Acromegaly Diagnosis, Treatment options

[Jack & Jamie]

Hello,

I'm looking for advice and support in making a treatment decision for my boy, Jack. He is 15yo and was diagnosed with diabetes 12/24. Recently I had them do the IGF-1 test which confirmed acromegaly >1200. He is currently on 7.5units of Lantus 2x daily. He also has high blood pressure and is on amlodipine. They did a chest x-ray last year, to see if the hypertension caused any damage to the heart, which showed the heart was slightly elongated, but not "enlarged." Ultrasound in January 2026, showed slight aging in his organs, nothing significant. They did notice thickening of the intestines, which at the time, they thought was either IBD or cancer. Now with the IGF-1 results, I suspect the GH was the trouble maker for all of these signs. He also has raspy breathing when he purrs or is snoring, which they previously couldn't pinpoint what was causing this. Now it seems obvious that the soft tissue in his throat has thickened from the GH as well. Overall, he is a very happy cat, considering his ailments.

I am struggling to make a decision on how to treat Jack. The priority is quality of life. These are the options the vet discussed. His internal medicine vet is at BluePearl in Tampa. First step is to do an echocardiogram to determine if he is a candidate for anesthesia and it will give us an idea if his heart has changed since the xray. Giving medication at home seems like it would be the most comfortable for him, but I worry it may not work and he will end up suffering down the road, from the mass growing or GH causing issues. SRT sounds encouraging, but 3 consecutive days of anesthesia could be very hard on him.

1. Surgery- I've basically ruled this out due to age, risk factors, recovery period.
2. Definitive Radiation therapy- (mon-fri for 20 treatments) This seems too aggressive for his age/ risk factors.
3. Stereotactic Radiation Therapy- (3 days in a row, if the CT shows he is a candidate.)
4. Palliative Radiation Therapy- (2x/week for 2 weeks, then 1x/week for 2 weeks)
5. Cabergoline- My first instinct was to go this route, so he didn't need to be sedated or have the stress of going to the vet for radiation. My concern is the mass continuing to grow and the quality of life he will have if the mass impacts his brain. I am worried he will suffer without me knowing he is in pain, or neurologically challenged. Also, what if we treat him with this medication for 3 months and it ends up not working, we will have wasted time with his body still flooded with GH.
6. Pasireotide Injections- Mimics the "off switch" for GH, but can cause GI upset.

Thank you in advance for your time, support and knowledge!

Best,

Jamie & Jack

 

[Wendy&Neko]

Hello and welcome. Sorry to hear about the diagnosis, but it's good to know so now you can plan what to do next. My suggestions are to consider options 3 or 5 and rule out the rest, some of which you've already done.

Surgery, done in limited locations and expensive with higher risk factors, though those that get through it have better outcomes. If you lived in the UK it'd be a reasonable option due to expertise there. The 20 treatment radiation therapy is a lot of anesthesias for an acro kitty given tendency to heart issues, much less any older kitty. Option 4 - never seen that offered for acro, seems like a waste of money. It's an option typically offered for cancers. Option 6, very expensive with very little experience in it, primarily due to cost of the drug.

Neko had SRT twice. Depending where you live it can mean a bit of travel and 2-4 radiation sessions. Cyberknife is a variation on SRT but offered in few places. It has slightly better outcomes - and costs more. Costs of SRT is quite high, way higher than when Neko went for it. Private facilities charge way more than university vet teaching schools. SRT doesn't have a lot of impact on IGF-1 numbers. The growth can come back (as it can with any of the options), which is why Neko had her second SRT three years later. This is not common, but does happen. Neko did have good QOL for almost 5 years.

Lots of people try cabergoline here - it is definitely the most cost effective and no travel required. It does seem to improve the acro symptoms some. But it does do better in some cats that other, supposedly those with smaller tumours. Which you can't find out with a pricey CT scan, and anesthesia. Most people don't bother with the CT, just try it. It's not uncommon for cats to take 3 months for the effects to be really seen, but we've also had a couple cats that went off of insulin in 1-2 weeks after starting. You can start cabergoline and if it doesn't seem to be improving anything, can switch to another option. I've seen a couple people try that. You do have to taper down the cabergoline before stopping it.

You might want to read this paper, on quality of life for various acro treatment options from an owners point of view. This was a research study done by some students in Europe who also posted the questionnaire here a number of years ago. I can point you to papers on most of the other options (except 4) if you wish.

 

[JL and Chip]

I agree with everything Wendy said.

I also agree with your IM that first step should be an echocardiogram. The results could rule out certain options, therefore saving you some mental handwringing.

We too went the SRT route (back when it was significantly less expensive). Sadly it was over a year between diagnosis and SRT, which might have been detrimental.

The anesthesia risk is a real thing, especially if there’s already kidney impairment. Does Jack have diagnosed kidney issues? High BP is often secondary to kidney insufficiency in cats, thus my question.