Physicians
Our radiation oncology experts bring their extensive education and experience to each patient, one at a time. We understand that every patient requires individual attention as each person and disease course is unique.
Our radiation oncologists are highly skilled in both conventional and cutting-edge radiation therapies. At the UC Davis Comprehensive Cancer Center, we seek to provide the most innovative and effective cancer treatments available.
UC Davis faculty radiation oncologists frequently specialize in certain procedures or pursue specific fields of interest. However, the listed specialties of the department faculty and physicians below is only a sampling of their treatment areas. If you do not see a specialty or interest below to match your diagnosis or concern, please call 916-734-1971 or 800-770-9275, Monday through Friday 8 a.m. to 5 p.m. for more information.
Radiation Oncology Faculty
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| Richard Valicenti, M.D. Department Chair of Radiation Oncology Professor Areas of Specialty: prostate or other genitourinary (GU) cancers, prostate cancer brachytherapy, gamma knife |
Allen M. Chen, M.D. Director, Residency and Fellowship Training Program Associate Professor Areas of Specialty: head/neck and lung cancers, stereotactic body radiotherapy (SBRT), breast cancer, sarcoma/melanoma, lymphoma |
Megan Daly, M.D. Assistant Professor Areas of Specialty: head/neck and lung cancers, lymphoma, stereotactic body radiotherapy (SBRT), intensity modulated radiation therapy (IMRT), and image guided radiation therapy (IGRT) |
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| Ruben Fragoso, M.D., Ph.D. Assistant Professor Areas of Specialty: brain tumors, gamma knife, pediatric cancer |
Jyoti Mayadev, M.D. Assistant Professor Areas of Specialty: breast and gynecological (GYN) cancers, breast and gynecological brachytherapy, high dose rate (HDR) brachytherapy |
Arta Monjazeb, M.D., Ph.D. Assistant Professor Areas of Specialty: colon, rectal and anal cancer, stomach and pancreatic cancer |
| Theodore L. Phillips, M.D. Professor Areas of Speciality: brain tumors, sarcoma |








