Yet another of my pets ill!

Re: Yet another of my pets ill!

Andrew Kent — Sun, 21 Apr 2013 10:41:57 GMT

[quote user="robloxley"]

[quote user="Andrew Kent"]FNA isn't much use in mediastinal masses unless you have flow cytometry performed as thymomas and lymphomas often look very similar.[/quote]

How about PARR? Also how accurate is signalment at predicting lymphoma vs. thymoma?

[quote user="Andrew Kent"]if you don't want to investigate then lymphoma is really the only treatable option[/quote]

I thought the prognosis after thymoma removal was pretty good?

[/quote] Sorry that should have said only medically treatable option - some thymoma's can do well following surgical removal but that was unlikely to be considered in this case.

Im not aware that anybody has demonstrated PARR to be useful, I would guess that may be because we don't have the relevant markers yet. But Flow has been and is much more accessible in this country with lots of centres running it. Though histopathology and immunohisto is still the gold standard option.

there is a big overlap of Signalment between the two.

Andy

Re: Yet another of my pets ill!

Rob Loxley — Sun, 21 Apr 2013 00:35:52 GMT

[quote user="Andrew Kent"]FNA isn't much use in mediastinal masses unless you have flow cytometry performed as thymomas and lymphomas often look very similar.[/quote]

How about PARR? Also how accurate is signalment at predicting lymphoma vs. thymoma?

[quote user="Andrew Kent"]if you don't want to investigate then lymphoma is really the only treatable option[/quote]

I thought the prognosis after thymoma removal was pretty good?

Re: Yet another of my pets ill!

Hanna Bennett — Sat, 20 Apr 2013 21:12:27 GMT

no specialist status to claim but i'm with Andrew as a result of a referral a few years ago when i had an older cat which was referred and we were recommended trial vinc/pred on the basis of if it shrinks it is lymphoma, if it doesn't it is thymoma - seen enough lymphomas in older felv - ve cats to avoid ruling it out without trial therapy IF the cat is suitable - if not then Bob you made the right decision - sorry but hope your three are now up.

Re: Yet another of my pets ill!

Andrew Kent — Fri, 19 Apr 2013 19:13:39 GMT

[quote user="David Mills"]

[quote user="Andrew Kent"]There are differentiating features but these are often not evident, often they just have benign looking lymphocytes in both. If I remember correctly a retrospective on this found it was only useful in about 35-40% of cases so I don't think you can make any real decisions based on cytology alone.[/quote]

How many numbers in this retrospective? I think there's a real danger drawing strong conclusions from these types of studies, especially if you haven't much experience of the procedure (I've no idea if you have or not), but my experience (~70 mediastinal lymphomas) is that if its a newly-diagnosed lymphoma, it will be obvious on cytology. The problem comes in diagnosing thymoma accurately. In this case, an aged cat, the odds are heavily stacked on lymphoma - unless this retrospective was cohorted for age then it remains pretty weak, experimental data. EBM must include a recognition that most studies and texts extrapolate to the 'average cat' thence back to the individual in front of you. In retrospectives with multiple clinicians and a non-controlled population the logic of this extrapolation is somewhat weak.

[/quote] Well then clearly you should publish your experiences rather than just bringing them up on a forum as it goes against the published data. Otherwise as you say it is not open to scrutiny. Even on histopathology these things are difficult to tell apart without immuno.

the problem is that the treatment of these possibilities are completely different and so unless you can be near enough 100% sure on cytology it isnt helpful, and in fact there is a reasonable likelihood you will be making a misdiagnosis if you rely on cytology. thymocytes and lymphocytes look identical on cytology so I struggle to see how you can be that confident in your diagnosis on cytology alone.

but as i say please do publish your experiences so that it has some validity. With all due respect I work with a number of specialist clinical pathologists and they are the first to admit that they cannot reliably differentiate these two.

Andy

Re: Yet another of my pets ill!

David Mills — Fri, 19 Apr 2013 15:41:48 GMT

Re: Yet another of my pets ill!

Bob Russell — Fri, 19 Apr 2013 13:49:38 GMT

Thanks for the opinions - I did consider them all carefully!

Re: Yet another of my pets ill!

Andrew Kent — Fri, 19 Apr 2013 12:25:54 GMT

[quote user="Bob Russell"]

[quote user="Michael Woodhouse"]

[quote user="Andrew Kent"]why not give some vincristine and pred and see if it shrinks? [/quote]

Sounds like already PTS

[/quote]

Yes - by family agreement.

Reliably getting preds in would have been difficult if he was well enough to return to his old lifestyle.

[/quote] Sorry to hear that Bob, cats are tricky from this respect!

Re: Yet another of my pets ill!

