Osteosarcoma (osteogenic sarcoma) is a malignant primary bone tumor that develops from mesenchymal cells (cells that give rise to bone tissue). As a result of certain reasons, these cells begin to multiply uncontrollably, which leads to formation of a large amount of osteoid (bone tissue), tumor formation and destruction of bone tissue normal architecture.
Osteosarcoma mainly affects long tubular bones of upper and lower extremities (femur, tibia, humerus), but absolutely all bones in the body (pelvic, skull, other flat bones) can be affected.
The disease is characterized by high aggressiveness, rapid spread to surrounding tissues and early metastases development. Metastasis occurs mainly through hematogenous route, therefore, with blood, malignant cells can reach almost all organs and tissues.
Osteogenic sarcoma is the most common primary bone tumor among children. Most often it affects children over 10 years of age, teenagers and young adults. Genetic factors are involved in osteosarcoma development, for example, children who are carriers of hereditary retinoblastoma gene (RB1 gene) or Li-Fraumeni syndrome (TP53 gene) suffer from osteosarcoma more often.
Osteosarcoma is a serious and aggressive disease, but with timely access to specialized medical care and correct modern tactics, it is completely curable. Therefore, if you have the slightest suspicion of this tumor in a child, do not hesitate! Urgently contact the specialists of Pediatric Hematology Oncology Department of Tel Aviv Medical Clinic.
All our specialists are highly qualified and have extensive working experience with patients suffered from bone cancer. Most of them have more than once trained at the best children’s oncology centers in USA and Europe, so there is no doubt about the quality of medical services provided. In their daily work, our doctors are guided by modern global treatment protocols and clinical recommendations based on principles of evidence-based medicine. Along with this, the approach to each patient is purely individual. Developing an examination plan and treatment regimen, doctor takes into account all the smallest details – child’s age, the main diagnosis, the stage of the disease, presence of severe concomitant diseases, the wishes of young patient and his parents regarding to treatment process. Thanks to this approach, we are able to achieve success even in the most difficult situations.
An important advantage of osteosarcoma treating in our medical institution is a multidisciplinary approach. The child is assisted by a whole team of specialized doctors: oncologists, orthopedists, traumatologists, surgeons, plastic surgeons, neurosurgeons, pediatricians, radiation therapists, chemotherapists, rehabilitation specialists, physical therapists, psychologists and other specialists if necessary.
Causes of osteosarcoma
Unfortunately, the exact causes of osteogenic sarcoma development have not been established to date. There are known risk factors that increase the risk of disease in a child:
- Age. The peak incidence occurs between the ages of 10-25 years.
- Gender. Boys get sick more often than girls.
- Previous bone injuries.
- Chronic inflammatory diseases of bone tissue (for example, osteomyelitis).
- Paget’s disease of bone is a precancerous condition with a 5-10% risk of osteosarcoma.
- Negative effects of ionizing radiation in past, for example, radiation therapy for another cancer.
- Li-Fraumeni syndrome.
- Preliminarily diagnosed osteochondroma.
- A history of retinoblastoma or gene presence for retinoblastoma development.
Symptoms of osteosarcoma in children
For a long time, osteosarcoma can occur latently (absolutely without symptoms). Most often, the first sign of osteosarcoma is pain in the area where the tumor is located. At first it is mild, but can intensify after physical activity. In children, such pain is often mistakenly perceived as growing pains, consequences of muscle strain, or traumatic injury. Therefore, in the early stages, osteosarcoma is rarely diagnosed, and patients are assigned non-existent diagnoses.
As the disease progresses, the pain intensifies, becomes more frequent and becomes disturbing over time even at rest, especially at night.
As the tumor grows, the following symptoms appear:
- Visible tumor at the site of tumor projection.
- The appearance of a pronounced venous pattern on the surface of skin.
- Impaired function of joint that is located near osteosarcoma.
- Neurological disorders that develop due to compression or irritation of nerves in area where the tumor is located (numbness, burning sensation, tingling, etc.).
Sometimes the first symptom of osteosarcoma is a pathological fracture of affected bone. It can also occur against the background of pre-existing symptoms. The cause of a low-energy fracture is destruction of bone tissue normal structure, as a result of which it loses strength and elasticity. In such situation, even a slight load can lead to fracture formation.
If metastases develop with osteosarcoma, general symptoms appear:
- increased body temperature;
- weight loss;
- lack of appetite;
- chronic anemia;
- nausea and vomiting;
- insomnia;
- headache;
- constant weakness and fatigue.
If you notice one or more symptoms in your child, don’t waste time! Seek modern and qualified help from specialists of Pediatric Hematology Oncology Department at TAMC.
