First-line treatment with a cyclin-dependent kinase 4/6 inhibitor combined with an aromatase inhibitor for hormone receptor-positive, human epidermal growth factor receptor-2 negative metastatic breast cancer: Population-based outcomes for patients treated in Alberta, Canada.
Bibliographic record
Abstract
e13020 Background: Cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) in combination with an aromatase inhibitor (AI) has emerged as the standard first line treatment in patients with hormone receptor positive, human epidermal growth factor receptor-2 (HER-2) negative metastatic breast cancer (MBC). In this analysis, we describe population-based outcomes for first-line treatment with a CDK4/6i combined with an AI. Methods: All patients who were prescribed CDK4/6i + AI from January 2016 through June 2019 in a large Canadian province were included. Descriptive statistics were used to summarize patient demographics, tumor and treatment characteristics. Survival distributions were estimated using the Kaplan-Meier method. Multivariate analysis (MVA) using a Cox proportional hazards model was constructed to examine associations between potentially prognostic clinical variables and progression free survival (PFS). Results: A total of 316 patients were included. Median age was 61 years (interquartile range, 53-70 years), 82% were postmenopausal women, 39% had de novo MBC, and 48% had non-visceral disease. Palbociclib was prescribed in 94% of patients and the remaining patients received ribociclib. The CDK4/6i was dose-reduced upfront or during treatment in 47%. While 70% of the patients discontinued treatment due to progression, 30% stopped due to toxicity/patient preference/physician recommendation. With a median follow-up of 28.1 months, the median PFS was 37.9 months (95% CI, 26.7-NR). In the MVA, PR-negative tumour (HR, 2.37; 95% CI, 1.45-3.88; P = 0.001) and dose reduction of the CDK4/6i (HR, 1.51; 95% CI, 1.06-2.16; P = 0.022) predicted worse PFS. Median overall survival (OS) was not reached. The 30-month and 36-month OS rates were 74% and 68%, respectively. Of patients who progressed (n = 131), 89% received second-line treatment (chemotherapy in 46%, single agent hormonal therapy in 35%, hormonal therapy plus a targeted agent in 15%, and other in 4%). Median time to progression on second line chemotherapy was 9.0 (5.8-17.6) months and second line hormonal therapy +/- targeted agent was 4.0 (3.4-8.6) months (P = 0.012). Conclusions: The real-world outcomes of first-line use of CDK4/6i and AI are encouraging. PR negative tumors and dose reduction appear to be negative prognostic markers. CDK4/6i + AI as first-line treatment for HR-positive, HER2-negative MBC in Alberta is justified based on favorable PFS and early OS outcomes.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.003 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".