Kim,

1. Cavitary masses just means that there may be a "cavity" or pocket.  I'm not sure if they are referring to the actual lung mets, in which case there may be some fluid or blood inside.  The only way to tell this is if a CT or ultrasound is done but it is really an academic point as it won't change treatment.

2. Spondylosis is a common finding on chest rads and means that there is degeneration or arthritis of the vertebrae.  The sternebrae are on the chest (think "sternum" on a person) so right about on the point of his chest he has some spondylosis.  Usually not painful but an incidental finding on older dogs.

3.  There are 2 larger lung mets between the described ribs.

4.  Most of the mets are very small but disseminated (spread throughout all lung lobes).

This is not that bad of a report.  He is feeling fine because his mets are very small, and even the 2 larger ones are not what I would call big.  Follow-up rads should tell you if metronomics or artemisinin are doing anything.  I would wait 2-3 months unless he is having issues.  Jerry's lung met was much bigger on his rads and he did very well on metronomics so even if Buster's mets don't shrink but just stay the same then that would be great. 

Have you seen Dr Clifford at Red Bank?  I pulled his metronomics info off of VIN (Vet Info Network) and noticed that he practices there.  He is very well known and an excellent oncologist so I decided to follow his plan (I just substituted Metacam for Deramaxx because of Tazzie's liver).

Pam and Tazzie