The full-back was part of the Wigan side that overcame Huddersfield Town at the weekend, with a match against Oldham or Everton separating them from the final four.
"We're coming closer and closer to Wembley now but we'll have to wait and see whether we get Oldham or Everton and then prepare from there," he told the club's official website.
"It is the second time in a row now that we don't know who we are playing yet but it doesn't matter because we have to be ready for anything.
"When the time comes we just have to work hard like we did in the build-up to the fifth round and then who knows how far we could go."
Stam joined Wigan from Twente in 2010.