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Flaxseed in Preventing Breast Cancer in Premenopausal Women at Risk of Developing Breast Cancer

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ClinicalTrials.gov Identifier: NCT00794989
Recruitment Status : Terminated (low accrual)
First Posted : November 21, 2008
Last Update Posted : June 3, 2016
Information provided by (Responsible Party):
Roswell Park Cancer Institute

November 20, 2008
November 21, 2008
June 3, 2016
April 2008
June 2011   (Final data collection date for primary outcome measure)
Alteration in intermediate biomarkers of breast cancer risk at baseline and at 1, 3, and 6 months [ Time Frame: 6 months ]
Alteration in intermediate biomarkers of breast cancer risk at baseline and 1, 3, and at 6 months
Complete list of historical versions of study NCT00794989 on ClinicalTrials.gov Archive Site
Tolerability and compliance [ Time Frame: 6 months ]
Long-term tolerability and compliance
Not Provided
Not Provided
Flaxseed in Preventing Breast Cancer in Premenopausal Women at Risk of Developing Breast Cancer
A Study Evaluating the Effect of Flaxseed on Biomarkers of Breast Cancer Risk

RATIONALE: Ground flaxseed may prevent breast cancer in premenopausal women at increased risk of developing primary breast cancer.

PURPOSE: This randomized clinical trial is studying how well flaxseed works in preventing breast cancer in premenopausal women at risk of breast cancer.


Primary aims:

  • Determine if 25 grams of flaxseed supplementation daily

    • modifies proliferation (ki-67) and apoptotic rates after six months
    • modifies expression of estrogen regulated genes: Cyclin D1, survivin, and VEGF at six months
    • modifies serum IGF-1 and serum binding protein (IGFBP)-3 levels from baseline to 6 months
    • and evaluate the feasibility and tolerability of flaxseed consumption, and determine factors that lead to decreased compliance


This is a randomized study. Patients are randomized to 1 of 2 arms.

  • Arm I (intervention): Patients ingest 25 grams ground flaxseed daily, with already prepared foods, for 6 months. Patients are instructed to record the time and with what foods flaxseed is consumed, and the number of bowel movements daily. Throughout the 6-month intervention period, patients also complete unannounced telephone-administered surveys recounting all foods and beverages consumed within the previous 24 hours.
  • Arm II (observation): Patients do not receive ground flaxseed. All patients complete a diary about menstrual cycle duration and presence or improvement of premenstrual symptoms (e.g., cramping, bloating, headache, insomnia, or other irregular symptoms). Patients also complete questionnaires at 1, 3, and 6 months to access changes in diet, physical activity, menstrual history, demographic characteristics, and medical history and a specimen questionnaire at baseline and at 1, 3, and 6 months.

Blood and first-void urine samples are collected at baseline and at 1, 3, and 6 months to measure levels of lignan metabolites, flaxseed compliance, serum thiocyanate, malondialdehyde, and for biomarker studies by capillary gas chromatography-mass spectrometry, high-performance liquid chromatography, and ELISA.

After completion of study therapy, patients are followed monthly for up to 6 months.

Not Provided
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
  • Breast Cancer
  • Precancerous Condition
  • Dietary Supplement: Ground Flaxseed
    Given orally
  • Other: No Intervention
    Participants randomized to Arm 2 do not receive any intervention
  • Experimental: Arm 1: Intervention
    Patients ingest ground flaxseed daily, with already prepared foods, for 6 months.
    Intervention: Dietary Supplement: Ground Flaxseed
  • Arm 2: Observational
    Patients do not receive ground flaxseed.
    Intervention: Other: No Intervention
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
June 2011
June 2011   (Final data collection date for primary outcome measure)
  • Patients enrolled in must meet ≥ 1 of the following criteria:

    • History of unilateral or bilateral atypical ductal hyperplasia with or without family history
    • History of atypical lobular hyperplasia or lobular carcinoma in situ with or without family history
    • History of ductal carcinoma in situ
    • Prior stage I breast cancer allowed provided it was adequately treated and therapy was completed ≥ 1 year ago
    • Lifetime risk for developing breast cancer > 20% (based on Gail or Claus model)
    • No abnormal mammogram requiring short-term follow-up within the past 6 months
    • No severe atypia or carcinoma cells on RPRNA


  • Premenopausal
  • ECOG performance status 0-1
  • Patients enrolled must meet the following criteria:

    • No peri- or postmenopausal status as determined by estradiol levels < 20 ng/dL and FSH levels > 45 ng/dL
    • No thrombocytopenia (defined as platelet count < 50,000/mm^3)
    • Creatinine ≤ 1.5 mg/dL
    • Not pregnant or nursing
    • Fertile patients must use effective contraception consistently
    • No other prior malignancy allowed except for the following:

      • Basal cell or squamous cell carcinoma
      • In situ cervical cancer
    • No history of any of the following conditions within the past 5 years:

      • Crohn disease
      • Ulcerative colitis
      • Inflammatory bowel disease
      • Irritable bowel syndrome
      • Celiac sprue
      • Malabsorption syndrome
      • Diverticulitis
      • Diverticulosis
    • No allergy to flaxseed, other seeds or nuts, or wheat


  • Patients enrolled in part 1 must meet the following criteria:

    • No prior breast implants or tram-flap reconstruction

      • Breast reduction allowed
    • No prior neoadjuvant chemotherapy or other chemotherapy within the past year
    • No prior neoadjuvant hormonal therapy
    • No prior whole radiation to the contralateral breast undergoing random periareolar fine needle aspiration (RPFNA)
    • No concurrent coumadin or other chronic anticoagulants (even if they are held for surgery)
  • Patients enrolled in part 2 must meet the following criteria:

    • More than 1 year since prior chemotherapy and adjuvant hormonal therapy for breast cancer

      • No concurrent chemotherapy for breast cancer
    • At least 1 month since prior and no concurrent treatment with corticosteroid
    • At least 2 weeks since prior and no concurrent use of antibiotics
    • At least 2 weeks
    • No history of chest wall irradiation
    • No presence of breast implants
    • No prior or concurrent tamoxifen within the past 90 days
    • No chronic/concurrent medications that inhibit platelet function, including any of the following:

      • Aspirin
      • Non-steroidal anti-inflammatory drugs (i.e., Aleve®, Motrin®, ibuprofen)
      • Coumadin
      • Heparin
      • Low molecular weight heparin
      • Anti-platelet agents

        • No prior short-term use of platelet inhibitors ≥ 7 days prior to RPFNA
    • No concurrent ingestion of the following:

      • Pumpkin seeds
      • Sesame seeds
      • Fish oil supplements
    • At least 30 days since prior and no concurrent flaxseed supplements, fish oil, or flaxseed oil
    • No concurrent treatment for another malignancy
Sexes Eligible for Study: Female
21 Years to 50 Years   (Adult)
Contact information is only displayed when the study is recruiting subjects
United States
I 81906
RPCI-I-81906 ( Other Identifier: Roswell Park Cancer Institute )
11-0575 ( Other Identifier: University of Chicago )
Not Provided
Not Provided
Roswell Park Cancer Institute
Roswell Park Cancer Institute
Not Provided
Principal Investigator: Swati Kulkarni, M.D. University of Chicago
Roswell Park Cancer Institute
June 2016

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP