UAB Synopsis, Vol. 24, No. 5, February 14, 2005

Since the UAB Comprehensive Cancer Center occupied the first and third floors of The Kirklin Clinic® (TKC) at Acton Road in 2002, it has featured the most modern radiation equipment, including a Varian Clinac 21EX linear accelerator and a GE HiSpeed NX/iPro computed tomography (cross-sectional imaging) simulator. Now, it is the first facility in Alabama and only the 10th in the United States to offer the complete Tomotherapy HI-ART® (Highly Integrated Adaptive Radiotherapy) system.

Tomotherapy Program Open House February 22 – noon to 2 pm – The Kirklin Clinic® at Acton Road

Tomotherapy is a new way to deliver oncological radiation therapy. A derivative of tomography, the term literally means "slice therapy."

"The Tomotherapy HI-ART System delivers a sophisticated form of intensity-modulated radiotherapy (IMRT) that combines treatment planning, computed tomography (CT) image-guided patient positioning, and treatment delivery into an integrated system," Jennifer De Los Santos, MD, in-house radiation oncologist at TKC at Acton Road, says.

World's most advanced radiation system

"Specifically, the tomotherapy system provides 3-D imaging immediately prior to each treatment to verify the specific location of a patient's tumor. While conventional radiotherapy delivers a wide beam of radiation from several different directions, this system delivers highly targeted radiation beams to the exact tumor site," she explains. "IMRT is especially useful when a tumor wraps around or has a concave relationship with a sensitive normal structure."

The tomotherapy equipment looks like a CT system: the patient lies on a couch that moves continuously through a rotating ring gantry. The gantry houses a linear accelerator that delivers radiation in the shape of a fan beam as the ring turns. With the couch moving at the same time the gantry is rotating, the radiation beam makes a helical pattern around the patient, targeting the tumor with optimal levels of radiation, while minimizing the dose to healthy areas.

"Its capability to both image and treat the tumor without the patient changing position is unique," she says. CT localization allows physicians to accurately treat tumors with closer margins and protect more normal tissue. Because normal tissue receives less radiation, side effects of therapy may be less than with other forms of radiation therapy.

Clinical trials are planned to increase the tumor dose in some cases or decrease the number of times a patient may need treatment. Patients with tumors expected to benefit include those with:

• Prostate cancer. Protocols are under development to decrease overall treatment time.
• Spinal tumors (primary or metastatic). A clinical trial is open for patients to receive 1 to 5 fractions of radiation therapy with tomotherapy instead of several weeks of treatment, which may avoid delays in starting chemotherapy.
• Brain tumors. Many patients with meningiomas or pituitary tumors are not candidates for radiosurgery and require fractionated treatment. Tomotherapy's CT guidance limits the normal tissue exposed to radiation.
• Head and neck cancer. Using targeted IMRT treatments can protect the parotid glands in some patients; UAB has several research studies utilizing IMRT for head and neck cancer.
• Other tumor types, including retreatment of patients who have had prior radiation therapy.