protocolSection identificationModule nctId: NCT06307457, orgStudyIdInfo id: A5481188, briefTitle: A Study of HR+/HER2- Metastatic Breast Cancer Patients Treated With Palbociclib Together With an Aromatase Inhibitor From 2017 to 2023 in Denmark., statusModule overallStatus: ACTIVE_NOT_RECRUITING, startDateStruct date: 2024-03-06, primaryCompletionDateStruct date: 2024-08-31, completionDateStruct date: 2024-08-31, studyFirstPostDateStruct date: 2024-03-12, lastUpdatePostDateStruct date: 2024-03-27, sponsorCollaboratorsModule leadSponsor name: Pfizer, class: INDUSTRY, descriptionModule briefSummary: The purpose of this study is to describe the effect of the medicine palbociclib when given together with an aromatase inhibitor for treatment of breast cancer. The study will consider participants who:* have advanced or metastatic breast cancer that is spread to other parts of the body.* have HR+/HER2- (hormone receptor positive\* / human epidermal growth factor receptor 2 negative\*\*) breast cancer types.  * Hormone receptor positive (HR+): are cells that have a group of proteins that bind to a specific hormone. For example, some breast cancer cells have receptors for the hormones estrogen or progesterone.These cells are hormone receptor positive, and they need estrogen or progesterone to grow. This can affect how the cancer is treated. Knowing if the cancer is hormone receptor positive may help plan treatment.* Human epidermal growth factor receptor 2 negative (HER2-): cells that have a small amount or none of a protein called HER2 on their surface. In normal cells, HER2 helps control cell growth. Cancer cells that are HER2 negative may grow more slowly and are less likely to recur (come back) or spread to other parts of the body than cancer cells that have a large amount of HER2 on their surface. Checking to see if a cancer is HER2 negative may help plan treatment.  * have started treatment in the period between January 2017 and December 2021.The study will describe the treatment effect for different patient groups in terms of age and comorbidities. Comorbidity is the condition of having two or more diseases at the same time. The data is collected by the Danish Breast Cancer Group in the period between 2017 to 2023., conditionsModule conditions: Breast Cancer, designModule studyType: OBSERVATIONAL, designInfo observationalModel: COHORT, timePerspective: RETROSPECTIVE, enrollmentInfo count: 580, type: ESTIMATED, armsInterventionsModule interventions name: Palbociclib in combination with AI, outcomesModule primaryOutcomes measure: Progression-free Survival (PFS) of all mBC patients receiving palbociclib in combination with AI as first-line treatment, primaryOutcomes measure: Overall Survival (OS) of all mBC patients receiving palbociclib in combination with AI as first-line treatment, secondaryOutcomes measure: Age distribution in the full data set of mBC patients receiving palbociclib + AI as first-line treatment, secondaryOutcomes measure: PFS in mBC patients below 65 years of age receiving palbociclib + AI as first-line treatment, secondaryOutcomes measure: PFS in mBC patients between 65-74 years of age receiving palbociclib + AI as first-line treatment, secondaryOutcomes measure: PFS in mBC patients 75+ years of age receiving palbociclib + AI as first-line treatment, secondaryOutcomes measure: OS in mBC patients below 65 years of age receiving palbociclib + AI as first-line treatment, secondaryOutcomes measure: OS in mBC patients between 65-74 years of age receiving palbociclib + AI as first-line treatment, secondaryOutcomes measure: OS in mBC patients 75+ years of age receiving palbociclib + AI as first-line treatment, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into Charlson Comorbidity Index (CCI) point score of 0, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into CCI point score of 1, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into CCI point score of 2, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into CCI point score of 3 or higher (3+), secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into CCI point score of 0, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into CCI point score of 1, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into CCI point score of 2, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into CCI point score of 3 or higher (3+), secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment no comorbidity, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment one comorbidity, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment with two or more comorbidities, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment no comorbidity, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment one comorbidity, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment with two or more comorbidities, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Cardiac disease, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Vascular disease, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Metabolic disease, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Psychiatric disease, secondaryOutcomes measure: PFS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Blood and lymphatic system, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Cardiac disease, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Vascular disease, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Metabolic disease, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Psychiatric disease, secondaryOutcomes measure: OS in the full dataset of mBC patients receiving palbociclib + AI as first-line treatment split into type of comorbidity: Blood and lymphatic system, eligibilityModule sex: ALL, minimumAge: 18 Years, stdAges: ADULT, stdAges: OLDER_ADULT, contactsLocationsModule locations facility: Copenhagen University Hospital, Rigshospitalet, city: Copenhagen, zip: 2100, country: Denmark, geoPoint lat: 55.67594, lon: 12.56553, hasResults: False