There are several types of biopsies and your Surgeon will no doubt determine the best type for your particular case. Some are done in the Radiology Dept. and a needle is used to withdraw a sample of the area in question. These are done under some type of X-ray guidance. There is also one that is done in Surgery (excisional biopsy) thru a small incision. This is done with both a local anesthesia and IV sedation so you would essentially be asleep. The lump could be removed completely but this will be something for your Surgeon to decide. There is nothing in the report that is different that what you already know ... that you have a lump. The BIRADS IV thing is a rating system used by Radiologists. Scores range from 0 to 5 and each requires a specific follow-up recommendation. A score of 4 always indicates the need for a biopsy. May I suggest that you take someone with you to your appnt. with the Surgeon. We can always use an extra pr. of ears since our minds are usually racing at warp speed and we can easily miss something that is being said. I wouldn't hurt to write down any questions you have and take it with you; don't hesitate to ask even if you think a question might seem foolish .... the only dumb question is the one that goes unanswered. Good Luck & keep us posted.
japdip is right. If no one can go with you for the surgeon consultation, please thinking through and write down all questions you like to ask before you go to appointment.
Please search this Forum, try to read as more as possible, that may answer a lots of questions you may have, also will help you to come out the questions that you may need to ask the surgeon.
Good luck and take care.