Comprehensive Cancer Centers looks at the fundamentals of skeletal structure, as well as how bone cancer can occur and can be treated.
The human skeleton is a remarkable feat of biological engineering. It provides the body’s framework, protects vital organs, and allows an extraordinary range of movement. Despite their strength and resilience, the bones that make up skeletons are vulnerable to disease, including cancer. Although bone cancer is far less common than cancers of the lung, breast, or prostate, it remains one of the most complex and challenging areas of oncology for the physicians at Comprehensive Cancer Centers.
Understanding bone cancer begins with distinguishing between its two main forms. Primary bone cancer originates within the bone itself. Secondary, or metastatic, bone cancer develops elsewhere in the body and then spreads to the skeleton. Metastatic bone cancer is far more common, especially among older adults. Primary bone cancer has a distinct biology and disproportionately affects children, adolescents, and young adults. Examining this disease requires an understanding of its different types, cellular origins, symptoms, diagnostic challenges, and the continually advancing field of multimodal treatment.
To understand bone cancer, it is important to first examine the structure of healthy bone. Bone is not a static material but a living tissue that constantly remodels itself through a balanced cycle of formation and breakdown. Osteoblasts create new bone, while osteoclasts remove old or damaged tissue. When genetic mutations disrupt this carefully regulated process, cells can begin dividing uncontrollably, eventually forming a tumor. In primary bone cancer, the cell type that undergoes malignant transformation determines the specific classification of the disease.
The most common type of primary bone cancer is osteosarcoma. This malignancy arises from primitive bone-forming cells called osteoblasts. Because these cells are especially active during periods of rapid skeletal growth, osteosarcoma has a distinctive bimodal age distribution. It occurs most frequently during adolescence, when growth is fastest, and appears again later in life, often in association with chronic disorders such as Paget’s disease. Osteosarcoma usually develops in the long bones, particularly the femur, tibia, and humerus, with many tumors forming near the knee. The cancer cells produce an immature and disorganized form of bone known as osteoid. As the tumor enlarges within the rigid bone, it destroys healthy tissue, penetrates the outer cortex, and may eventually invade nearby muscles and other soft tissues.
Another major form of primary bone cancer is chondrosarcoma, which develops from cartilage-producing cells. Unlike osteosarcoma, chondrosarcoma primarily affects middle-aged and older adults, with most cases diagnosed between the ages of forty and seventy. Cartilage is the flexible connective tissue found in joints and growth plates, and these tumors commonly arise in the pelvis, hip, or shoulder girdle. Their behavior varies considerably. Low-grade chondrosarcomas tend to grow slowly and can resemble benign cartilage tumors, whereas high-grade forms are highly aggressive and frequently spread to the lungs early in the disease.
A third important type of primary bone malignancy is Ewing sarcoma. Named after pathologist James Ewing, this highly aggressive cancer occurs mostly in children and young adults, with the highest incidence between the ages of ten and twenty. Unlike osteosarcoma and chondrosarcoma, the cell of origin remained uncertain for many years. Current evidence suggests that Ewing sarcoma arises from primitive neuroectodermal or mesenchymal stem cells. At the genetic level, it is characterized by a specific chromosomal translocation, most commonly involving chromosomes 11 and 22, which creates the abnormal fusion gene EWS-FLI1. This fusion gene functions as a powerful oncogene, driving the rapid and uncontrolled growth of small, round blue cells within the bone marrow. Ewing sarcoma most often affects the pelvis, femur, tibia, and the bones of the chest wall.
In addition to these primary cancers, the skeleton is one of the most common sites for metastatic disease. When patients are told they have cancer in the bones, it is statistically more likely to be secondary bone cancer. Cancers of the breast, prostate, lung, kidney, and thyroid have a particular tendency to spread to bone, a phenomenon often explained by the seed and soil hypothesis. Cancer cells travel through the bloodstream or lymphatic system and establish themselves within the highly vascular bone marrow. Once there, they interfere with the normal process of bone remodeling. Some metastatic tumors are osteolytic, stimulating osteoclasts to break down bone and create weak, hollow areas. Others are osteoblastic, triggering excessive but poorly organized bone formation that lacks normal strength. Whether the cancer is primary or metastatic, its presence within the skeleton produces a predictable series of clinical symptoms.
Pain is the most common and persistent symptom of bone cancer. In its early stages, the discomfort may be mild, intermittent, and easily mistaken for a sports injury, growing pains in children, or arthritis in adults. As the tumor enlarges, however, the pain becomes deeper, more constant, and increasingly resistant to rest. One of the hallmark features of bone cancer pain is its tendency to worsen at night, often waking patients from sleep. This nighttime discomfort is believed to result from inflammatory cytokines and rising pressure within the bone as circulation and body temperature change during rest. As the disease progresses, localized swelling and tenderness may also develop, particularly when the tumor is located near a joint or has extended through the cortex to form a palpable soft tissue mass.
