Approach to Mass Removal

Re: Approach to Mass Removal

Anthony Dennison — Mon, 14 Apr 2014 11:28:55 GMT

[quote user="James Laidlaw"]Could the initial antibiotic course have had an effect on the culture results?

[/quote]

We never cultured the original biopsy, it was just stained for acid fast organisms.

Re: Approach to Mass Removal

Bob Russell — Fri, 11 Apr 2014 09:53:45 GMT

Red star man back? All the posts seem quite reasonable to me and just confirm these can be buggers to sort out!

Re: Approach to Mass Removal

James Laidlaw — Thu, 10 Apr 2014 22:29:51 GMT

Could the initial antibiotic course have had an effect on the culture results?

Re: Approach to Mass Removal

James Laidlaw — Thu, 10 Apr 2014 22:29:50 GMT

Could the initial antibiotic course have had an effect on the culture results?

Re: Approach to Mass Removal

Elisabeth Knappett — Thu, 10 Apr 2014 21:39:04 GMT

What about a weird fungal infection? Cryptococcus? I believe this can start on feet/face with solid masses similar to your description.

Re: Approach to Mass Removal

Malcolm Ness — Thu, 10 Apr 2014 19:28:14 GMT

[quote user="Anthony Dennison"]I would really like to just chop it all out [/quote]

The problem is that until you can get a definitive dx, you won't know where to stop chopping. If the pathologist wants more biopsies it sounds like she/he isn't confident yet - what are the differentials that the pathologist is listing?

Re: Approach to Mass Removal

Anthony Dennison — Thu, 10 Apr 2014 14:15:27 GMT

Thanks for the replies. I've spoken to the pathologist that wrote the report, and he was disappointed that no acid fast organisms were found as he was sure that would be the cause. He's recommended further biopsies, inclucing one for culture and sensitivity.

I would really like to just chop it all out but the cat is not amenable to being faffed about with things like regular dressing changes, so it would be difficult to get it all out. I could possibly take the 5th digit off with the mass palpable on the dorsal aspect, and then a good and deep punch biopsy from the mass above the main pad.

Sound reasonable?

Re: Approach to Mass Removal

karen jones — Thu, 10 Apr 2014 13:32:06 GMT

We have a rotti with a similar lesion that was biopsies twice both times coming back with deep pyoderma , infection etc. eventually we removed the digit and sent that for histology a nd it came back as a squamous cell carcinoma, so maybe they're difficult to get representative samples on biopsy??

Re: Approach to Mass Removal

John Flynn — Thu, 10 Apr 2014 13:29:10 GMT

Anthony, did the signs clear or mostly clear while on the antibiotics and NSAID?

The inciting cause of deep pyogranulomatous dermatitis and panniculitis could be almost anything, but a foreign body would be on my list given your description.

Having said that, I've seen plenty of cases where the history "sounded" like a possible pedal FB and there was actually underlying neoplasia or other inciting cause (or indeed no cause ever identified).

Speaking to the pathologist sounds sensible, but even if there is not doubt about the histological classification of your biopsy, your biopsy may not be representative of the whole lesion.

I think you've a tough call to make and I don't find these cases easy:

1a) If it responded to the antibiotics and NSAIDs (or you think there is a reasonable likelihood that it responded), then one option is to use further antibiotics and NSAIDs for perhaps a longer period of time, e.g. 6-8weeks of amox/clav. If considering this, then a tissue biopsy for culture might be nice beforehand? The major downside is not if the lesion fails to respond, but if it does respond and then recurs afterwards (e.g. if is FB) or only partially responds...

1b) There's a remote chance that could be steroid-responsive.

2) Try to cut away the diseased tissue.

3) Investigate further (more biopsies, fancy imaging etc)

I had one memorbale one (in a dog) that I was convinced was a FB and kept recurring after long courses of antibiotics seemingly resolved it. Multiple biopsies only ever showed pyogranulomatous dermatitis and panniculitis. Eventually resected all the tissue involved and reconstructed the area and turned out to be a follicular hamartoma which had gone nuts, so appearances can be deceiving.

Re: Approach to Mass Removal

Bob Russell — Thu, 10 Apr 2014 13:01:20 GMT

I had one that was almost the splitting image of this. I treated it initially as a flight wound but it failed to heal. Impression smears were a bit odd so I biopsied it. It turned out to be a squamous cell carcinoma!

As my brain is completely addled I cannot recall more than this!

Re: Approach to Mass Removal

Richard Carter — Thu, 10 Apr 2014 12:50:19 GMT

any other signs of allergy? - swollen lips/ chin that sort of thing / eosin granuloma complex? - looks to me like self trauma following the pins and needles/ vasculitis following histamine release. Pododermatitis. Other dds already ruled out by your biopsy are that pads are a major site for metastasis of tumours.

Re: Approach to Mass Removal

Malcolm Ness — Thu, 10 Apr 2014 12:30:25 GMT

That doesn't really alter my thinking.

Re: Approach to Mass Removal

Anthony Dennison — Thu, 10 Apr 2014 12:14:26 GMT

Sorry, there is a small ulcerated lesion on the main pad on the underside, tried to upload a picture of it earlier but it didn't play ball. Now using Chrome and it's worked;

Re: Approach to Mass Removal

Malcolm Ness — Thu, 10 Apr 2014 11:35:53 GMT

There seems to be a mis-match between the clinical description/photograph on one hand and the path report on the other.

I would suggest talking to the histopathologist to discuss the case and establish why this is described as a dermatitis when the skin looks good and you are seeing a mass. If that doesn't yield a sensible plan then don't be shy about asking for another opinion on the histology. Any good pathologist will be happy to chat things through with a colleague, either in-house or after sending the slides to a colleague elsewhere.