I am a Chinese physician, currently serving as a chair in the internal medicine department. I believe the author's experiences, but the interpretation of them are false:
In the first case, the US doctor is not professional. First of all, his anwser was wrong; if he is not an oncologist, he should not pretend he knew the answer. Second, he should not give suggestions for a patient he knew nothing about. The moment he answered your questions, a patient-physician realtionship was established. He can be sued in the court of law for his consult of this patient if a bad outcome ocurred after follwoing his recommendations, as his suggestion was learly false. The Chinese physician was right not answer you questions as he knew nothing about your patient.
In the second case, it is rare but acceptable if you make an appointment to see a specialist without pateint present. He can review your clinical data and give a suggestion. Remember, he is still legally liable to do that. It is another matter if he is your personal friend.
In the third case, you were probably seeing a family doctor or an internal medicien doctor. He did not know what to do in this situation. The best action is refer you back to your oncologist. The physician should better explain the situation to you.
From my experience, foreign physicians are ususally better clinically, but not as well in communication skills. If you do have a problem you need to see a doctor, the doctor in the same ethinic background is still your best bet.