Follow us on Facebook

About Westlake Radiation Oncology Medical Center

Westlake Radiation Oncology Medical Center in Westlake Village, California is part of one of the largest radiation therapy providers for cancer patients in California: Coastal Radiation Oncology Medical Group.

At Westlake Radiation Oncology Medical Center, our mission is to help our patients fight cancer. To accomplish this, we provide the highest standard of care in radiation oncology in an atmosphere of openness, honesty, caring, emotional support and clinical expertise.

Service to our patients comes first.


Westlake Physicians

Dr. Eugene Ahn  

Dr. Eugene Ahn

A graduate of the University of Washington, Dr. Ahn attended medical school at the New York University School of Medicine and did his residency at UCLA Medical Center . He is board certified in therapeutic radiology with a particular interest in stereotactic radiosurgery for brain tumors and head and neck cancers. In addition, he has significant experience in MammoSite Brachytherapy for early stage breast cancer. Dr. Ahn 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. He has published on stereotactic radiosurgery and is the recipient of the Young Oncologist Research Award 2003 from the American Radium Society. Dr. Ahn is based in the Westlake Village/Thousand Oaks centers and is co-medical director of the Los Robles Gamma Knife Center in Thousand Oaks. Dr. Ahn is a member of the American Society for Therapeutic Radiology and Oncology, Los Angeles Radiological Society, American Radium Society, and American Society of Clinical Oncology.

Dr. Robert Hesselgesser  

Dr. Robert Hesselgesser

A graduate of USC and New York Medical College , Dr. Hesselgesser completed his residency in radiation oncology at LA County USC Medical Center. Board-certified in radiation oncology in 1975, he is a member of the American Medical Association, the American Society of Clinical Oncology, the American College of Radiology, the American Society of Therapeutic Radiology and Oncology and the American Endocurietherapy Society. Dr. Hesselgesser is a specialist in radioactive implants with high and low dose rate Iridium-192, and has lectured internationally on the topic, including its use in lung, brain and nasopharyngeal tumors. He has performed over 250 I-125 prostate implants, one of the largest series done by a single physician.

Westlake Treatments

Westlake Radiation Oncology Medical Center provides cancer patients with a some of the most advanced radiation therapy treatments available, including:

  • Intensity Modulated Radiation Therapy (IMRT) – a sophisticated type of external beam radiotherapy which allows delivery of precisely targeted radiation beams to tumors, while sparing the surrounding healthy organs and tissues.

  • Image Guided Radiotherapy (IGRT) – visualized CT scans that verify target locations immediately before treatment delivery. In conjunction with IMRT, this allows for unprecedented accuracy in delivering radiotherapy.

  • Three-Dimensional Conformal Radiation Therapy (3D-CRT) – a sophisticated set of computer assisted tomography scans (CT or CAT scans) and/or magnetic resonance imaging scans (MR or MRI scans) that create detailed, three-dimensional representations of tumors and surrounding organs for precise delivery of radiation beams to the exact size and shape of the tumor.

  • Superficial Radiotherapy (SRT) – a proven skin cancer treatment method for treating basal and squamous cell
    carcinomas since the 1950’s. Because of its non-invasive nature, SRT is a logical choice for primary lesions that otherwise require difficult or extensive surgery of sensitive structures in the head and neck regions such as the fold in the nose, eyelids, lips, corner of mouth, and the lining of the ear, where surgery would result in a poor cosmetic outcome.

North Oaks Location

Westlake Radiation Oncology Medical Center
40 Westlake Blvd.
Westlake Village, California 91361

Phone: (805) 494-4483
Fax: (805) 494-9555


View Larger Map



Request an Appointment


Messages that you send to Westlake Radiation Oncology Medical Center by e-mail may not be secure. If you choose to send any confidential information to us via e-mail, you accept the risk that a third party may intercept and use this information. If this is of an urgent nature concerning your health, please contact your primary care physician, go to the local emergency room, or call 911. While we cannot diagnose or treat via e-mail, we can provide information and help schedule an appointment if necessary.

Westlake Radiation Oncology Medical Center is a member of the Oncure Medical Corp. national network of cancer treatment centers.
Copyright © 2011 Oncure Medical Corp. | Privacy Policy