Impact of Aromatase Inhibitor Therapy on Glucose Homeostasis and Diabetes Risk

This study assesses the effect of hormone directed treatment for breast cancer on glucose metabolism.

Study Overview

• Status: Recruiting
• Conditions: HER2-Positive Breast Carcinoma
• Intervention / Treatment: Other: Non-Interventional Study

Detailed Description

PRIMARY OBJECTIVE:

I. Assess the impact of endocrine adjuvant therapy with aromatase inhibitors in women with hormone receptor positive breast cancer, ductal carcinoma in situ (cancer, DCIS ), or women with other high risk breast conditions, on various indices of glucose homeostasis, utilizing oral minimal model assessment, in comparison to healthy post menopausal women and another cohort of women on tamoxifen.

OUTLINE: This is an observational study.

Patients undergo blood sample collection, glucose testing, dual-energy x-ray absorptiometry (DEXA) scan to measure body composition, complete a questionnaire and have their medical records reviewed on study.

• Study Type: Observational
• Enrollment (Estimated): 66

Contacts and Locations

• Study Contact: Name: Clinical Trials Referral Office; Phone Number: 855-776-0015; Email: mayocliniccancerstudies@mayo.edu

Study Locations

• United States
  • Minnesota
    • Rochester, Minnesota, United States, 55905
      • Recruiting
      • Mayo Clinic in Rochester
      • Contact: Clinical Trials Referral Office; Phone Number: 855-776-0015; Email: mayocliniccancerstudies@mayo.edu
      • Principal Investigator: Kalpana Muthusamy, MBBS, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Post-menopausal women with hormone receptor positive breast cancer, DCIS, or other high risk breast conditions who are planning to start or within 6 months of starting treatment with an aromatase inhibitor or tamoxifen and healthy post-menopausal women.

Description

Inclusion Criteria:

• Post-menopausal women with hormone receptor positive breast cancer, ductal carcinoma in situ (DCIS), or with other high risk breast conditions. Post-menopause will be defined as women who experience 12 months of amenorrhea or have undergone bilateral salpingo-oophorectomy.

  • 25 women who are planning to start or are within 6 months of starting treatment with aromatase inhibitors, after consultation in breast clinic and cancer center.
  • 25 women who will be starting Tamoxifen (comparative group)
  • 25 healthy post menopausal women will also be recruited.

Exclusion Criteria:

• Established diagnosis of diabetes
• Therapy with medications that could affect glucose metabolism
• Screening fasting glucose ≥ 126 mg/dl, and/or HbA1c ≥ 6.5%
• History of upper GI surgery that alters gastric emptying or causing malabsorption e.g., bariatric surgery, fundoplication

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Observational; Patients undergo blood sample collection, glucose testing, DEXA scan to measure body composition, complete a questionnaire and have their medical records reviewed on study.	Other: Non-Interventional Study; Non-Interventional Study

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glucose homeostasis - tamoxifen compared to no treatment	Glucose homeostasis is the process by which the body regulates blood glucose levels, also known as blood sugar, within a narrow range. Glucose homeostasis of women with hormone receptor positive breast cancer or DCIS treated with tamoxifen will be compared to glucose homeostasis of women without treatment. Participants will undergo a history, physical examination, and a blood collection for fasting glucose, and Hemoglobin A1C (HbA1c) at baseline and one year later. Participants will be contacted at 3 and 6 months by phone to confirm continued use of the endocrine therapy that was initiated by the clinical team.	Baseline; up to 1 year
Glucose homeostasis - aromatase inhibitor compared to tamoxifen	Glucose homeostasis is the process by which the body regulates blood glucose levels, also known as blood sugar, within a narrow range. Glucose homeostasis of women with hormone receptor positive breast cancer or DCIS treated with aromatase inhibitors will be compared to glucose homeostasis of women treated with tamoxifen. Participants will undergo a history, physical examination, and a blood collection for fasting glucose, and Hemoglobin A1C (HbA1c) at baseline and one year later. Participants will be contacted at 3 and 6 months by phone to confirm continued use of the endocrine therapy that was initiated by the clinical team.	Baseline; up to 1 year
Disposition Index (DI)	Will be calculated as the product of beta cell responsivity and Si (insulin action). DI of women with hormone receptor positive breast cancer or DCIS treated with aromatase inhibitors will be compared to DI of healthy post menopausal women. Participants will undergo a history, physical examination, and a blood collection for fasting glucose, and Hemoglobin A1C (HbA1c) at baseline and one year later. Participants will be contacted at 3 and 6 months by phone to confirm continued use of the endocrine therapy that was initiated by the clinical team.	Baseline; up to 1 year

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Investigators: Principal Investigator: Kalpana Muthusamy, MBBS, MD, Mayo Clinic in Rochester

Publications and helpful links

Helpful Links

• Mayo Clinic Clinical Trials

Study record dates

Study Major Dates

• Study Start (Actual): November 16, 2023
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: August 13, 2024
• First Submitted That Met QC Criteria: August 13, 2024
• First Posted (Actual): August 16, 2024

Study Record Updates

• Last Update Posted (Actual): March 31, 2026
• Last Update Submitted That Met QC Criteria: March 26, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Skin Diseases; Neoplasms; Neoplasms by Site; Breast Diseases; Breast Neoplasms
• Other Study ID Numbers: 23-005595 (Mayo Clinic in Rochester); NCI-2024-01190 (Registry Identifier: CTRP (Clinical Trial Reporting Program))

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No