Leroy Sievers has spoken about this in his My Cancer blog on NPR frequently - what do you say to someone with life-threatening cancer?
The answer to the question is actually quite simple - something. It doesn't matter how skillful you are, how many right or wrong things you say. What matters is that you say something. What matters is that you talk about both the situation at hand and the other things that we would talk about apart from the situation at hand. What matters is not taking the easy way out, avoiding saying something, avoiding the person, avoiding the obvious.
It's true - there may be some things you might want to avoid, but they are relatively few in number and should be obvious to someone with a modest sense of propriety. You might not want, for instance, to talk about your ingrown toenail as a point of comparison to someone with metastatic colorectal cancer. But talking about your grandmother's struggle with ovarian cancer, or about how the off-season is going with the Toronto Maple Leafs or the Toronto Raptors is definitely fair game.
Having a good laugh is always welcome. A buddy and I, for example, talked today about rules for flirting with younger women ("don't flirt with anyone whose mother is ten years younger than you are").
Another colleague related a story about his father that was perfect for the moment:
"When told that one of the options for his prostate cancer was castration and that he would never have an erection again, the father responded, 'I haven't had an erection since the Olympic Games.' His son turned to him and asked, 'Which Olympics?'"
Definitely, at the right time, humour works.
Shared vulnerability also works, again as the situation and mood dictate. Speaking of comparable situations you have experienced in your own life history demonstrates a sense of "getting it" and indicates a willingness to participate in the emotional landscape of the patient.
What doesn't work is totally inappropriate comparisons and poorly timed seques into your own emotional territory. Again, these aren't hard and fast rules so much as guidelines. A cancer patient doesn't mind at all talking to you about your own life concerns. After all, we care as much about you as about this damned cancer that's eating away at our shared time together. It's the avoidance that's key here. If you want to talk about scraping the bumper on your car, great. But it shouldn't be because the bumper is obviously more important to you than squarely facing the reality of the elephant in the room.
But with that said, the elephant in the room isn't the only reality that matters. What matters is that you're here, you've said something in an attempt to identify with me, you're present in a meaningful way, and that you haven't avoided the obvious. Sometimes, all that matters is the hug, the squeezing of the hand, the attentiveness, the phone call, the email, the prayer.