Hi Lorraine, I had a similar problem to you. I had a small haematoma form following my first mastectomy. This had no tissue expander in at this time, but the haematoma formed and was about a golf ball size. My surgeon let it resolve itself, and it took about 8 weeks. when I had my second mastectomy 9 months later, I had tissues expanders inserted in to both breasts in preparation for implants a few months later. Three weeks after this surgery I developed a much larger haematoma on the newest mastectomy site. This blew up fast and required more surgery to drain the blood away and wash out the expander. They removed 800 mls of old blood, and collected another 200 mls in a drain. This major bleed set me back 3 weeks. This happened 2 1/2 years ago, and everything worked out fine. In fact, this breast is the better of the 2. It is softer and more rounded. This breast also did not have cancer, so the surgeon may have left a bit more fat there for softness. Good luck with it all. These things do happen, and if not too big, will often resolve themselves. Even large ones like mine do not cause issues in the long term. Chris xx