Open-label, Phase II Study of Stomatitis Prevention With a Steroid-based Mouthwash in Post-menopausal Women With Estrogen-receptor-positive (ER+), Human Epidermal Growth Factor Receptor 2 (HER2)- Metastatic or Locally Advanced Breast Cancer

Kaiser Permanente - Mid Atlantic Permanete Research Institut Kaiser Permanente Mid-Atlantic, Rockville

Delta Oncology Associates Delta Hematology/Oncology, Portsmouth

M. Francisco Gonzalez, MD.PA Hematology Oncology Center, Columbia

Southeastern Regional Medical Center, Newnan

Karmanos Cancer Institute Karmanos Cancer Institute (2), Detroit

North Shore University Health System NorthShore University, Evanston

Saint Luke's Hospital/Marion Bloch Neuroscience Institute Cancer Institute, Kansas City

Highlands Oncology Group Highlands Oncology Group (22), Fayetteville

Oncology Consultants Oncology Consultants, P.A., Houston

Los Angeles Hematology/Oncology Medical Group, Los Angeles

Kaiser Permanente Medical Group Kaiser Permanente-Moanalua M.C, Anaheim

University of California Irvine UC Irvine Medical Center, Orange

University of California San Francisco UCSF Medical Center, San Francisco

California Pacific Medical Center SC, San Francisco

OnCare Hawaii, ‘Aiea

Northwest Medical Specialties Northwest Medical - Puyallup, Tacoma

University of California at Los Angeles UCLA and TRIO Network, Los Angeles

University of Connecticut Health Center, Farmington

Oncology Specialists, SC Onc Specialists, Park Ridge

University of Maryland School of Medicine University of Maryland, Baltimore

Regional Cancer Care Associates Cancer and Hematologic Disease, Cherry Hill

Hematology Oncology Associates of Northern New Jersey PA DeptofHem-OncofNorthern NJ (2), Morristown

University of Texas/MD Anderson Cancer Center Dept.ofMDAndersonCancerCtr(2), Houston