Because the radiologist thinks it looks OK and you aren't sure how long it has been there, it seems that it would be safe to see what happens over the course of a menstrual cycle.  It could be a lymph node working hard to fight an infection, or it could be something hormonal.  Although cancerous breast lumps are not usually tender to the touch, if it grows over the next month or two, I'd suggest having the doctor take another look.  If it gets bigger and then smaller, it's probably something hormonal.  Make a note on a calendar about exactly where it is and how big it is using a ruler if you can.  Don't check every day.  That will make it harder for you to notice tiny changes.  I hope the lump soon goes away.  

worrywart

10/ 3/09 5:55pm

Thanks