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Dr. Wilson Hernandez

Dr. Wilson Hernandez is a Board Certified Radiation Oncologist. He received his radiation therapy training at the University of Minnesota in Minneapolis, MN. He has previous background as Internist which he practiced in San Antonio, TX. Dr. Hernandez has resided with his wife and children in the Dallas Fort Worth area since 2007.

RapidArc, a new modality of treatment for Prostate Cancer

The advances in treatment for Prostate Cancer have minimized the risk of damage to healthy surrounding tissues like the Bladder and Rectum. RapidArc provides an innovative way to provide IMRT to the prostate, improving the dose distribution and minimizing damage to normal tissue. This technology is available at the Prostate Cancer Center.

Frequently Asked Questions

My urologist says my prostate biopsies showed prostate cancer. What do I do now?

Answer: Remain calm. A wide range of good treatment options exist for prostate cancer. Talk to your urologist about which treatments are best for you.

Radiation therapy is an option for treatment of my prostate cancer. How does it work?

Answer: Radiation therapy is a time proven treatment for cancer. Most tumors are more sensitive to radiation and thus can be effectively treated. Radiation can take several forms including radioactive seeds (gamma rays), proton beam, and man made X-ray treatment.

So what is all the excitement about Image Guided IMRT and what is it anyway?

Answer: Image guided radiotherapy represents one of the most significant technical advances in radiotherapy. Image guided radiotherapy shows significant promise in improving our ability to give sufficient radiation doses to sterilize tumors while protecting normal structures and thus potentially decreasing the risk of complications.

You have used the term IMRT. What does it mean?

Answer: Intensity Modulated Radiation Therapy (IMRT) is a relatively recently developed technique to improve the delivery of radiation therapy by the linear accelerator. Instead of maintaining a uniform radiation beam as used in conventional or 3 dimensional radiotherapy, IMRT uses devices within the machine to divide the radiation beam into multiple smaller beams called beamlets that can have different intensities (modulated) within the area being treated. This allows more precise adjustment of radiation doses to the tissues within the target area allowing increased dose to the prostate while relatively sparing the surrounding bladder and rectum. This is important, as several recent medical studies have suggested that higher prostate doses are associated with increased curability.

How do you get set up for IMRT?

Answer: Several steps are required to set up your therapy. Prior to beginning your treatment, you will come to our office for imaging. Generally speaking, a Cat Scan of the pelvis is performed although occasionally additional scans including a MRI are obtained. At the time of the Cat Scan, the staff will position you in the treatment position. A small amount of dye may be introduced into the urethra at this time for patients receiving treatment after surgery. The whole process generally takes about 1 hour. During the next few days, the planning process takes place using the images from the Cat Scan. You do not need to be present at this time. Your IMRT treatment plan is prepared by your physician in conjunction with the medical physics staff.

What happens when my treatment plan is complete?

Answer: When your plan is complete, the staff will arrange for a final “simulation” appointment. You will be brought to the actual treatment room for a final run through to double check your position, measurements, and the feasibility of the computer derived plan. An X-ray or scan may be taken at this time. Generally, everything checks out and treatment can begin.

What do you do with the images obtained before receiving radiation treatment?

Answer: There are two types of images that can be obtained in the treatment room. The first is similar to the initial cat scan used to create the treatment plan. The staff then uses this new image by superimposing it over the original cat scan (aren’t computers great!). Notation can be made of any internal organ movement and the treatment position can be adjusted to accommodate and thus increase the accuracy of the treatment. Increased accuracy over the seven to eight weeks of treatment can be associated with an increased potential for cure with a decrease risk of side effects and complications.

The second form of image guided therapy requires your urologist to place several inert marker seeds in the prostatic area. These seeds are then visualized just prior to therapy in the treatment room and compared to the initial seed position. Adjustment can then be made.

This treatment sounds Interesting. But can I afford it?

Answer: The treatment is a medicare reimbursed therapy and is approved by most private insurance carriers. Coverage is generally good although your individual plan may be subject to co-pay and/or deductible amounts. Feel free to contact our staff if you have any questions and we will do our best to help you.

I think I am interested in image guided radiotherapy. How do I get started?

Answer: The usual first step is to make an appointment for a consultation with our physician to be sure that you are a good candidate for Radiation Treatment. This visit is similar to those in other doctors offices with a review of your medical history and a physical examination. We then review with you the procedure as well as its risks. Usually you receive no radiation exposure at this time although an occasional patient may receive a Cat Scan to begin the planning process.

Image Guided Intensity Modulated Radiation Therapy (IMRT) for Prostate Cancer

How is the IMRT radiation treatment given?

Answer: Your radiation treatments are administrated by a trained therapist in a dedicated room. The treatment is given by a linear accelerator (pictured below) while you lie on a couch. The arrangement is quite “roomy” unlike that of a cat scan or MRI. The actual treatment is painless. When receiving the treatment, you are monitored by closed circuit TV and you may converse with the staff by intercom.

But what about Image Guided Therapy?

Answer: While Intensity Modulated Radiation Therapy (IMRT) is very accurate, it does have a short coming. The entire plan is based upon your initial Cat Scan image which fixes the position of the internal organs. However, the prostate, bladder, rectum and other organs display some movement and there can be a variation in position of the organs relative to the initial Cat Scan of several millimeters to as much as a centimeter or two (1 cm ~ 4/10 inch).

To counter this organ movement, we acquire your image on a frequent basis (often daily). You are placed on the treatment couch in the treatment room in the usual way. However, just prior to beginning your treatment, an image is obtained to determine the relative positions of the internal organs.