with HR+ node negative disease.

NanoString Technologies said that its TransATAC clinical validation study on its PAM50 gene signature-based breast cancer assay, which was published in the Journal of Clinical Oncology, evaluated three kinds of cancer tests in order to forecast the recurrence risk of the disease in the distant future in postmenopausal women, who have been given endocrine therapy for hormone receptor-positive (HR+) breast cancer, which is in the early stage.

The study evaluated 1,017 samples from the Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial of postmenopausal women, who were suffering with HR+ early-stage breast cancer and had undergone endocrine therapy for atleast five years.

The study’s primary aims were to identify if the PAM50 gene signature provided prognostic information to clinical-pathological variables, and to compare the performance of the PAM50 risk of recurrence (ROR) score, the Oncotype DX recurrence score (RS), and the IHC4 score.

It found that the PAM50 ROR score provided more prognostic information compared to the widely used Oncotype DX RS. Moreover, PAM50 ROR score classified fewer number of cancer patients under the intermediate-risk group and more under the high-risk group, than the Oncotype DX RS score, after using defined risk cutoffs for low, intermediate and high risk of less than 10%, between 10% and 20% and more than than 20% estimated risk of recurrence.

NanoString Technologies president and CEO Brad Gray noted that the publication of the TransATAC study is an important milestone in its ongoing effort to enable genomic testing for breast cancer in local laboratories worldwide.

"We look forward to discussing the results and conclusions of this study with oncologists, pathologists and payers in the European Union and other countries that recognise the CE Mark, as we continue with our commercial launch in those regions," Gray added.