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Medication Switch versus Guideline-directed Intervention (Side Effect Management) in Reducing Side Effects of Aromatase Inhibitors in Estrogen Receptor Positive HER2 Negative Breast Ductal Carcinoma In Situ and Stage I-III Invasive Breast Cancer, SWIVEL Trial

Trial Status: active

This phase II trial compares the effect of changing (or switching) aromatase inhibitors (AI) to a guideline-directed intervention, standard side effect treatment, in managing side effects in patients with estrogen receptor positive and HER2 negative breast ductal carcinoma in situ (DCIS) and stage I-III invasive breast cancer. Estrogen can cause the growth of breast cancer cells. AIs, such as letrozole, anastrozole, and exemestane, are a type of hormone therapy that lowers the amount of estrogen by blocking an enzyme in fat tissue called aromatase, which changes other hormones in the body to estrogen. This may help stop the growth of tumor cells that need estrogen to grow. Tamoxifen, a type of antiestrogen, blocks the use of estrogen by the tumor cells. Researchers have learned that about 50% of women do not finish the standard 5-year breast cancer treatment with an AI and women who do not complete treatment are at a higher risk of their tumor coming back. Side effects, including hot flashes and pain, are the most common reasons patients list for not completing treatment. Currently, standard treatment for managing side effects involves stopping the AI for a few weeks (a treatment holiday) and using medication and non-medication treatment options specific to the side effects. Switching to a different AI after a treatment holiday may have fewer side effects. Information gathered from this study may help researchers learn whether switching AIs or a guideline-directed intervention is more effective in reducing side effects and improving adherence to AIs in patients with estrogen receptor positive, HER2 negative breast DCIS and stage I-III invasive breast cancer.