ArticleClinical cancer research : an official journal of the American Association for Cancer Research2021
Evaluating Serum Thymidine Kinase 1 in Patients with Hormone Receptor-Positive Metastatic Breast Cancer Receiving First-line Endocrine Therapy in the SWOG S0226 Trial.
Article in Clinical cancer research : an official journal of the American Association for Cancer Research, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 1 of them a synthesis that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
16 citing papers in PubMed, 1 synthesis or guideline pooled it, 17 citations in OpenAlex.
- Elevated thymidine kinase 1 expression at baseline predicts poor prognosis in breast cancer patients.Frontiers in oncology · 2026Pooled it
- The role of serum thymidine kinase 1 activity in neoadjuvant-treated HER2-positive breast cancer: biomarker analysis from the Swedish phase II randomized PREDIX HER2 trial.Breast cancer research and treatment · 2024Trial
- Thymidine kinase activity levels in serum can identify HR+ metastatic breast cancer patients with a low risk of early progression (SWOG S0226).Biomarkers : biochemical indicators of exposure, response, and susceptibility to chemicals · 2023Trial
- Avutometinib, Abemaciclib, and Fulvestrant in Patients with HR+/HER2- Metastatic Breast Cancer Previously Treated with CDK4/6 Inhibitor: A Single-Arm Phase I Trial.Clinical cancer research : an official journal of the American Association for Cancer Research · 2026Article
- Prognostic role of thymidine kinase 1 activity in hormone receptor positive metastatic breast cancer. A systematic review and meta-analysis.Breast (Edinburgh, Scotland) · 2026Review
- WITHDRAWN: From CDK4/6 to CDK2 and KAT: Evolving therapeutic approaches in HR+/HER2- breast cancer.Breast (Edinburgh, Scotland) · 2026Article
- New perspectives on endocrine therapy suitability for hormone receptor-positive metastatic breast cancer in clinical practice.Breast (Edinburgh, Scotland) · 2026Review
- Prognostic performance of thymidine kinase 1 activity in patients with hormone receptor-positive and HER2-negative metastatic breast cancer treated with CDK4/6 and aromatase inhibitors.Breast cancer research and treatment · 2026Observational
- Real-World Plasma Thymidine Kinase Activity in High-Risk and Metastatic Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer Treated With Cyclin-Dependent Kinase 4/6 Inhibitors.JCO precision oncology · 2026Observational
- Thymidine kinase 1 concentration and activity in metastatic breast cancer under CDK4/6 inhibitor therapy.Scientific reports · 2025Article
- Expression Profile of Thymidine Kinase Genes in Cervical Squamous Cell Carcinoma Confirmed by Various Detection Methods.World journal of oncology · 2025Article
- Elevated Levels of Serum Thymidine Kinase 1 Predict Poor Survival for Patients with Metastatic Prostate Cancer.European urology open science · 2024Article
- Article
- Chemokine Analysis in Patients with Metastatic Uveal Melanoma Suggests a Role for CCL21 Signaling in Combined Epigenetic Therapy and Checkpoint Immunotherapy.Cancer research communications · 2023Article
- A phase II trial of an alternative schedule of palbociclib and embedded serum TK1 analysis.NPJ breast cancer · 2022Article
- Prognostic Parameters of Palbociclib in HR+/HER2- Advanced Breast Cancer: A Narrative Review.Technology in cancer research & treatmentReview
Corrections and comments
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Authors and funding
14 authors at 10 institutions in 2 countries.
Funding
Abstract
purposeSerum thymidine kinase 1 (sTK1) activity is associated with poor prognosis in metastatic breast cancer (MBC). We assessed the prognostic effect of sTK1 in patients with hormone receptor-positive MBC treated on a prospective randomized trial of anastrozole (A) versus A plus fulvestrant (A + F). PATIENTS AND
methodssTK1 was assessed in 1,726 serums [baseline (BL), cycles 2, 3, 4, and 7] using the DiviTum assay. A prespecified cutoff of ≥200 Du/L was considered high. Progression-free survival (PFS) and overall survival (OS) were analyzed by Kaplan-Meier, log-rank tests, and Cox regression.
resultsBL sTK1 was elevated in 171 (40%) of 432 patients. Patients with high versus low BL sTK1 had significantly worse PFS [median 11.2 vs. 17.3 months, HR = 1.76; 95% confidence interval (CI; 1.43-2.16);
conclusionsHigh sTK1 at BL and subsequent timepoints is associated with worse prognosis in patients with MBC starting first-line endocrine therapy (ET). Patients with low sTK1 at BL have comparable outcomes on single-agent or combination ET.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.