I apologize that no one has responded to your question sooner. Different experts come online at various times. I just came online and saw your question. My name is ***** ***** I’m a biologist with a special interest in cancer in pets. I'm sorry to hear of this problem.
The best case scenario in this situation is that the spot will turn out to be some sort of benign lesion for which nothing needs to be done. The worst case scenario would be that the cancer has spread and it is too late for treatment. In that case, your cat would only have a few weeks. There are many other possible scenarios between best and worst. Cancer in pets usually cannot be cured, but it's progress can be slowed through surgery, chemo, and radiation, just as it can in humans. In animals, however, the nasty side effects humans experience are not common. Most go through chemo with no or few side effects.
If this is cancer, the actual prognosis depends on what is found with further imaging. There are different types of tumors. Well differentiated ones can be removed completely, and after surgery, many cats survive for about two years. Poorly differentiated tumors often cannot be completely removed, and have often spread to other organs, In those cases, survival time is a few months after surgery.
I recommend that you see a veterinary oncologist to give your cat the best chance. Perhaps that is where your vet has already referred you. Lung cancer is not common in cats, so it's not surprising that your vet is not familiar with it. This link will take you to a directory of veterinary oncologists. Click on the 'Pet Owners' section.
As for questions to ask after the ultrasound (if cancer is found):
Has the cancer metastasized? If so, to what organs?
Can surgery remove the tumor?
Will chemo or radiation be helpful?
What is the likely prognosis?
I'm going to give you two websites that will tell you more about lung cancer in cats. This first one is geared toward cat owners:
This second one is geared toward vets, and goes into great detail:
If you have more questions, let me know in a REPLY. I'll be hoping for the best possible outcome for your cat.
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