Hoag Radiation Oncology:
An important ally in the fight against cancer

Hoag’s Radiation Oncology department encompasses the entire first floor of Hoag Cancer Center, where its dedicated team of medical experts utilizes the latest in state-of-the-art technologies to treat more than 100 patients each day.

The Radiation Oncology Team consists of radiation oncologists, medical physicists, medial dosimetrists, radiation oncology nurses, radiation therapists and support staff, each dedicated to providing excellence in patient-centered care.

Hoag Radiation Oncology offers a wide variety of innovative treatment options using state-of-the-art equipment. The breadth of treatment options offered allows the Radiation Oncologist to select the specific treatment type, which is best suited to each patient’s particular medical needs.

Fish Tank

Innovative Treatment Options:

3D Conformal Radiation Therapy (3DCRT)
Image-Guided Intensity-Modulated Radiation Therapy (IG-IMRT)
Tomotherapy®
Stereotactic Radiation Therapy (SRT) / Stereotactic Body Radiation Therapy (SBRT)
Stereotactic Radiosurgery (SRS)
Gamma Knife Perfexion™
Superficial Radiation Therapy
Prostate Brachytherapy
High Dose Rate Brachytherapy - (HDR)
Mammosite Brachytherapy - Accelerated Partial Breast Treatment (APBT)

Please select any of the above treatment options to find out more about Hoag Radiation Oncology services, or call us at 949/764-5528.

3D Conformal Radiation Therapy (3DCRT)

In the past, radiation oncologists could only plan using two dimensions (width and length), due to the limitations in imaging technology. With current advanced imaging and computer technology, radiation oncologists can plan treatment in three dimensions (width, height and depth). This process is known as 3D Conformal Radiation Therapy (3DCRT).

The process starts with a CT scan which gives a three dimensional picture of the patient’s body, including the tumor to be treated as well as all normal anatomy. This picture may be supplemented with additional information from other 3D images such as PET or MRI scans. Using this picture as a map of the body, the radiation oncologist identifies a target to be treated and any sensitive healthy tissue that needs to be avoided. The radiation oncology team then uses powerful computers to design a radiation plan with multiple beams aimed at the target. Each beam is shaped to deliver the maximum dose possible to the target, while avoiding surrounding sensitive structures. Thus, the radiation “conforms” to the target volume.

3DCRT can be very useful when a tumor is close to a sensitive normal structure. (For example, a lung cancer close to the spinal cord.) The added precision of 3DCRT allows the radiation oncologist to give more dose to the tumor while limiting exposure of normal tissue to safe levels.

For more information about 3DCRT, please call us at 949/764-5528.

Image-Guided Intensity-Modulated Radiation Therapy (IG-IMRT)

Intensity-Modulated Radiation Therapy (IMRT) uses intricately shaped beams to enhance the techniques used in 3D Conformal Radiation Therapy (3DCRT). In 3DCRT, intensity of the radiation is uniform throughout the shape of the beam. With IMRT, the radiation intensity is non-uniform throughout the beam shape. This non-unifrom intensity allows for better control in shaping the radiation delivered to the target volume, while avoiding healthy tissue. (For example, when treating a head and neck cancer while trying to avoid nearby salivary gland and spinal cord.) The complex shaping of radiation using IMRT adds to the capabilities of 3DCRT, and allows the radiation oncologist to give more dose to the tumor while limiting exposure of normal tissue to safe levels.

IMRT can be further enhanced with the use of image-guidance (IG-IMRT). One problem that a radiation oncologist faces is how to position the patients properly for their daily treatments. Tumors aren’t always where they are expected because of movement with breathing, expansion of the gastrointenstinal tract with air or other similar factors. In IG-IMRT, an image is taken daily prior to the radiation treatment, and changes in set up are made to ensure that the tumor is targeted appropriately. (For example, to help visualize the target, the radiation oncologist may implant metal markers in the prostate gland.)

Our Varian 21EX uses a digital imager to visualize metal markers in a 2D fashion on a daily basis. Alternatively, some machines, such as Tomotherapy, can take a 3D image that shows the tumor and the surrounding anatomy directly in order to achieve the appropriate set up. Such image-guided techniques make treatment more accurate, ensuring that radiation is directed at the appropriate target and away from the adjacent healthy tissue.

For more information about IG-IMRT, please call us at 949/764-5528.

Tomotherapy®

Tomotherapy is a specialized treatment machine specifically designed for Image-Guided Intensity-Modulated Radiation Therapy (IG-IMRT). The concept of treating cancer with radiation is a simple one: irradiate the cancer cells and they die. The challenge, therefore, lies in sparing the healthy tissue surrounding the tumor - that’s precisely what Tomotherapy is all about.

Tomotherapy achieves the ability to delivery maximum radiation dose to a target volume while sparing the surrounding healthy tissue by utilizing a CT scanner for daily image guidance to ensure proper patient set-up based on the internal anatomy. The machines superior ability to modulate the intensity of the radiation to conform around the target volume also significantly decreases the dose to healthy tissue.

