SCC + chronic rhinitis differential diagnosis

Male neutered cat 10 year old. years of sneezing with serous
discharge.
nasal swabs are negative for calci, herpes and chlamydia

Biopsy punch of tumor on nose of about 6 months duration : scc either
prestage or stage I

Vet is unsure whether xrays of head which show "calcification"
indicate a neoplastic process

Small free floating 1 mm nodule was found in back quarters

What indications on skull image films are indicative of cancer of the
nasal passages? What should I look for in the pathologist report to
determine the extent and rate of growth of the cancer?

How to most economically determine if cancer has spread to nasal
passages. what is the average length of life of a cat with a scc nasal
tumor that seems to be slowly evolving?

Any vets out there to help? Thank you.