Joe, I agree that you not tell the patient or family about statistics unless they ask. After all, it is a numbers game and each person is different. If you give statistics when asked, I would preface it with the fact it is just a statistic, an indication of what the "norm" is, but emphasize as you did that it is treatable, and hold out hope.
My wife's onc did not mention prognosis until we asked. Then he told us and we moved on from there. We were impressed with him from the start, because he told us that his first priority was to ease her pain. Then the second was to treat the cancer. He did both with expediency, and has been very supportive ever since.
We were also impressed that he encouraged us to take a trip to Scotland in May, which he knew we were looking forward to, knowing that something had shown up on a PET in December. When we got back from the trip, then he shared his thoughts and asked for another PET. By comparison, there were three new places, and he began chemo. We were grateful that he did not spoil our trip, since it was not urgent to treat and she was feeling very good at the time.
We asked for the prognosis initially because we wanted to get it behind us and move on (besides I would have learned it on the Internet). But I know there are cases where the persons do not want to know, so I would not volunteer it.
Please continue to do the excellent caregiving you are doing with your patients. They are fortunate to have you on their team. And my wife and I are fortunate to have the onc we have. Blessings. Don