How long is FISH test is valid?

[Bowie1957]

Does anyone have an idea on how long the FISH test is valid and how often do we need to repeat it. I had one done in November 2017 and my oncologist want me to have another one soon.

[cajunjeff]

I do not know that there is any set length of time a FISH test is valid. Since FISH markers can change over time, a FISH test is just a snapshot of that day.

I think what you might be asking is how often should a FISH test be repeated. I think in very general terms that would be once at diagnosis and then once again when about you treat. Since your FISH results do help inform treatment decisions, you would want up to date results before deciding on treatment.

There are any number of reasons a doctor might want to repeat FISH testing at some other times too, but in general I think it would be once before diagnosis and once before each treatment.

In a clinical trial it would likely be tested more frequently to learn how treatment is impacting FISH.

[Bowie1957 in reply to cajunjeff]

Many thanks. Im considering starting treatment since my lymphocytes are doubling every six months. Im starting to feel discomfort in my abdomen. My spleen was 15 centimeters 8 months ago. Im feeling other B symptoms. Btw. My first FISH test was negative, but in less than two years i went from a 7k lymphocytes count to 65k. We’ll keep you posted. Thank you all for your help.

[Bowie1957]

Thanks Scott. Very helpful

[lankisterguy Volunteer]

Hi Bowie,

The issue/concern is that a current/valid FISH is available just before starting treatment. If there are multiple clones in your blood, the stronger, more resistant ones can become dominant. This is primarily important if Chemo like FCR is being considered for you. Deletions like 17p are resistant to Chemo and tend to appear more often after years of watch & wait.

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If the proposed treatment is one of the new targeted therapies like Ibrutinib/Imbruvica, Idelalisib/Zydelig, or Venetoclax/Venclexta, the FISH is not nearly as significant, but the test usually just requires one more tube of blood, so the only concern is the cost. If you have a copay you may want to question the doctor why he/she wants the test. If no treatment decisions will change based on the test results, it may only be curiosity. The doctor should be willing to explain the reasoning fully- in the USA you have a right to know.

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BTW- there are some NGS (Next Generation Sequencing) tests to determine if you may be resistant to Ibrutinib, and even some experimental tests to look for resistance to Venetoclax, but these are not often used before treatment and by usually only in major research centers.

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Len

[Bowie1957 in reply to lankisterguy]

Yes, my doctor is favoring Ibrutinib, but I have been holding off as I was not experiencing much of the B-Symptoms, except or the doubling time. My plan is have another Ct scan and then have another FISH, then I will decide on a second opinion if my Dr insists on Ibrutinib. Will keep you all posted. Thanks you for your good reply.

[lankisterguy Volunteer in reply to Bowie1957]

Ibrutinib is becoming the new gold standard, and many of the top CLL experts would probably skip the FISH and the CT scan and go for Ibrutinib, only when you have B symptoms.

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The only thing that doubling time affects is how frequently you should have blood tests and exams.

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Starting with Ibrutinib and then doing MRD tests and CT scans after several months or one year, while consulting with a top CLL expert might be a way to keep costs down.

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Len

[Bowie1957 in reply to lankisterguy]

This is very helpful. Many thanks

[GMa27]

Seems too soon to get another except if ur ready for treatment. Ask your doctor why again? 💕

[WinJ3]

I had FISH test when diagnosed and another one eight years later near treatment.

[Bowie1957]

Scott, how and why did you start treatment?

[Bowie1957]

I am glad you are feeling much better and hopefully you can get this CLL completely under control. I have experienced some fatigue and sometime lack of energy, but every time I felt this way, I put on my walking shoes and force myself to walk few miles, even when the temperature was sub zero. Another thing I was able to do, was to reduce stress in m life and at work. It was tough, but now manageable.This did not help my blood count, it kept on doubling every six months. Now, I am experiencing some discomfort in abdomen, but not too painful. Everything else seems to be still ok. I still walk between 5 to 12 miles per day. It helped my stress level and I noticed that after every walk, my slightly enlarged neck lymph nodes shrunk in size. However, I am still considering going with he miracle drug, It’s a matter of time, next month or November by the latest. I needed to control the psychological aspect of CLL. BTW, have you felt lonely and that you are so alone in this fight, and how did this feeling change after you started treatment?

[Bowie1957]

Well wishing you the best and thank you for taking the time to respond to my questions. Will keep you posted

[MsLockYourPosts Passed Volunteer]

The standard advice for some time was to have a new FISH done before making any treatment decisions. That seems to be less of an issue now that the newer, non chemo drugs are more readily available in the US, and, for many doctors, are becoming the standard of care.

If your doctor is considering FCR or BR vs ibrutinib I would insist on a new FISH. If true chemo is off the table a new FISH would probably not give your doctor information needed re: treatment choices, but he might feel that the information would be useful for other reasons, especially if he is a researcher.

[LovecuresCLL]

I think the only time you need additional or repeat FISH testing is if your disease is progressing with or without treatment. It is see if you are developing additional mutations besides the ones your tumor already has. They need to compare to your old profile.

I would not worry but I would request NGS next generation sequencing . It is better way than FISH to determine what mutations are present.

Tell your doctor you want NGS to look for mutations rather than repeating the FISH.

[Bowie1957 in reply to LovecuresCLL]

Thanks

[LovecuresCLL in reply to Bowie1957]

Yes just say “Doc why not “next generation sequencing”? Isn’t it more sensitive and specific?”