Q: Recently we lost our 13-year-old cat, Cinder. We believe a malignant lung tumor caused a clot that stuck in the artery of one hind leg. It took four days before we could take her to the Oregon State University Vet Training Hospital. By then, the leg tissue had died. A full-body scan showed the tumor and surgery showed that it had spread around the bronchial tube and into lymph nodes. All options were negative. We chose euthanasia, so she would not suffer any more. Making this choice hurt very much.
My first question: How can we diagnose a cat’s tumor earlier, when a cure could succeed? During the last year or two she had sporadic periods of difficulty jumping up on even low heights, but then this condition would clear up and she would make spectacular leaps. Our vet thought the condition might be caused by arthritis, so we treated her for that. A second possible symptom was periodic coughing, occasionally accompanied by attempts to regurgitate. When she did bring something up it was just food, no hair, which seemed odd for a longhaired cat. I suspect we saw the effects of the tumor developing but we did not speak forcefully enough about these symptoms to our vet. So, our comments tended to be brushed aside.
My second question: Would a regular chest X-ray have helped to detect such a tumor? The vet at the training hospital said that an X-ray may not have had sufficient resolution to catch a tumor at an early enough stage to affect a cure.
We have been reading CAT FANCY magazine for many years but do not remember much about lung tumors, how they are detected and how they are treated. I would enjoy reading more on this subject. Maybe that is something for the editor to organize articles about.
I have always appreciated your thoughtful answers to reader questions in Cat Fancy. And, I would appreciate a response to my questions if you have the time.
A: I’m sorry to hear about Cinder. Unfortunately, I don’t think there really is any practical way to diagnose a lung tumor in an early enough stage for there to be any significant improvement in the prognosis. Unlike mammary tumors, which an observant cat owner can detect early by carefully feeling the skin on the cat’s abdomen, lung tumors are unlikely to reveal themselves until they reach a size that causes clinical signs to occur. By that time, it is probably too late.
When it comes to lung tumors, the prognosis depends a lot on whether the cancer is primary or metastatic. Cats with a primary lung tumor, i.e. a single tumor that arises in one lobe of the lung, may be treated successfully if the tumor is detected early and the lung lobe is removed. Cats with tumors that show up in the lungs because a cancer elsewhere in the body has metastasized (spread) to the lungs cannot be treated successfully. I’m not certain whether your cat’s lung condition was primary or metastatic.
I don’t think your cat’s occasional bouts of difficulty jumping had anything to do with the tumor. Your vet was probably correct about this being arthritis, given your cat’s age. Coughing, however, suggests that something might be going on in the lungs. It is possible that the periodic coughing was the first signs of your cat’s illness. Hard to say.
Your vet is correct about regular X-rays. An X-ray cannot detect very small tumors. Tumors need to be of a minimum size (approximately 2 millimeters) before X-rays can show them. Having your cat examined on a regular basis and periodically performing bloodwork is the best way of detecting problems early. I stress these regular check-ups because cats are notorious for hiding their clinical signs until their illness is significantly advanced. Predators pick on the sick ones, and cats are wired to not reveal that they are ill until they can’t pretend anymore. This remains my biggest frustration as a feline practitioner.