CT scan 2015 info update #1

CT scan 2015 info update #1

Hi all,

I have examined recent research in the long running debate concerning the risks vs benefits of CT (Computed Tomography) scanning, with focus on how it may relate to our CLL/SLL community. My opinion, reflecting that of many CLL specialists and medical researchers, is that the public is being subjected to far too many unnecessary CT scans thus it prompted me to write a series of 15 essays on the subject. (see archive) My concern for the CLL/SLL community, as a potentially more vulnerable population, due to the risks from CT ionizing radiation rests largely in the fact that we are often subjected to frequent CT scans and being an immunocompromised group, it suggests we are also poorer at repairing double stranded DNA breaks from CT ionizing radiation. Further more, there has not been a study on a CLL/SLL population to confirm or refute the risk contention. The study I am about to review comes as close as any study so far in shedding light on this issue but has some deficiencies as a direct comparison to the CLL/SLL experience.

Before reading about the study findings it is advised to consider the following: We cannot directly compare the findings from this study to our CLL/SLL experience with CT scans because this study has a more narrow goal to assess CT scanning risk for increased SPM (Secondary Primary Malignancies) in a group of aggressive NHL (Non Hodgkins Lymphoma) patients who have been given therapies with curative intent. While this study does relate more closely to CLL patients that have faced or are facing curative therapy attempts after developing RT or RS (Richter's Transformation or Syndrome) it is quite different from the contexts of most frequent CT scan use in CLL/SLL periods of Wait & Watch or Clinical Trials where most patients are slowly progressing (W&W) or not achieving a CR (Complete Response) in Clinical Trials.

The justification for more frequent CT scanning in a Clinical Trial situation is based on a drug developer's need to prove efficacy by documenting non-palpable internal lymphnode response to a study drug and early detection of relapse often first seen first in internal lymphnode enlargement.

Although the study was a nationwide effort involving a large number of patients (4,874), it involved a Taiwanese population with potentially different genetic and or environmental characteristics that could muddy the result if applied to largely Western Caucasian populations more prone to CLL/SLL than Asian populations. Because the NHL study patients all received a very harsh Chemo based therapy (CHOP) it is possible that the therapy in combination with ionizing radiation from CTs had an important role in the findings as opposed to the many less toxic therapies used in CLL/SLL Clinical Trials where frequent CT scanning is mandated. The study findings, about to be revealed, have looked at CT scan effects in the context of a presumed cure whereas CLL/SLL patients are scanned in W&W (Wait & Watch), again after therapy and most frequently in Clinical Trials where disease is still present.

Other short falls of the study from a CLL/SLL standpoint are: Given the study was done in Taiwan we are not given any information as to the dosing of ionizing radiation used per CT scan. The range can be significant and you can read about this in my CT scan essay series #5. We are not given the average or age range of participants. CT scans in the study might be administered in greater number over a shorter period of time than would be the case in a CLL/SLL patient experience. Number of scans in the study range from 5 to 12. Study states: “It is conceivable that liver tumors are related to the highly prevalent Hepatitis B infection and its associated cirrhosis in Taiwan.”

While I agree with the apples vs oranges criticism of some in applying the study conclusions to our situation, I feel there is value to bring this study and its conclusions to the attention of the CLL/SLL community. I mentioned the caveats as I see them and have pointed out in my CT essays that there has not been a study in CLL/SLL to discover whether the condition of having CLL/SLL with its immune suppression and high frequency of CT exposure contributes to a secondary cancer risk or is overridden by greater benefits. The need to have imaging, from a research perspective, is greater with the newer KIs (Kinase Inhibitors) such as Ibrutinib, ACP-196, Idelalisib etc. but the risk probability of SPM from frequent CT scanning is also increasing with KI (kinase Inhibitor) use as people who would otherwise have died, are now living longer. Remember, CT radiation is cumulative! The study is the closest yet to defining a potential risk for increased SPM in our guys from frequent scanning.

Below is the name of the study and links to the abstract & two lay articles.

“Frequency of surveillance computed tomography in non-Hodgkin lymphoma and the risk of secondary primary malignancies”: Sheng-Hsuan Chien et al.

onlinelibrary.wiley.com/doi...

Lay articles about the study - link goo.gl/TJejBf and in Medscape medscape.com/viewarticle/84...

Highlights of the research:

Study results of 4,874 Patients selected for consistency of relevant factors found: “... patients receiving more than 8 CT scans had significantly higher risk than patients exposed to fewer scans, with secondary cancers most frequently arising in breast, stomach and liver.” Note: we are not talking about skin cancers here!

“The risk of SPM [Secondary Primary Malignancies] increases 3-5% per additional CT scan.”

Divergence between fewer & more SPMs began as early in the findings as 2 years after the number of CT scans documented as between 5 and 12.

This finding could be the most revealing because of the relatively short time frame and because it is related directly to the number of CT scans.

“Among the 180 SPM cases identified in this cohort, the most commonly observed subtypes were cancers originating from the liver and biliary tract (n=35)...”

An Interesting but not surprising finding: “... cancers of the stomach, breast and liver were significantly predominant in those patients receiving more CT scans, implying a high risk in the overlapped body sites.” [emphasis added]

Study Conclusion: Routine surveillance CTs are of limited value in detecting asymptomatic early relapse with NHL patients having received therapies with the intent for cure and does not contribute to better overall survival.

This study addresses the purpose for frequent CT scans with the specific goal of catching asymptomatic early relapse and should not be confused with the same goal of Clinical Trial frequent scanning with the intent to document experimental drug efficacy, other impacts and disease progression in CLL/SLL patients still harboring varying degrees of tumor.

