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NCT07833501Not yet recruiting

Estradiol Levels According to Body Mass Index in Premenopausal Patients With Breast Cancer

Evaluation of Serum Estradiol Levels According to Body Mass Index Categories in Premenopausal Patients With Hormone Receptor-Positive Breast Cancer Receiving Aromatase Inhibitors and Pharmacologic Ovarian Suppression

Source: ClinicalTrials.gov · Last updated 22 Sept 2026

Brief summary (registry, in English)

his prospective observational study will evaluate whether body mass index (BMI) is associated with serum estradiol levels in premenopausal women with hormone receptor-positive breast cancer. Participants will already be receiving standard adjuvant treatment with an aromatase inhibitor and pharmacologic ovarian suppression as part of their routine clinical care. The study will not assign or modify cancer treatment. Approximately 172 participants will be enrolled at multiple study sites in Brazil. They will be classified into two main groups: normal BMI and overweight or obesity. Clinical information, medication use, physical activity, weight, height, and serum estradiol levels will be recorded. Estradiol will be measured using an ultrasensitive laboratory method, with the main assessment occurring after approximately three months of treatment. The primary objective is to compare the proportion of participants with serum estradiol levels above 2.72 pg/mL between the two BMI groups. The study will also examine the relationship between BMI and absolute estradiol levels and explore whether clinical characteristics, previous chemotherapy, physical activity, or use of glucagon-like peptide-1 receptor agonists are associated with inadequate estrogen suppression.

Status (registry)
Not yet recruiting
Study type
Observational
Enrollment
172 (estimated)
First submitted
16 Sept 2026
Start date
3 Sept 2026
Primary completion date
30 Dec 2026
Lead sponsor
D'Or Institute for Research and Education
NCT number
NCT07833501

What you commit to

  • Study type: Observational
  • Planned participants: 172
  • From 3 Sept 2026 to the primary completion date, 30 Dec 2026
  • No sites listed in no country
  • Visits and tests: ask the trial team, the registry does not list them

Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.

Who cannot take part

Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.

Prior treatment

  • Concomitant use of medications known to interfere with estradiol metabolism or measurement, including systemic corticosteroids at supraphysiologic doses.
  • Concurrent participation in another clinical study that may interfere with the hormonal outcomes evaluated in this study.

Other illness

  • Postmenopausal status at the initiation of endocrine therapy. Known endocrine disorders that may interfere with the production or metabolism of sex steroids.

Lab values

  • Metastatic disease at enrollment. Technical or logistical inability to undergo serum estradiol measurement using an ultrasensitive laboratory method.

Who the study is looking for

  • Female sex. Age 18 years or older. Histologically confirmed hormone receptor-positive invasive breast cancer, defined as estrogen receptor-positive and/or progesterone receptor-positive disease, regardless of human epidermal growth factor receptor 2 status.
  • Premenopausal status at the initiation of ovarian suppression, as determined by menstrual history and/or laboratory criteria according to medical assessment.
  • Indication for adjuvant treatment with an aromatase inhibitor (anastrozole, letrozole, or exemestane) combined with pharmacologic ovarian suppression using a gonadotropin-releasing hormone analog.
  • Continuous use of an aromatase inhibitor and a gonadotropin-releasing hormone analog for at least 3 months before the primary study assessment.
  • Documented body mass index at enrollment. Ability to understand the study information and provide written informed consent.

Age in the registry: 18 years to - · Sex: Female · Accepts healthy volunteers

Full criteria on ClinicalTrials.gov

This page is information, not medical advice. Discuss any trial with your doctor.