H F Kennecke1, I A Olivotto2, C Speers3, B Norris4, S K Chia5, C Bryce5, K A Gelmon5. 1. Division of Medical Oncology, British Columbia (BC) Cancer Agency; Department of Medicine, University of British Columbia, Vancouver, BC; Breast Cancer Outcomes Unit. Electronic address: hkenneck@bccancer.bc.ca. 2. Department of Medicine, University of British Columbia, Vancouver, BC; Breast Cancer Outcomes Unit; Population and Preventive Oncology Programs; Victoria. 3. Breast Cancer Outcomes Unit; Population and Preventive Oncology Programs. 4. Department of Medicine, University of British Columbia, Vancouver, BC; Breast Cancer Outcomes Unit; Fraser Valley, BC Cancer Agency, Canada. 5. Division of Medical Oncology, British Columbia (BC) Cancer Agency; Department of Medicine, University of British Columbia, Vancouver, BC; Breast Cancer Outcomes Unit.
Abstract
BACKGROUND: Letrozole after 5 years of adjuvant tamoxifen results in a significant reduction in risk of recurrence from estrogen receptor (ER) positive breast cancer. An individualized estimate of the risk of relapse and death after 5 years of tamoxifen could improve decisions regarding extended hormonal therapy. METHODS: The British Columbia Breast Cancer Outcomes database was used to identify women aged 45 years or older at the time of diagnosis with early-stage (I-IIIA) breast cancer who received tamoxifen and were disease free 5 years after diagnosis. Ten-year breast cancer event rates and mortality were calculated as well as annualized hazard rates of recurrence. RESULTS: A total of 1086 women were identified with a median age of 64 years and follow-up of 10.5 years. The relative risk (RR) of death was 3.1 (P=0.003) and for recurrence was 1.7 (P=0.037) for N1 (one to three positive nodes) versus N0 (zero nodes positive) disease. N2 (four to nine nodes positive) had a RR of 5.8 (P<0.001) for death and 3.0 (P=0.002) for recurrence. Low tumor grade and high ER level subgroups had a more favorable prognosis. Annual breast cancer risk between years 6 and 10 was, respectively, 2.2%, 3.5% and 7.6% for N0, N1 and N2 disease and 2.6% and 4.5% for T1 and T2 breast cancer. CONCLUSION: T and N stages predicted late relapse and death from breast cancer in a population-based cohort of postmenopausal women. Risk estimates reported herein may be used to optimize decision making regarding adjuvant therapy after 5 years of tamoxifen.
BACKGROUND:Letrozole after 5 years of adjuvant tamoxifen results in a significant reduction in risk of recurrence from estrogen receptor (ER) positive breast cancer. An individualized estimate of the risk of relapse and death after 5 years of tamoxifen could improve decisions regarding extended hormonal therapy. METHODS: The British Columbia Breast Cancer Outcomes database was used to identify women aged 45 years or older at the time of diagnosis with early-stage (I-IIIA) breast cancer who received tamoxifen and were disease free 5 years after diagnosis. Ten-year breast cancer event rates and mortality were calculated as well as annualized hazard rates of recurrence. RESULTS: A total of 1086 women were identified with a median age of 64 years and follow-up of 10.5 years. The relative risk (RR) of death was 3.1 (P=0.003) and for recurrence was 1.7 (P=0.037) for N1 (one to three positive nodes) versus N0 (zero nodes positive) disease. N2 (four to nine nodes positive) had a RR of 5.8 (P<0.001) for death and 3.0 (P=0.002) for recurrence. Low tumor grade and high ER level subgroups had a more favorable prognosis. Annual breast cancer risk between years 6 and 10 was, respectively, 2.2%, 3.5% and 7.6% for N0, N1 and N2 disease and 2.6% and 4.5% for T1 and T2 breast cancer. CONCLUSION: T and N stages predicted late relapse and death from breast cancer in a population-based cohort of postmenopausal women. Risk estimates reported herein may be used to optimize decision making regarding adjuvant therapy after 5 years of tamoxifen.
Authors: B B Oven Ustaalioglu; O Balvan; A Bilici; A Develi; M Aliustaoglu; F A Vardar; B Erkol Journal: Clin Transl Oncol Date: 2015-06-17 Impact factor: 3.405
Authors: Sarah Nechuta; Wendy Y Chen; Hui Cai; Elizabeth M Poole; Marilyn L Kwan; Shirley W Flatt; Ruth E Patterson; John P Pierce; Bette J Caan; Xiao Ou Shu Journal: Int J Cancer Date: 2015-12-09 Impact factor: 7.396