A diagnosis of "probably benign" is not good enough. It is either benign or malignant. You need more information of the change in the breast. I would ask for a copy of the report and see what it says. We can help you in deciphering the terminology. If it is a fibroadenoma, this is benign and does not turn to cancer I believe. If it is calcifications, they do need to be watched. If you have a lump, it needs to be biopsied. If it is a cyst it can be aspirated, but cancerous tumours are solid and need surgery or chemo first if they are large. I am truly shocked that a health care provider can give you such poor information. 4 months is quite a time if you have a tumour - which you may not. Some 80% of breast lumps are benign, so take heart.
Please try and get more information so that you understand what is going on.
Liz.
What did they see that they think is benign? I don't think 4 months is out of line in most cases, but not knowing what they are watching it is hard to say.