The co-authors of Invasion of the Prostate Snatchers, blog alternate posts weekly. We invite you to post your comments.

Tuesday, March 19, 2013

Third Dispatch from the Front--IMRT


In my last blog, I said that after all this time living with prostate cancer the uncertainty was beginning to wear on my nerves.  At this point, and having thoroughly researched all my options, the idea of having my prostate fried by electrons doesn’t seem quite so alarming, and as four-letter words go, “cure” has a sweet ring to it.

I’m talking about IMRT, which is short for Intensity Modulated Radiation Therapy. IMRT is a precisely targeted procedure that allows the physician to control the intensity of the radiation beam within a given field. This means that a much higher dose may be given to a tumor within the prostate without an increase in radiation to the surrounding tissue or organs. And if the cancer has spread through the wall of the prostate gland into the seminal vesicles (as in my case) the target field and dosage can be adjusted as necessary.

The big advantage of IMRT over regular external beam radiation is that the beam can be shaped to the exact dimensions of the area to be radiated. And instead of a solid beam of uniform intensity, it utilizes a variety of small independent beams known as “multileaf collimators” that can be turned on or blocked during treatment, varying the radiation beam intensity across the targeted field.

Because of the complexity of the treatment plan, radiation oncologists employ special high-speed computers, treatment-planning software, diagnostic imaging, and positioning devices molded to fit the precise contours of the individual patient. Typically a patient will be required to have several scans, and a team consisting of a radiation oncologist, a medical physicist, a dosimetrist (who sets the radiation dosage), a technician (who does the set-up session), a therapist and a radiation oncology nurse will oversee the treatment.

As with conventional radiation therapy, multiple treatments are required, but with IMRT, the eight-to-nine weeks of treatments (lasting about twenty minutes each) significantly lower the risk of adverse side effects, and the chance of a cure is substantially higher. When I first saw the twelve-foot tall linear accelerator in the treatment room I have to admit I found the idea of having a mountain of energy shot at my pelvis from this giant ray gun--the muzzle of which would be situated barely two inches from my pecker--extremely daunting. And the matter of “rectal burn” cannot be ignored.  However I have been assured that with IMRT rectal irritation is generally temporary, and can be relieved with medication.

So it’s decision time again. I still wish I could safely stay on Active Surveillance, but with IMRT the odds are favorable for a cure, Dr. Bahn has advised me to go for it, as has Dr. Scholz. Even I, the ultimate “Refusenik,” suspect it is time to act.

I’ll keep you posted!

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