louisewalters, sometime patients are offered antiresorptive osteoporosis medications to prevent bone metastasis after breast cancer. Your oncologist may want to prescribe zoledronate (Zometa) or denosumab (Prolia) which would protect against bone loss and metastasis. You might look at side effects of each before your appointment.
Chemotherapy and radiation cause bone loss. The fifth to seventh ribs are directly behind the breast in direct line of the radiation. Letrozole also causes bone loss by reducing hormones that can contribute to recurrence.
Some oncologist are using teriparatide, with caution. It restores bone and cartilage. It formerly carried a black box for risk of cancer of the bone, but that has been removed. You might look at this article to see if you would even be willing to take it https://pubmed.ncbi.nlm.nih.gov/40578986/. Your oncologist is likely to be reluctant to prescribe teriparatide.
It's impressive that at 64 your bones had no abnormality anywhere in the skeleton.
I hope you are recovering well and that your appointment is helpful.