Real-World Treatment Patterns and Overall Survival (OS) of Patients With Metastatic Triple-Negative Breast Cancer (mTNBC) in Canada
Author(s)
Jan-Willem Henning, MBChB, FRCPC1, Winson Y. Cheung, MD, MPH, FRCPC2.
1Arthur E. Child Comprehensive Cancer Centre, Calgary, AB, Canada, 2Departments of Oncology and Community Health Sciences, Cumming School of Medicine, and Oncology Outcomes, Calgary, AB, Canada.
1Arthur E. Child Comprehensive Cancer Centre, Calgary, AB, Canada, 2Departments of Oncology and Community Health Sciences, Cumming School of Medicine, and Oncology Outcomes, Calgary, AB, Canada.
Presentation Documents
OBJECTIVES: Patients with mTNBC have a poor prognosis; however, Canadian data on this population are limited. This retrospective cohort study described treatment patterns and OS in patients with mTNBC.
METHODS: Data for females aged ≥18 years diagnosed with de novo or recurrent mTNBC between 2015‒2021 were captured from population-level databases in Alberta, Canada. Patients were followed up until December 31st, 2022.
RESULTS: The study included 344 patients with mTNBC, including 120 (34.9%) with de novo disease. Human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) score was 0 in 122 patients (35.5%), 1+ in 123 (35.8%) and 2+/fluorescence in situ hybridization (FISH) negative in 99 (28.8%) patients. First-line (1L) therapy was initiated in 239 patients (69.5%), of whom 129 (54.0%) received second-line (2L) therapy and 66 (27.6%) received third-line (3L) therapy. The most frequent 1L therapy was capecitabine monotherapy (38.5%), in 2L the most frequent therapies were capecitabine and other chemotherapy monotherapy (24.8% each), and in 3L was other therapies, including immunotherapy (IO) (63.6%). Median (Q1, Q3) time to next treatment was 4.8 (2.6, 8.4) months from initiation of 1L, 4.9 (3.0, 9.1) months from 2L, and 4.6 (2.9, 7.6) months from 3L. Median OS (95% confidence interval) was 15.7 (13.8, 18.5) months from the initiation of 1L, 11.4 (9.5, 14.8) months from 2L, and 8.3 (7.6, 12.2) months from 3L. OS was similar when stratified by IHC score.
CONCLUSIONS: These results suggest a persistent high unmet need among patients with mTNBC. Some patients may benefit from new targeted agents that are now reimbursed in Canada, such as chemotherapy with IO for tumors with programmed death-ligand 1 expression and antibody-drug conjugates in 2L and/or 3L for patients with low HER2 expression. Because of poor survival in mTNBC, targeted therapies in the curative setting are research priorities to improve outcomes.
METHODS: Data for females aged ≥18 years diagnosed with de novo or recurrent mTNBC between 2015‒2021 were captured from population-level databases in Alberta, Canada. Patients were followed up until December 31st, 2022.
RESULTS: The study included 344 patients with mTNBC, including 120 (34.9%) with de novo disease. Human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) score was 0 in 122 patients (35.5%), 1+ in 123 (35.8%) and 2+/fluorescence in situ hybridization (FISH) negative in 99 (28.8%) patients. First-line (1L) therapy was initiated in 239 patients (69.5%), of whom 129 (54.0%) received second-line (2L) therapy and 66 (27.6%) received third-line (3L) therapy. The most frequent 1L therapy was capecitabine monotherapy (38.5%), in 2L the most frequent therapies were capecitabine and other chemotherapy monotherapy (24.8% each), and in 3L was other therapies, including immunotherapy (IO) (63.6%). Median (Q1, Q3) time to next treatment was 4.8 (2.6, 8.4) months from initiation of 1L, 4.9 (3.0, 9.1) months from 2L, and 4.6 (2.9, 7.6) months from 3L. Median OS (95% confidence interval) was 15.7 (13.8, 18.5) months from the initiation of 1L, 11.4 (9.5, 14.8) months from 2L, and 8.3 (7.6, 12.2) months from 3L. OS was similar when stratified by IHC score.
CONCLUSIONS: These results suggest a persistent high unmet need among patients with mTNBC. Some patients may benefit from new targeted agents that are now reimbursed in Canada, such as chemotherapy with IO for tumors with programmed death-ligand 1 expression and antibody-drug conjugates in 2L and/or 3L for patients with low HER2 expression. Because of poor survival in mTNBC, targeted therapies in the curative setting are research priorities to improve outcomes.
Conference/Value in Health Info
2025-05, ISPOR 2025, Montréal, Quebec, CA
Value in Health, Volume 28, Issue S1
Code
CO104
Topic
Clinical Outcomes
Topic Subcategory
Comparative Effectiveness or Efficacy
Disease
No Additional Disease & Conditions/Specialized Treatment Areas, SDC: Oncology