It does not seem to be a fake story. I saw a big report about this case, with the interviews of the doctors who were doing the surgery, and with the guy himslef. There were too much details, including names of the doctors, name of the city and the particular hospital and even X-ray pictures (I am not sure how is it called in a proper way) of his lungs.
This report was shown at the newschannel which is not considered to be "the yellow press".
And the doctors are still not sure, how was this branch of a fir tree able to appear in the lung. So they say that they gonna make some kind of exploration and research about this case, cuz it seems to be unique.
One of the doctors in the TV interview says, that it is impossible for the tree to grow up inside of the lungs, cuz there is no sunlight available. Without sunlight it can't be green pigmentation of the needles. So there are two schools of thought about that...
very strange story indeed!