I also had a lat dorsi tissue expander put in after mastectomy on the 8th Aug. It's very hard and lots of puffiness under my arm (had lymph sweep 10 days after 2 had c from first op). My plastic surgeon says all is fine, the puffiness is the same amount of 'fat' as on my left side and after chemo/radiotherapy, maybe middle of next year, I can have the op to insert the implant and adjust the other boob (reduction from a 16E probably down to a C/D cup). I have a 550cc expander but have stopped at 400cc. Have had enough of the tightness and swelling. I wasn't expecting it to be so uncomfortable and probably wouldn't have elected to have it done if I had known about the chemo prior. My daughter says it's a good idea as I only need one other op and have been able to use my own skin with no grafting. The scar at the back is really good and not much of a problem. I had to make the decision quite quickly and that has good points and bad ones. A friend had a DIEP flap and has had problems too - it's all traumatic.