Friday, October 09, 2015

On a Serious Note

I have just undergone treatment for prostate cancer.

After reviewing the options - surgical or radiation treatment - I found a fairly new treatment called Cyberknife (a brand name for robotic Stereotactic Body Radiation Therapy, or SBRT).

The treatment replaces ten weeks of radiation therapy with five days!   It's much less expensive, and the total radiation exposure over the full course of treatment is about half the exposure from conventional therapy.  Yet the clinical results are essentially the same as conventional radiation treatment.

They are able to do this by using a precisely focussed beam of radiation, which allows them to administer a much higher dosage to the tumor with little damage to surrounding tissues.

Before the week of treatment, they implanted 4 gold seeds in my prostate, and then, using MRI and CT scans, created a computer model of my prostate and the cancer.

During the radiation treatment (which lasted about 45 minutes each day), the computer used real-time CT scans to precisely position the beam of radiation on the places they wanted.  I simply had to lie reasonably still on the bed.  

Click the link to see a Cyberknife promotional video.
A sequence showing the robot arm in action starts at 1:08.
The bed itself was mounted on a robotic arm so they could position it in the general area they wanted; they could also tilt and swivel it in any direction.

The radiation emitter was mounted on the end of another robotic arm.  The arm itself was repurposed from the automotive industry, where it’s used in assembly plants.  It was BIG, and had a number of complex joints that could pivot in several directions, so it was able to move the emitter all around the bed.  The radiologist told me that the system has 1 mm accuracy. 

The only hard part was an extremely restrictive diet.  Anything that causes gas or bloating can cause organs to shift and make it harder for the software to follow the treatment plan developed by the oncologist.  And I was only allowed to have clear liquids after lunch, until the following days treatment.

The treatment sessions themselves were actually restful.  My radiologist dimmed the lights in the room, and I let my mind wander, or slept a bit.  The robot went through the same sequence every day, so after a couple of days I knew what to expect.  As it neared the end of the sequence on Friday, my final day of treatment, I actually felt a bit sad that I wouldn’t be seeing my “buddy” again.

SBRT can be used for different types of cancers, not just prostate, and major medical centers across the country now offer the treatment.  Despite that, many doctors don't seem be be aware of the option. The urologist who initially diagnosed my cancer did not even present this as an option.

I wanted to share this so that others know about this amazing treatment option (if your condition meets the criteria for SBRT).