I agree with Philipp... Plus, if you've bought ANY sort of general "Travel Insurance" for the trip, there's usually a luggage clause in there to cover some part of a loss. OR, if you've booked using a credit card for all or part of the purchase, usually some "Buyers Protection" can cover losses on the trip.. check with your provider.
9 cruises and counting here, and never lost luggage. I worry more about the airlines losing it!!