I understand your concern. I have had a similar experience. I am scheduled for excisional biopsy next week. I have a 6cm fibroademoma in my right breast. I have had all of the tests (including core needle biopsy) and the results of that were fibrodenoma with atypical cells. When you have a large tumor, even after needle biopsy, they often want to remove the whole thing to completely rule out cancer.(very rare in fibroadenomas) I met with my surgeon yesterday and she told me that I needed an excisional biopsy. This procedure will be done as a day surgery,no drains, disolvable sutures and just a few days off of work (I am a hairstylist, so I have a physical job). She said that often, people are back to work the next day. She also told me that it is not considered a lumpectomy unless you have cancer. I would definitely recommmend needle biopsy (it is not that bad) to know exactly what you are dealing with. Good luck to you.
Did you have a needle biopsy to determine that it is a fibroadenoma? Usually these are followed (once determined by biopsy) with mammograms and/or ultrasound. 2.4 cm is not huge - it is just about an inch around. If you are having a lumpectomy there is usually not an overnight stay or drains put in. A lumpectomy for an already biopsied benign fibroadenoma is usually less complicated than a lumpectomy for a cancerous lesion.