Had breast mri and there is a white spot. what could it be?

Different things: Usually they inject a contrast for breast mri. The contrast goes thru your circulation. A white spot could be a blood vessel, an area of inflammation, a benign or a malignant tumor growth. An expert radiologist can differentiate the finding. Please ask your physician for a full report which was issued by the reading radiologist.

There is: not enough info to answer the question, because signal intensity varies depending on what particular MRI sequence is being performed, and whether or not IV contrast is used. For example, a benign breast cyst is hyperintense(white) on a T2-weighted sequence, and hypointense(dark) on a T1-weighted sequence. A benign fibroadenoma may be dark on T1 without contrast, but white with contrast.