Evidence map›Paper›PMID 38901825›Full record

ArticleCancer research and treatment2025

Endoxifen Concentration Is Associated with Recurrence-Free Survival in Hormone-Sensitive Breast Cancer Patients.

Beomki Lee, Seok Jin Nam, Seok Won Kim, Jonghan Yu, Byung-Joo Chae, Se Kyung Lee, Jai Min Ryu, Jeong Eon Lee, Soo-Youn Lee

Abstract read
In one paragraph

Article in Cancer research and treatment, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Beomki LeeDepartment of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Seok Jin NamDivision of Breast Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Seok Won KimDivision of Breast Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jonghan YuDivision of Breast Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Byung-Joo ChaeDivision of Breast Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Se Kyung LeeDivision of Breast Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jai Min RyuDivision of Breast Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jeong Eon LeeDivision of Breast Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Soo-Youn LeeDepartment of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.

Funding

Korea Health Industry Development InstituteMinistry of Health and Welfare HI14C3418
6 · The paper itself

Abstract

purposeThe metabolism of tamoxifen is influenced by various cytochrome p450 enzymes, including CYP2D6 and CYP2C19, leading to variations in the levels of endoxifen, even with the same tamoxifen dose. However, the clinical significance of endoxifen for the prognosis of breast cancer patients remains controversial. This study aimed to elucidate the relevance of endoxifen level to recurrence-free survival censored with tamoxifen discontinuation (RFSt), representing the RFS for tamoxifen itself, of breast cancer patients and determine a suitable cutoff for prognostication. MATERIALS AND

methodsThe study included 478 breast cancer patients. Tamoxifen and its metabolites, including endoxifen, were measured using liquid chromatography-tandem mass spectrometry. An optimal cutoff was determined with maximally selected rank statistics. Survival analysis and Cox regression were conducted based on this cutoff.

resultsAn endoxifen level of 21.00 ng/mL was the optimal cutoff for prognostication. Survival analysis revealed a statistically significant difference in RFSt between the low endoxifen group (≤ 21.00 ng/mL) and the high endoxifen group (> 21.00 ng/mL) (log-rank test, p=0.032). The 10-year probability of RFSt was 83.2% (95% confidence interval [CI], 77.0 to 89.9) and 88.3% (95% CI, 83.3 to 93.5) in the low and high endoxifen groups, respectively. Multivariable Cox proportional hazards regression indicated endoxifen concentration as a significant factor associated with prognosis.

conclusionEndoxifen could serve as a marker for appropriate tamoxifen treatment with a cutoff of 21.00 ng/mL. Based on this cutoff, therapeutic drug monitoring would benefit patients displaying suboptimal endoxifen concentrations.

Indexed as

Antineoplastic Agents, HormonalBreast NeoplasmsTamoxifenAdultAgedDisease-Free SurvivalFemaleHumansMiddle AgedNeoplasm Recurrence, LocalPrognosisTandem Mass Spectrometry4-hydroxy-N-desmethyltamoxifenAntineoplastic Agents, HormonalTamoxifenBreast neoplasmsEndoxifenPrognosisRecurrence-free survivalTamoxifen

Identifiers

PMID38901825
PMCPMC11729306

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

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.