Andrew Kent — Fri, 19 Apr 2013 12:24:55 GMT

[quote user="David Mills"]

[quote user="Andrew Kent"]FNA isn't much use in mediastinal masses unless you have flow cytometry performed as thymomas and lymphomas often look very similar.

[/quote]

Beg to differ. There are a number of distinguishing features (mast cells, size and uniformity of lymphocyte population(s)), though it takes a little looking, and experience. All doable in practice, with Diff-Quik.

[/quote] There are differentiating features but these are often not evident, often they just have benign looking lymphocytes in both. If I remember correctly a retrospective on this found it was only useful in about 35-40% of cases so I don't think you can make any real decisions based on cytology alone.

Re: Yet another of my pets ill!

Bob Russell — Fri, 19 Apr 2013 11:30:50 GMT

[quote user="Michael Woodhouse"]

[quote user="Andrew Kent"]why not give some vincristine and pred and see if it shrinks? [/quote]

Sounds like already PTS

[/quote]

Yes - by family agreement.

Reliably getting preds in would have been difficult if he was well enough to return to his old lifestyle.

Re: Yet another of my pets ill!

Michael Woodhouse — Fri, 19 Apr 2013 00:45:41 GMT

[quote user="Andrew Kent"]why not give some vincristine and pred and see if it shrinks? [/quote]

Sounds like already PTS

Re: Yet another of my pets ill!

David Mills — Thu, 18 Apr 2013 22:35:05 GMT

[quote user="Andrew Kent"]FNA isn't much use in mediastinal masses unless you have flow cytometry performed as thymomas and lymphomas often look very similar.

[/quote]

Re: Yet another of my pets ill!

Andrew Kent — Thu, 18 Apr 2013 20:16:48 GMT

FNA isn't much use in mediastinal masses unless you have flow cytometry performed as thymomas and lymphomas often look very similar.

if you don't want to investigate then lymphoma is really the only treatable option so why not give some vincristine and pred and see if it shrinks?

Andy

Re: Yet another of my pets ill!

Anne Seawright — Thu, 18 Apr 2013 18:22:15 GMT

So sorry Bob. It's so difficult when it is your own pets. Hope all the bad luck is over.

Re: Yet another of my pets ill!

Bob Russell — Thu, 18 Apr 2013 15:56:21 GMT

My sons came over to see him (one has travelled back from Masstricht to see the staffie!) and it was decided that we would not go for chemo!

Family decision to call a halt so we did!

Pretty crap year really but hopefully that is the third thing of three!

Re: Yet another of my pets ill!

David Mills — Thu, 18 Apr 2013 13:43:03 GMT

Ah, I see now on the DV.

Yes, seconded above - FNA of the mass with US guidance will give you a diagnosis. Or you could spin the bloody effusion down and look at slides of the supernatant.

In a 12yo cat lymphoma is highly likely. Any idea about FIV/FeLV status? Only because success/failure of chemo can be severely affected by that. Preds + chlorambucil would be my cocktail in a free roaming cat. I would drain as much of the effusion first as this will improve any dyspnoea markedly (and frusemide won't shift it if its proteinaceous/bloody).

Tough case, best of luck.

Re: Yet another of my pets ill!

Rob Loxley — Thu, 18 Apr 2013 12:55:38 GMT

[quote user="Bob Russell"]I am not going to do a lot of investigation but wonder if treating as lymphoma/?thymoma may be worth a go. The alternative is clearly euthanasia and this is the plan at present.[/quote]

FNA can be helpful. Likewise if the alternative is PTS then I'd maybe try some preds.

Re: Yet another of my pets ill!

Mark Hedberg — Thu, 18 Apr 2013 12:50:02 GMT

Ow, sorry to hear that! Not great.

Re: Yet another of my pets ill!

Bob Russell — Thu, 18 Apr 2013 12:38:54 GMT

Drained blood only. X-rays have been looked at by diploma holder so pretty sure there is a mass present.

Re: Yet another of my pets ill!

Mark Hedberg — Thu, 18 Apr 2013 12:25:28 GMT

Get the fluid out (drain, frusemide never mind, it's blood) and see what the chest looks like on rads - don't panic, i know after all your trouble that we jump for the worst, but I don't see a dramatic mass either (well, with all that fluid, it probably wouldn't show anyway.) Fingers crossed!

Re: Yet another of my pets ill!

David Mills — Thu, 18 Apr 2013 12:08:13 GMT

Have you drained any of the effusion?

A cheap, low stress protocol:

Drain some effusion. Look at s.g., TP, and cytology of the sediment from a spun sample.

Put an ultrasound probe on and look at left atrial size.

Top differentials are CHF, neoplasia and pyothorax, all of which are (normally) differentiable by thoracocentesis, repeat rads, fluid assessment and echo - all doable cheaply and in practice.

Although tumours would be high on the list, I can't see an obvious one on this rad - just effusion.