Cyberknife Clinical Data for Medical Oncologists

As a medical oncologist, a critical part of your role in patient care is directing and overseeing the treatment and management of a patient’s cancer. For this reason, your understanding of the available treatment options is as vital as your knowledge of the various types of cancers.

At CyberKnife of Southern California at Vista, we provide you more opportunities to treat cancer than have previously existed. As a result, we’re helping you provide new hope for patients who traditionally have been challenging to treat or have had few alternatives for successful treatment. With the latest and most powerful CyberKnife® system, we can dramatically reduce the number of radiotherapy sessions... and avoid delaying the start of chemotherapy or disrupting chemotherapy cycles. We also provide an alternative to surgery and conventional radiotherapy. The key is a level of precision far beyond what can be provided by conventional radiation therapy... and the ability to treat tumors virtually anywhere in the body.

CyberKnife tracks a tumor’s true position during treatment and readjusts to ensure the most precise dose conformality available for extracranial radiation. The result is less exposure to normal structures, one to five treatments instead of 30 or more, less impact on patients and the potential to treat medically inoperable patients, previously irradiated patients and radioresistant tumor types.

CLINICAL INDICATIONS for CyberKnife.

With CyberKnife, the range of tumors treatable with stereotactic radiosurgical ablation is unprecedented. Here are the clinical indications for which CyberKnife treatment can benefit your patients and increase the options you’re able to present to them...

• Localized, solid-mass tumors – While conventional radiation therapy doesn’t do as well in the treatment of these kinds of lesions, CyberKnife’s ablative radiation dose is quite effective in destroying or shrinking them. Although CyberKnife is contraindicated for widespread metastatic disease, it is effective in nonsurgical treatment of certain metastatic tumors or tumors that need to be
treated for palliative reasons.

• Metastases to brain, spine & bone – Metastatic tumors in the brain and spine are particularly treatable with CyberKnife, as are osseous metastases. This includes those that are contraindicated for surgical resection and conventional radiotherapy.

• Medically inoperable patients – Because CyberKnife is noninvasive, it can treat patients who can’t endure surgery, have a high risk for postoperative complications or are too sick for chemotherapy. With CyberKnife, treatment takes one to five short sessions, after which patients can immediately return to their lives. All with far less risk, side effects, recovery period, pain, scarring and hospital stay than surgery.

• Unresectable & marginally resectable tumors – Many localized solid-mass tumors that are not resectable may still be treatable – and effectively – by CyberKnife. The same is true for those that are marginally resectable. CyberKnife often is used alone to treat these lesions but can also be combined with other treatments to maximize treatment benefit. CyberKnife can also be used preoperatively to reduce tumor volume to make it more easily resected.

• Tumors adjacent to critical structures – CyberKnife’s submillimeter precision means we’re able to destroy or shrink tumors near to or involved with critical structures. In some cases, critical structures may be the reason a tumor is considered unresectable or only marginally resectable. Tumor proximity to critical structures also increases risk of surgical complication. With significantly less irradiation of surrounding tissues, CyberKnife can even treat tumors untreatable with convention radiotherapy because of nearby critical anatomy.

• Prior radiation treatment – With conventional radiation therapy, previous treatment often precludes future radiotherapy. With CyberKnife, however, highdose, short-course, focused treatment is so precise that cumulative exposure is significantly less. Therefore, previous radiation treatment is not a contraindication for CyberKnife.

• Tumors with high risk of recurrence – For tumor types known to have a high likelihood of recurrence, CyberKnife’s low cumulative exposure makes it an ideal treatment option. If the tumor recurs, the patient can be treated with CyberKnife again (and perhaps multiple times) or be treated with other forms of radiation.

• Radioresistant tumors – It’s true that some tumor types are resistant to the radiobiological effect of conventional radiation therapy. But they aren’t resistant to radiosurgical ablation, which destroys the tumor while preserving surrounding tissue.

• Palliation – While it isn’t indicated for cases of obstructive viscera, CyberKnife can destroy or shrink tumors for reasons of pain relief even if cure is no longer an option.

• Tumors that move – For tumors in the chest and abdomen, respiratory motion complicates radiation treatment. CyberKnife tracks the tumor’s location and movement, and its ablative beam moves in synchrony with the patient’s respiratory pattern and responds to any shifts in the target’s position, maintaining precision throughout treatment.

• Adjunct therapy – With its comparatively low cumulative dose and significantly reduced impact on patients, CyberKnife radiosurgery can be used in combination with other treatments to maximize treatment success.

Brain Tumors:

• Staged stereotactic irradiation for acoustic neuroma. Chang et al. 2005 . Stanford researchers show that fractionated treatment using the CyberKnife System for acoustic neuromas may improve hearing preservation.

• Visual field preservation after multisession CyberKnife radiosurgery for perioptic lesions. Adler, et al. 2006. Stanford University researchers used the CyberKnife System to obtain high rates of tumor control for tumors near (less than 2 mm from) the optic apparatus; over 90% of patients treated maintained or improved their vision.

• Stereotactic radiosurgery using CT cisternography and non-isocentric planning for the treatment of trigeminal neuralgia. Lim et al. 2006. Researchers from Stanford University used the CyberKnife System to treat trigeminal neuralgia.  Ninety percent of patients treated rated their pain control as excellent with limited facial numbness at 10 months follow-up.

• Stereotactic radiosurgery of the postoperative resection cavity for brain metastases. Soltys, et al. 2007. Researchers from Stanford University used the CyberKnife System for adjuvant treatment of brain metastases by targeting post-resection cavities. They obtained a 79% local control rate at 12 months, which compares favorably to historic whole brain radiation treatment results.

