Tamoxifen for Breast Cancer Risk after Radiation Therapy

(LDTam Trial)

Recruiting at 12 trial locations

Age: 18+

Sex: Female

Trial Phase: Phase 2

Sponsor: University of Alabama at Birmingham

Must not be taking: Hormone therapy, Anticoagulants

Disqualifiers: Thromboembolism, Pregnancy, High creatinine, others

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

Duration: 24 months

84 Participants Needed

Trial Summary

What is the purpose of this trial?

Estrogen can cause the growth of breast cancer cells. Hormone therapy using tamoxifen citrate may fight breast cancer by blocking the use of estrogen by the tumor cells This phase IIb trial studies how well low-dose tamoxifen citrate works in reducing breast cancer risk in radiation-induced cancer survivors.

Will I have to stop taking my current medications?

The trial requires that you stop using certain medications, such as hormone replacement therapy, hormonal contraceptives, and some other hormone-related drugs, at least 6 months before joining. If you are taking warfarin or strong CYP2D6 inhibitors, you will not be allowed to participate.

What evidence supports the effectiveness of the drug Tamoxifen Citrate for reducing breast cancer risk after radiation therapy?

Research shows that adding tamoxifen to radiation therapy can improve recurrence-free survival in postmenopausal women with high-risk breast cancer, especially those with estrogen receptor-positive tumors. In one study, patients receiving both treatments had a higher recurrence-free survival rate compared to those who did not receive tamoxifen. ^{1 2 3 4 5}

Is tamoxifen safe for humans, especially after radiation therapy?

Tamoxifen has been used for over 10 years in breast cancer treatment and is generally considered safe, but it may increase the risk of endometrial cancer and cause skin side effects. Careful follow-up is necessary to monitor any potential cancer-promoting effects. ^{1 5 6 7 8}

How does the drug Tamoxifen Citrate differ from other treatments for breast cancer risk after radiation therapy?

Tamoxifen Citrate is unique because it is a hormone therapy that specifically targets estrogen receptors, which can help reduce the risk of breast cancer recurrence in patients with estrogen receptor-positive tumors. Unlike chemotherapy, which attacks cancer cells directly, Tamoxifen works by blocking estrogen from stimulating cancer cell growth, making it particularly effective for certain types of breast cancer. ^{1 5 6 9 10}

Research Team

Smita Bhatia, MD

Principal Investigator

University of Alabama at Birmingham

Eligibility Criteria

This trial is for radiation-induced cancer survivors who are at risk of breast cancer, have had chest radiation therapy by age 40, and have been disease-free for 2 years. Postmenopausal women or premenopausal women under 45 with regular periods can join. Exclusions include those with certain other cancers, recent hormone treatments, pregnancy plans within two years, or a history of blood clots.

Inclusion Criteria

I received radiation therapy in the chest area or total body irradiation of 12 Gy or more by age 40.

You have not had a period for 12 months, had surgery to remove both ovaries, or have a specific hormone level indicating you are postmenopausal.

My menopausal status is clearly defined.

Exclusion Criteria

I have signs of breast cancer on imaging but may continue if it's benign.

I have used hormone therapy or certain vaginal estrogen products recently.

Your SGOT or SGPT levels are more than double the normal range at the medical center.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive tamoxifen citrate or placebo orally once daily for 24 months

24 months

Follow-up

Participants are monitored for safety and effectiveness after treatment

Up to 10 years

Treatment Details

Interventions

• Tamoxifen Citrate

Trial Overview The study tests if low-dose tamoxifen citrate can reduce the risk of developing breast cancer in individuals previously treated with chest radiation. It involves comparing tamoxifen to a placebo and includes various assessments like mammography and questionnaires about quality of life.

Participant Groups

Group I: Arm I (tamoxifen citrate) Experimental Treatment 10 Interventions

Patients receive tamoxifen citrate PO QD for 24 months in the absence of disease progression or unacceptable toxicity.

Group II: Arm II (placebo) Placebo Group 10 Interventions

Patients receive placebo PO QD for 24 months in the absence of disease progression or unacceptable toxicity.

Who Is Running the Clinical Trial?

University of Alabama at Birmingham

Lead Sponsor

Trials

1,677

Recruited

2,458,000+

University of Washington

Collaborator

Trials

1,858

Recruited

2,023,000+

City of Hope National Medical Center

Collaborator

Trials

17

Recruited

8,900+

University of Chicago

Collaborator

Trials

1,086

Recruited

844,000+

National Cancer Institute (NCI)

Collaborator

Trials

14,080

Recruited

41,180,000+

St. Jude Children's Research Hospital

Collaborator

Trials

451

Recruited

5,326,000+

University Health Network, Toronto

Collaborator

Trials

1,555

Recruited

526,000+

University of Michigan

Collaborator

Trials

1,891

Recruited

6,458,000+

Mayo Clinic

Collaborator

Trials

3,427

Recruited

3,221,000+

Dana-Farber Cancer Institute

Collaborator

Trials

1,128

Recruited

382,000+

References

1. United States pubmed.ncbi.nlm.nih.gov

Randomized trial of adjuvant tamoxifen combined with postoperative radiation therapy or adjuvant chemotherapy in postmenopausal breast cancer. [2019]

2. United States pubmed.ncbi.nlm.nih.gov

Sequence of radiotherapy with tamoxifen in conservatively managed breast cancer does not affect local relapse rates. [2022]

3. England pubmed.ncbi.nlm.nih.gov

Radiation therapy after breast-conserving surgery; first results of a randomised clinical trial in patients with low risk of recurrence. [2022]

4. England pubmed.ncbi.nlm.nih.gov

Radiation therapy and tamoxifen after breast-conserving surgery: updated results of a 2 x 2 randomised clinical trial in patients with low risk of recurrence. [2013]

5. United States pubmed.ncbi.nlm.nih.gov

Incidence of new primary cancers after adjuvant tamoxifen therapy and radiotherapy for early breast cancer. [2019]

6. United States pubmed.ncbi.nlm.nih.gov

A Randomized Phase IIb Study of Low-dose Tamoxifen in Chest-irradiated Cancer Survivors at Risk for Breast Cancer. [2022]

7. England pubmed.ncbi.nlm.nih.gov

Radiation recall--another call with tamoxifen. [2019]

8. Germany pubmed.ncbi.nlm.nih.gov

[On the interaction of adjuvant radiotherapy and tamoxifen treatment for breast cancer]. [2013]

9. England pubmed.ncbi.nlm.nih.gov

Postoperative radiotherapy in high-risk postmenopausal breast-cancer patients given adjuvant tamoxifen: Danish Breast Cancer Cooperative Group DBCG 82c randomised trial. [2022]

10. United States pubmed.ncbi.nlm.nih.gov

Effect of conjoint administration of tamoxifen and high-dose radiation on the development of mammary carcinoma. [2019]