At the current moment, I do not believe so. I was selling off all those random airdrops that I couldn't find any information on and had to type in each pair individually. But I think future versions of DEX will include a list format of all your open orders from some screen images I have seen. (I think the picture was on the Waves wiki). Will be nice if that does happen because it's somewhat time-consuming looking up each pair to cancel or make changes.