Research Radartracking 1,138 published studies · 277 human · 6 safety signals · 42 clinical trials · 44 cancer pages · updated Jul 2026Open the Research Map →

Tamoxifen

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Human-reviewed · How we review →

AI extractedhuman reviewedsources checkedretractions suppressed

Evidence at a glanceHuman · observationalMixed results
3 published studies tagged to this agent1 human studies approved & graded (trial, observational, or meta-analysis)
Why this grade?

Human · observationalHuman observational evidence only — no trials.

Computed deterministically from the studies’ types and reported outcomes — not written by AI, and not a claim that anything works.

Auto-discovered · not yet curatedtamoxifen
Educational only, not medical advice. OncoForge makes no claim that Tamoxifen treats, prevents, or cures any condition, beyond what the linked studies show. Evidence levels vary; effects may not translate to people, and some compounds can cause harm. Always coordinate with your oncology team.

Simple Summary

Auto-discovered from 1 recent study; not yet curated.

Research

Where the evidence is

What has been studied, and how strong it is, by topic. A dashed cell means no studies were found for that combination — a gap, not evidence of no effect. Open a row to see its studies.

CancerHuman evidenceMechanismSafetyTrial
Endometrial Carcinosarcoma11
Uterine Carcinosarcoma (Malignant Mixed MüLlerian Tumor)11
Advanced Or Metastatic High Grade Epithelial Ovarian Cancer11
Breast Cancer1
Endometrial Cancer1
High Grade Epithelial Ovarian Cancer11
Ovarian Epithelial Carcinoma11

Reported figures

Study mix

3 published studies by what they were done in. Lab and animal findings often do not carry over to people.

1 Human2 Review/other
Reported directionMixed results1Inconclusive2

What supports this page

The kinds of sources behind this page, strongest at the top. Faint rungs show what is not here yet.

Guideline
0
Meta-analysis
0
Systematic review
0
Randomized trial
0
Clinical trial
0
Observational
1
Case report
0
Review
2
Preclinical
0
Other
0
3 studies1 human2 review/other

Tracking 3 published studies of Tamoxifen: 1 in humans, 2 reviews/other.

Reported direction across studies: 1 mixed, 2 inconclusive.

These counts summarize what the studies reported; they are not a measure of whether Tamoxifen works.

Cancers named in these studies

advanced or metastatic high-grade epithelial ovarian cancer (1)high-grade epithelial ovarian cancer (1)ovarian epithelial carcinoma (1)endometrial cancer (1)breast cancer (1)uterine carcinosarcoma (malignant mixed Müllerian tumor) (1)endometrial carcinosarcoma (1)

All studies

ReviewTrialInconclusiveLimited evidenceTier 4 · clinicaln = 11

Expert consensus: Profiling and management of advanced or metastatic epithelial ovarian cancer

Revista colombiana de obstetricia y ginecologia · Jun 2024 · expert consensus / practice guideline based on literature review

BevacizumabAnastrozoleCisplatinGemcitabineTopotecanOlaparibNiraparibCarboplatinLiposomal-doxorubicinPaclitaxelTamoxifenRucaparibadvanced or metastatic high-grade epithelial ovarian cancerhigh-grade epithelial ovarian cancerovarian epithelial carcinoma

This paper is an expert consensus, not a clinical study of a single drug. Eleven specialists reviewed the literature and issued recommendations for managing advanced or metastatic high-grade epithelial ovarian cancer, including surgery, chemotherapy, genetic testing, bevacizumab, and PARP inhibitors. It does not report new patient outcomes from a trial. The document mainly summarizes what the panel suggested based on existing guidelines and evidence.

Studied with: platinum-based chemotherapy, bevacizumab, paclitaxel, carboplatin.

