How would you assess an elderly cat for neoplasia such as lymphoma?

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

HMC — Thu, 10 Feb 2011 15:38:35 GMT

What treatments did you end up giving?

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Bob Russell — Thu, 10 Feb 2011 14:33:37 GMT

Latest update - cat is doing well, has put on weight. However wbc count still 34.2 but Lymphocytes predominate (in house machine) 17x109/l (N: 1.5-9).

Ionised Ca 1.28 N.

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Rob Loxley — Fri, 04 Feb 2011 19:59:53 GMT

[quote user="Kate Richardson"]However, we still get some pH errors even if blood spun and separated immediately after collection, so anyone got any magic tricks?[/quote]

We follow CSLS's instructions: http://thehormonelab.com/handbook/calcium-disorders/parathyroid-hormone-pth-and-ionized-calcium-ica

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Bob Russell — Fri, 04 Feb 2011 13:24:04 GMT

Cat is not polyd. It is remarkably well in itself!

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Kate Richardson — Fri, 04 Feb 2011 12:58:53 GMT

We were advised by our lab (TDDS) to send heparinised plasma and to exclude as much air as possible from the tube. Usually means taking 4-5mls of whole blood to get enough plasma to fill a plain tube. However, we still get some pH errors even if blood spun and separated immediately after collection, so anyone got any magic tricks?

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Anonymous — Fri, 04 Feb 2011 12:05:11 GMT

[quote user="Laurence Webb"]

How do peope assess renal function in non-azotaemic cats with hypercalcaemia and dilute urine? I often feel it's a bit of a conundrum if you can't do other investigations for financial reasons.

Does a cat have CRF leading to 2ary hyperparathyroidism or are they PD because of the hypercalcaemia caused by neoplasia etc?

[/quote]

If non-azotaemic with hypercalcaemia and dilute urine, I'd assume that the kidneys were structurally fine. A harder one is where the cat is azotaemic with hypercalcaemia and inappropriate lack of concentration of urine. Here I'd do an ionised calcium which I gather is normally within the reference interval if the elevated total calcium is due to secondary renal hyperparathyroidism, whereas will normally be above the upper reference limit if this is'genuine' hypercalcaemia. (Also interpret with respect to phosphorous levels)

On the subject of ionised calcium... had a cat this week presenting with 3 days anorexia and lethargy and hadn't been seen drinking for 3 days. Owner not keen on much by way of investigation, but in-house blood sample showed hypocalcaemia - my main differential was 'analytical error', but repeated on same serum sample and got similar result (obviously doesn't rule-out contamination of serum tube with EDTA etc, but I took the sample myself and was fairly confident I'd not messed up collection etc.). In current job, don't have access to point-of-care analyser (iStat / epoc etc) that tests ionised calcium, so was hoping to post a sample away for this to confirm 'genuine' hypocalcaemia. The owner declined, but it brought up the question as to where to send a sample to? The large multi-service lab we normally use provides an 'estimated iCa at pH 7.4' (with a 2 day turnaround) on receipt of 'Fill[ed] plain tube with whole blood or serum to exclude air'. I remember that a different lab I'd contacted before (http://www.ctdslab.co.uk/ionised%20calcium.html) had advised that the exclusion of air in the tube wasn't necessary for their test as they had an assay which corrected for the change in pH that inevitably occurs during transit. Anyone any suggestions what the best way of measuring an ionised calcium is if not able to do in-house?

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Laurence Webb — Fri, 04 Feb 2011 11:27:51 GMT

How do peope assess renal function in non-azotaemic cats with hypercalcaemia and dilute urine? I often feel it's a bit of a conundrum if you can't do other investigations for financial reasons.

Does a cat have CRF leading to 2ary hyperparathyroidism or are they PD because of the hypercalcaemia caused by neoplasia etc?

[quote user="Mark Hedberg"]

Take a urine sample, and heat it up to boiling, then let it cool down. (Test tube and bunsen burner.) If you see a fine smoky (it's like cigarette smoke) haze in the urine, that's Bence-Jones protein. Bence-Jones protein is produced by malignant tumors and excreted in urine. If you want to double check, reference labs can also test for Bence-Jones.

Anyway, if it's positive, your cat has a malignant neoplasia.

[/quote]I've never heard this before. Very interesting

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

jd2008 — Thu, 03 Feb 2011 23:30:16 GMT

Check urine for presence of bacteria. Have seen a lot of low grade UTI's cause weight loss in elderly cats. Can do this during a consult if you have centrifuge, microscope and Diff Quick to hand.

As others have suggested, run ionised calcium.

Check systolic blood pressure with doppler.

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Christopher Saul — Thu, 03 Feb 2011 23:02:25 GMT

It's a shame that financial constraints mean you can't work this cat up , it's always frustrating in these circumstances. In general terms, first step is to do an ionised calcium to establish if this is 'real'.

