It is best to discuss your individual treatment in detail with your doctor. Make a list of questions you may want to ask and don't be afraid to ask your doctor to repeat any answers or explanations you don't understand. You may like to take a close friend or relative to the appointment with you. If you are feeling upset, they may be able to remember details of the consultation which you might have forgotten. You may want them to ask some of the questions you yourself might be hesitant of putting to the doctor.
Some people are afraid of the hospital itself.
It can be a frightening place, especially if you have never been in one before, but talk about your fears with the medical or nursing staff. They should be able to reassure you. You may find the doctors can't answer your questions fully, or that their answers may sound vague. Doctors know from past experience approximately how many people will benefit from a certain treatment, but it is impossible to predict the future for a particular person. Many people find this uncertainty hard to live with and it can cause a lot of tension, but fears are often worse than the reality.