Have Cat Questions? Ask a Cat Vet Online.
Yes there are things to do. Ask your vet for a referral to a veterinary oncologist (cancer vet) and they will guide you thru. Radiation is focal and can be done on the skull, if indeed it is cancer. An xray is not diagnostic of cancer with out a form of special scans or biopsy.
Your vet should be able to quickly provide the referral, and give you copies of your records and xrays for the oncologist.
I'm sorry for what you are going through. I also had a pet (dog) that was diagnosed with bone cancer. Feline osteosarcoma is a bit different than canine. I kept the following article when I was researching information for my dog - I've copied the feline info for you to read - and will hopefully guide you and answer your questions. I wish you and your cat all the best.
Feline OsteosarcomaUnlike its canine counterpart it has a much lower rate of metastasis and longer term survival can be expected with complete excision. Median survival for cats with osteosarcoma is approximately 2 years with many cats outreaching that. Due to the slow metastatic rate, radiation therapy can play an important role in osteosarcoma that cannot be totally excised. Though, chemotherapy is not routinely warranted due to the slow metastatic nature of feline osteosarcoma, it should be considered in a case to case basis.ConclusionThere is no other way at this time but to say that the prognosis is poor in pets for long term expectancy although cats fair much better. However, it is important to note that if a majority of the pain is relieved a pet can enjoy a fairly content life until other organs become involved. Therefore, routine examinations should be maintain to monitor how the body is coping and the speed of metastasis. -Dr. N. Lorica
Your vet probably is guessing correctly just based on the lesion he might see...but to know for sure, someone else needs to look at it. Osteosarcoma is a cancer of the bone...but this needs to be diagnosed, because other cancer can spread to the bone.
I do think that treatment and prognosis will be based on the type of cancer if it is diagnosed.