The black box warning for Forteo has been lifted. I believe it first came out in 2002 and there has not been a single case. Tymlos is newer: that is probably the only reason the black box hasn't been lifted for that. As a person who had breast cancer, I do worry about small bone metastases growing but fractures are painful and disabling so it is well worth the risk in my view. But the osteosarcoma concern has proven to be unfounded.

I take Forteo. I have normal bone density but have broken numerous bones (in the 14, 15 range) with some rare fractures so I meet the Osteoporosis diagnosis criteria.
I saw the notes about the lab testing but also knew most of it was high doses. What makes me more comfortable is that it's been around for about 20 years and the medical professionals keep extending the number of years you can be treated with it.