What Causes Pain And Swelling In Breast?

Good morning, I am a cancer patient who had mastectomy of one breast. I had chemotherapy but couldn't manage to endure more than four treatments then resorted to alterntive treatment. Over the past week I have had pain and swelling in the other breast and was given Augmentin 625mg to rule out the possibility of an abscess being the cause. I had also a mammogram and ultrasound done yesterday and was told that it was due to inflammation and I am curious about this, because I had similar problems but more severe before I had done the mastectomy. I wonder whether this could be the first step toward a cancerous growth again. I am awaiting the results from my doctor whom I will most likely hear from next week. I would appreciate your kind opinion if it is possible. Thanks in advance for your kind reply. Gloria Banarsee