Insulin producing tumors-any experience

[Dreamwine60]

Has anyone had any experience in their cat having a tumor that produces insulin and throws their BG readings off? If so, how did you find the tumor? What sort of tests were run?

 

[Lisa and Witn (GA)]

Yes, when Spot (GA) started getting sick, I noticed that her BG levels dropped significantly so that she did not need insulin. It was not until several vet visits later that they found she had a huge tumor that was cancerous. I am not sure if benign tumors act the same way.

For her they were able to see the tumors in xrays. I lost her sister Tiger earlier this year also to cancer. They had to use an ultrasound to find her tumor.

 

[Wulfwin]

My cat Jason has a suspected insulinoma. He's been OTJ for 5 and a half years, and last year he had a hypoglycemic seizure. When it happened I didn't even consider that he might be hypo because he wasn't on insulin and had been eating normally. I happened to run his biannual bloodwork that day, and got the results about 2 hours after the seizure which showed low BG; I immediately tested him with my home monitor and found he was still in hypo numbers. My vet did an ultrasound to try to find the tumor, but wasn't able to see it. He couldn't think of any other possible causes for a hypoglycemic seizure in a generally healthy adult cat that wasn't on insulin. The only other possible way for us to diagnose it was to do an exploratory surgery but as the internal medicine specialist put it she wasn't about "to go poking at a 17 year old cat's pancreas" (which my vet and I agreed on), hence why Jason's tumor remains suspected instead of confirmed.

 

[Dreamwine60]

Thank you both. I guess that will be my dilemma also, have a 15 yr old cat undergo some type of surgery or let him eat what he wants until the end. He has lost so much weight. I am going to do one more curve on him with 2 different meters to rule out the bad meter/strip question and then we will see.

 

[BJM]

There was a cat here, Xuxu, who may have had an insulinoma. The glucose levels were erratic and using Lantus wasn't helping because glucose levels wouldn't stabilize due to the intermittent insulin from the tumor, thus the Lantus dose could not be stabilized.

Depending on where you are, if there is a university veterinary school, you might get a 2nd opinion there or, if you can afford it to go there, get a 2nd opinion from from veterinary endocrinologist Dr Mark Peterson his blog.

 

[Dreamwine60]

Thanks for the link, I actually ran across his first article while researching on the web. It influenced me in thinking this might be what is going on. There is some good reading here and I will continue to read some more of his articles.