Mamta Parikh1, Maria Galkin2, Ann Brunson3, Theresa Keegan3, Helen K Chew4. 1. Department of Internal Medicine, Division of Hematology Oncology, UC Davis School of Medicine, United States. 2. Department of Internal Medicine, UC Davis School of Medicine, United States. 3. Center for Oncology and Hematology Outcomes Research and Training (COHORT), Division of Hematology Oncology, UC Davis School of Medicine, United States. 4. Department of Internal Medicine, Division of Hematology Oncology, UC Davis School of Medicine, United States. Electronic address: hkchew@ucdavis.edu.
Abstract
PURPOSE: There is limited data on prognosis of node-negative (N0), HER2-positive (HER2+) small breast cancers. We evaluated breast cancer-specific survival (BCSS) among women diagnosed with T1a/T1b, N0 tumors in California between 2000-2004 and 2005-2012, eras before and after approval of adjuvant trastuzumab. PATIENTS AND METHODS: 45,346 women diagnosed with T1a/b, N0 tumors between January 1, 2000 and December 31, 2012 were identified in the California Cancer Registry (CCR); approximately 10% were HER2 + , and 80% hormone receptor positive (ER and/or PR+). Primary outcome was BCSS, analyzed in 2000-2004 and 2005-2012. Multivariable Cox proportional hazards regression was used to calculate hazard ratios and 95% confidence intervals for mortality, and separately conducted for hormone receptor positive and negative tumors. Kaplan-Meier curves compared BCSS by HER2 status. RESULTS: While BCSS in this cohort exceeded 90%, a significantly higher hazard of breast cancer death was observed in women with HER2+ tumors in the 2000-2004 era. There was no difference in outcomes between T1a and T1b tumors. Women with ER/PR+ tumors had lower hazards of death in both eras, but HER2+ tumors were associated with a higher hazard of death in the 2000-2004 era. Among women with hormone receptor negative tumors, HER2 positive disease was associated with a lower hazard of death in the 2005-2012 era. CONCLUSION: Within this large cohort of T1a/b N0 breast cancers from the CCR, HER2+ tumors were associated with a significantly worse BCSS in the era before adjuvant trastuzumab. A balanced discussion regarding HER2-directed therapies is needed between patient and clinician.
PURPOSE: There is limited data on prognosis of node-negative (N0), HER2-positive (HER2+) small breast cancers. We evaluated breast cancer-specific survival (BCSS) among women diagnosed with T1a/T1b, N0 tumors in California between 2000-2004 and 2005-2012, eras before and after approval of adjuvant trastuzumab. PATIENTS AND METHODS: 45,346 women diagnosed with T1a/b, N0 tumors between January 1, 2000 and December 31, 2012 were identified in the California Cancer Registry (CCR); approximately 10% were HER2 + , and 80% hormone receptor positive (ER and/or PR+). Primary outcome was BCSS, analyzed in 2000-2004 and 2005-2012. Multivariable Cox proportional hazards regression was used to calculate hazard ratios and 95% confidence intervals for mortality, and separately conducted for hormone receptor positive and negative tumors. Kaplan-Meier curves compared BCSS by HER2 status. RESULTS: While BCSS in this cohort exceeded 90%, a significantly higher hazard of breast cancer death was observed in women with HER2+ tumors in the 2000-2004 era. There was no difference in outcomes between T1a and T1b tumors. Women with ER/PR+ tumors had lower hazards of death in both eras, but HER2+ tumors were associated with a higher hazard of death in the 2000-2004 era. Among women with hormone receptor negative tumors, HER2 positive disease was associated with a lower hazard of death in the 2005-2012 era. CONCLUSION: Within this large cohort of T1a/b N0 breast cancers from the CCR, HER2+ tumors were associated with a significantly worse BCSS in the era before adjuvant trastuzumab. A balanced discussion regarding HER2-directed therapies is needed between patient and clinician.
Authors: Yael Artzy-Randrup; Tamir Epstein; Joel S Brown; Ricardo L B Costa; Brian J Czerniecki; Robert A Gatenby Journal: NPJ Breast Cancer Date: 2021-03-11