Benign lesions of the bone are tumors that are unlikely to spread from where they form on any bone throughout the body, although usually they appear on only the largest bones. There are many different types of tumors that can appear, the most common are endochondromas, osteochondromas, nonossifying fibromas, chondroblastomas, osteoid osteomas, osteoblastomas, periosteal chondromas, giant cell tumors and chondromyxoid fibromas. On the other hand, benign lesions of the soft tissues are tumors that for in the connective tissue of the body like the muscle, tendons, skin and fat. The most common type of tissue tumors that occur within children are fibromas, hemangiomas, and lipomas. The cause to why benign tumors occur in children isn’t known, but only about 2 of 10 children who have a known family history of tumors get them before they are 10 years of age.