lytic bone lesion in a cat- biopsy or amputation?

Re: lytic bone lesion in a cat- biopsy or amputation?

Anthony Todd — Wed, 12 Mar 2014 16:18:30 GMT

[quote user="Yantha Smyth"]The owners are concerned how the cat would cope with 3 legs, but even if it is a front leg I understand they can adapt pretty well.[/quote]

Quite often ,with amputated front or back limbs in dogs or cats, all I ever noticed was a sort of strange walk.

Only on a second good look did I realise the animal only had 3 legs!!!!

They all coped without a care in the world; I'd advise it every time!

Re: lytic bone lesion in a cat- biopsy or amputation?

Hannah Wynne Richards — Wed, 12 Mar 2014 14:43:27 GMT

When I have owners saying that, I tend to resort to maths. Tell them if we lose a leg,we lose 50% of our legs, cats and dogs only lose 25%

They usually find that comforting

Wynne

Re: lytic bone lesion in a cat- biopsy or amputation?

Yantha Smyth — Wed, 12 Mar 2014 11:26:07 GMT

Thank you everyone for your input. Although I suspect the likely outcome will be FQ amputation, after discussion with owners, and colleague and taking into account the opinions on the forum, we have elected to proceed with biopsy first, so we at least know what we are dealing with before taking it further. The owners are concerned how the cat would cope with 3 legs, but even if it is a front leg I understand they can adapt pretty well.

Re: lytic bone lesion in a cat- biopsy or amputation?

HMC — Tue, 11 Mar 2014 18:50:47 GMT

[quote user="Utlendigur"]

[quote user="Yantha Smyth"] I am worried that biopsy could easily result in a pathological fracture during or after procedure[/quote]

In which case the decision re amputation would be made for you - as long as the owners know it is a possibility beforehand...

[/quote]

That's what I was going to say!

Re: lytic bone lesion in a cat- biopsy or amputation?

grumpyoldman — Tue, 11 Mar 2014 18:12:41 GMT

[quote user="Anthony Todd"]I'm always worried when the animal's insurance status seems to be a key factor in the diagnosis and treatment protocol.[/quote]

That is a very valid point ,it can cloud the clients thinking just as much as the vets. Another vet in our practice had one of thee recently and worked it up and gave the client the same options (there was more of a mix of osteogenesis and lysis and periosteal lifting) . Crazily they decided to seek the advice of the owner of a cat rescue who also had more than a few fingers in the pie at another local practice. The result was the cat having just its proximal humoral head amputated leaving its limb swinging free and useless with nothing between it and the scapulae. THe cat then hopped about having monthly depo injections for several months until a mass reappeared at the site of the previous surgery , The client reappeared asking if we could complete the amputation as originally planned ,but by then it had already invaded the chest wall and beyond . I did question the logic of removing just the proximal humerus in the face of the radiographic findings ,but was told that the other practice owner said she would make her vet do something else for them . I did look it up and apparently there is a technique for this type of partial limb salvage in Slatter following a favorable histopath result but it was not something I had come across before .

Re: lytic bone lesion in a cat- biopsy or amputation?

Anthony Todd — Tue, 11 Mar 2014 15:11:06 GMT

[quote user="Yantha Smyth"]The cat is insured, and is only 4yr8m.[/quote]

I'm always worried when the animal's insurance status seems to be a key factor in the diagnosis and treatment protocol.

Best diagnostics and or treatment are just that; if the owner can't, or won't, pay for the best, then go for plan B.

I don't think cost should enter into the primary process at all.

Trouble is there now is a tendency to confuse the best diagnosis or treatment with the most of both.

Re: lytic bone lesion in a cat- biopsy or amputation?

Utlendigur — Tue, 11 Mar 2014 14:27:00 GMT

Quick google

ACVS site - "Primary bone tumors are uncommon in cats. Unlike dogs, where the majority of primary bone tumors are malignant, up to a third of feline bone tumors are benign. Osteosarcoma is also the most common bone tumor in cats, but the behavior of this tumor type is less aggressive than in dogs." and "In contrast to dogs, cats with appendicular osteosarcoma have a low metastatic rate (less than 10%) and the median survival time following amputation alone is over 350 days (and up to 4 years)."

Re: lytic bone lesion in a cat- biopsy or amputation?

Chris Milligan — Tue, 11 Mar 2014 13:56:55 GMT

[quote user="robloxley"]

I have had much more encouraging results with amputation as a sole treatment for bone tumors in cats, with one still running around over 5 years down the line

[/quote]

what did the histology come back as? I've heard stories of such cases - there are always exceptions to the rules. My experience of cases of cats-with-bone-tumours is too limited to make an assessment of one treatment option over another

Re: lytic bone lesion in a cat- biopsy or amputation?

Rob Loxley — Mon, 10 Mar 2014 23:45:19 GMT

[quote user="Chris Milligan"] if it IS a bone tumour it's very likely to have spread already anyway[/quote]

I have had much more encouraging results with amputation as a sole treatment for bone tumors in cats, with one still running around over 5 years down the line

Re: lytic bone lesion in a cat- biopsy or amputation?

Utlendigur — Mon, 10 Mar 2014 15:00:25 GMT

[quote user="Chris Milligan"]but this is a young cat so my money would be on an infectious process rather than a neoplastic one[/quote]

Another anecdote alert.

