The Varian 2100SC linear accelerator uses high-energy X-rays and electrons to treat tumors while sparing healthy tissue. Intensity modulated radiation therapy (IMRT) and image guided radiation therapy (IGRT) allow radiation oncologists to precisely target tumors and account for tumor movement, improving treatment effectiveness and reducing side effects. These advanced techniques are used at InterCommunity Cancer Institute to provide effective radiotherapy with fewer side effects.

1. Treatment Innovation
Varian 2100SC Linear Accelerator
Medical linear accelerators are computerized machines used
for delivering radiotherapy treatments. They produce high-
energy X-rays for treating tumors deep within the body or high-
energy electrons for more superficial lesions. The accelerating
structure is located in a gantry that rotates in a plane around
the patient who lies on an adjustable couch. There may also
be imaging devices for localizing the target just before the
treatment. The accelerators are located in specially constructed
treatment rooms with thick concrete walls that shield staff and
other members of the public from the X-rays that they produce.
When high-energy photons or electrons strike human tissue,
they damage it. However, when the radiation is delivered
correctly, normal tissue can repair itself, but malignant cells
cannot. The advantage of using the high-energy radiation
(millions of electron volts) produced by linear accelerators is
that the maximum dose deposited lies some distance below
the surface of the skin. This skin-sparing effect coupled with the ability to direct many beams from different
angles around the patient allows radiation oncologists to treat a deep-seated tumor to a high dose without
significantly damaging the healthy tissue above it. Using these principles, radiation oncologists and
physicists work collaboratively to create individualized treatment plans for each patient, optimized to kill
the malignant cells while sparing the surrounding normal tissue as much as possible.
Intensity Modulated Radiation Therapy (IMRT)
IMRT uses a sophisticated dose calculation to design
and deliver precisely targeted conformal radiation. This
process involves many uniquely shaped radiation fields
that are delivered to the patient using various angles
and approaches. During each field of treatment, the dose
delivered is contoured by the multi-leaf collimator. The
collimator is a motorized device in the head of the linear
accelerator that consists of a number of moving leaves that
position themselves dynamically to block portions of the
primary beam and create a desired shape that mirrors the
profile of the tumor. Our radiation oncologists and staff
physicist critically evaluate the trade-offs between avoiding normal tissues and adjusting radiation doses to
the tumor. IMRT is useful in treating small, fairly stationary targets surrounded by a large volume of normal
tissue and/or critical structures that are especially close to the targeted tumor.
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ICCI Clermont ICCC Lady Lake ICCC Leesburg
1920 Don Wickham Dr., Suite 130 922 Rolling Acres Rd. 301 S. Lake St.
Clermont, FL 34711 Lady Lake, FL 32159 Leesburg, FL 34748
Phone: 352.243.9709 | www.careyoudeserve.com

2. Treatment Innovation
Varian 2100SC Linear Accelerator
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Image Guided Radiation Therapy (IGRT)
Image-guided radiation therapy is radiation treatment
guided by imaging equipment, such as CT, ultrasound
or stereoscopic X-rays, taken prior to treatment delivery.
IGRT allows radiation to be delivered to tumors with more
precision than was traditionally possible, thus increasing
treatment effectiveness and minimizing side effects. One of
the challenges encountered when radiation is delivered to
a tumor is that the tumor can move based on the patient’s
day-to-day position on the treatment table as well as from
normal organ movement. IGRT allows us to better deliver
the radiation dose directly to the cancer by using a variety
of automated and tracking systems.
At InterCommunity Cancer Institute, our oncologists are confident that we can provide effective external
beam radiotherapy with fewer side effects for your patient. For more information about brachytherapy and
other treatment technologies, or to refer your patient to ICCI, call 352.243.9709.
ICCI Clermont ICCC Lady Lake ICCC Leesburg
1920 Don Wickham Dr., Suite 130 922 Rolling Acres Rd. 301 S. Lake St.
Clermont, FL 34711 Lady Lake, FL 32159 Leesburg, FL 34748
Phone: 352.243.9709 | www.careyoudeserve.com