My 10-year old male Greyhound had a hard lump under his right eye that my primary vet aspirated and had biopsied. The pathology report indicated multilobular osteosarcoma ;right intraorbital bony mass, low grade. Report said mass composed of spindle cells embedded within a chondromatous or osseous matrix; central areas of calcification often noted; cells exhibit indistinct cell boundaries with a scant cytoplasm and generally monomorphic angular nucleI" mitotic index is 3. THEN, we got a CT scan as recommended by our vet--here's where things get very interesting and where my frustration is mounting. The radiologist showed us the results, mentioned multilobular chondrosarcoma which he said is the same thing as mutilobular osteosarcoma, with a little bit of bone invasion. That day I rec'd a report from a DIFFERENT radiologist who somehow rec'd an online request for evaluation..HIS interpretation basically matched the histological pathology report. THEN the radiologist who actually performed the CT scan wrote up HIS interpreatation the next day, saying it the scan results mistakenly went to the outside radiologist but his findings are "substantially different". He's indicating a fibrosarcoma and says there appears to be lysis and destruction of the underlying cortex but no evidence of periosteal reaction or bony proliferation...says this is most characteristic of a soft tissue tumor invading the underlying bone and it would be very unusual appearance for a multilobular tumor. Now I know from my research the approach to surgery is different and the adjunct therapy could be different also. Finally, the CT report said the patient moved and a repeat of the contrast study would be beneficial..Silly me, I thought we paid those big bucks and had him sedated so they could correctly position him for accurate scan results!...I'm confused and concerned and will not be meeting with the surgergeon until next week. Any input would be greatly appreciated, i.e. is this kind of differing opinion common?; which is more definitive , the CT scan or the histopathology report?; what IS the difference between these 2 tumors?; which is more common in this area of the skull? Many thanks in advance for any response.