CDK 4/6 inhibitors mired in
uncertainty in HR positive and HER2 negative early breast cancer
The Breast:
VOLUME 55, P75-78, FEBRUARY 01,
2021
by Serena Di Cosimo, Luca Porcu, Fatima Cardoso
Highlights
•HR+/HER2-early BC patients have continuous risk of relapse
and need new therapies
•Current short follow-up precludes any final conclusion
re. adjuvant CDK4/6 inhibitors
•The proportional hazard assumption was hampered by the low
number of events
•Wide point estimate 95%CI translated into imprecise number
needed to treat (NNT)
•Besides efficacy, toxicity, compliance and cost are issues
to consider in decision-making
•Research efforts need to continue to establish CDK4/6
inhibitor predictive biomarkers
Abstract
Cell-cycle abnormalities are common in estrogen receptor-
and/or progesterone receptor-positive, and HER2-non-overexpressing (HR+/HER2-)
breast cancer, and have long been considered potential therapeutic targets.
Cyclin-dependent kinase (CDK) 4/6 inhibitors have dramatically changed the
therapeutic management of HR+/HER2-advanced breast cancer by prolonging
progression-free and overall survival when given in combination with endocrine
therapy. In this article, available data from PALLAS and monarchE trials
regarding the efficacy and toxicity of adjuvant combined therapy with CDK 4/6
inhibitors and endocine therapy in HR+/HER2-early breast cancer are reviewed,
and relevant issues including study hypothesis, patient selection, and duration
of follow-up are discussed.
