Eugene S. Ahn, MD

Radiation Oncology


Dr. Ahn is board certified in therapeutic radiology with a particular interest in stereotactic radiosurgery for brain tumors and head and neck cancers. He has significant experience in MammoSite brachytherapy for early stage breast cancer, and he initiated the first MammoSite treatment in Ventura County in 2004. The breast brachytherapy program in Thousand Oaks is now the largest in Ventura, Santa Barbara, and San Luis Obispo counties. Dr. Ahn has published on stereotactic radiosurgery and was the recipient of the Young Oncologist Research Award 2003 from the American Radium Society. He is Vice President of Coastal Radiation Oncology Medical Group, the medical director of Coastal’s Simi Valley Radiation Oncology Center, and is co-medical director of the Los Robles Gamma Knife Center in Thousand Oaks.


Simi Valley Radiation Oncology Center
2985 North Sycamore Dr.
Simi Valley, 93065 California
805-584-0530 Fax
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North Oaks Radiation Oncology Center
2230 Lynn Rd., Suite 103
Thousand Oaks, 91360 California
805-496-2861 Fax
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Westlake Radiation Oncology Center
1240 Westlake Blvd., Suite 103
Westlake Village, 91361 California
805-494-9555 Fax
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University of Washington
Bachelor of Arts, Political Science
New York University Graduate School of Arts and Sciences
Master of Arts, Philosophy with concentration in Medical Ethics and Health Policy
New York
New York University School of Medicine
Doctor of Medicine
New York
New York University Downtown Hospital
PGY-1 in Internal Medicine
New York
UCLA Medical Center
Radiation Oncology
Los Angeles

Awards and Honors

Cum Laude Graduate, Phi Beta Kappa, Elie Wiesel Award for best essay in Ethics

Current and Past Positions

Current Position

Coastal Radiation Oncology - Radiation Oncologist
Ventura, California