Hi Naomi,
Sorry to say Welcome to the club :-)
The other ladies have given you some great advice about obtaining further information. One week ago I had a mastectomy with sentinel node biopsy and immediate reconstruction, so while I can't tell you about a lumpectomy I can tell you about the sentinel node biopsy procedure. The dye injection was done the day before surgery. You will have a radioactive dye injected into the areola (mine was two injections both around 55ml) stings a little bit but I didn't find it anywhere as bad as the core biopsies) then you get checked after a short time to see how far the dye has travelled towards the sentinel node (it looks pretty impressive on the screen) if the dye is not moving fast enough you will be asked to massage your breast to help speed it along and then you have the ct scans done which in effect pinpoint where the sentinel node is for the surgeon. They pinpoint not only where it is from the nipple but how deep it is, etc etc 3d pinpointing for exact location. Then I was coloured in with a texta to show location on skin. Given report and scans which of course I promptly opened to check it all out ;-) saw a fantastic picture of my own skeleton with my arms above my head that looked as if I was yelling out WOOHOOOOOO!!!!!! All in all it took about 2 hours (had been told it could take anything up to 4). And that was my part in the sentinel node biopsy.Had been told I would turn blue so had the camera ready to take a picture of my impression if being a smurf but I didn't even turn grey. During your lumpectomy you will have more dye injected again and that will stain parts of your breast blue (so don't be scared when you see it it's OK) the surgeon will use a machine like Geiger counter to track the radioactivity and confirm the sentinel node and then remove it for biopsy! How wonderful to have this technology so when it comes time to have it removed there is an accurate destination for the surgeon. Your bodily functions will leave your body as a brilliant green colour for a couple of days and again nothing to worry about. Hope this helps a bit. What day is your surgery? I'm sure we will all be thinking of you and wishing you the best. Take care Xx Cath