You must be SO frustrated by the lack of a definitive diagnosis! I can't believe that modern technology isn't advanced enough to find what the primary cancer is in some cases. I may have mentioned that my best friend lost her dear father (56 yrs old) last year (on Father's Day, no less) to a "cancer of unknown primary origin." After my mother's experience, I've become convinced that her father had cc, and she has too. It was mainly in his liver and bones and he was given some chemo and radiation before he decided he'd had enough - he died 3 months later. It just makes a horrible situation even more difficult when you don't even KNOW what entity you're dealing with.
So, is your father thinking of doing the chemo? I thought he had refused any kind of treatment, but I may be remembering wrong. I'm not going to tell you that you should or shouldn't advise him to do chemo, as that is a very personal decision and I wouldn't want to steer you wrong. My mother tried the Gemzar/Xeloda combo and it was very debilitating for her, but I think she was too far along and she already had a compromised immune system so her case was a bit different. I know he must be tired of all the doctor visits, but have you considered a second opinion? IN some cases you can send the medical records to another oncologist and you don't even have to see them in person, so it would spare your father the exhausting trip.
So so sorry you're not getting any answers or support! My stepfather had lung cancer and I would think it would be a very obvious diagnosis - it usually affects the lungs pretty completely before it metastizes, so I'm also skeptical of the diagnosis if he doesn't have any difficulty breathing or xrays show no lung involvement. THen again, maybe lung cancer can manifest itself differently than it did in my stepfather's case. And how can they know what kind of chemo to recommend if they don't know the primary origin? I'm just at a loss as to what to tell you, but I feel your frustration and impatience.
I hope someone can give you some better guidance than I have - I'm following your dad's story with caring and concern and I hope they're able to do something for him. Did they at least give him some nausea meds or pain meds?
By the way, those are lovely poems you posted and I have to ask if you wrote them yourself - if not, do you know who wrote them? They're beautiful!
Thinking of you and wishing for the best,