The main thing is I'd echo the thoughts of everyone else that this cat does give you that 'cancer' feeling - the normal renal parameters makes renal secondary hyperparathyroidism very unlikely. Here are one or two other musings....

Remember, though fairly uncommon, cats can get 'idiopathic hypercalcaemia' - where there is no identifiable cause - treatment is steroids in the first instance, bisphosphanates if this fails. Otherwise differential list is similar to that in dogs........

Hypercalcaemia of malignancy, primary hyperparathyroidism, idiopathic hypercalcaemia are the first things that spring to mind.

A few less common differentials: Addison's ( rare in cats but has been described; maybe do a basal cortisol?) Hypervitaminosis D ( do the owners have any vitamin D containing medications or skin creams that the cat could be getting hold of?) ). Granulomatous diseases eg FIP? Nutritonal secondary hyperparathyroidism

Next step, I'd say imaging. If no obvious cause then I'd run a PTH and PTHrp at cambridge specialist labs.

I guess however if you really do have your hands tied then steroids may be the way forward, though I'd be sure to let the owners know that this approach is not ideal and getting a diagnoisis is preferable..

Good luck

Chris

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Richard Fox — Thu, 03 Feb 2011 19:38:28 GMT

I am afraid I say this to a lot of my clients were money or owner compliance is difficult to obtain - Your hands are a bit tied - if you have none then you can't work up the case properly and thus the owner has to accept really limited info and probably rely on clinical observation and response to symptomatic treatment?

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Bob Russell — Thu, 03 Feb 2011 17:49:57 GMT

Have spoken to owners. No magic answers. They are not going to go down the imaging route but I have suggested we test for the main things we can treat ie the assumed non-neoplastic conditions, pancreatitis/urine sample for renal probs. Cat is going onto sensitivity control food for now and if all fails we may try good old steroids!!

May be I am having a duff week but I can usually put together a reasonable investigation protocol. Struggling to know where to go with this one without spending money!

Once again thanks for the input. Clearly there is no way forward with this one without spending money and it is well so euthanasia not appropriate yet!

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Bob Russell — Thu, 03 Feb 2011 17:17:35 GMT

Haematology was done in house but checked this morning (same sample) by external lab - results not the same numerically but still same high wbc, neutrophilia, eosinophilia, monocytosis.

Teeth not particularly poor. T4 39 (N 19-62).

Comments appreciated!! Thank you

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Mark Hedberg — Thu, 03 Feb 2011 17:08:47 GMT

Anyway, if it's positive, your cat has a malignant neoplasia.

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Kate Richardson — Thu, 03 Feb 2011 16:50:05 GMT

Gut feelings may not be scientific, but I use it a lot too!

I would repeat a calcium (+ ionised Ca if finances allow) to see if persistently hypercalcaemic.

Definitely urine analysis to assess for renal insufficiency, many cats will have low sg before any azotaemia. Assume she has no dental disease? I've seen a number of cats with what the owners describe as polyphagia, always asking for food, which have turned out to be due to dental disease- they ask for food often but actually eat less in total, due to pain, leading to weight loss.

Was the haematology done in house or externally, I'm always wary of in house results, so any in house abnorms detected I get verified, as have had machine saying marked lymphocytosis and external lab (on same sample) saying normal, and vice versa! Was there a left shift or any suggestions of neuts looking toxic to suggest infection vs inflammation?

What was the T4- if it was robust, then cat could still be hyperthyroid but has an infection or something else causing suppression of a high T4 to within normal range.

Then I would definitely be thinking of GIT disease- intestinal lymphoma and IBD can cause polyphagia and absence of biochem changes with weight loss always makes me think GIT. Including pancreatitis so a PLI would be good. But I would probably be reaching for the ultrasound to assess abdomen further. Chest xrays as suggested to assess for neoplasia or any other changes to account for the neutrophilia.

Don't rule out liver disease either, if liver is knackered (not very scientific either) then there may be little normal tissue left to release enzymes, again ultrasound would tell you more.

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Richard Fox — Thu, 03 Feb 2011 16:10:47 GMT

Maybe rule out other things - i.e.:

1. Chronic pancreatitis - and hx of V+?

2. Any diarrhoea that might suggest an enteric problem?

3. Urine dipstix & TP/SG?

4. US of abdomen +/- chest rads - survey?

5. Ionised Ca2+ ?

I favour a crystal ball myself ;)

Re: How would you assess an elderly cat for neoplasia such as lymphoma?

Mark Holmes — Thu, 03 Feb 2011 16:08:04 GMT

I understand that mediasteinal lymphoma is more likely to affect Ca levels than lymphoma elsewhere (at least in dogs) so I would take chest xrays. Plus you can palpate an abdomen in a thin cat with as much or probably more sensitivity than radiography so if you cannot feel it its probably not there.