Key findings
  • The panel suggested primary cytoreductive surgery as the initial approach when complete resection is feasible.
  • Neoadjuvant chemotherapy followed by interval surgery was suggested when complete cytoreduction is unlikely or the patient has poor functional status/comorbidities.
  • Bevacizumab was suggested with platinum-based chemotherapy for high-risk disease, with maintenance only if it was part of first-line therapy.
  • PARP inhibitors (olaparib, niraparib, rucaparib) were suggested as maintenance in selected BRCA/HRD-defined groups.
  • For platinum-resistant relapse, sequential non-platinum single-agent chemotherapy and best supportive care for poor performance status were suggested.
Limitations: This is a consensus statement/practice guideline, not an original comparative trial.; No new efficacy or safety data are reported in the abstract.; Recommendations are based on literature review and expert agreement, so they are subject to guideline-selection and expert-opinion bias.; The abstract does not provide patient-level outcomes, follow-up, or effect estimates.; Several recommendations are conditional/suggested rather than based on direct evidence from this paper..

Provides management recommendations for advanced/metastatic epithelial ovarian cancer, including several anticancer agents and maintenance strategies.

AI summary of the abstract, human-reviewed · Jun 2026. Describes what this study reported, not medical advice. View on PubMed · Full text

ReviewMixed resultsModerate evidenceTier 3 · early human

Tamoxifen and Endometrial Cancer: A Janus-Headed Drug

Cancers · Sep 2020 · narrative review

Tamoxifenendometrial cancerbreast cancer

This narrative review summarizes evidence that tamoxifen both increases the risk of endometrial cancer (estimated about 2–7 fold) and can have therapeutic activity in advanced or recurrent endometrial cancer with low toxicity. The authors discuss mechanistic explanations for these opposing effects, including tissue-specific ERα co-activator/co-repressor profiles and agonism at the membrane estrogen receptor GPER-1. The review does not present new primary data.

Reported effect: endometrial cancer risk (fold increase)

Key findings
  • Tamoxifen is used for treatment and prevention of ER-positive breast cancer.
  • Tamoxifen increases the risk of endometrial cancer by about 2-7 fold, and more aggressive types of EC with poor prognoses are observed in tamoxifen users.
  • Tamoxifen can be an efficacious treatment for advanced or recurrent endometrial cancer with low toxicity.
  • Differential agonist versus antagonist effects in endometrium are explained by tissue-specific expression of ERα co-activators and co-repressors and by tamoxifen acting as a pure agonist at GPER-1.
Limitations: Narrative review: no new primary data or pooled quantitative synthesis presented in the abstract.; Abstract does not state literature search or selection methods (potential selection bias).; Mechanistic explanations are proposed based on prior literature but not experimentally demonstrated within this article..

AI summary of the abstract, human-reviewed · Jun 2026. Describes what this study reported, not medical advice. View on PubMed · Full text

Human · observationalSafetyInconclusiveLimited evidenceTier 3 · early humann = 21

Is there an association between long-term tamoxifen treatment and the development of carcinosarcoma (malignant mixed Müllerian tumor) of the uterus?

International journal of gynecological cancer : official journal of the International Gynecological Cancer Society · Jul 1995 · retrospective case series / archive review (single-center)

Tamoxifenuterine carcinosarcoma (malignant mixed Müllerian tumor)endometrial carcinosarcoma

The authors report a cluster of five uterine carcinosarcoma cases in 1993 at their center, four of whom had been prescribed long-term tamoxifen for breast cancer. A review of archives from 1983-1992 found two additional tamoxifen-associated carcinosarcoma cases among 16 total cases. In total six patients with carcinosarcoma had been taking tamoxifen; five had been on the drug at least six years and one had a three-year history. The authors raise the question of a possible association between long-term tamoxifen use and development of endometrial carcinosarcoma.

