Endocrine Sensitivity Measure Predicts Breast Cancer Survival
Survival benefit of endocrine therapy appears linked with estrogen receptor-related transcription
MONDAY, Aug. 9 (HealthDay News) -- A patient's sensitivity to endocrine therapy (SET) index, a measure of estrogen receptor-related transcriptional activity, appears to be predictive of distant relapse-free survival in breast cancer patients who receive endocrine therapy alone or endocrine therapy after chemotherapy, but not in those who receive no adjuvant therapy, according to research published online Aug. 9 in the Journal of Clinical Oncology.
W. Fraser Symmans, M.D., of the University of Texas M.D. Anderson Cancer Center in Houston, and colleagues evaluated the association of SET index and ESR1 levels with risk of distant relapse using microarrays of breast cancer patients receiving three types of treatment. The purpose of the study was to see how estrogen receptor-related gene expression related to tumoral sensitivity to adjuvant endocrine therapy. One group consisted of two cohorts of patients who received five years of tamoxifen alone, one group received tamoxifen and/or an aromatase inhibitor after neoadjuvant chemotherapy, and the third group consisted of two cohorts that did not receive adjuvant systemic therapy.
The researchers found a significant association between the SET index and distant relapse or risk of death in the patients treated with tamoxifen and in the patients treated with endocrine therapy following neoadjuvant chemotherapy. The SET index was not prognostic in the patients receiving no treatment. There were no distant relapses or deaths in tamoxifen-only patients with high SET and node-negative disease, or in chemo-endocrine patients with intermediate or high SET.
"The SET index of estrogen receptor-related transcription predicted survival benefit from adjuvant endocrine therapy, not inherent prognosis. Prior chemotherapy seemed to enhance the efficacy of adjuvant endocrine therapy related to SET index," the authors write.
Two authors disclosed financial relationships with Nuvera Biosciences.