Oral Tamoxifen vs. TamGel vs. Control in Women With Atypical Hyperplasia or Lobular Carcinoma In Situ

Overview

About this study

The purpose of this study is to analyze breast tissue changes after a short course of Tamoxifen (Tam).

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

- Willing to return to enrolling institution for follow-up

- Willing to complete required testing

- Ability to complete questionnaire by themselves or with assistance

- Female (sex that was assigned at birth)

- Ipsilateral intact breast with histology confirmation of atypical ductal or lobular
hyperplasia, or LCIS, within the last 5 years, whether surgically excised or not.

- Eastern Cooperative Oncology Group (ECOG) performance status ≤1

- The effects of topical afimoxifene (4-OHT) gel on the developing human fetus at the
recommended therapeutic dose are unknown. However, oral tamoxifen is Pregnancy
Category D-positive evidence of human fetal risk. For this reason, and because
triphenylethylene antiestrogens, including tamoxifen, are known to be teratogenic,
women of childbearing potential and their male partners must agree to use at least one
effective form of birth control (abstinence is not an allowed method) prior to study
entry and for the duration of study participation, and for 2 months following the last
dose of study medications (participant can resume oral birth control pills for
effective birth control measures after post-treatment biopsy is done). Effective birth
control methods during treatment are: copper and Mirena intrauterine device (IUD),
diaphragm/cervical cap/shield, spermicide, contraceptive sponge, condoms. Tubal
Ligation is an acceptable method of birth control. Women of childbearing potential
must have a negative pregnancy test within five days before starting study
medications. Should a woman become pregnant or suspect she is pregnant while
participating in this study, she should inform her study physician immediately.

- Willingness to avoid exposing breast skin to natural or artificial sunlight (i.e.
tanning beds) for the duration of the study.

- Participants must have acceptable organ and marrow function as judged by treating
physician's evaluation of baseline laboratory data.

- Negative pregnancy (serum or urine) test if of childbearing potential and/or follicle
stimulating hormone (FSH) to verify menopausal status.

Exclusion Criteria:

- Clinically suspicious mass/lesions

- Breast cancer in the past 5 years.

- Patients with any history of venous thromboembolic disease, regardless of timeframe
(history of varicose veins and superficial phlebitis is allowed).

- Cytotoxic chemotherapy for any indication in last 2 years.

- Current pregnancy or lactation.

- History of other prior breast cancer-specific therapy within the previous 2 years
(chemotherapy, anti-HER2 agents, endocrine agents, everolimus, CDK4-6 inhibitors).

- Cytotoxic chemotherapy for any indication in last 2 years.

- Prior use of selective estrogen receptor modulator (SERMS) or AIs including tamoxifen,
raloxifene, anastrozole, letrozole, or exemestane for prevention or therapy within 5
years.

- Exogenous sex steroid, including oral contraceptive pill use within 1 month prior to
pretreatment breast biopsy. Use of vaginally administered estrogens and hormone coated
IUD such as Mirena is permitted.

- History of any prior ipsilateral breast radiotherapy. Previous unilateral radiation of
the contralateral side is allowed.

- Skin lesions on the breast that disrupt the stratum corneum (e.g., eczema,
ulceration).

- History of endometrial neoplasia

- Current smoker. Cessation for at least 6 weeks

- Current users of potent inhibitors of tamoxifen metabolism. The potent inhibitors of
tamoxifen metabolism are: bupropion, cinacalcet, fluoxetine, paroxetine, quinidine.

- Participants may not be receiving any other investigational agents within 90 days of
enrollment or during this study.

- History of allergic reactions to tamoxifen.

- Uncontrolled intercurrent illness that in the judgement of the treating physician
would make them unsuitable for study participation

- Current use of anticoagulation medications.

- Patients who are breastfeeding.

- Hemoglobin < 10 g/dL (within 30 days of randomization).

- Leukocytes < 3,000/microliter (within 30 days of randomization).

- Platelets < 100,000/microliter (within 30 days of randomization).

- Total bilirubin > 1.5 x institutional upper limit of normal (ULN) (within 30 days of
randomization).

- Aspartate aminotransferase (AST) serum glutamic oxaloacetic transaminase (SGOT) > 1.5
x ULN (within 30 days of randomization).

- Alanine aminotransferase (ALT) serum glutamate pyruvate transaminase (SGPT) > 1.5 x
ULN (within 30 days of randomization).

- Alkaline phosphatase, S > 1.5 x ULN (within 30 days of randomization).

- Albumin, S > 1.5 x ULN (within 30 days of randomization).

- Protein, total, S > 1.5 x ULN (within 30 days of randomization).

- Creatinine > 1.5 x ULN (within 30 days of randomization).

- Patients who are taking any medications, herbal products, or over the counter (OTC)
products that are moderate or strong CYP2D6 inhibitors or CYP3A inducers. Patients
should also refrain from starting any drug or product with these properties during the
study. This is to avoid any potential interactions with tamoxifen or 4-OHT.

- Identification of a clinically suspicious mass on examination.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 2/12/2024. Questions regarding updates should be directed to the study team contact.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Amy Degnim, M.D.

Closed for enrollment

Contact information:

Denice Gehling R.N., CCRP

(507) 538-1628

Gehling.Denice@mayo.edu

More information

Publications

Publications are currently not available

Additional contact information

Cancer-related trials contact form

Phone: 855-776-0015 (toll-free)

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