How about the following:
RewriteRule ^/page/.*-([0-9]+)\.cfm$ page/page.cfm?PageID=$1
In English, (hopefully) this reads any URL that starts with /page/ then has zero or more of any digit followed by a dash followed by one or more numbers from 0-9 rewrites to page/page.cfm?PageID= followed by the digits captured above. REmember to test using
the testdriver.exe file... I haven't tested this.
You may need to make the .* ungreedy by changing it to .*? (I think), but testing will show you this.
Also, don't forget to add any flags at the end that you may need eg. [I,L] for case Insensitive and Last rule to be processed.