The single most interesting finding was the detection of a trend for increased SPM beginning as early as 2 years in the patients having received 8 to 12 CT scans as opposed to those patients having received less than 8 CT scans. This study begs the need for a CLL/SLL patient study with age, gender, CT frequency, total number and dosing parameters examined. This study demonstrates another reason to eliminate any overlapping of CT scans when patients in Clinical Trials are typically given double or triple scans in one session.

WWW – refused 6 CT scans but am currently up to 24 CTs.

Photo is of a new building for housing air-conditioning needs of the newly opened James Cancer Hospital at OSU Medical Center in Columbus Ohio, USA. The colored light is from dichromatic glass projections that change the colors as one moves relative to the source of light, artificial or sun.

12 Replies

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  • Hi WWW, My RESONATE-2 study is to close in May and we have been urged to go on to the extension study which is for 5 years less the time already put into the study. In my case that will be 3 years to do.

    I have been told that the scans have been reduced to 6 monthly periods. I did not take up the option to go onto the extension and said that I would only do that if I could have MRI scans instead. After much to-ing and fro-ing I have heard from my research nurse today that it has been agreed that I can have MRI scans if I go onto the extension.

    I am now awaiting a similar result for a scan due on 14th April. So, it pays to persevere. They would not entertain the idea in the first 2 years but now there has been a change of heart. Incidently, I found an article re ionising radiation to the pelvic area can cause erectile dysfunction which can be permanent. I didn't see that in the patient document!!!!

    I still have had 7 CT and 1 PETscan that could rebound on me. I see you are up to 24!! that is an awful lot!!!

    Thanks for following this up, it's been a long haul.

    Mike

  • Hi Mikey47,

    Thanks for your feedback and happy to hear you are part of the proactive movement to address the CT scanning issue.

    I am a patient with a PM (Pacemaker) which is not conducive to MRI. I have been an active welder and grinder of ferric metals which raises the risks of having an MRI for me.

    For clarification of the number of CT scans: Not everyone knows that in at least the Clinical Trial setting for CLL patients we are receiving at least two and many times three separate scans in one session. My 24 scans were mostly comprised of three per session. The bad part of these triple scans are the two areas of overlapped organ tissue that gets twice the radiation of one scan.

    If you can please send a link to the article on ED as I am not aware of it.

    Good luck and may the CLL Bear stay in deep hibernation.

    WWW

  • WWW, yes, I didnt take the overlapping into account so I could have a higher count also,

    This is what I found: lymphoma.about.com/od/livin...

    Best Wishes

    Mike

  • I just lost a life long buddy to metastatic castrate resistant prostate cancer in which he had therapeutic radiation that did a number on ending his sex life. Thanks for sending the link but the ED is in the context of therapeutic, not imaging radiation.

    WWW

  • Sorry to hear of the loss of your buddy.

    Yes, it's therapeutic but surely the cumulative result of frequent scans could have a similar effect, couldn't it? I don't know the values of therapeutic radiation, probably much stronger?

    Mike

  • I had 30 Gy in 10 fractions of radiotherapy... it is roughly comparable to about 1500 abdominal/pelvic two pass CTscans.... of ~ 20 millisieverts

    I have a friend who is currently having 60 Gy... in 30 fractions

    Risk/benefit

    CTscan doses

    radiologyinfo.org/en/safety...

    Radio/Radiation Therapy

    cancer.gov/cancertopics/tre...

    Funny about MRIs... I was pulling iron filings out of my skin for months... 10 years as a tool and die maker... ;-)

    And then there is the gamma tagged MUGA scans.. Zevalin and so on, but that's a story for another day...

    cancer.net/navigating-cance...

  • Not sure how accurate this risk calculator is but if you missed it from my essay here it is. xrayrisk.com/calculator/cal... The difficulty in using this calculator in a CLL context of perhaps years of periodic CT scans is assessing age at the time of each scan and how that impacts the cumulative effects.

    WWW

  • Mikey47

    Therapeutic radiation is not only on a very different level of intensity but it is concentrated to a target tumor mass. The imaging scans of CT and PET are used to look at portions of the body so in a CLL Clinical Trial context all the body except peripheral limbs and the top half of the head are receiving radiation and repeatedly. Not so much worry for guys 70 and over but for a young man and especially a young woman 30, 40 and 50 years of age it is troubling when the need or utility for a scan is not medically justified.

    WWW

  • There is also non-targetted radiotherapy called TBI, total body irradiation, that is used in conjunction with chemotherapy, to clear the marrow prior to bone marrow or stem cell transplant... Again this is therapeutic not diagnostic and it is used prior to transplant for CLL.

    cancerresearchuk.org/about-...

  • Here's the link to part 1 of WWW's CT Scan series. It contains the links to all articles in the series:

    healthunlocked.com/cllsuppo...

    WWW are you going to add this article to your PDF document with all the previous articles? With the CLL Support Association website now available, we can include it as a download.

    Thanks,

    Neil

  • Certainly glad for your success on the trial and thanks from all of us for participating. Wondering if your insurance is helping out with the cost of the scans or does the trial it self absorbs that cost.

  • Hi may04cll,

    I got very lucky in that I was a small business owner but my wife worked for the county. I got county group health insurance through her. I do not know how individual private insurance responds to the requirements beyond the free Trial drug that are designated as "standard of care" to include the frequent scans. My insurance has covered all of those expenses though the frequent scanning is most definitely not standard of care. My Heme/Onc CLL specialist has never asked me to get a scan outside of the Clinical Trial and has voiced his dislike of CT use in all but the clinically indicated situations. It is best to ask your insurance provider to clarify and give assurance that all procedures designated as "standard of care" will be covered. That way you will or should get a written consent order stating what is to be standard of care if enrolling in a Clinical Trial.

    WWW

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