Re: How soon to measure tg after surgery?

[Guest guest]

Alyssa Dodd says:

> How soon after surgery is a tg reading meaningful?

My endo didn't even measure my TG until 2-3 months after RAI.

ellen

--

mailto:ellen@...

[Guest guest]

I don't believe there's a reason your Tg would go down after surgery without an

ablation.

Since a Tg reading reflects the amount of thyroid cells in the body, it makes

sense that a Tg test isn't really meaningful until 6 months after RAI ablation.

Somewhat off the subject, I had my TT in February; in March (before my

ablation) my Tg was 6.70, then rose to 16.50 in April (after my ablation). I

don't know how long it took to drop after

that, but a year later it was undetectable.

-

NYC (TT 2/99 dx pap/foll; RAI 100 mCi 3/99 & 4/00; current TSH ~.06 on .225

levothyroxine)

[Guest guest]

I think Nick posted something from one of the doctors addressing this while

back. I remember 4 or 5 weeks post op is ideal for measuring TG but don't trust

my memory. Maybe the archives?

How soon to measure tg after surgery?

How soon after surgery is a tg reading meaningful?

before surgery tg was 100

3 days after surgery tg was 42.5

two weeks after surgery tg is still 42.5

I'd have liked it to have gone down some in between there. Is that too

soon to expect it to go down more?

-Alyssa in Idaho Falls

dx pap 10/00

TT mrnd 11/00

RAI 206 mci 12/00

tg unsuppressed 4/01 = 400

tg suppressed 7/01 = 100

tg suppressed 10/01 = 100

radical neck dissections 11/20/01

tg suppressed 11/23/01 = 42.5

tg suppressed 12/4/01 = 42.5

[Guest guest]

Alyssa Dodd says:

> But what about after surgery. I know RAi takes a while to kill it off

> but it seems like surgery would be immediate, maybe...

Alyssa,

As I said, my doctor didn't consider it a worthwhile test until

several months after my RAI. I had RAI about 8 weeks after surgery,

so it was 4-5 months post-op before my TG was tested.

Since TG is produced only by thyroid cells, it's reasonable to assume

that your TG would be lower after a TT than before. But since it's a

given that you have *some* thyroid cells left after surgery, a lower

number wouldn't tell you anything. TG measured after RAI gives an

indication of whether all of your thyroid was ablated, which is what

your doctor needs to know.

ellen

--

mailto:ellen@...

[Guest guest]

Alyssa Dodd says:

>

> But if they got all the thyroid cells out with the surgery wouldn't my

> tg go down immediately?

Alyssa,

If it were possible to remove every cell with surgery, we wouldn't

need RAI.

ellen

--

mailto:ellen@...

[Guest guest]

> But what about after surgery. I know RAi takes a while to kill it off

> but it seems like surgery would be immediate, maybe...

You are absolutely right - the Tg lowered due to surgical removal of thyroid

cells would be immediate (or almost immediate - I don't know, but I imagine

residual Tg might take a week or two to

leave the bloodstream).

But, as Ellen says, if they could remove every last thyroid cell with surgery,

we wouldn't need RAI ablations to finish off the job.

So, let's say your Tg was 500 before surgery (I'm making up these numbers for

the sake of illustration only), it might go down to 50 or even 20 after surgery.

A healthy reduction, but still not

good enough, so we call in the RAI to complete the job.

Clearer?

-

[Guest guest]

Tg should go down but not disappear after surgery. Tg half life is 3 to 4 days,

so it will take about two weeks to three weeks for it to reduce to less than .5

after surgery Most surgeons leave thyroid behind after surgery. If you have

your TSH suppressed the normal small amount of tissue will produce a small

amount of Tg, but not much. But most of us are not TSH suppressed immediately

after surgery. Your increasing TSH will cause this small remnant to produce

more Tg (although not enormous amounts). After RAI your Tg will rise for a

while, due to the Tg in destroyed areas of your thyroid being released, and then

it should fall to undectable.

However, Alyssa was ablated long ago. The fact that in two weeks after surgery

the Tg fell not at all from the immediate post-surgery Tg is cause for

suspicion that something was left behind.

(hurthle cell ca.)

Alyssa Dodd wrote: But if they got all the thyroid

cells out with the surgery wouldn't my

tg go down immediately? That's really encouraging that yours went up a

bit but then did go undetectable within the year. Thanks.

katiekabob@... wrote:

>

> I don't believe there's a reason your Tg would go down after surgery

> without an ablation.

>

> Since a Tg reading reflects the amount of thyroid cells in the body,

> it makes sense that a Tg test isn't really meaningful until 6 months

> after RAI ablation.

>

> Somewhat off the subject, I had my TT in February; in March (before

> my ablation) my Tg was 6.70, then rose to 16.50 in April (after my

> ablation). I don't know how long it took to drop after

> that, but a year later it was undetectable.

>

> -

> NYC (TT 2/99 dx pap/foll; RAI 100 mCi 3/99 & 4/00; current TSH ~.06 on

> .225 levothyroxine)

>

>

[Guest guest]

Yes the reason for my question really had to do with the fact that I was

ablated long ago (after the first surgery TT 11/00). My doc was not

planning to do another RAI now (after radical neck dissections 11/20/01)

because the RAI last time didn't seem to do any good anyway and it is so

hard for me to go hypo. Yes the fact that the tg didn't go down any

more between 3 days after surgery and 2 weeks after surgery worries me

too. Right now the doc is just waiting to do another tg in about 3

weeks. It's a nerve-wracking waiting time.

Kees wrote:

>

> Tg should go down but not disappear after surgery. Tg half life is 3

> to 4 days, so it will take about two weeks to three weeks for it to

> reduce to less than .5 after surgery Most surgeons leave thyroid

> behind after surgery. If you have your TSH suppressed the normal

> small amount of tissue will produce a small amount of Tg, but not

> much. But most of us are not TSH suppressed immediately after

> surgery. Your increasing TSH will cause this small remnant to produce

> more Tg (although not enormous amounts). After RAI your Tg will rise

> for a while, due to the Tg in destroyed areas of your thyroid being

> released, and then it should fall to undectable.

> However, Alyssa was ablated long ago. The fact that in two weeks

> after surgery the Tg fell not at all from the immediate post-surgery

> Tg is cause for suspicion that something was left behind.

> (hurthle cell ca.)

> Alyssa Dodd wrote: But if they got all the

> thyroid cells out with the surgery wouldn't my

> tg go down immediately? That's really encouraging that yours went up a

> bit but then did go undetectable within the year. Thanks.

>

> katiekabob@... wrote:

> >

> > I don't believe there's a reason your Tg would go down after surgery

> > without an ablation.

> >

> > Since a Tg reading reflects the amount of thyroid cells in the body,

> > it makes sense that a Tg test isn't really meaningful until 6 months

> > after RAI ablation.

> >

> > Somewhat off the subject, I had my TT in February; in March (before

> > my ablation) my Tg was 6.70, then rose to 16.50 in April (after my

> > ablation). I don't know how long it took to drop after

> > that, but a year later it was undetectable.

> >

> > -

> > NYC (TT 2/99 dx pap/foll; RAI 100 mCi 3/99 & 4/00; current TSH ~.06

> on

> > .225 levothyroxine)

> >

> >