Wednesday, July 3, 2013

Three things I learned: lymphoma in cats

Lil' Puss Fawcett, who passed away due to complications of suspected lymphoma. As you can see, life was pretty awesome for Lil.

The Animal Referral Hospital recently hosted an educational information at the Homebush hospital. One of the speakers, oncologist Sandra Nguyen, talked about lymphoma, a malignant transformation of B or T lymphocytes. There are other round cell tumours in companion animals (mast cell tumours, transmissible venereal tumours, histiocytic tumours etc) but in cats lymphoma is the most common. I have a personal vendetta against this affliction as it claimed my gorgeous cat Lil two years ago.

Sandra N is a former classmate of mine and it was great to see her command the floor while everyone took copious notes. I learned a lot, notably that

  • Cats that are FeLV positive are 60 times more likely to develop lymphoma than FeLV negative cats; and cats with both FeLV and FIV are 80 times more likely to develop lymphoma.
  • The talk helped clarify some salient points regarding treatment and prognosis of high and low grade lymphoma. High grade lymphoma is more readily diagnosed via fine needle aspirate and cytology (biopsies are usually required to differential low grade lymphoma from IBD); only 50 per cent of cats with high grade lymphoma respond to treatment with a median survival of 6 months while 98 per cent of cats with low grade lymphoma respond, with a median survival of 704 days. Response to treatment is the most reliable prognostic indicator, but cats with low grade lymphoma may take 2-3 months to show a robust clinical response. In cats, there is no real difference in the prognosis between B and T cell lymphomas. (BTW treatment for low grade lymphoma is often oral medication - people get frightened off by the word "chemotherapy" but are surprised to hear that it can be extremely straightforward and administered at home).
  • Unlike people, who experience a higher rate of side effects associated with chemotherapy, around 30 per cent of cats develop side effects to chemotherapy, only 5% require hospitalisation and death due to chemotherapy complications is likely less than 1%. Cats are less likely to develop sepsis with a low while cell count than dogs.

When detected early, many lymphomas can be treated and managed quite well with excellent quality of life for cats. Of course cancer can be an absolutely unforgiving disease that wins despite our best efforts, but in many cases there is potential to give an affected cat extended quality of life.