Hi and welcome to HCM,thank you for your query.
You probbaly meand that it can be fibroadenoma
or other cysts and benign lesions but you should not take that risk and you need to at least mamogaphy and ultrasound
to rule out maligancies since this is not somehting that should be ignored. Most common this is not cancer but you should confirm this by these diagnostic tests.
Wish you good health. Regards