Can doctor tell before results

Sorry for the long winded post but I’m still confused.

I found a lump in breast and was put on the 2 week pathway which was great.

Was seen very quickly, everyone was lovely, got sent during the same appointment for mammogram, then ultrasound plus placement of markers after 5 core biopsy’s , then back to see the doctor who told me it was cancer and an appointment was made for me to see the consultant/surgeon for this coming Thursday. I’ve managed to access my gp notes where they’ve written to my gp saying M4 and U4 .

so my question is why would the doctor say I have cancer without the biopsy results, could she be wrong.

thanks for reading x