Advances in Radiation Therapy Ease Treatment
John Powell, MD
American Cancer Society projects a total of 1,660,290 new cancer cases and
580,350 cancer deaths in the United States in 2013. It is encouraging that
overall cancer death rates in the U.S. have declined 20 percent from the peak
in 1991, yet cancer remains one of our greatest public health challenges, as
well as a life-changing diagnosis for patients.
to two-thirds of all cancer patients will receive radiation therapy at some time
during their illness, some for curative treatment, others for palliation (to
make them more comfortable). As a radiation oncologist, my role is to help
patients understand and navigate their complicated disease; to recommend,
design, and oversee the best possible radiation treatment; to manage symptoms
of the disease, as well as side effects; and to monitor treatment results. This
is facilitated through a team approach in the Radiation Oncology Department and
depends on a variety of professionals working together with an ever-changing
array of advanced technology.
have advances in technology improved the patient experience?
in diagnostic imaging, including computerized tomography (CT), magnetic
resonance imaging (MRI), and positron emission tomography (PET), have increased
our ability to accurately understand the extent of a patient’s cancer. As a
result we can treat cancer more precisely than ever before by pinpointing its
in radiation treatment planning, such as three-dimensional conformal (3D)
radiation therapy and intensity-modulated radiation therapy (IMRT),
use detailed imaging and powerful software to optimize radiation dose. This
allows treatment to be individualized for each patient’s situation, providing
the best dose of radiation to the target while minimizing impact on healthy
tissue. For example, IMRT has had a major impact on how external beam radiation
therapy is used to treat prostate cancer. The prostate lies in close proximity
to the bladder and rectum, which are both sensitive areas. We use IMRT to
precisely sculpt the radiation fields to minimize radiation to the bladder and
rectum, while increasing the dose of radiation to the prostate, increasing
effectiveness with the fewest possible side effects.
in the delivery of radiation therapy are also important to reduce the risks
from treatment. A good example of how this works is respiratory gating,
which coordinates patient breathing with radiation delivery. For women with
left-sided breast cancer, respiratory gating can be employed to protect
long-term heart health. Using an infrared camera to monitor respiratory motion,
patients are trained to hold their breath during treatment in a precise way to
minimize the dose of radiation to the heart, reducing cardiac risk while
receiving the best treatment for their breast cancer.
certain situations changes in the radiation dose per treatment, as well as the
total number of treatments, are having a significant impact on radiation therapy.
Traditionally, radiation therapy has been given in a series of treatments, once
a day, in small doses, for several weeks, depending on the situation. An
innovative approach called stereotactic body radiotherapy (SBRT), administers
a high dose per treatment with such precision and focus (usually to small
tumors) that a full course of treatment is possible in one to five sessions.
For patients with early stage lung cancer who cannot undergo surgery, SBRT can
provide better tumor control with fewer side effects than traditional, longer
courses of treatment. This technology continues to evolve and its potential is
being explored for use in a variety of other situations.
is a complex diagnosis. There are different approaches to treatment, which have
varying effects on the overall health of patients. Although medical advances
are the foundation for high quality treatment, compassionate patient-centered
care is also critical for true healing. It takes great strength and bravery to
face cancer, as well as support from family and loved ones, your medical team,
and the cancer-support community. It is an honor to be part of that support
network for patients who are confronting what is often the most serious illness
of their lives.
Powell is board certified in radiation oncology and is medical director of
radiation therapy at Cayuga Medical Center. He serves on the medical staffs of
Roswell Park Cancer Institute and Cayuga Medical Center.