Introduction to osteosarcoma

Tumor, what a scary word, it scares so many people. There are many types of tumors, and the conditions of each lesion are different. One of them is called osteosarcoma. When it comes to this term, many people don’t understand it or have even never heard of it. So, let us take a look at the overview of osteosarcoma.

Osteosarcoma in children is a malignant tumor that originates in bone tissue. Because tumor cells can directly generate tumor-like bone tissue, it was once called osteosarcoma or osteogenic sarcoma. The incidence rate is highest in children during the period of vigorous bone growth and development or in adolescents with a longer growth and development period. The age of onset is mostly between 10 and 15 years old, and boys are twice as likely to develop as girls. It is prone to occur in the epiphyseal ends of the long bones of the limbs, with the lower end of the femur being the most common, reaching more than 50%; the upper end of the tibia and the upper end of the humerus are second, accounting for about 10 to 20%, and occasionally seen in the pelvis, spine, and ribs. Among malignant bone tumors in children, osteosarcoma ranks first in incidence, accounting for 6 to 8% of malignant solid tumors in children.

According to the different differentiation of tumor matrix, it can be pathologically divided into osteoblastic type, chondroblastic type and fibroblastic type. Most tumors grow in the epiphysis of long bones, causing hypertrophy and deformation, often invading or penetrating the bone cortex, forming a mass in the surrounding soft tissue. The tumor tissue is fish-like, the osteoblastic type is yellow-white and hard; the chondroblastic type is gray-blue and tough; the fibroblastic type is dark red or gray-yellow, soft, with mixed bleeding and necrotic areas. Microscopically, spindle-shaped tumor cells are seen, with large, dark-stained nuclei and mitotic figures. Bone-like tissue is formed between cells. The osteoblastic type is mainly composed of tumor bone, the chondroblastic type has more tumor cartilage components, and the fibroblastic type is mainly composed of tumor cells and less bone-like tissue.

Osteosarcoma, low magnification

This is the microscopic appearance of an osteosarcoma. The sarcoma has very heterogeneous cells that are often spindle-shaped. A large cell with a large nucleus is seen near the center. Reactive new bone islands are also seen.