Frequently Asked Questions

X-rays are a form of electromagnetic radiation (waves of electrical and magnetic energy). Other forms of electromagnetic radiation include radio waves, microwaves, and visible light. X-rays may be of low-energy, such as those used to visualize bones, or of high-energy, such as those used to treat cancer.

High-energy x-rays damage the DNA of both normal and cancerous cells. In response, both types of cells attempt to repair the damage. In the majority of cases, our normal cells are able to do so whereas the cancerous cells typically cannot. This persistent DNA damage within cancerous cells prevents it from continuing to divide or grow. As a result, these cells undergo various forms of cell death.

Radiation is generated in and delivered by a Linear Accelerator (LINAC). These are multi-million dollar machines that are found in almost every radiation department. The LINAC creates the x-rays which enter the patient from the outside in (termed external beam radiation therapy). These x-rays are neither able to be felt or seen by the patient. Radiation is typically delivered from multiple angles (i.e., seven for prostate cancer). The radiation at each angle takes approximately 1-2 minutes to deliver. The entire treatment process, including patient set-up, quality assurance, and radiation delivery, can take up to 15 minutes per day. These treatments are given daily, Monday through Friday, for approximately 8 weeks, depending on the type of cancer being treated.

IMRT (Intensity-Modulated Radiation Therapy) is an evolution of 3D conformal radiation therapy (3D CRT) whereby the target organ (i.e., prostate) is treated, not as a whole organ, but as parts, each receiving varying intensities of radiation from various angles, all determined by a computer. With this technique, the radiation dose conforms very precisely to the shape of the target organ while minimizing the dose to surrounding normal tissue.

Imaged Guided Radiation Therapy (IGRT) is a relatively new way of ensuring that the target organ (i.e., prostate), and not just the patient, are in the correct position. Many studies have shown that despite the fact that the patient is lying in the proper position, the organ being targeted may not be. In fact, the prostate, for example, can move up to 1-2 cm in various directions depending on, among other things, how full the rectum or bladder is. If left unaccounted for, the prostate in this improper position will not receive the full dose of radiation as intended. Even worse, the bladder or rectum, now residing where the prostate should, receives the radiation, potentially increasing the risk of short- and long-term side effects. With Calypso®, not only can we verify the position of the prostate before the radiation is turned on, we can monitor its position during the treatment, ensuring that during the 10-15 minutes, the prostate does not move or drift out of position.

As every patient is different, the approach to that patient is equally unique. It is important, therefore, to meet with a Radiation Oncologist, who will determine the radiation option(s) best suited for you.