How Radiation Therapy Works
The photon beam used in radiation treatment is the same kind of beam used
in ordinary chest x-rays or CT scans. However, it has much higher energy
and can cause changes in the nucleus of cells. Both normal tissues and
the tumor tissues will undergo these tiny breaks; however the normal cells
will repair these changes better than tumor cells can. Patients will not
feel the invisible beam passing through them. External Beam Radiation
is a local treatment. It only works where we aim the beam. The radiation
does not circulate through your body and your friends and family are not
exposed to any radiation.
For some cancers, an implant is used to deliver the radiation therapy.
In some gynecologic cancers, a radioactive source is placed within the
vagina or uterus for a short time, to deliver highly localized radiation.
A radioactive source may also be used to focally the cavity left after
lumpectomy to remove a breast cancer.
Adverse effects vary from patient to patient and are determined by the
location of the treatment, the dose required for treatment and the patients’
pre-existing condition. The radiation oncologist, nurse and therapist
will discuss the likely side effects with each patient individually.
Every aspect of the patient’s care is given meticulous attention
to ensure that the patient is treated efficiently and precisely and will
experience the fewest possible side effects. Our physicists, dosimetrists
and radiation therapists conduct daily, weekly and monthly checks on the
department’s equipment to ensure optimum performance. The treatment
team has weekly meetings where every patient’s treatment is reviewed
and discussed in detail.
Targeted Personal Treatment
Radiation oncology at Torrance Memorial gives patients access to the most
progressive cancer imaging, computer-aided planning and targeted treatments
available. The precise delivery of treatment limits the exposure of healthy
tissue to radiation and reduces side effects.
Typically, radiation treatments are applied daily for several minutes and
are not painful. Normal courses of treatment range between 1 day to 7
weeks, depending on the type of cancer, the location in the body and the
goal of the treatment. Radiation treatments can be prescribed as a stand-alone
treatment, but are often in combination with other cancer treatments such
as surgery, chemotherapy/biotherapy or hormonal therapy. While the treatments
usually require no special preparation or fasting, it is recommended you
wear comfortable clothing, as you will need to change in and out of a
hospital gown as part of your treatment.
An initial consultation with a radiation oncologist is the first step in
determining a radiation therapy plan for a patient. Normally two hours
in length, the consult begins with a discussion with a radiation oncology
nurse and completing a health questionnaire. You then meet with a radiation
oncologist for a physical examination and assessment of your medical history.
At that time, the radiation oncologist reviews all imaging and pathology
results to fully understand your specific disease. Should further testing
be required, your appointment is coordinated with your other physicians.
Following these examinations, the radiation oncologist will discuss with
you or a loved one how radiation therapy may fit in to the treatment of
your individual case. This discussion includes the benefits of the therapy,
as well as the potential adverse side effects you may encounter. It is
at this point that the recommendation whether or not to proceed with radiation
therapy is made.
Should you be a candidate for radiation treatments, a return appointment
for a planning session, called "simulation," will typically
be made within a few days of your consult. No radiation treatments are
delivered at the time of consultation or the simulation.
Simulation and Planning
As radiation treatments are personalized to each individual, planning is
necessary to tailor the dosage of radiation, treatment position, and treatment
approach to your specific cancer site. We will also guide you through
how the treatments will work once underway. This appointment - normally
45 minutes to 2 hours in length - works as a "simulation" of
the actual therapy you will receive and insures the proper application
of radiation to maximize its benefits and minimize side effects.
The first step of the planning appointment is to place you on a special
treatment couch. If necessary an immobilizing device may be used to help
you stay still, but as comfortable as possible during your treatments.
A series of images will be taken. These may include CT, MRI or PET scans
to pinpoint the location of your cancer. We use these computerized images
to create a targeted radiation plan.
During this targeting planning, you may be asked to receive one or more
tiny tattoos - less than the size of a pinhead. These permanent blue ink
marks serve two very important purposes: they help assure accurate application
of radiation for each visit during your treatment plan and create a fixed
physical record of which area of your body received radiation. Should
you require additional radiation therapy in the future, this can be very
helpful information for your physicians.
Torrance Memorial offers many state-of-the-art options in radiation technology
combined with sophisticated planning and imaging equipment. These powerful
and precise tools help physicians develop an individualized treatment
plan. Each has a specific function to pinpoint the location of cancerous
cells for treatment and provide the optimum dosage.
Specific treatments include:
Intensity Modulated Radiation Therapy (IMRT) - A highly advanced technique, IMRT delivers high doses of radiation to
tumors while substantially reducing the risk to normal tissue. IMRT is
a complex form of three-dimensional conformal radiation therapy and one
of the most precise and sophisticated treatment techniques currently available.
This relatively new technology is used effectively to treat many kinds
of cancer, especially prostate cancer and cancers of the head and neck.
3-D Conformal Radiation Therapy - 3-D conformal radiation therapy uses CT based treatment planning with
three-dimensional rendering of the tumor and surrounding structures. This
allows for very precise delivery of radiation doses and better avoidance
of normal tissues.
Conventional External Beam Radiation Therapy - This radiation therapy technique uses a linear accelerator to deliver
radiation treatments to somewhat larger treatment areas. CT based treatment
planning is always used and every effort is made to exclude as much of
the normal tissues from the treatment area as possible.
Partial Breast Brachytherapy - "Brachy" comes from the Greek word for "up close."
This new method of internal partial breast radiation delivers radiation
to the tissue surrounding the lumpectomy site and avoids radiation exposure
to breast tissue not adjacent to the cancer. A precise dose of radiation
therapy is delivered through a small tube to a highly localized portion
of the breast over a one-week period, then the tube is removed. Patients
who are candidates for post-lumpectomy brachytherapy are carefully chosen
based on tumor characteristics.
Torrance Memorial also offers a computer-assisted merge of images from
your CT, MRI and PET scans. Combining or "fusing" these images
into a single master image gives physicians and therapists a better understanding
of your tumor and its relationship to the surrounding tissue. This combination
allows for even more precise treatment with less damage to healthy cells.
Start of Treatment
You can expect to receive your first radiation treatment about one week
after your planning session. Treatments are typically given five days
per week, Monday through Friday, except legal holidays. The radiation
therapists will coordinate a treatment time that is convenient for you.
You will meet with a nurse before the start of treatment to discuss management
of side effects that you might experience and education re: what to do
to prepare for treatment. Each week during treatment you will meet with
the radiation oncologist to assess how well you are tolerating the treatments,
keep track of side effects, discuss ways to manage side effects and review
your overall level of health.
The radiation therapists, in collaboration with the nurse, will provide
on-going skin and side effect assessment and education throughout your
course of treatment.
About three weeks following the completion of your radiation therapy treatment,
you will meet with your radiation oncologist to discuss the initial impact
of your treatment, and to help you manage any adverse effects of treatment.
Other follow-up appointments will then be scheduled so that we can track
your recovery and measure your response to treatment. All follow-up appointments
are coordinated with your other oncology physicians.
Safety and Quality
Every aspect of your treatment planning and delivery is given meticulous attention