click design
right click on row
format field
section "Common"
click on supress

This is what you need?

that is one of the limitation of cross tab,
but in your case you could use select expert
depending on what you need to suppress
put something like
(if  {?@appcentre} ="All" then
table.row_field = table.row_field else
if  {?@appcentre} ="something else"
table.row_field <> "stuff you want to suppress)
into select expert