There is no scientifically proven herbal or natural treatment for osteosarcoma. While some herbal supplements may be recommended to strengthen the body's general defense system, their direct efficacy in treating osteosarcoma has not been scientifically established. The risk of disease recurrence can emerge at different time frames, such as 3 months or 2 years after treatment. However, the likelihood of recurrence significantly decreases after two years post-treatment.