Dr. Edward Soffen
Source: www.livescience.com
Dr. Edward Soffen is a board-certified radiation oncologist and medical director of the Radiation Oncology Department at CentraState Medical Center's Statesir Cancer Center in Freehold, New Jersey. He contributed this article to Live Science's Expert Voices: Op-Ed & Insights.
As a radiation oncologist, my goal is to use radiation as an extremely powerful and potent tool to eradicate cancer tumors in the body: These techniques save and extend patients' lives every day.
Historically, radiation treatments have been challenged by the damage they cause healthy tissue surrounding a tumor, but new technologies are now slashing those risks.
How radiation therapies work
High-energy radiation kills cancer cells by damaging DNA so severely that the diseased cells die. Radiation treatments may come from a machine (x-ray or proton beam), radioactive material placed in the body near tumor cells, or from a fluid injected into the bloodstream. A patient may receive radiation therapy before or after surgery and/or chemotherapy, depending on the type, location and stage of the cancer.
Today's treatment options target radiation more directly to a tumor — quickly, and less invasively — shortening overall radiation treatment times. And using new Internet-enabled tools, physicians across the country can collaborate by sharing millions of calculations and detailed algorithms for customizing the best treatment protocols for each patient. With just a few computer key strokes, complicated treatment plans can be anonymously shared with other physicians at remote sites who have expertise in a particular oncologic area. Through this collaboration, doctors offer their input and suggestions for optimizing treatment. In turn, the patient benefits from a wide community of physicians who share expertise based upon their research, clinical expertise and first-hand experience.
The result is safer, more effective treatments. Here are five of the most exciting examples:
1. Turning breast cancer upside down
When the breast is treated while the patient is lying face down, with radiation away from the heart and lungs, a recent study found an 86 percent reduction in the amount of lung tissue irradiated in the right breast and a 91 percent reduction in the left breast. Additionally, administering prone-position radiation therapy in this fashion does not inhibit the effectiveness of the treatment in any way.
2. Spacer gel for prostate cancer
Prostate cancer treatment involves delivering a dose of radiation to the prostate that will destroy the tumor cells, but not adversely affect the patient. A new hydrogel, a semi-solid natural substance, will soon be used to decrease toxicity from radiation beams to the nearby rectum. The absorbable gel is injected by a syringe between the prostate and the rectum which pushes the rectum out of the way while treating the prostate. As a result, there is much less radiation inadvertently administered to the rectum through collateral damage. This can significantly improve a patient's daily quality of life — bowel function is much less likely to be affected by scar tissue or ulceration. [Facts About Prostate Cancer (Infographic )]
3. Continual imaging improves precision
Image-Guided Radiation Therapy (IGRT) uses specialized computer software to take continual images of a tumor before and during radiation treatment, which improves the precision and accuracy of the therapy. A tumor can move day by day or shrink during treatment. Tracking a tumor's position in the body each day allows for more accurate targeting and a narrower margin of error when focusing the beam. It is particularly beneficial in the treatment of tumors that are likely to move during treatment, such as those in the lung, and for breast, gastrointestinal, head and neck and prostate cancer.
In fact, the prostate can move a few millimeters each day depending on the amount of fluid in the bladder and stool or gas in the rectum. Head and neck cancers can shrink significantly during treatment, allowing for the possibility of adaptive planning (changing the beams during treatment), again to minimize long term toxicity and side effects.
4. Lung, liver and spine cancers can now require fewer treatments
Stereotactic Body Radiation Therapy (SBRT) offers a newer approach to difficult-to-treat cancers located in the lung, liver and spine. It is a concentrated, high-dose form of radiation that can be delivered very quickly with fewer sessions. Conventional treatment requires 30 radiation treatments daily for about six weeks, compared to SBRT which requires about three to five treatments over the course of only one week. The cancer is treated from a 3D perspective in multiple angles and planes, rather than a few points of contact, so the tumor receives a large dose of radiation, but normal tissue receives much less. By attacking the tumor from many different angles, the dose delivered to the normal tissue (in the path of any one beam) is quite minimal, but when added together from a multitude of beams coming from many different planes, all intersecting inside the tumor, the cancer can be annihilated.
5. Better access to hard-to-reach tumors
Proton-beam therapy is a type of radiation treatment that uses protons rather than x-rays to treat cancer. Protons, however, can target the tumor with lower radiation doses to surrounding normal tissues, depending on the location of the tumor. It has been especially effective for replacing surgery in difficult-to-reach areas, treating tumors that don't respond to chemotherapy, or situations where photon-beam therapy will cause too much collateral damage to surrounding tissue. Simply put, the proton (unlike an x-ray) can stop right in the tumor target and give off all its energy without continuing through the rest of the body. One of the more common uses is to treat prostate cancer. Proton therapy is also a good choice for small tumors in areas which are difficult to pinpoint — like the base of the brain — without affecting critical nerves like those for vision or hearing. Perhaps the most exciting application for this treatment approach is with children. Since children are growing and their tissues are rapidly dividing, proton beam radiation has great potential to limit toxicity for those patients. Children who receive protons will be able to maintain more normal neurocognitive function, preserve lung function, cardiac function and fertility.
While cancer will strike more than 1.6 million Americans in 2015, treatments like these are boosting survival rates. In January 2014, there were nearly 14.5 million American cancer survivors. By January 2024, that number is expected to increase to nearly 19 million.
But make no mistake — radiation therapy, one of the most powerful resources used to defeat cancer, is not done yet. As we speak, treatment developments in molecular biology, imaging technology and newer delivery techniques are in the works, and will continue to provide cancer patients with even less invasive treatment down the road.
Source: www.livescience.com