My Mother had a mastectomy (one breast)on Feb. 07 and drainage tube removed after 3 days, so much fluid accumulated that it was removed by needle and then another drainage tube was inserted.  Fluid was so much that it started collecting inside and you could see it building up and infection also developed.  After seeing surgeon another operation had to be done to remove infected area, plus gel-like accumulation and now area is flat, but for my Mom it was like having another mastectomy.
Drainage tube was put in again and kept filling up and she has that little bag attached to squeeze to draw out fluid, but it has now been 4 months and she was sent for a CAT scan to see why so much fluid is coming out.  It showed two seroma's (one is 2" x 3"), but very thin.  Now her surgeon is talking about injecting these sites with tetracycline "so the tissue with stick together".  
First - how/why did she develop seroma's and can they be 'fixed'?
What exactly is the purpose of injecting tetracyline - she and I don't understand what this is supposed to accomplish?  Can this make it worse?  She has been told these fluids usually are absorbed back into the body, but that didn't happen the first time so she is afraid to have the tube out, even though it is hard to sleep properly, go out, etc. with the tube in, but she has had this tube in for over 2 months  - isn't that too long, won't it start breaking down?  P.S. she did not require chemo or radiation.  Any answers you can provide would be appreciated.