Drug Withdrawal in Women With Progressive Breast Cancer While on Aromatase Inhibitor Therapy

Breast Cancer Clinical Trial

Official title: A Phase II Clinical Trial of Drug Withdrawal in Women With Progressive Breast Cancer While on Aromatase Inhibitor Therapy

Status Completed

Clinical Trial Summary

The purpose of this research study is to study the effects of stopping aromatase inhibitory (AI) therapy on breast cancer progression. Aromatase inhibitors are a class of drugs used to treat breast cancer in postmenopausal women. They work by decreasing the level of estrogen, which is believed to stimulate the growth of tumor tissue. Breast cancer that progresses despite therapy with an AI is thought to have been resistant to AI therapy. There is scientific evidence to suggest that resistant breast cancer cells learn to grow at the very low levels of estrogen present on AI therapy and that increasing estrogen levels even slightly by stopping AI therapy with inhibit the breast cancer cells. An improvement or stabilization of breast cancer has been observed after stopping therapy with tamoxifen, a different anti-estrogen therapy, and has been reported in the literature after stopping AI therapy. This research study will be the first study to formally test the rate of disease improvement (response) or stabilization after stopping AI therapy.

Clinical Trial Description

• Participants will have the following tests and procedures done at 8 weeks, 16 weeks, and 24 weeks after stopping AI therapy: Physical examination; blood tests; tumor assessment by physical exam (if possible); chest x-ray or CT scan of chest; CT scans of abdomen and pelvis; and bone scan.

• After week 24, these procedures will be repeated every 12 weeks while the participant is on the study. ;

Study Design

Observational Model: Case-Only, Time Perspective: Prospective

Related Conditions & MeSH terms

• Breast Cancer
• Breast Neoplasms
• Substance Withdrawal Syndrome

• NCT number: NCT00916162
• Study type: Observational
• Source: Massachusetts General Hospital
• Status: Completed
• Phase: N/A
• Start date: August 2006
• Completion date: January 2010