Feline lymphoma treatment

Re: Feline lymphoma treatment

listhestar — Sat, 25 Oct 2014 16:52:27 GMT

[quote user="Gerry Polton"]

Best wishes

Gerry

[/quote]

Thanks for the answer. I have used the chlorambucil and pred for a highly aggressive case of multicentric lymphoma in this cat and it has been going now for 8 months. I am giving serious thought to writing it up as case study as I could not find anything. I had full consent trying this and the owner really didn't want CHOP nor could afford it but copes with the costs involved with this protocol. I know this is not a normal thing to try but I can not find anything written up about this protocol for these types of cases. I just wondered if I was floating alone out on a limb trying this?

Thanks guys

Lisa

Re: Feline lymphoma treatment

scatty — Fri, 24 Oct 2014 23:33:39 GMT

Sorry this is not back to the OP but in case anyone wants to see an old thread about LGL and chlorambucil/pred I posted on 18 December 2012 (if you search under my posts). I contacted Gerry at the time and the cat in question is still doing really well in October 2014. Great result for cat and owner concerned!

Cheers,

Anna

Re: Feline lymphoma treatment

Rob Loxley — Fri, 24 Oct 2014 22:48:32 GMT

[quote user="Gerry Polton"]High grade lymphomas are responsive to multiagent chemotherapy and in my hands, the treatment of choice remains COP[/quote]

Going back to the OP, what's your opinion of using chloramb/pred for multicentric lymphoma, if a more involved COP protocol is declined? Worth it or no better than just pred? Or do we just not know?

Re: Feline lymphoma treatment

Gerry Polton — Fri, 24 Oct 2014 15:15:18 GMT

Hi Lisa

This is a good question to bring up. Alimentary lymphoma in cats is most commonly of what we would call a 'large-cell' type. Sometimes pathologists also describe it as 'lymphoblastic'. I would estimate that about 90% of the cases diagnosed in normal practice are of the large cell type. I believe that we will find that, as pathological diagnostics improve, we will find an increasing proportion of 'small cell' types because more cases of cats with chronic gastrointestinal signs will be diagnosed with lymphoma by full thickness bowel biopsy.

The small cell lymphoma of the bowel typically presents with a chronic history of weight loss, intermittent, increasingly frequent vomiting and sometimes diarrhoea, sometimes not. usually there is no palpable mass but sometimes there is. Usually the mesenteric lymph nodes are slightly enlarged and biopsy would reveal reactive changes rather than neoplasia. Sometimes, there are masses, either in the bowel or in the lymph nodes. It is presumed that these masses change slowly but of course we usually only see the cat for the first time 12-18 months after the clinical syndrome really started so we do not have a really good handle on the rate of progress of the lesion(s). These cases are expected to respond really well to treatment with chlorambucil and prednisolone. There are multiple dosing strategies. The range of recommendations seems to go from 2mg chlorambucil every second day to 4mg chlorambucil once every two weeks...PER CAT. Excuse the capitals but it is important to stress that this is not a mg/kg or mg/sqm dose. I prefer the 4mg once every two weeks as a starting point but that does not mean it is right. Prednisolone is given on a range from 5mg every second day to 10mg daily. I usually give it at 5mg daily for a week then once every second day. Again these doses are per cat.

The response to therapy is amazing. There is a paper by Timothy Stein which is free to download in the Journal of the American Animal Hospital Association which is worth a look: JAAHA 2010 Nov-Dec;46(6):413-7. They quoted a 96% response rate and a median remission duration in excess of one year. And that is remission duration, not survival. These cats live a long time. It's a really nice paper actually. It gives a little detail about large cell alimentary lymphomas too.

To go back to the large cell cases. These are high grade cancers that progress quickly. High grade lymphomas are responsive to multiagent chemotherapy and in my hands, the treatment of choice remains COP. There are oncologists and regular practitioners who feel that a doxorubicin-containing protocol is superior but I still have yet to see the evidence that this is truly the case.

Best wishes

Gerry

Re: Feline lymphoma treatment

Martin Atkinson — Thu, 23 Oct 2014 17:35:32 GMT

I do not wish to steal Gerry's thunder (well obviously I do) but I asked him about a case of alimentary lymphoma and he suggested that chlorambucil was not the best choice and advised me to use straightforward COP. The cat in question had an enterectomy but there was advanced spread into the mesenteric lymph nodes. It did very well for over 9 months until it developed a hepatic mass and became quite ill again and was PTS. We did not investigate if this was lymphoma or something else.

I'm sure Gerry will be along soon to correct or possibly agree with me.