Reported effects: 1993 cluster cases 5 · 1993 cluster tamoxifen-associated cases 4 · +5 more

Key findings
  • A cluster of five patients with endometrial carcinosarcoma occurred at the center during 1993; four of these had been prescribed long-term tamoxifen for breast carcinoma.
  • Archive review for 1983-1992 revealed two further cases of uterine carcinosarcoma occurring in patients prescribed tamoxifen, from a total of 16 cases of this tumor.
  • Five of the six patients diagnosed with carcinosarcoma who had been taking tamoxifen had been maintained on the drug for at least 6 years; the other had a 3-year history of tamoxifen therapy.
  • The authors raise the question of an association between long-term tamoxifen treatment and development of endometrial carcinosarcoma following increased prescribing after 1984.
Limitations: Small number of cases (cluster and a few archival cases).; Single-center, retrospective, descriptive case series without a control group or denominator of tamoxifen-exposed patients.; No statistical analysis or incidence rates provided to quantify risk.; Potential reporting and selection bias; confounding factors not addressed (e.g., underlying breast cancer population)..

AI summary of the abstract, human-reviewed · Jun 2026. Describes what this study reported, not medical advice. View on PubMed

What changed recently

The latest additions to Tamoxifen's evidence base, and anything that's been retracted.

Recently added

Evidence at a glance: Tamoxifen by cancer

A deterministic grade of what published studies report for each: strength of evidence, the reported direction, and the largest credible effect, strongest-evidence first. This summarizes findings; it is not a claim that anything works.

Endometrial carcinosarcomaHuman · observationalInconclusive1 human

Human observational evidence only — no trials.

Largest credible effect: 1993 cluster cases 5 PMID 11578496 · effect sizes 2–16 across 7 studies

Most authoritative study: Is there an association between long-term tamoxifen treatment and the development of carcinosarcoma (malignant mixed Müllerian tumor) of the uterus?

Based on a single study.
Uterine carcinosarcoma (malignant mixed Müllerian tumor)Human · observationalInconclusive1 human

Human observational evidence only — no trials.

Largest credible effect: 1993 cluster cases 5 PMID 11578496 · effect sizes 2–16 across 7 studies

Most authoritative study: Is there an association between long-term tamoxifen treatment and the development of carcinosarcoma (malignant mixed Müllerian tumor) of the uterus?

Based on a single study.
Advanced or metastatic high-grade epithelial ovarian cancerInsufficient evidenceInconclusive

No primary experimental studies yet.

Most authoritative study: Expert consensus: Profiling and management of advanced or metastatic epithelial ovarian cancer

No human studies yet · No numeric effect sizes reported · Based on a single study.
Breast cancerInsufficient evidenceMixed results

No primary experimental studies yet.

Most authoritative study: Tamoxifen and Endometrial Cancer: A Janus-Headed Drug

No human studies yet · No numeric effect sizes reported · Based on a single study.
Endometrial cancerInsufficient evidenceMixed results

No primary experimental studies yet.

Most authoritative study: Tamoxifen and Endometrial Cancer: A Janus-Headed Drug

No human studies yet · No numeric effect sizes reported · Based on a single study.
High-grade epithelial ovarian cancerInsufficient evidenceInconclusive

No primary experimental studies yet.

Most authoritative study: Expert consensus: Profiling and management of advanced or metastatic epithelial ovarian cancer

No human studies yet · No numeric effect sizes reported · Based on a single study.
Ovarian epithelial carcinomaInsufficient evidenceInconclusive

No primary experimental studies yet.

Most authoritative study: Expert consensus: Profiling and management of advanced or metastatic epithelial ovarian cancer

No human studies yet · No numeric effect sizes reported · Based on a single study.

Dose: as studied, not a recommendation

These are doses as studied or reported, never a recommendation. The right amount of Tamoxifen depends on you, your other medicines, and your situation; decide it with your oncology team and pharmacist, not from a web page.
Doses reported in studies

Clinical trials studying Tamoxifen

1 ongoing · 2 completed · tracked from ClinicalTrials.gov. Recruiting is not the same as proven, and completed is not the same as positive — read the results. Not a recommendation.

Completed

Search all trials on ClinicalTrials.gov →

Inclusion here is not an endorsement. OncoForge makes no claim beyond what the linked studies show. Discuss anything on this page with your oncology team before acting on it.

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