“The breakthrough technology that makes Tomotherapy unique is that it combines the capabilities of a standard CT scanner with those of a radiation therapy linear accelerator,” explains Radiation Oncologist Peter Chen, M.D. “Like a standard CT scanner, the Tomotherapy source spirals around the patient like a corkscrew, enabling it to take three-dimensional pictures that help doctors to precisely localize treatments. However, instead of the imaging x-rays from a standard CT scanner, the Tomotherapy source, like a linear accelerator, emits cancer-killing megavoltage photons. With both these capabilities in hand, doctors are able to treat patients with unprecedented accuracy.”

Traditionally, radiation therapy treated a tumor by focusing relatively large beams of radiation from two to six directions. In contrast, Tomotherapy uses hundreds of pencil beams of radiation, rotating in a spiral around the tumor and hitting it from all directions. As the beam is rotating, the intensity of the radiation is varied, allowing the radiation oncologist to deliver the radiation with incredible precision. In addition, the radiation can be sculpted to fit the shape of the patient’s tumor, again providing more precise and effective treatment.

Another radiation treatment challenge lies in the movement of tumors - sometimes as little as a millimeter. The Tomotherapy system can provide 3D CT imaging immediately prior to treatment to verify the location of the patient’s tumor. By confirming the precise tumor location, the accuracy of the delivery is greatly increased.

Tomotherapy uses 3D Conformal Radiation Therapy (3DCRT) and IMRT technologies, with the addition of helical delivery and 3D imaging (IG-IMRT) for treatment verification.

For details about Tomotherapy, please visit the Tomotherapy Website, or call us at 949/764-5528.

Stereotactic Radiation Therapy (SRT) / Stereotactic Body Radiation Therapy (SBRT)

Stereotactic Radiation Therapy (SRT) is an intermediate technique, with many of the characteristics of both Stereotactic Radiosurgery (SRS) and Image-Guided Intensity-Modulated Radiation Therapy (IG-IMRT). When applied outside of the brain, this technique is often called Stereotactic Body Radiation Therapy (SBRT). SRT uses doses higher than standard doses with conventional radiation therapy, but lower that SRS. The length of treatment is also intermediate – typically given in five daily dose fractions.

At Hoag, SRT and SBRT are delivered with the Tomotherapy unit. Tomotherapy is especially suited for SRT/SBRT because of the precise nature of helical IMRT, and the capability to take 3D images for treatment verification.

When delivered to the brain, SRT uses a thermoplastic immobilization mask that is molded to the patient’s head. In contrast to the rigid head frame of SRS, this mask is applied non-invasively. When delivered to the body (SBRT), the patient is placed in a molded cradle, and wrapped with plastic covering. Suction is applied to hold the patient in a stable position. In both circumstances, 3D imaging is performed prior to each treatment to verify correct positioning.

SRT is used to treat benign and malignant tumors of the brain, such as meningiomas, pituitary adenomas, acoustic neuromas, large metastases (spread of cancer from other sites in the body), optic tumors, and gliomas (anaplastic astrocytoma, glioblastoma multiforme). SBRT is used to treat selected tumors in the body, such as spinal lesions, liver metastases and lung metastases.

The Hoag Advantage:
Hoag has a distinct advantage with active SRT/SBRT and SRS programs in the same facility. Our weekly multidisciplinary Neuro-Oncology Tumor Board specialists are therefore able to recommend and carry out optimal treatment regimens within this fully integrated facility assuring the patients the best possible treatment options.

For more information about SRT and SBRT, please call us at 949/764-5528.

Stereotactic Radiosurgery (SRS)

Stereotactic Radiosurgery (SRS) is a technique that delivers a single large dose of radiation to a precisely determined target. It is an alternative or adjunct to neurosurgery or conventional radiation.

The term stereotactic refers to a localizing system that uses a rigid head frame attached to the patient’s skull for precision set-up. Radiosurgery refers to the highly focused beams of radiation that can be used for the same purposes as conventional surgery, but without ever cutting or opening up the patient. The only invasive portion of the procedure is attaching the head frame to the skull, which requires only local numbing medications and light sedation for comfort. There is virtually no recovery time, and the patients go home in the afternoon of their treatment day. In addition, the highly focused beams deliver a larger single dose than possible with other radiation techniques. This large single dose has been found to be more effective in treating certain tumors and conditions.

SRS is most commonly used to treat benign and malignant tumors of the brain, such as brain metastases (cancer that has spread from other parts of the body), meningiomas, pituitary adenomas, acoustic schwannomas, arteriovenous malformations (AVMs), and malignant gliomas (anaplastic astrocytomas and glioblastoma multiforme). SRS is also used to treat some neurologic conditions such as trigeminal neuroalgia, epilepsy, and Parkinson’s Disease.

At Hoag, SRS is performed with the Gamma Knife Perfexion, a highly advanced and specialized radiation machine. SRS performed on the Gamma Knife is also referred to as Gamma Knife Radiosurgery (GKRS).

For more information, please visit the Websites for Hoag Gamma Knife Center and Dr. Christopher Duma, or call Hoag Radiation Oncology at 949/764-5528.

