13 year old daughter with breast indent

hi everyone. Looking for some advice. My 13 year old daughter has an indent in her breast. She is very well grown for her age currently a 40f bra size!!

I have took her to the doctors who referred her to the breast clinic on a 2ww. She is being Friday!!

What my question is: can it be breast cancer with just an indent? I have felt no lump when pushing on it although I don't really know what I'm looking for.

I am so scared for my daughter not only is she so young she's also autistic and suffers greatly with anxiety.

Thanks in advance for any reply xx