How bad is bone cancer osteogenic sarcoma?

Extremely: Most osteosarcomas / osteogenic sarcomas are aggressive. Once almost uniformly fatal, today we are curing many of these hated and all-too-common cancers, especially in younger folks. One of the men who taught me surgery was one of the first survivors; he had only half a jaw but did great and used to laugh about it. I wish you / your loved one the very best.

Treatable: Not too long ago osteogenic sarcoma used to be almost uniformly fatal. But with chemotherapy regimens now available, the majority of patients can be cured. Surgery is also required and in most cases the tumor can be removed while keeping the limb. While it is a very serious cancer, we now have very good treatment options available.