Evidence map›Paper›PMID 37067610›Full record

ArticleBreast cancer research and treatment2023

Tamoxifen pharmacokinetics and pharmacodynamics in older patients with non-metastatic breast cancer.

E T D Souwer, A Sanchez-Spitman, D J A R Moes, H Gelderblom, J J Swen, J E A Portielje, H J Guchelaar, T van Gelder

Open access · hybridAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Breast cancer research and treatment, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
1.9field-weighted citation impact, top 13% of its field
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

2 citing papers in PubMed, 6 citations in OpenAlex.

  1. Article
  2. Article
4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

8 authors at 1 institution in 1 country.

E T D SouwerDepartment of Medical Oncology, Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300 RC, Leiden, The Netherlands. e.t.d.souwer@lumc.nl.ORCID http://orcid.org/0000-0003-0489-7321
A Sanchez-SpitmanDepartment of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
D J A R MoesDepartment of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
H GelderblomDepartment of Medical Oncology, Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300 RC, Leiden, The Netherlands.
J J SwenDepartment of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
J E A PortieljeDepartment of Medical Oncology, Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300 RC, Leiden, The Netherlands.
H J GuchelaarDepartment of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
T van GelderDepartment of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
Leiden University Medical Center · NL

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundWe aimed to study the pharmacokinetics and -dynamics of tamoxifen in older women with non-metastatic breast cancer.

methodsData for this analysis were derived from the CYPTAM study (NTR1509) database. Patients were stratified by age (age groups < 65 and 65 and older). Steady-state trough concentrations were measured of tamoxifen, N-desmethyltamoxifen, 4-hydroxy-tamoxifen, and endoxifen. CYP2D6 and CYP3A4 phenotypes were assessed for all patients by genotyping. Multiple linear regression models were used to analyze tamoxifen and endoxifen variability. Outcome data included recurrence-free survival at time of tamoxifen discontinuation (RFSt) and overall survival (OS).

results668 patients were included, 141 (21%) were 65 and older. Demographics and treatment duration were similar across age groups. Older patients had significantly higher concentrations of tamoxifen 129.4 ng/ml (SD 53.7) versus 112.2 ng/ml (SD 42.0) and endoxifen 12.1 ng/ml (SD 6.6) versus 10.7 ng/ml (SD 5.7, p all < 0.05), independently of CYP2D6 and CYP3A4 gene polymorphisms. Age independently explained 5% of the variability of tamoxifen (b = 0.95, p < 0.001, R

conclusionSerum concentrations of tamoxifen and its demethylated metabolites are higher in older patients, independent of CYP2D6 or CYP3A4 gene polymorphisms. A higher bioavailability of tamoxifen in older patients may explain the observed differences. However, clinical relevance of these findings is limited and should not lead to a different tamoxifen dose in older patients.

Indexed as

Antineoplastic Agents, HormonalBreast NeoplasmsCytochrome P-450 CYP2D6Cytochrome P-450 CYP3AFemaleGenotypeHumansTamoxifen4-hydroxy-N-desmethyltamoxifenAntineoplastic Agents, HormonalCytochrome P-450 CYP2D6Cytochrome P-450 CYP3ATamoxifenAdjuvant treatmentBreast cancerPharmacodynamicPharmacokineticsTamoxifenTherapeutic drug monitoring

Identifiers

PMID37067610
PMCPMC10175413
OpenAlexW4366083543

What OpenQuestion holds

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LicenceCC BY
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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.