The actor was speaking at a Q&A session in Milton Keynes with fellow former Doctors Colin Baker, Peter Davison, Paul McGann and Sylvester McCoy, where he said he would "consider" a possible return.
"Well, if they ask me nicely or I could see what they wanted me to do I would consider it because I think the fans have been so good to me, they expect me at least to make an appearance so of course I would consider that," he said.
"If it was something witty but I would want to know what the detail of the scene was or what I was supposed to do. I just don't want to be paraded through as some shagged-out old icon of the last century. It's too much of a source of happiness."
Baker also revealed that the role ended up "killing" his career as a serious actor, saying: "I was never really happy until I became Doctor Who.
"At the same time, although it's the loveliest job I ever had, it essentially killed my career stone dead because I suddenly realised I liked being Doctor Who more than anything that had ever happened to me. So when I went to play Macbeth the audience wanted me to play Macbeth in the style of Doctor Who and naturally I did.
"Afterwards a critic said, 'I had no idea how nice Macbeth was'. So I realised then that the people coming to see me - people like you - didn't want to see me playing Jack the Ripper or whatever it was.
"So when I went to Ireland to play Sherlock Holmes and Moriarty in the same play, they were absolutely baffled because they were absolutely interchangeable, my reason being the same person, really. So that was another failure, a glorious failure."
Steven Moffat said earlier this year that the show's 50th anniversary in 2013 will be amazing for the fans.
Doctor Who will return to BBC One in the autumn.
