Radiation therapy is one of the three primary forms of medical treatment used in the fight against cancer. Radiation therapy can be used both to treat cancer and to reduce symptoms associated with cancer such as pain. It may be used alone or in combination with surgery or chemotherapy. Radiation therapy can be used at almost every place in your body. Radiation therapy is a rapidly evolving field of medicine. New techniques allow for higher delivery of radiation doses to cancer cells while limiting dosage to your normal tissue. Some forms of radiation therapy include: MammositeTM, Stereotactic Body Radiation Therapy (SBRT), VolumetricModualted Arc Therapy (VMAT), Image-Guided Radiation Therapy (IGRT) and Intensity Modulated Radiation Therapy (IMRT), External Beam and 3-D conformal radiation. The length of time for radiation therapy varies according to type of therapy provided and the cancer being treated.
3-D Conformal Radiation
3-D Conformal Radiation Therapy is a high-technology technique that allows radiation beams to be shaped to the contour of the treatment area by using computer simulation. This allows radiation beams to treat the cancerous area and reduces exposure to nearby healthy tissue. This technique is used routinely for most patients undergoing radiation therapy.
External Beam Radiation
One of the most common forms of radiation therapy, external beam radiation treats your cancer from the outside of the body into the cancer through the use of "beams" of radiation. External beam radiation is delivered through a linear accelerator --a high energy x-ray machine. In conjunction with CT scan images and based on extensive planning, the linear accelerator directs radiation beams to the organs and tissues affected by cancer. Typically, external beam radiation treatments last under 15 minutes. External beam radiation is usually delivered 5 days a week for several weeks, depending on cancer type. The procedure itself causes no pain. The most common side effect to external beam radiation is skin irritation.
High-Dose Rate Brachytherapy:
High-Dose Rate (HDR) brachytherapy is form of internal radiotherapy (radiation treatments) At the James E. Cary Cancer Center, high dose radiation is currently used for the treatment of breast cancer with the MammositeTM technique.
Brachytherapy is a quick and powerful way that gives radiation treatments by placing the radiation inside the treatment site. This technique ensures the maximum radiation dose is given where you need it most and minimizing exposure to other areas.
Intensity Modulated Radiation Therapy (IMRT):
Intensity-modulated radiation therapy (IMRT) is an advanced mode of high-precision radiotherapy that uses computer-controlled linear accelerators to deliver precise radiation doses to a malignant tumor or specific areas within the tumor. IMRT allows for the radiation dose to conform more precisely to the three-dimensional (3-D) shape of the tumor by modulating—or controlling—the intensity of the radiation beam in multiple small volumes. IMRT also allows higher radiation doses to be focused to regions within the tumor while minimizing the dose to surrounding normal critical structures. Treatment is carefully planned by using 3-D computed tomography (CT) or magnetic resonance (MRI) images of the patient in conjunction with computerized dose calculations to determine the dose intensity pattern that will best conform to the tumor shape. Typically, combinations of multiple intensity-modulated fields coming from different beam directions produce a custom tailored radiation dose that maximizes tumor dose while also minimizing the dose to adjacent normal tissues.
Because the ratio of normal tissue dose to tumor dose is reduced to a minimum with the IMRT approach, higher and more effective radiation doses can safely be delivered to tumors with fewer side effects compared with conventional radiotherapy techniques. IMRT also has the potential to reduce treatment toxicity, even when doses are not increased. Due to its complexity, IMRT does require slightly longer daily treatment times and additional planning and safety checks before the patient can start the treatment than conventional radiotherapy.
Currently, IMRT is being used most extensively to treat cancers of the prostate), head and neck and central nervous system. IMRT has also been used in limited situations to treat breast, thyroid, lung, as well as in gastrointestinal, gynecologic malignancies and certain types of sarcomas.
Contura Brachytherapy for Breast Cancer:
The James E. Cary Cancer Center, a service of Hannibal Regional Hospital and the Hannibal Clinic is pleased to offer Contura® 5-Day Targeted Radiation Therapy as a breast conserving treatment option for patients with early stage breast cancer. This form of treatment is also known as Accelerated Partial Breast Irradiation and involves surgical placement of a balloon catheter following lumpectomy. Contura® Therapy works by delivering radiation from within the lumpectomy cavity, directly to the tissue surrounding the cavity, where cancer is most likely to recur.
5-Day Targeted Radiation Therapy offers patients with early stage breast cancer the opportunity to complete their radiation treatment in 5 days, as opposed to whole breast treatment which can takes 6 weeks and can cause many logistical problems for patients, such as juggling work schedules and arranging for transportation to and from treatments.
Results from a four year clinical study completed by the American Society of Breast Surgeons indicate that 95% of women treated had good to excellent cosmetic results and that the local recurrence rate of cancer is below 3%. Other surveys indicate that 98% of women who receive Contura®
would recommend that treatment to family and friends and family.
More information can be found at www.mammosite.com
Radioactive iodine is administered in pill form following a thyroidectomy for the purpose of ablating, or destroying, remaining thyroid tissues for patients with common thyroid cancers. This procedure is administered at Hannibal Regional Hospital in the Nuclear Medicine Department under the direction of the Radiation Oncologist of the James E. Cary Cancer Center. Following radioiodine ablation, the patient needs to adhere closely to safety guidelines that will be explained in detail.
Radioactive Iodine may also be used to treat overactive thyroid conditions.
Strontium or Samarium are radioactive medicines used for bone pain from cancer.
Stereotactic Body Radiation Therapy (SBRT):
Sterotactic Body Radiation Therapy (SBRT) is a treatment procedure similar to central nervous system (CNS) stereotactic radiosurgery, except that it deals with tumors outside of the CNS. A stereotactic radiation treatment for the body means that a specially designed coordinate-system is used for the exact localization of the tumors in the body in order to treat it with limited but highly precise treatment fields. SBRT involves the delivery of a single high dose radiation treatment or a few fractionated radiation treatments (usually up to 5 treatments). A high potent biological dose of radiation is delivered to the tumor, improving the cure rates for the tumor, in a manner previously not achievable by standard conventional radiation therapy.
Similarly, because this specialized form of radiation involves the use of multiple radiation beam angles, expert Radiation Oncologists specialized in this technique are able to safely deliver high doses of radiation, with very sharp dose gradient outside the tumor and into the surrounding normal tissue.
With conventional therapy, radiation is delivered in relatively small doses over the course of several weeks, with patients receiving daily treatments during that time. With SBRT, physicians are able to deliver a greater combined dose of radiation over the course of far fewer treatments
Volumetric Modulated Arc Therapy (VMAT):
Volumetric-modulated arc therapy (VMAT) is a type of specialized intensity modulated radiation therapy. VMAT delivers radiation by rotating the radiation machine, through one or more arcs while radiation is continuously delivered.
VMAT allows doctors to treat complex cancers while minimizing exposure to surrounding healthy tissue. VMAT shortens radiation delivery time and offers people with cancer more comfort because it does not require them to lie completely still for long periods of time.