Partially circumscribed mass

Hi everyone-

Short story is, 4 years ago I had a palpable lump, that after testing (diag mammogram, ultrasound, biopsy), it was determined to be a fibroadenoma and was marked with a clip. During that biopsy, the radiologist was wonderful and told me she was 99% certain it was benign and would be shocked if the results came back otherwise. Fast forward to the last few weeks, I went back for an annual mammogram and a new asymmetry was detected in the same breast, but a different spot. I have heterogeneously dense breasts, so I was brought back in for a diag mammogram and ultrasound. This time, the radiologist mentioned it looked like a complex cluster of cysts, but she also saw another solid mass and thought we should biopsy. She didn't give me much information except that she hoped it was similar to last time (fibroadenoma). I went for my biopsy yesterday and the radiologist this time was the Chief of the Dept...very serious, didn't say much. Initially, the thought was they were going to aspirate the cysts and not move ahead with the biopsy (if the previous radiologist was wrong and the solid mass she thought she saw was a cyst and not solid). Right away, he said he wasn't going to waste his time aspirating the cysts and that the solid mass was more suspicious looking than he originally assumed based on the reports. He took three samples and afterwards I asked for his thoughts and he said "It's a solid mass...I will have your results by 3pm tomorrow and we will take it from there".

This morning, my ultrasound and diag mammogram report was posted on the Patient Gateway (online). Overall, based on that report it sounds like another fibroadenoma, but one thing I read made me a bit nervous. The borders of the mass are only "partially circumscribed" (a 12 x 7 x 12 mm partially circumscribed round to slightly oval hypoechoic mass). Of course, I am trying my best not to worry and I will have my results by 3pm today, but I was curious (and please be honest!) if other woman have had partially circumscribed masses that were ultimately diagnosed as malignant? I was given a BIRADS score of 4a, which I know in the grand scheme of things means an 80% chance of it not being cancer. I do have a strong family history of breast cancer and now I feel a little foolish for just assuming it was another fibroadenoma. While I love having access to the test results online, sometimes *too* much information can make things more worrisome. Especially after he said yesterday that the mass was more suspicious than he originally assumed from reading the ultrasound report. Thanks ladies!