Hadar Goldvaser1, Tristan A Barnes1, Boštjan Šeruga1, David W Cescon1, Alberto Ocaña1, Domen Ribnikar1, Eitan Amir1. 1. Division of Medical Oncology, University of Toronto and Princess Margaret Cancer Centre, Toronto, Canada; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Medical Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia; Research Unit, Albacete University Hospital, Albacete, Spain; Translational Oncology Laboratory, Regional Center for Biomedical Research, Castilla La Mancha University, Albacete, Spain.
Abstract
Background: A number of randomized controlled trials (RCTs) have reported improvement in breast cancer outcomes from extending treatment with aromatase inhibitors (AIs) beyond the initial five years after diagnosis. However, the toxicity profile of extended AIs is uncertain. Methods: We identified RCTs that compared extended AIs to placebo or no treatment using MEDLINE and a review of abstracts from key conferences between 2013 and 2016. Odds ratios (ORs), 95% confidence intervals (CIs), absolute risks, and the number needed to harm (NNH) were computed for prespecified safety and tolerability outcomes including cardiovascular events, bone fractures, second cancers (excluding new breast cancer), treatment discontinuation for adverse events, and death without recurrence. All statistical tests were two-sided. Results: Seven trials comprising 16 349 patients met the inclusion criteria. Longer treatment with AIs was associated with increased odds of cardiovascular events (OR = 1.18, 95% CI = 1.00 to 1.40, P = .05, NNH = 122), bone fractures (OR = 1.34, 95% CI = 1.16 to 1.55, P < .001, NNH = 72), and treatment discontinuation for adverse events (OR = 1.45, 95% CI = 1.25 to 1.68, P < .001, NNH = 21). Longer treatment with AIs did not influence the odds of either second malignancy (OR = 0.93, 95% CI = 0.73 to 1.18, P = .56) or deaths without breast cancer recurrence (OR = 1.11, 95% CI = 0.90 to 1.36, P = .34). Conclusions: Extended treatment with AIs is associated with an increased risk of cardiovascular events and bone fractures. There is no statistically significant increase in deaths without breast cancer recurrence among patients receiving longer treatment with AIs. These data should be taken into account when considering extended adjuvant AIs.
Background: A number of randomized controlled trials (RCTs) have reported improvement in breast cancer outcomes from extending treatment with aromatase inhibitors (AIs) beyond the initial five years after diagnosis. However, the toxicity profile of extended AIs is uncertain. Methods: We identified RCTs that compared extended AIs to placebo or no treatment using MEDLINE and a review of abstracts from key conferences between 2013 and 2016. Odds ratios (ORs), 95% confidence intervals (CIs), absolute risks, and the number needed to harm (NNH) were computed for prespecified safety and tolerability outcomes including cardiovascular events, bone fractures, second cancers (excluding new breast cancer), treatment discontinuation for adverse events, and death without recurrence. All statistical tests were two-sided. Results: Seven trials comprising 16 349 patients met the inclusion criteria. Longer treatment with AIs was associated with increased odds of cardiovascular events (OR = 1.18, 95% CI = 1.00 to 1.40, P = .05, NNH = 122), bone fractures (OR = 1.34, 95% CI = 1.16 to 1.55, P < .001, NNH = 72), and treatment discontinuation for adverse events (OR = 1.45, 95% CI = 1.25 to 1.68, P < .001, NNH = 21). Longer treatment with AIs did not influence the odds of either second malignancy (OR = 0.93, 95% CI = 0.73 to 1.18, P = .56) or deaths without breast cancer recurrence (OR = 1.11, 95% CI = 0.90 to 1.36, P = .34). Conclusions: Extended treatment with AIs is associated with an increased risk of cardiovascular events and bone fractures. There is no statistically significant increase in deaths without breast cancer recurrence among patients receiving longer treatment with AIs. These data should be taken into account when considering extended adjuvant AIs.
Authors: Giuseppe Curigliano; Evandro de Azambuja; Daniel Lenihan; Maria Grazia Calabrò; Daniela Cardinale; Carlo Maria Cipolla Journal: Oncologist Date: 2019-05-07
Authors: Lindsay J Collin; Alyssa N Troeschel; Yuan Liu; Keerthi Gogineni; Kylee Borger; Kevin C Ward; Lauren E McCullough Journal: Ann Cancer Epidemiol Date: 2020-03-31