Final answer:
The malignant bone tumor that typically forms within the metaphysis of long bones is called osteosarcoma. It originates in osteoblast cells and is most commonly found in the metaphyseal region of the femur, tibia, or humerus. Osteosarcoma is an aggressive cancer affecting the growth areas of long bones.
Step-by-step explanation:
The malignant bone tumor that usually forms within the metaphysis of long bones is known as osteosarcoma. This type of cancer originates in the osteoblast cells that form new bone tissue. Osteosarcoma is characterized by aggressive growth and often occurs in the metaphysis, which is the narrow area between the diaphysis, or shaft, and the epiphyses, or ends, of a long bone.
Long bones continue to grow during childhood and adolescence through a process occurring at the epiphyseal, or growth, plate. When growth ceases in early adulthood, the epiphyseal plate is replaced by bone, becoming an epiphyseal line. Osteosarcoma most commonly affects the metaphyseal region of long bones such as the femur, tibia, and humerus.
Understanding the anatomy of a long bone is crucial for recognizing how osteosarcoma and other types of bone tumors affect the skeletal system. The epiphysis is filled with spongy bone and red marrow, where hematopoiesis production of blood cells occurs. The diaphysis contains the medullary cavity with yellow marrow, and the metaphysis houses the growth plate during development.