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Is CK treatment better -- everyday or every other day -- for 5 days?
SteveK364
Posted: Monday, July 16, 2018 4:54 PM
Joined: 6/26/2018
Posts: 70


Are CK treatments more effective, or have fewer side effects when given every other day -- versus everyday for 5 days? Also, from what I read, patients receiving a dose of 35gy seem to tolerate the treatment better than those who receive a 36gy dose. Any thoughts? Thanks.

SteveK364


JAV
Posted: Tuesday, July 17, 2018 4:48 AM
Joined: 10/29/2010
Posts: 801


There was a study done way back around 2010 that claimed less short term side effects with every other day treatments. I requested every other day treatments and that's what I received. The only short term "complication" I had was about after the second treatment, I would have a little burning sensation when urinating. That only lasted a few days after the treatments were completed. Don't know 35 Gy vs. 36 Gy. I believe the BED ( biological eqluivaent dose ) would be over 90 Gy for both.

Treated with CK 4-2011.  Gleason of 3+4 , PSA 3.7 , two cores positive, 5% & 12%
 PSA on 7-13 0.3  PSA on 11-13 0.3 PSA on 5-14   0.3  
PSA on 7-14   0.2 PSA on 11-14  0.2 PSA on 3-15 0.2
PSA on 7-15, 0.2 PSA on 7-17 0.1 PSA on 1-18 0.13
DXM
Posted: Tuesday, July 17, 2018 9:38 AM
Joined: 9/10/2016
Posts: 20


My radiation oncologist, Dr Simpson of Colorado Cyberknife, does the 36.25 Gy protocol (unless there is a well located tumor that will get a radiation boost). Every other day treatments are the most common, but apparently Cyberknife guru Dr. Alan Katz does the five treatments on consecutive days with minimal side effects. There is a place in Canada that does one session per week. My take is that the interval between treatments has no effect on the efficacy. However if your AUA score is poor and/or your gland is smack dab up against the rectal wall you might ask if a longer treatment interval would help the bladder and/or rectum recover better with longer intervals.

DAMorris
radsrus
Posted: Tuesday, July 17, 2018 2:21 PM
Joined: 10/10/2008
Posts: 4435


There is no compelling evidence that treatment every other day is better or worse. Lots of patients have been treated each way, and there is no clear difference. Dr. Chris King reported better rectal tolerance with every other day, but there are reasons to doubt those results and it is of little importance now that we have Space OAR. If you are worried about rectal complications then insist onSpaceOAR. As for dose, again there is no clear winner. We have just reported 100% control with minimal side effects using 9.5x4, but others have done well also with different doses. Furthermore, it is difficult for patients to compare doses, because it depends on where the dose is quoted. A dose quoted ash the expanded margin may be exactly the same as a higher dose quoted at the prostate capsule.

Clinton A. Medbery, III, M.D. Southwest Radiation Oncology buddy@swrads.org
JAV
Posted: Tuesday, July 17, 2018 2:29 PM
Joined: 10/29/2010
Posts: 801


Dr. Medberry : Thanks for that clarification of dose specified for prostate capsule + margin vs. just the prostate capsule.

Treated with CK 4-2011.  Gleason of 3+4 , PSA 3.7 , two cores positive, 5% & 12%
 PSA on 7-13 0.3  PSA on 11-13 0.3 PSA on 5-14   0.3  
PSA on 7-14   0.2 PSA on 11-14  0.2 PSA on 3-15 0.2
PSA on 7-15, 0.2 PSA on 7-17 0.1 PSA on 1-18 0.13
JAV
Posted: Tuesday, July 17, 2018 2:38 PM
Joined: 10/29/2010
Posts: 801


BTW, I couldn't find any info at this Forum about Space OAR, but found this info at another website : What is SpaceOAR®? SpaceOAR® (OAR stands for “organ at risk”) System is a temporary, injectable gel designed to protect the rectum from radiation exposure in men undergoing radiation therapy for prostate cancer. On average, hydrogel creates about a half-inch (or 1.3 cm) of space between the prostate and rectum. This technique is designed to allow physicians to treat the prostate with less radiation exposure to the rectum and fewer complications. It received U.S. Food and Drug Administration (FDA) approval in April 2015. How it works The SpaceOAR poly-ethylene hydrogel is injected between the rectum and prostate during a minimally invasive procedure to increase the distance between those organs. The gel stays in the body for about three months, and then is naturally absorbed and eliminated from the body in the patient’s urine. By separating the prostate from the rectum, SpaceOAR hydrogel is designed to reduce radiation exposure to the rectum during treatment and may reduce, or possibly eliminate, damage to the rectum and associated side effects. Some potential side effects include bowel problems, urinary incontinence and other bladder issues.

Treated with CK 4-2011.  Gleason of 3+4 , PSA 3.7 , two cores positive, 5% & 12%
 PSA on 7-13 0.3  PSA on 11-13 0.3 PSA on 5-14   0.3  
PSA on 7-14   0.2 PSA on 11-14  0.2 PSA on 3-15 0.2
PSA on 7-15, 0.2 PSA on 7-17 0.1 PSA on 1-18 0.13
 

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