As the tumor continues weakening the bone, its structural integrity may eventually fail. This can result in a pathologic fracture, which is a break caused by ordinary activities that would not normally produce a fracture, such as stepping off a curb or turning over in bed. In some patients, the sudden pain of a pathologic fracture is the first sign of an underlying malignancy. Tumors located near joints may also interfere with normal movement, producing a limp or a reduced range of motion. Although less common during the early stages, systemic symptoms such as unexplained weight loss, fatigue, fever, and anemia may also occur. Anemia is particularly common in Ewing sarcoma because the disease often involves the bone marrow.
Diagnosing bone cancer requires a careful, multidisciplinary approach that combines medical imaging, laboratory testing, and histopathological analysis. Evaluation typically begins with a standard X-ray, which can reveal important clues such as the destructive moth-eaten appearance of lytic lesions, the sunburst pattern of aggressive bone formation, or Codman’s triangle, where the periosteum is lifted by the expanding tumor. Magnetic resonance imaging (MRI) provides a more detailed assessment of the tumor’s size, boundaries, and relationship to surrounding nerves and blood vessels. Computed tomography (CT) scans are used both to evaluate bone anatomy in greater detail and to examine the lungs, the most common site of metastasis for primary bone cancers.
To determine whether cancer has spread throughout the skeleton, physicians often use nuclear medicine techniques or positron emission tomography (PET) scans. These studies identify areas of increased metabolic activity and bone turnover, revealing lesions that may not yet appear on conventional X-rays. Although imaging provides a detailed map of the disease, a definitive diagnosis requires a biopsy. During this procedure, a small tissue sample is obtained using either a specialized needle or an open surgical technique. A musculoskeletal pathologist then examines the sample under a microscope to determine the tumor’s exact type and grade. Biopsies must be carefully planned because an improperly placed biopsy tract can spread cancer cells into healthy tissues and complicate later surgical treatment.
How Comprehensive Cancer Centers Treats Bone Cancers
Once a diagnosis and stage have been established, an individualized treatment plan is developed by the oncologists at Comprehensive. Historically, primary bone cancers carried a poor prognosis, often requiring immediate amputation and resulting in low survival rates because microscopic metastases frequently went undetected. Modern multimodal therapy has transformed these outcomes. Today, osteosarcoma and Ewing sarcoma are typically treated with a combination of neoadjuvant chemotherapy, surgical removal of the tumor, and adjuvant chemotherapy. Neoadjuvant chemotherapy is given before surgery to shrink the primary tumor, assess its response to treatment, and eliminate microscopic cancer cells that may have already spread throughout the body.
Following chemotherapy, the primary tumor is surgically removed. Advances in surgical techniques, biomedical engineering, and medical imaging have made limb-salvage surgery the preferred option in most cases, replacing amputation whenever possible. During limb-salvage procedures, surgeons remove the affected section of bone along with a generous margin of healthy tissue to minimize the risk of recurrence. The resulting defect is reconstructed using either an allograft from a donor or a sophisticated endoprosthesis, an internal metal implant designed to match the patient’s anatomy or, in children, to accommodate future growth. Amputation is generally reserved for cases in which the tumor involves major nerves or blood vessels or when limb preservation would leave the patient with little functional use of the extremity.
Because Ewing sarcoma is highly sensitive to radiation, radiotherapy remains an important component of treatment, especially when tumors are located in areas that are difficult or impossible to remove surgically, such as the skull or spine. In contrast, chondrosarcoma responds poorly to both chemotherapy and radiation, making wide surgical excision the primary and often only effective treatment for this disease.
Treatment does not end once the final therapy session is completed. Long-term surveillance is an essential part of survivorship, requiring regular imaging of both the original tumor site and the lungs to detect recurrence as early as possible. Survivors may also face ongoing challenges related to rehabilitation, maintenance of prosthetic devices, and the long-term effects of intensive chemotherapy, including cardiac or kidney damage. Despite these obstacles, continued advances in immunotherapy, targeted genetic treatments, and biomaterials are creating new opportunities for improved care. These emerging therapies offer hope for more effective treatments and better long-term outcomes for individuals facing the disease.
Comprehensive Cancer Centers Can Help
Physicians at Comprehensive Cancer Centers provide a variety of treatment options for patients, with bone cancers with all treatments being done in Southern Nevada.
To schedule an appointment, please call 702-952-3350.
The content in this post is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.