Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapy

Background: The 2018 American Society of Clinical Oncology/College of American Pathologists guidelines classified immunohistochemistry (IHC) 1+ or 2+, FISH-negative breast cancer as HER2-low. To date, only a few studies have investigated the role of HER2-low status in patients with hormone receptor...

Full description

Saved in:
Bibliographic Details
Main Authors: Federico Sottotetti, Barbara Tagliaferri, Gianpiero Rizzo, Raffaella Palumbo, Giulia Chessa, Chiara Raso, Lorenzo Perrone, Alberto Malovini, Valentina Tibollo, Laura Deborah Locati, Paolo Pedrazzoli, Angioletta Lasagna
Format: Article
Language:English
Published: BioExcel Publishing Ltd 2025-05-01
Series:Drugs in Context
Subjects:
Online Access:https://www.drugsincontext.com/patterns-of-treatment-and-outcomes-of-patients-with-metastatic-her2-low-breast-cancer-treated-with-cdk4-6-inhibitors-and-hormone-therapy/
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849313926996557824
author Federico Sottotetti
Barbara Tagliaferri
Gianpiero Rizzo
Raffaella Palumbo
Giulia Chessa
Chiara Raso
Lorenzo Perrone
Alberto Malovini
Valentina Tibollo
Laura Deborah Locati
Paolo Pedrazzoli
Angioletta Lasagna
author_facet Federico Sottotetti
Barbara Tagliaferri
Gianpiero Rizzo
Raffaella Palumbo
Giulia Chessa
Chiara Raso
Lorenzo Perrone
Alberto Malovini
Valentina Tibollo
Laura Deborah Locati
Paolo Pedrazzoli
Angioletta Lasagna
author_sort Federico Sottotetti
collection DOAJ
description Background: The 2018 American Society of Clinical Oncology/College of American Pathologists guidelines classified immunohistochemistry (IHC) 1+ or 2+, FISH-negative breast cancer as HER2-low. To date, only a few studies have investigated the role of HER2-low status in patients with hormone receptor positive/HER2– (HR+/HER2–) metastatic breast cancer (MBC) during CDK4/6 inhibitor (CDK4/6i) therapy. Methods: This is a multicentre, retrospective cohort study analysing data from patients with HR+/HER2-low and HR+/HER2-0 MBC treated with CDK4/6i as first-line or second-line therapy at the Oncology Units of IRCCS San Matteo Hospital and ICS Maugeri IRCCS in Pavia, Italy, from January 2017 to October 2023. The aim was to assess the activity and effectiveness of CDK4/6i in a real-life setting. Results: Of the 241 patients included, 240 (99.6%) were women. The median age at diagnosis was 57 years (IQR 48–65 years). Most patients had pM M0 (70.5%). At presentation, 112 (46.5%) had HER2-low and 129 (53.5%) had HER2-0 status. CDK4/6i were administered as first-line therapy in 89.2% of patients and as second-line therapy in 10.8% of patients, with palbociclib (61.4%) being the most common. The median progression-free survival during CDK4/6i therapy was 36.3 months (95% CI 23.6 months to not reached), while the median overall survival was 60.5 months (95% CI 54.4 months to not reached). Progression-free survival differed significantly between palbociclib and abemaciclib/ribociclib (24.4 versus 53.7 months; p=0.0109) and between first-line and second-line therapy (40.5 versus 21.2 months; p=0.0466). Conclusion: CDK4/6i are effective in both HER2-low and HER2-0 MBC, with HER2-low potentially benefiting more from first-line therapy.
format Article
id doaj-art-7f8d11e5ffa5461dbee63bdcc932132d
institution Kabale University
issn 1740-4398
language English
publishDate 2025-05-01
publisher BioExcel Publishing Ltd
record_format Article
series Drugs in Context