I saw a 18mnth old DSH with sudden onset lameness and swollen stifle. Given the age and history I assumed trauma and it settled quickly on nsaids. It then recurred, again with large stifle effusion. Xrays showed multiple punctate lucencies around joint margin, joint tap was pure blood and synovial membrane biopsy came back as haemangiosarcoma. I amputated the leg but gave fairly guarded prognosis (especially as it belonged to a neighbour - as these sort of cases tend to). Cat was fine for about 10years until the tumour recurred around the amputation site and it was pts.

Re: lytic bone lesion in a cat- biopsy or amputation?

Chris Milligan — Mon, 10 Mar 2014 14:43:15 GMT

I think it would be foolish to rush to amputate this; yes there is a lytic lesion but you can't say anything beyond this. Whilst a bone tumour would be one potential cause of this you have to consider other causes - especially osteomyelitis, and - less likely - vascular damage. A particularly vicious bite wound can cause osteomyletic changes, as can fungal disease. the lack of periosteal reaction/fluffing is a little odd.

You can safely take a small core biopsy of bone - even a pathological fracture is preferable to unnecessary amputation in my book. if it IS a bone tumour it's very likely to have spread already anyway. The other possibility would be a bronchogenic metastasis to the bone as this is one of the most common bone tumours in cats, but this is a young cat so my money would be on an infectious process rather than a neoplastic one.

Re: lytic bone lesion in a cat- biopsy or amputation?

Anthony Dennison — Mon, 10 Mar 2014 10:36:02 GMT

Anecdote alert:

I saw a Maine Coon last year that went a little lame after jumping off a high surface. Responded to meloxicam, but then a firm swelliogn appeared at the elbow. Not the most compliant of owners at the time, so I kept asking to re-see it but he would wave me off and tell me it wasn't too bad, she was getting around.

Seen 1 month later, swelling now the size of a satsuma. We took radiographs and there wasn't really an elbow joint left, lytic lesion had made it almost unrecognisable. Saw a specialist who recommended amputation, the owner declined as the cat could still walk around ok (surprisingly!)

Cat declined over the next 6wks or so and died the night before it was due to come in for PTS.

Re: lytic bone lesion in a cat- biopsy or amputation?

Malcolm Ness — Sun, 09 Mar 2014 22:19:56 GMT

Neoplasia top of the list but certainly not the only thing on the list.

Biopsy is indicated - lateral approach and go deep - far too many biopsies of bone lesions yield nothing more than inflammatory tissue or normal bone so you have to get well into the lesion.

Generally, bone tumours in cats carry a much better prognosis than the same tumour in dogs. A fore-quarter amputation would be best here if amputation is needed given the very proximal location of the lesion.

Re: lytic bone lesion in a cat- biopsy or amputation?

Glenn Hodgson — Sun, 09 Mar 2014 20:10:56 GMT

I'd be inclined to biopsy 1st

Re: lytic bone lesion in a cat- biopsy or amputation?

Christopher Saul — Sun, 09 Mar 2014 19:42:08 GMT

FNA may be possible as a first step; though admittedly if whatever it is proves to be poorly exfoliative, then could be unrewarding (so long as owners prepared for this then not a major issue). However it is fairly low risk and low difficulty so I would start with this.

One point to mention is that osteosarcomas are rare in cats but in general seem much less aggressive than in dogs. I have personally only treated one case myself; he survived almost 4 happy years post amputation.

Re: lytic bone lesion in a cat- biopsy or amputation?

Yantha Smyth — Sun, 09 Mar 2014 19:10:37 GMT

[quote user="mariette asselbergs"]

What does a biopsy really add to the treatment options?

If it is not cancerous but a bone cuyst, would you keep it on metacam maintenance?

How old it the cat? Insured, how far does owner want to go?

Mariette

[/quote] The cat is insured, and is only 4yr8m. Only one of the owners saw X-rays on discharge of the cat, and they were shocked, but took photos of X-rays to take home and talk with partner. Mentioned biopsy, and amputation; on some views The lesion appears quite extensive, so I am thinking even if benign that it may only be a matter of an impact jumping or running that could result in collapse of the area- hence wondering if going straight to amputation might be the way to go. To be honest I was quite surprised to see this lesion, as I was expecting to find either nothing, or maybe some mild arthritic change in the elbow that had been exacerbated by activity/impact. There has been no pyrexia, or heat, swelling, soft tissue reaction, but the cat has recently moved house and been bullied recently- lameness noticed after seen running away from a bully cat. So I did wonder if osteomyelitis may present like this, but wasn't really sure.

Re: lytic bone lesion in a cat- biopsy or amputation?

mariette asselbergs — Sun, 09 Mar 2014 18:52:35 GMT

What does a biopsy really add to the treatment options?

If it is not cancerous but a bone cuyst, would you keep it on metacam maintenance?

How old it the cat? Insured, how far does owner want to go?

Mariette

Re: lytic bone lesion in a cat- biopsy or amputation?

Robin Grimmer — Sun, 09 Mar 2014 14:29:35 GMT

Biopsying that shouldn't be too difficult. I'd want to do that first.

Re: lytic bone lesion in a cat- biopsy or amputation?

Utlendigur — Sun, 09 Mar 2014 10:19:16 GMT

[quote user="Yantha Smyth"] I am worried that biopsy could easily result in a pathological fracture during or after procedure[/quote]

In which case the decision re amputation would be made for you - as long as the owners know it is a possibility beforehand...

Is it pyrexic? Another differential might be osteomyelitis.