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Sydney Brehany

Dr. Sydney Brehany, MD



Dr. Sydney Brehany joined Rocky Mountain Cancer Center in 2023. As a medical oncologist and hematologist, she is ready to stand by your side throughout your cancer journey. Although she is comfortable treating a wide variety of cancers and blood disorders, her special focus is on breast cancer and gynecologic cancers, such as ovarian, uterine, and cervical cancers. Dr. Brehany has a unique interest in conditions that might run in families, like hereditary breast and ovarian cancer (HBOC) syndrome and Lynch syndrome. With her expertise in genetic cancer risk assessment, she can identify individuals at risk and guide them on steps to lower that risk for both the patient and their loved ones. She has particular experience with cancer prevention and early detection in patients at high risk for breast cancer. Dr. Brehany regularly participates in multi-disciplinary tumor boards alongside radiologists, pathologists, surgical oncologists, and radiation oncologists. She strongly believes cancer care is a team effort to bring patients the most up-to-date and comprehensive treatment plans possible.
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4715 Arapahoe Ave
Boulder, CO, 80303
  • Accepting New Patients
Mon8:00 am - 5:00 pm
Tue8:00 am - 5:00 pm
Wed8:00 am - 5:00 pm
Thu8:00 am - 5:00 pm
Fri8:00 am - 5:00 pm
  • Accepting New Patients



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