cat breathing

Question
I took in a stray cat 1 1/2 years ago.  My vet estimates her age at 8, although she is taking medication for an over active thyroid and a different vet (who did not see the cat) said that she must be older to have that condition.  She had a lump growing at the base of her spine above her tail which we surgically removed.  It was not biopsied.  One or more lumps are slowly growing back, which my vet said may be vaccinne-related sarcoma, very serious, for which nothing can be done.  The cat is perfectly comfortable, never scratches or reaches for the lump.  For now, we're not dealing with it.  She cannot jump with her hind legs.  She can pull herself up, and we placed piles of things near beds and a sofa that she likes to be on so she climb/pull herself up.  We assume she had an injury to her legs, hip or somewhere, but she's in no distress.  She's a sweet, friendly cat.
The question is:  since we have had her, she has breathed in an exaggerated, heaving way, her entire chest/belly inflating and deflating, especially below her midsection/waist.  The vets have seen this, but have no idea what it means.  Can you comment on her breathing (or anything else)?  Thank you.

Answer
HI Beatrice,
  you can ask the vet. to do a chest x-ray, because I have seen cats who have fluid in the chest with causes them to breath heavy. In this case if there is fluid on the chest the vet. can do a "chest tap" where they can drain some of the fluid of the chest helping her to breath better. It is temporary however, i'm sad to say. The fluid that they drain can be sent to a lab for diagnosis. Sometimes it can be cancerous. Sorry that I don't have been news. See if you can take her to the vet. tomorrow for the x-ray. Keep me posted. Good luck.

p.s
Sometimes the heavy breathing can be from feline asthma aswell, the vet. can and will look at the lungs along with the chest on an x-ray.