The HER2-TRENDS StudyHR Positive - HER2 Negative Metastatic Breast Cancer (mBC) Treatment Patterns and Clinical Outcomes in Canada
Author(s)
Maud Marques, PhD1, Karen Gambaro, PhD1, Kahina Rachedi, MD1, Mark Basik, MD2, Fred Saad, MD3, François Vincent, MD4, Helen Mackay, MD5, Mahmoud Abdelsalam, MD6, Steven M. Yip, MD7, Simran Shokar, BSc, MPH8, Zhor Senhaji Mouhri, PhD9, Matthew Badin, MSc, MBA9, Kristoph Klein-Panneton, MSc9, Gerald Batist, MD10;
1Exactis Innovation, Montreal, QC, Canada, 2Jewish General Hospital, Montreal, QC, Canada, 3Centre Hospitalier de l’Université de Montréal, Montreal, QC, Canada, 4Centre Intégré Universitaire de Santé et Services Sociaux, Trois-Rivières, QC, Canada, 5Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, ON, Canada, 6The Moncton City Hospital, Moncton, NB, Canada, 7Arthur Child Comprehensive Cancer Centre, Calgary, AB, Canada, 8Astrazeneca, Mississauga, ON, Canada, 9AstraZeneca Canada Inc, Mississauga, ON, Canada, 10Segal Cancer Center, Jewish General Hospital/McGill, Montreal, QC, Canada
1Exactis Innovation, Montreal, QC, Canada, 2Jewish General Hospital, Montreal, QC, Canada, 3Centre Hospitalier de l’Université de Montréal, Montreal, QC, Canada, 4Centre Intégré Universitaire de Santé et Services Sociaux, Trois-Rivières, QC, Canada, 5Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, ON, Canada, 6The Moncton City Hospital, Moncton, NB, Canada, 7Arthur Child Comprehensive Cancer Centre, Calgary, AB, Canada, 8Astrazeneca, Mississauga, ON, Canada, 9AstraZeneca Canada Inc, Mississauga, ON, Canada, 10Segal Cancer Center, Jewish General Hospital/McGill, Montreal, QC, Canada
OBJECTIVES: This study aimed to describe the clinical trajectories of Canadian patients diagnosed with HR+/HER2- mBC, focusing on their treatment patterns, clinical outcomes, and prevalence and testing patterns for AKT/PIK3CA/PTEN biomarkers.
METHODS: A retrospective, longitudinal cohort study utilized real-world data from the pan-Canadian Personalize My Treatment (PMT) cancer registry. The cohort included 387 patients with de novo or recurrent HR+/HER2- mBC diagnosed between January 1, 2015, and March 31, 2022, with a median follow-up of 54.1 months. Treatment patterns and overall survival (OS) were analyzed, along with molecular testing rates for AKT/PIK3CA/PTEN biomarkers.
RESULTS: Among the 387 patients, 80% resided in Quebec, and 20% presented with de novo metastatic disease. testing for AKT/PIK3CA/PTEN was conducted in 32% of patients, with a 23.2% positivity rate for PIK3CA, 2% for PTEN and 1.4% for AKT alterations. The median OS of 65.90 months (IQR: 60.2-77.2).CDK4/6 inhibitors (CDK4/6i) with endocrine therapy (ET) were the predominant choice for first-line (1L) treatment (55.0%), while targeted therapies accounted for 22.9% in second-line (2L). Chemotherapy, particularly mono-chemotherapy, became predominant in third-line (3L) treatments (42.7%). ET rechallenging, wherein patients receive ET regimens sequentially, occurred in 40.8% of patients. Median treatment durations declined across lines: 21.50 months in 1L, 8.13 months in 2L, and 5.63 months in 3L. Median overall survival was 65.90 months, 38.87 months, and 27.37 months from start of 1L, 2L, and 3L, respectively.
CONCLUSIONS: This study highlights the evolving treatment landscape of HR+/HER2- mBC in Canada. Therapies with an endocrine backbone were the preferred choice in earlier lines while later lines reflected the transition to chemotherapy due to loss of endocrine sensitivity. Limited AKT/PIK3CA/PTEN testing underscores opportunities for improvements in biomarker-driven strategies. Small sample sizes and censoring biases highlight the need for larger datasets in future research.
METHODS: A retrospective, longitudinal cohort study utilized real-world data from the pan-Canadian Personalize My Treatment (PMT) cancer registry. The cohort included 387 patients with de novo or recurrent HR+/HER2- mBC diagnosed between January 1, 2015, and March 31, 2022, with a median follow-up of 54.1 months. Treatment patterns and overall survival (OS) were analyzed, along with molecular testing rates for AKT/PIK3CA/PTEN biomarkers.
RESULTS: Among the 387 patients, 80% resided in Quebec, and 20% presented with de novo metastatic disease. testing for AKT/PIK3CA/PTEN was conducted in 32% of patients, with a 23.2% positivity rate for PIK3CA, 2% for PTEN and 1.4% for AKT alterations. The median OS of 65.90 months (IQR: 60.2-77.2).CDK4/6 inhibitors (CDK4/6i) with endocrine therapy (ET) were the predominant choice for first-line (1L) treatment (55.0%), while targeted therapies accounted for 22.9% in second-line (2L). Chemotherapy, particularly mono-chemotherapy, became predominant in third-line (3L) treatments (42.7%). ET rechallenging, wherein patients receive ET regimens sequentially, occurred in 40.8% of patients. Median treatment durations declined across lines: 21.50 months in 1L, 8.13 months in 2L, and 5.63 months in 3L. Median overall survival was 65.90 months, 38.87 months, and 27.37 months from start of 1L, 2L, and 3L, respectively.
CONCLUSIONS: This study highlights the evolving treatment landscape of HR+/HER2- mBC in Canada. Therapies with an endocrine backbone were the preferred choice in earlier lines while later lines reflected the transition to chemotherapy due to loss of endocrine sensitivity. Limited AKT/PIK3CA/PTEN testing underscores opportunities for improvements in biomarker-driven strategies. Small sample sizes and censoring biases highlight the need for larger datasets in future research.
Conference/Value in Health Info
2025-05, ISPOR 2025, Montréal, Quebec, CA
Value in Health, Volume 28, Issue S1
Code
RWD150
Topic
Real World Data & Information Systems
Disease
No Additional Disease & Conditions/Specialized Treatment Areas, SDC: Oncology