Could radioactive iodine for thyroid cancer cause colon cancer?

[Skoliv]

I had to take some radioactive iodine for my thyroid cancer in 2008 and was wondering if this could have caused or at least helped create my huge cancerous polyp removed in 2014. Has anyone else ever taken this or heard of a relation between the two?

[CRguy]

Have never heard of a link personally. The Iodine (131 I believe ?) is usually concentrated into the thyroid as that is the preferred site of uptake for Iodine. The enduring "radioactivity" is usually of short duration. We use it for hyperthyroidism in felines and when the cats get treated they are housed in a "clean recovery" facility for only 5-6 days ... so I would not expect a CRC link in humans after similar treatment.

BUTT ... you know there has to be at least ONE !!!! ... most cats treated with hyperthyroidism are already very senior to geriatric and if any enduring effects were to arise they may not have been around long enough after treatment to show any new problems.

Interesting question, don't rule anything out and maybe check with your Oncs to see what they can add to the discussion.

Cheers
CRguy

[GrouseMan]

My former supervisor had the same treatment for thyroid cancer. That was I believe over 15 years ago, and he has not developed any secondary cancers as a result so far. Seeing as he also worked in Oncology drug discovery I believe he is VERY vigilant.

Its known that treatment for one cancer does often result years later in other cancers. But I believe that is becoming much rarer now that the treatments are becoming less destructive to ones healthy cells. Less radiation use now, more focused and CT scans with much lower dosages of x-rays compared to the old standard X-Rays one use to get 25 or more years ago. Movement away from really toxic DNA interculators.

The radioactive Iodine is very active but short lived in its radioactivity. In a matter of about a week to 10 days or so you can't detect it usually as it falls below background. But this is what makes it the best treatment for Thyroid cancer. It is taken up pretty selectively by the tumor and accumulates there even in its mets. Because of the intensity of the radioactivity it kills these tumor cells, but since its not taken up by normal non cancerous thyroid cells - it becomes pretty harmless to them quickly because of the radioactive decay to non radioactive elements and the much lower exposure due to it not being taken up by the normal tissues.

Its more likely a stray cosmic ray got your colon when you where high up in the atmosphere when you took a flight somewhere. Everyone try's to look for answers, but with cancer its a needle in a hay stack. way to many factors play into it. Most genetic, some environmental.

Good Luck

GrouseMan

[Lydia666]

I had thyroid and colorectal cancer because of a gene mutation. I did not have iodine treatment for the thyroid, surgery only.

[steiconi]

I had colon cancer, and 4 years later was diagnosed with thyroid cancer and had the radioactive treatment.
The colon cancer has not recurred in the 3 years since the treatment.

[Skoliv]

My former supervisor had the same treatment for thyroid cancer. That was I believe over 15 years ago, and he has not developed any secondary cancers as a result so far. Seeing as he also worked in Oncology drug discovery I believe he is VERY vigilant.

Its known that treatment for one cancer does often result years later in other cancers. But I believe that is becoming much rarer now that the treatments are becoming less destructive to ones healthy cells. Less radiation use now, more focused and CT scans with much lower dosages of x-rays compared to the old standard X-Rays one use to get 25 or more years ago. Movement away from really toxic DNA interculators.

The radioactive Iodine is very active but short lived in its radioactivity. In a matter of about a week to 10 days or so you can't detect it usually as it falls below background. But this is what makes it the best treatment for Thyroid cancer. It is taken up pretty selectively by the tumor and accumulates there even in its mets. Because of the intensity of the radioactivity it kills these tumor cells, but since its not taken up by normal non cancerous thyroid cells - it becomes pretty harmless to them quickly because of the radioactive decay to non radioactive elements and the much lower exposure due to it not being taken up by the normal tissues.

Its more likely a stray cosmic ray got your colon when you where high up in the atmosphere when you took a flight somewhere. Everyone try's to look for answers, but with cancer its a needle in a hay stack. way to many factors play into it. Most genetic, some environmental.

Good Luck

GrouseMan

Wow, very informative. Thanks!! True, I am just looking for answers... Maybe I just need the accept that I will never understand why.

Thank you all for your reply!