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Current Technologies
3D Conformal Therapy
We offer three-dimensional (3D) conformal treatment planning and
delivery for a wide variety of tumors, for example those located in the prostate, brain,
lung, esophagus and pancreas. "Three dimensional" means the treatment is based on a CT
scan of the region to be treated, so we can use computer software to determine how the
patient will appear from any desired direction. This lets us choose optimal approaches
for the radiation beams. "Conformal" means that the beams are custom shaped to maximize
the treatment of the disease while minimizing the radiation given to healthy tissues.
A sophisticated device (multileaf collimator) is used to block radiation from entering
areas that need protection.
Intensity Modulated Radiation Therapy (IMRT)
IMRT is a new type of therapy which can enable treatment of tumors to
higher dose levels, with risks of side effects that are no higher than with 3D conformal
therapy, and often lower. The concept is that instead of treating with ordinary beams of
radiation, we "paint" the dose where it needs to go, point by point, and skipping over
healthy tissues. By this means, the resulting distributions of radiation dose are able
to have features such as isolated cold pockets, which can act as safe harbors for critical
normal organs like spinal cord or optic nerve. No other method of treatment is able to do
this.
At present, we are able to offer IMRT to selected patients for whom 3D conformal
therapy is likely to have side effects. We most often use it to treat head and neck
tumors. We have also used IMRT to treat disease adjacent to the spinal cord, as well
as to treat prostate cancers.
 
Prostate Seed Implantation
In collaboration with the Department of Urology, we can offer
implants of radioactive seeds to patients with prostate cancer. This outpatient
treatment takes place in a single day, as opposed to 8 weeks for external radiation
(3D conformal therapy). Patients can usually resume most normal activites within a few
days after the procedure. The seeds stay in place permanently, but do not require any
long-term changes in lifestyle. For some patients, this treatment is an attractive
alternative to external radation.
Lung Seed Implantation
We collaborate with BMC's Department of Cardiothoracic Surgery to
offer seed implantation to selected patients as part of their lung tumor surgery. In
this procedure, strings of radioactive seeds are sewn into the cavity left behind after
the tumor is removed. The radiation offers an extra measure of treatment for any cancer
cells which may remain in the margins of the cavity. Like the prostate seeds, these stay
in the patient permanently but cause no long-term disruption to the patient's activities.
Partial Breast Irradiation (PBI)
This is an investigative type of treatment for certain breast patients who have
chosen to have breast-conserving surgery (lumpectomy) follwed by radiation. The traditional
standard of care has been radiation therapy of the entire breast, over a period of 5-6 weeks.
This involves some risk of side effects, as well as a large time commitment for the patient.
However, there are indications that, for some patients, treatment may be equally effective if
3D conformal methods are used, if only part of the breast is treated, and if the treatment time
is kept short.
Boston Medical Center is presently collaborating with Massachusetts General Hospital on a
clinical trial of PBI. Patients who volunteer for the trial, if they are judged eligible
based on the details of their case, are planned with 3D conformal technology. Only the site
of the original tumor is treated and most of the breast is spared. Treatment takes place
twice a day, and is completed in 4 days instead of 30-35. Other trials are in progress at
other centers. PBI is not yet standard care for breast cancer but may become so in the future
if the clinical trials give favorable results.
Stereotactic Radiosurgery (SRS)
This treatment is used for some kinds of small brain tumors. Most SRS
patients have tumors which have spread to the brain from elsewhere in the body. SRS can also
be used against benign brain tumors such as meningioma.
The treatment employs very narrow and tighly controlled beams of radiation to give a very
large dose to the tumor in a single treatment session. One of these treatments is normally
enough to eradicate a small tumor. The patient arrives early in the morning for CT scan, and
is treated in the afternoon, after the customized planning is complete. At the end of the day,
the patient can usually go home. This is often an excellect alternative to a course of 3D
conformal radiation lasting around 6 weeks.
Stereotactic Fractionated Radiation (SRT)
This treatment uses the same technology as SRS but can be used for larger
tumors. It follows a more conventional course of 25-35 short daily treatment sessions, instead
of a single all-day hospital visit.
Digital Portal Imaging
In modern radiation therapy, accurate placement and shaping of the beams is becoming increasingly important. Technologies such as 3D conformal therapy and IMRT depend on precise information about where the beams are being directed. The best way to get this information is with a digital portal imaging system. This device takes a picture of the radiation beam during treatment, showing its exact location on the patient. This picture can be put onto a computer so it can be reviewed by the treatment team.
Recent Technology Additions
Image Guidance
Our new therapy machines are equipped with On-Board Imaging systems, the latest advance in treatment technology. On-Board Imaging enables us to take diagnostic quality x-ray or CT images of the patients, while they are on the treatment couch and in position for therapy. The information can be used to minimize daily errors in patient position, and in some cases to compensate for the normal shifting of organs within the body. Because of our all-new equipment, we are able to offer this technology to the vast majority of our patients on every treatment day. Based on our experience, we believe On-Board Imaging is making a difference in our quality of care by improving the accuracy of daily treatments.
Respiratory Gating
The therapy machines are equipped with gating technology. This allows us to address the tumor motion
which occurs during breathing, for tumors located in the lung or the abdomen. Gating gives us
the ability to, in effect, cancel out the tumor motion, by operating the radiation beam only
when the tumor is in the desired location within the field of view.
High-Dose-Rate (HDR) Brachytherapy
HDR brachytherapy is a type of radioactive implant in which the dose is given during a short treatment session, usually lasting less than one hour. The treatments are given on an outpatient basis. This technique can replace slower methods involving hospital stays of several days duration. We are currently offering HDR treatment to patients with gynecologic cancers.
Stereotactic Radiosurgery
Image Guided Radiosurgery uses the same novel image-guided radation delivery technology to treat small brain and body tumors with
high doses of targeted radiation often in a single session.
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