• A volumetric study of CyberKnife hypofractionated stereotactic radiotherapy as salvage for progressive malignant brain tumors: initial experience. Giller et al. 2007.  Researchers from Baylor University Medical Center used the CyberKnife System to perform fractionated stereotactic radiosurgery on lesions that are difficult to treat in a single fraction approach.

• Survival following CyberKnife radiosurgery and hypofractionated radiotherapy for newly diagnosed glioblastoma multiforme. Lipani et al. 2008. Researchers from Stanford University performed CyberKnife System treatment on 20 GBM patients after tumor resection. The overall median survival was 16 months, which compares favorably to post-surgical external beam radiation therapy.

Kidney:

• Initial evaluation of Cyberknife technology for extracorporeal renal tissue ablation. Ponsky et al. 2003. Researchers from the Cleveland Clinic Foundation used the CyberKnife System to treat pig kidneys.  They were able to ablate target tissue while leaving nearby tissue undamaged.

Liver: 

• BOOK CHAPTER:  Stereotactic Radiosurgery for Liver Malignancies Using the CyberKnife. Goodman 2008. Researchers from Stanford University treated 20 patients with liver malignancies using the CyberKnife System.  At a median of 7 months they observed limited toxicity and 76% of the treated lesions showed a decrease in size.  The researchers concluded that CyberKnife System treatment to the liver for primary or metastatic malignancies is feasible and safe.

Lung Tumors: 

• Fractionated stereotactic body radiation therapy in the treatment of primary, recurrent, and metastatic lung tumors: the role of positron emission tomography/computed tomography-based treatment planning.  Coon et al. 2008. University of Pittsburgh researchers treated a variety of patients with primary lung cancer, metastatic lung tumors, or recurrent cancer. Using the CyberKnife System they delivered 3 fractions of 20 Gy and concluded it was an effective treatment for patients with medically inoperable recurrent or metastatic lung cancer.

• CyberKnife radiosurgery for stage I lung cancer: results at 36 months. Brown et al. 2007.  Miami researchers show that image-guided robotic stereotactic radiosurgery of lung tumors with the CyberKnife System in medically inoperable patients with early non-small-cell lung cancer (NSCLC) achieves excellent local disease control with limited toxicity to surrounding tissues and, in many cases, might be curative for patients for whom surgery is not an option.

• Radical stereotactic radiosurgery with real-time tumor motion tracking in the treatment of small peripheral lung tumors. Collins et al 2007. Georgetown researchers used the CyberKnife System to deliver 45-60 Gy in 3 fractions to small tumors (including some metastatic tumors) in the outer lung, resulting in 83% local control and 84% overall survival at 12 months.

Pancreas:

• Phase I study of stereotactic radiosurgery in patients with locally advanced pancreatic cancer.  Koong et al. 2004. Stanford University researchers treated patients with locally advanced pancreatic cancer using the CyberKnife System.  They found it was feasible to achieve local control without significant acute gastrointestinal toxicity using a dose of 25 Gy.

• Phase II study to assess the efficacy of conventionally fractionated radiotherapy followed by a stereotactic radiosurgery boost in patients with locally advanced pancreatic cancer. Koong et al. 2005. Stanford University researchers found that concurrent IMRT and 5-FU followed by treatment with the CyberKnife System on patients with locally advanced pancreatic cancer results in excellent local control. Overall survival was not affected, and the combined treatment caused more toxicity than radiosurgery alone.

Prostate: 

• Robotic radiotherapy for prostate cancer with CyberKnife. Hannoun-Levi et al 2007.  This article, in French, concludes that the CyberKnife System is a technical improvement to existing technology (HDR brachytherapy) for delivering a boost after EBRT.

• Stereotactic body radiotherapy for localized prostate cancer: interim results of a prospective phase II clinical trial. King et al. 2008.   Stanford University Researchers used the CyberKnife System to treat 41 low-risk prostate cancer patients.  With a median follow-up of 33 months they found no patient had a PSA failure.  They conclude that the early and late toxicity profile and PSA response for prostate treatment using the CyberKnife System are highly encouraging.

Spine:

• CyberKnife stereotactic radiosurgical treatment of spinal tumors for pain control and quality of life. Degen, et al. 2005. Georgetown University Researchers performed CyberKnife System radiosurgery on patients with both benign and malignant spinal tumors. The results show pain relief and maintenance of quality of life after the treatment.

• CyberKnife radiosurgery for benign intradural extramedullary spinal tumors. Dodd et al. 2006. Stanford University researchers determined that benign lesions located on the spinal cord can be treated safely and effectively with the CyberKnife System.

• Multisession CyberKnife radiosurgery for intramedullary spinal cord arteriovenous malformations. Sinclair et al. 2006. Stanford University researchers used the CyberKnife System to treat spinal cord AVMs with fractionated stereotactic radiosurgery.

• CyberKnife radiosurgery for breast cancer spine metastases: a matched-pair analysis. Gagnon et al. 2007. Georgetown University researchers performed a comparison of external beam radiation therapy to CyberKnife System stereotactic radiosurgery for breast cancer metastasis to the spine.  Outcomes were statistically comparable, even though most of the patients treated with the CyberKnife System had previously undergone external beam radiation therapy.

• Radiosurgery for spinal metastases: clinical experience in 500 cases from a single institution. Gerszten et al. 2007. Researchers from the University of Pittsburgh Medical Center performed the largest published study on spinal radiosurgery. Their results show that single fraction CyberKnife System radiosurgery is safe and effective both as a primary treatment modality and as salvage treatment for spinal tumors.