Study of Changes in Estrogen Levels and Grip Strength in Postmenopausal Women Who Have Received 4 to 6 Years of Hormone Therapy for Breast Cancer and Are Currently Receiving Letrozole on Clinical Trial IBCSG-35-07
Condition: Breast Cancer
MeSH terms: Breast Neoplasms
Study type: Observational

Summary: 
      RATIONALE: Studying samples of blood in the laboratory from patients receiving treatment for
      cancer may help doctors learn more about changes that may occur in DNA and identify
      biomarkers related to cancer.

      PURPOSE: This clinical trial is studying changes in estrogen levels and grip strength in
      postmenopausal women who have received 4 to 6 years of hormone therapy for breast cancer and
      are currently receiving letrozole on clinical trial IBCSG-35-07.
    

Detailed description: 
      OBJECTIVES:

      Primary

        -  To determine the serum level of estrogens (Estradiol [E2], Estrone [E1], and Estrone
           Sulphate [E1S] and sex hormone binding globulin [SHBG]) in postmenopausal women with
           prior endocrine-responsive, node-positive, resectable breast cancer completing 4 to 6
           years of adjuvant endocrine therapy and enrolled on clinical trial IBCSG-35-07 receiving
           letrozole.

        -  To determine the degree of recovery of E2, E1, and E1S during the 3-month letrozole-off
           gap.

      Secondary

        -  To determine the association between estrogen level changes and the clinical outcomes of
           toxicity and quality of life.

        -  To determine the effect of prior adjuvant endocrine therapy, age, body mass index, and
           type of menopause on estrogen levels.

        -  To determine the variability of estrogen level changes and its association with germline
           single nucleotide polymorphisms.

        -  To examine changes in grip-strength score.

      OUTLINE: This is a multicenter study.

      All patients undergo blood sample collection at baseline for the analysis of single
      nucleotide polymorphisms, after randomization on clinical trial IBCSG-35-07 and prior to the
      beginning treatment on IBCSG-35-07. Patients also undergo serum collection at baseline and at
      9, 10.5, and 12 months for the analysis of estrogen levels and sex hormone binding globulins.
      Patients undergo measurement of grip strength at baseline and at 9 and 12 months. Samples may
      be banked for future research studies.

      Patients complete quality-of-life questionnaires (Breast Cancer Prevention Trial [BCPT]
      Symptom Scales on Form 35-PRS and IBCSG Trial 35-07 QL Form) periodically.
    

Intervention name(s): polymorphism analysis; laboratory biomarker analysis; quality-of-life assessment
Intervention type(s): Genetic; Other; Procedure
Intervention description(s): SNPs will be genotyped in whole blood samples taken at baseline.; Biomarkers will be assessed in blood and serum samples at different time points.; Quality of life will be assessed using the Breast Cancer Prevention Trial (BCPT) Symptom Scales and the IBCSG Trial 35-07 QL Form.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients randomized to the SOLE trial (IBCSG 35-07) and participate in the Quality of Life
        substudy.
      
Biospecimen description: 
      Serum, whole blood,
    
Keywords: stage IA breast cancer; stage IB breast cancer; stage II breast cancer; stage IIIA breast cancer