Intensity-Modulated Radiation Therapy for Anal Cancer: Toxicity versus Outcomes

Cancer of the anal canal is an uncommon malignancy, with an estimated 5,290 cases diagnosed in the United States in 2009; however, its incidence has been increasing over the past several decades (www.cancer.gov). Historically, first-line therapy was an abdominoperineal resection (APR), resulting in a permanent colostomy. Long-term cure rates following resection alone have varied in the literature, but results as high as 71% have been reported. For most patients, however, avoidance of radical resection and permanent colostomy placement are highly desirable.[1]

Table 1Nigro and colleagues at Wayne State University pioneered the non-operative treatment paradigm for anal canal cancers.[2,3] Their initial investigation consisted of three patients treated with approximately 30 Gy radiation therapy (RT) with concurrent 5-fluorouracil (5FU) and mitomycin C (MMC). Two patients underwent planned APR with no residual disease demonstrated by pathologic assessment and the third patient declined surgical intervention, with no disease relapse in follow-up. This important preliminary data spawned numerous investigations of non-operative management of anal canal cancer.

source: CancerNetwork

Varian Medical Systems to Showcase Advanced Motion Management Technology for the Treatment of Lung Cancer at CHINA-HOSPEQ 2010

BEIJING, Aug. 17 /PRNewswire-FirstCall/ -- Varian Medical Systems, Inc. (NYSE: VAR) will showcase the company's new Gated RapidArc technology on its Trilogy® machine with advanced motion management capabilities at the 2010 CHINA-HOSPEQ exhibition being held in Beijing August 19-21 by China's Ministry of Health. Varian, the world's leading manufacturer of medical technology for treating cancer and a premier supplier of X-ray imaging technology, will also exhibit its software for planning and for managing radiation therapy treatments.

"Our next generation Gated RapidArc technology, which was introduced five months ago for the Trilogy and other Varian accelerators, enables clinicians to monitor and adjust for tumor motion during a RapidArc® treatment," said Xiaoyun Wang, managing director of Varian's Oncology Systems operations in Beijing. "This sophisticated new tool makes it possible to monitor patient breathing and compensate for tumor motion during lung cancer treatments. This Gated RapidArc approach can 'gate' the beam—turn it on and off—in response to tumor motion during treatment, to target the tumor accurately and spare surrounding healthy tissues.

Varian software on display will include:

* The Eclipse™ treatment planning system, which simplifies modern radiation therapy planning for all kinds of treatment, including 3D conformal, intensity-modulated radiation therapy (IMRT), electron, proton, and brachytherapy treatment. "Eclipse helps doctors and physicists efficiently create and verify treatment plans that have been optimized for each patient," said Wang.
* The ARIA® oncology information system, a comprehensive information and image management system that aggregates patient data into a single, organized, oncology-specific medical chart that simplifies the treatment process so clinicians can focus on caring for patients.

source: Varian Medical Systems

Toward the Future of Radiation Therapy: MD Anderson's Proton Therapy Center Pioneers Pencil Beam Technology for Cancer Patient Care

Treating cancers of the pelvis, brain and in children with new technique designed to 'paint' the tumor

HOUSTON, Aug. 3 /PRNewswire/ -- The radiation oncologist's mantra is to deliver the maximum dose of radiation to the malignant tumor, while limiting damage to healthy surrounding tissue. In proton therapy, this balance is achieved by using proton particles, accelerated to nearly the speed of light, to mimic the shape of a tumor and effectively deposit their energy within the confines of it with sub-millimeter precision.

New tools are enabling physicians at the Proton Therapy Center at The University of Texas MD Anderson Cancer to harness supercharged proton particles and conform them more precisely to the rugged landscape and uneven contours of a tumor. Using a technology known as pencil beam scanning, also known as spot scanning, protons are given the mission: Hone in on cancer cells and destroy. As much an art form as a war tactic, pencil beam proton therapy has the ability to treat the most complex of tumors, like those of the prostate, brain, base of the skull and eye, while leaving healthy tissue and critical structures virtually untouched. The powerful coupling of strength and accuracy offers unmatched capacity to treat a patient's tumor without compromising quality of life during and after treatment.

In nearly a decade since pencil beam's birth in a Swiss physics institute, the world's leading practitioners in radiation science at MD Anderson's Proton Therapy Center have integrated the tested technology into the institution's multidisciplinary approach to patient care and translational cancer research.

source: PR Newswire

ASTRO publishes whole breast irradiation guidelines

Fairfax, Va., August 4, 2010 - The American Society for Radiation Oncology (ASTRO) has released evidence-based guidelines to define appropriate fractionation of whole breast irradiation (WBI), finding that hypofractionated (HF) WBI is effective for many patients with early-stage breast cancer. These guidelines are published in the International Journal of Radiation Oncology•Biology•Physics, the official journal of ASTRO.

Studies have shown that WBI following breast conserving surgery lowers the risk of tumor recurrence and improves survival. Most studies used conventionally fractionated (CF) radiation, which involves daily treatments for up to seven weeks. Despite its effectiveness, conventional fractionation has some drawbacks, including the inconvenience associated with undergoing treatment for a long period of time and the total costs, including both direct health care expenditures and opportunity costs to the patient from being away from home and work.

HF-WBI is a type of WBI that uses a higher dose for each treatment but fewer total treatments, so patients can typically finish radiation in four weeks or less. Several trials have found little difference in the local control and survival outcomes for selected patients treated with either CF-WBI or HF-WBI.

source: ASTRO