The early symptoms of osteosarcoma include pain, which initially is intermittent. As the condition progresses, this intermittent pain gradually becomes constant, and the intensity of the pain is parallel to the severity of the osteosarcoma, meaning the more severe the osteosarcoma, the more intense the pain. Additionally, you can also feel a lump forming on the affected limb, and this lump is clearly tender to touch. The third symptom is the occurrence of a limp. This limp is due to pain, which prevents the patient from bearing weight and walking for extended periods. Lastly, all osteosarcomas present symptoms such as anemia, pathologic fractures, and a low-grade fever.