Gamma Knife Perfexion™

Hoag is proud to present Gamma Knife Perfexion, the most advanced and specialized radiation machine for Stereotactic Radiosurgery (SRS). Hoag is the first in Southern California to install the premier unit and continues to be the only facility offering Gamma Knife Radiosurgery (GKRS).

Gamma Knife is the most well studied and published technique for delivering SRS and Perfexion is a revolutionary improvement on the existing technology. As compared to previous Gamma Knife units, the Gamma Knife Perfexion has a cylindrical collimator system that increases the ability to treat lesions independent of their location in the brain. The system also greatly improves patient comfort.

Additionally, the Gamma Knife Perfexion has been configured for maximal shielding outside of the treatment region, which greatly reduces unwanted exposure to the patient. And, the unique collimator system allows for custom configurations, greatly expanding the ability to shape radiation dose to conform to the target volume increasing the capability of sparing larger areas of normal, healthy tissue.

The many technological advances of the Gamma Knife Perfexion translate into a safer, more accurate, and more comfortable treatment.

For more information about Gamma Knife technology, please the following Websites: Hoag Gamma Knife Center, Dr. Christopher Duma or Elekta.

Superficial Radiation Therapy (Skin Treatment)

Radiation therapy is an extremely effective method of treating (non-melanoma) skin cancer. Non-melanoma skin cancer includes cell type diagnosis of basal cell and squamous cell.

Superficial (on the skin) treatment for skin cancer (non-melanoma) requires the use of a special machine that will treat the skin but not the underlying tissues. Hoag houses just such a machine. Radiation treatment to skin cancer allows the patient to avoid the alternative option of surgery, which often results in scarring.

Although not much information is shared about this effective treatment option, Hoag’s experienced radiation oncology team performs more than 1,100 treatments each year.

Prostate Brachytherapy

With this technique, radiation can be delivered to the prostate alone by implanting radioactive seeds (permanent seed implants using Iodine-125 or Palladium-103) or by placing needles temporarily into and around the prostate and inserting radioactive Iridium-192 into the needles under computer control (temporary or High Dose Rate Brachytherapy (HDR)).

Both procedures are performed at Hoag. The permanent implant is performed as an outpatient procedure, while the temporary implant requires a two-day hospital admission.

The physicians at Hoag began the implant program in August 1997 and have since performed over 500 such implants, making it one of the busiest prostate implant programs in Orange County. The Hoag physicians who perform this innovative technique trained with Dr. Peter Grimm of the Seattle Prostate Institute. And Hoag physicians continue to practice using the techniques and guidelines established by this pioneering group in Seattle.

The recommended type of implant depends on a number of factors such as the stage of the tumor, size of the prostate, urinary symptoms before the procedure, whether there has been prior prostate surgery and the appearance of the tumor upon biopsy. Brachytherapy is also sometimes combined with a shortened course of external beam radiation therapy (approx. 5 weeks). In all cases of temporary implantation, five weeks of external beam radiation is delivered in addition to the implant.

Temporary side effects of implants can include: mild discomfort, small amounts of blood in the urine for several days, and an increase in urinary symptoms such as frequency, burning, and urgency. As these urinary symptoms increase, a certain percentage of patients will experience temporary urinary obstruction which is treated with catheterization. These may peak one to eight weeks following the implant and will gradually improve over a few months. Long term complications can include: impotence, intermittent rectal bleeding and, occasionally, more persistent urinary symptoms.

The major advantages of implants are the ability to give higher radiation doses than can be attained with external beam radiation (including conformal techniques), and confining the treatment more tightly to the prostate, which should lead to better tumor control and fewer long term complications.

At Hoag, we appear to be achieving the same excellent results seen in Seattle, where the procedures have been refined over the past fifteen years.

For more information, visit the Seattle Prostate Institute’s Website, or call us at 949/764-5528.

High Dose Rate Brachytherapy - (HDR)

High Dose Rate Brachytherapy (HDR), also referred to as “internal radiation therapy.” is a radiation treatment allowing a small radioactive source to be temporarily placed inside numerous types of tumors.

Under computer control the position and timing of source placement can be precisely controlled, allowing the physician to shape the radiation dose to the target. Because of the high dose rate characteristics, brachytherapy treatments can often be delivered on an outpatient basis or with a minimal hospital stay.

HDR is used in the treatment of early breast cancer, gynecological (GYN) cancers and less often in other areas of the body. The treatment may be the only radiation given or may be in conjunction with “external radiation therapy”.

For more information about HDR, please call us at 949/764-5528.

Mammosite Brachytherapy - Accelerated Partial Breast Treatment (APBT)

Mammosite® Brachytherapy is a treatment option offered to selected early stage breast cancer patients in conjunction with a lumpectomy. This treatment option uses a Iridium-192 radioactive source, which delivers radiation to the lumpectomy cavity. At the time of the lumpectomy or shortly after, the surgeon will place a catheter into the cavity which is used as the vehicle for the radioactive source. This treatment is delivered two times per day for five days.

For more information about Mammosite Brachytherapy, please click here, or call us at 949/764-5528.