spelling doaj-art-7f8d11e5ffa5461dbee63bdcc932132d2025-08-20T03:52:38ZengBioExcel Publishing LtdDrugs in Context1740-43982025-05-011411410.7573/dic.2024-12-1Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapyFederico SottotettiBarbara TagliaferriGianpiero RizzoRaffaella PalumboGiulia ChessaChiara RasoLorenzo PerroneAlberto MaloviniValentina TibolloLaura Deborah LocatiPaolo PedrazzoliAngioletta LasagnaBackground: The 2018 American Society of Clinical Oncology/College of American Pathologists guidelines classified immunohistochemistry (IHC) 1+ or 2+, FISH-negative breast cancer as HER2-low. To date, only a few studies have investigated the role of HER2-low status in patients with hormone receptor positive/HER2– (HR+/HER2–) metastatic breast cancer (MBC) during CDK4/6 inhibitor (CDK4/6i) therapy. Methods: This is a multicentre, retrospective cohort study analysing data from patients with HR+/HER2-low and HR+/HER2-0 MBC treated with CDK4/6i as first-line or second-line therapy at the Oncology Units of IRCCS San Matteo Hospital and ICS Maugeri IRCCS in Pavia, Italy, from January 2017 to October 2023. The aim was to assess the activity and effectiveness of CDK4/6i in a real-life setting. Results: Of the 241 patients included, 240 (99.6%) were women. The median age at diagnosis was 57 years (IQR 48–65 years). Most patients had pM M0 (70.5%). At presentation, 112 (46.5%) had HER2-low and 129 (53.5%) had HER2-0 status. CDK4/6i were administered as first-line therapy in 89.2% of patients and as second-line therapy in 10.8% of patients, with palbociclib (61.4%) being the most common. The median progression-free survival during CDK4/6i therapy was 36.3 months (95% CI 23.6 months to not reached), while the median overall survival was 60.5 months (95% CI 54.4 months to not reached). Progression-free survival differed significantly between palbociclib and abemaciclib/ribociclib (24.4 versus 53.7 months; p=0.0109) and between first-line and second-line therapy (40.5 versus 21.2 months; p=0.0466). Conclusion: CDK4/6i are effective in both HER2-low and HER2-0 MBC, with HER2-low potentially benefiting more from first-line therapy.https://www.drugsincontext.com/patterns-of-treatment-and-outcomes-of-patients-with-metastatic-her2-low-breast-cancer-treated-with-cdk4-6-inhibitors-and-hormone-therapy/abemaciclibantibody–drug conjugatesher2-lowmetastatic breast cancerpalbociclibribociclibtherapeutic strategies
spellingShingle Federico Sottotetti
Barbara Tagliaferri
Gianpiero Rizzo
Raffaella Palumbo
Giulia Chessa
Chiara Raso
Lorenzo Perrone
Alberto Malovini
Valentina Tibollo
Laura Deborah Locati
Paolo Pedrazzoli
Angioletta Lasagna
Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapy
Drugs in Context
abemaciclib
antibody–drug conjugates
her2-low
metastatic breast cancer
palbociclib
ribociclib
therapeutic strategies
title Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapy
title_full Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapy
title_fullStr Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapy
title_full_unstemmed Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapy
title_short Patterns of treatment and outcomes of patients with metastatic HER2-low breast cancer treated with CDK4/6 inhibitors and hormone therapy
title_sort patterns of treatment and outcomes of patients with metastatic her2 low breast cancer treated with cdk4 6 inhibitors and hormone therapy
topic abemaciclib
antibody–drug conjugates
her2-low
metastatic breast cancer
palbociclib
ribociclib
therapeutic strategies
url https://www.drugsincontext.com/patterns-of-treatment-and-outcomes-of-patients-with-metastatic-her2-low-breast-cancer-treated-with-cdk4-6-inhibitors-and-hormone-therapy/
work_keys_str_mv AT federicosottotetti patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT barbaratagliaferri patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT gianpierorizzo patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT raffaellapalumbo patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT giuliachessa patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT chiararaso patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT lorenzoperrone patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT albertomalovini patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT valentinatibollo patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT lauradeborahlocati patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT paolopedrazzoli patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy
AT angiolettalasagna patternsoftreatmentandoutcomesofpatientswithmetastaticher2lowbreastcancertreatedwithcdk46inhibitorsandhormonetherapy