problem get the value of /usr/ucb/ps -guxww

Hello all
im trying to get the value of:

/usr/ucb/ps -guxww | grep Tomcat | grep $USER | grep -v grep

into variable , im using csh .
like this :

set PS="/usr/ucb/ps -guxww"
set isTomcat = `cat $PS | grep Tomcat | grep $USER | grep -v grep`

but im keep geting this error:

cat: cannot open -guxww

how can i get the output right ?
thanks

Get rid of the cat.

set PS="/usr/ucb/ps -guxww"
set isTomcat = `$PS | grep Tomcat | grep $USER | grep -v grep`  

but now if i do :
echo $isTomcat im getting the error:

set: No match

why ? how can i echo the value ?

Your code actually works for me when I try it...
Obvious question: Is the $USER variable set correctly?

yes it does