Modern diagnostics methods of osteogenic sarcoma
To establish osteosarcoma diagnosis, a complex of tests and examinations is required, including:
- Study of life history, medical history, risk factors identification, child’s medical examination by the leading oncologist of the department, blood tests to determine the general health of the child, concomitant medical problems presence.
- Skeleton digital radiography.
- CT scan of abdomen, chest and other parts of the body to determine whether osteosarcoma has spread throughout the body (search for metastases).
- MRI of affected bone is necessary for visualization, assessment of tumor size, location, and surgical planning.
- Bone scintigraphy, as well as PET-CT or PET-MRI, are necessary to scan the whole body and look for distant metastases.
- A biopsy is needed to make the correct diagnosis and select the most effective treatment protocol.
During a biopsy, doctor obtains a tissue sample from tumor. Depending on tumor location, an incisional or needle biopsy may be required. We send all materials for testing to the best pathology laboratories in Israel. Thanks to this approach, we are absolutely sure of diagnosis correct and subsequent complex therapy.
Innovative molecular genetic tests of tumor cells are also available to TAMC patients. Thanks to such diagnostics, oncologists can select the most effective treatment protocols, because the response to certain drugs action depends on the type of changes in cancer cells. An example of such modern test systems are Foundation One and Caris Molecular Testing. They allow us to determine certain types of mutations in tumor cells, as well as the presence of certain receptors on the surface. These data are used to create individual immunobiological therapy drugs or to select targeted drugs.
Prognosis for osteosarcoma in children
The prognosis for osteogenic sarcoma in children depends, first of all, on the stage of pathology. If a patient is diagnosed with a single localized lesion, the probability of 5-year survival is 65-70%. If the disease has spread (metastatic osteosarcoma), the 5-year survival rate is 30%.
Factors that influence on osteosarcoma prognosis:
- tumor location and size,
- tumor spread,
- the possibility of complete surgical tumor removal,
- tumor response to complex treatment,
- primary disease or relapse.
Osteosarcoma modern treatment
Treatment of osteosarcoma in Pediatric Oncology Department of TAMC is carried out according to modern clinical protocols. But the tactics in each individual case are developed strictly individually, depending on osteosarcoma stage and characteristics of tumor cells. In most cases, complex therapy is indicated, which includes:
- surgery;
- polychemotherapy, as well as application of modern immunobiological drugs;
- radiation therapy is used very rarely, as it is ineffective due to the low sensitivity of osteosarcoma cells to ionizing radiation.
Surgery is the main treatment component for a child with osteosarcoma. It can be refused only in cases where the tumor process has reached the last stage of development, or the child has multiple metastases that cannot be removed.
Our oncological surgeons always strive to avoid complete limb amputation, which was relevant only yesterday. All efforts of specialists are aimed at preserving the limb; only the affected areas and a small area around them are removed. This possibility exists in 80% of osteosarcoma cases. Subsequently, special bone cement or an implant from patient’s own bone tissue is used to reconstruct the limb. TAMC patients have the unique opportunity to use bone implants printed on medical 3D printers.
Surgery to replace the lost joint may also be required (if the tumor has spread to it). High-quality endoprosthetics, the techniques of which our specialists are proficient in, return the child to a full life.
Stereotactic radiosurgery is most often used to destroy inoperable osteosarcomas and their metastases in lungs, brain and other organs. The advantages of stereotactic radiosurgery are absolute non-invasiveness, painlessness, high efficiency and safety. As a result of exposure to high-dose ionizing radiation, cancer cells are precisely destroyed, and healthy tissues are almost not affected, since they receive minimal doses of radiation.
Chemotherapy for osteosarcoma is almost always prescribed. The following drugs are used in treatment protocols: doxorubicin, cisplatin, methotrexate, cyclophosphamide. For localized osteosarcoma, polychemotherapy may not be used if the tumor can be completely removed surgically.
Recently, clinical research has been actively conducted on the development of targeted therapy using monoclonal antibodies that block insulin growth factor receptors and signaling pathways of malignant cells. Targeted drugs are considered a promising direction in bone cancer treatment, including osteosarcoma. The following targeted agents are being studied for osteosarcoma treatment: Dinutuximab (Unituxin), Pazopanib (Votrient), Sorafenib (Nexavar), Everolimus (Afinitor), Temsirolimus (Torisel).
Monoclonal antibodies specifically target cancer cells, causing their uncontrolled division to stop and the tumor stops growing. Thanks to this selectivity, these drugs do not affect healthy cells in the body, unlike chemotherapy, and patients tolerate the treatment much easier.
