I believe in the "need to know" philosophy and respond with "So far so good" or adding "One day at a time is a pretty good pace and thanks for asking." In other words, if there is not a real "need to know" about my condition I keep it simple. For close friends or others going through similar cancers I am more detailed. "Hey, how about coffee and we can talk." This can lead to deeper, meaningful conversations for both of us. Sharing the good and not so good is a healthy stance benefiting myself and hopefully the other person in similar straits.