Wildomar Radiation Therapy Center

Together: A Better Way To Fight Cancer

We treat cancer by creating an environment of wellness surrounding the patient with exceptional medical professionals, vast clinical expertise, and technical resources. We become part of every community we serve and work with other organizations to bring awareness and education to those affected by cancer.

We have 4 locations in the Inland Empire: Riverside, St. Bernardine Hospital, Wildomar, and Redhawk in Temecula.

Wildomar Radiation Therapy Center is part of The US Oncology Network, which has more than 1,400 affiliated physicians with expertise in medical oncology, hematology, radiation oncology, gynecologic oncology, urology, oncology surgery and other specialties at more than 400 sites of care in 26 states, treating over 1.1 million patients annually. The Network provides strong and comprehensive practice management capabilities and value-based care expertise that are critical for practices navigating today’s challenging healthcare landscape. The Network is supported by McKesson Specialty Health, an industry leader in solutions that empower the community patient care delivery system to advance the science, technology and quality of care.


  • Address

36450 Inland Valley Drive, Suite 101
Wildomar, CA 92595

  • Contact Information

P: (951) 696-0679
F: (951) 696-9748


Tara Washington, MD 

Dr. Tara Washington is a board certified Radiation Oncologist practicing at the Radiation Oncology Centers in Wildomar and Temecula, California. She received her Bachelor of Science Degree from the Massachusetts Institute of Technology and her Medical Degree from the University of Michigan Medical School. She completed her residency training in Radiation Oncology at the Loyola University Medical Center. Subsequently, she joined the Wayne State University School of Medicine Radiation Oncology Department which is now affiliated with the Karmanos Cancer Institute.

Dr. Washington served as a key member of several Multidisciplinary teams including those focused on Breast, Gastrointestinal and Central Nervous System Cancers. She has specialized training and experience in the use of Partial Breast Irradiation and Gamma Knife Radiosurgery. Dr. Washington has also been an invited speaker for multiple professional and community groups as well as local media outlets on topics ranging from Contemporary Issues in the Management of Localized Breast Cancer to Current Recommendations for Cancer Screening.

Medical School: University of Michigan Medical School
Residency: Loyola University Medical Center

Board Certification: The American Board of Radiology


• American Society for Therapeutic Radiology and Oncology (ASTRO)
• American Medical Association

James Mason, MD 

Dr. James Mason is a board certified Radiation Oncologist practicing at the Radiation Oncology Centers at Wildomar and Redhawk. He received both his BS and MD degrees from Wayne State University in Detroit, Michigan. Following this, he completed an internship in internal medicine and a residency in radiation oncology at Wayne State University. Subsequently, he graduated from Harvard University’s School of Public Health with an MPH in 2004. 

Prior to relocating to Southern California, Dr. Mason was a staff physician for 6 years at the Cleveland Clinic Foundation in Cleveland, Ohio. Dr. Mason has published articles on breast and lung cancer. His areas of expertise include HDR brachytherapy, LDR brachytherapy, intensity modulated radiation therapy, prostate brachytherapy, stereotactic radiosurgery, 3D conformal radiation therapy, and Mammosite®.

Masters: Harvard University’s School of Public Health
Medical School: Wayne State University
Residency: Wayne State University

Board Certification: The American Board of Radiology


• American Society for Therapeutic Radiology and Oncology (ASTRO)
• American Medical Association



  • 3D Conformal Radiation Therapy
  • 3D Ultrasound Imaging
  • Calypso® 4D Localization System ("GPS for the Body")
  • CT Scanning & Simulation
  • RapidArc® Radiotherapy
  • Respiratory Gating
  • Stereotactic Body Radiation Therapy (SBRT)
  • Stereotactic Radiosurgery (SRS)





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