Osteosarcoma

Osteosarcoma is malignant tumor belonging to the primary bone tumors (the 2nd most common primary malignant bone tumor after the exclusion of multiple myeloma). It most often affects the long bones of the lower limb near the knee joint. Osteosarcoma grows in the bone, which it destroys and enters to the soft tissues around the bone. It soon metastasize, especially hematogenously to the lungs, other bones and the brain. It is one of the most common malignant bone tumors, along with chondrosarcoma. The maximum incidence is between the 10 - 20 years of age. Every year, 4 out of one million children are diagnosed with osteosarcoma. náhled| 150 px | Predilection sites for osteosarcoma náhled|Condman'striangle vpravo|náhled| 300 px | Osteosarcoma, on the left normal bone tissue, on the middle osteosarcoma, stained with HE vpravo|náhled| 300 px | Detail of tumor cells

Classification

 * Central (medullary, conventional) osteosarcoma: is a highly malignant tumor (the most common malignant bone tumor), occurs in individuals under 20 years of age (one of the most common tumors in this age group) or in older individuals due to Paget's disease, fibrosis dysplasia and similar pathological bone processes, can affect any bone (more often the femur, tibia, humerus, the transition from the diaphysis to the metaphysis). It soon metastasizes (mainly to the lungs, brain, other bones). It is clinically manifested by persistent dull pain, mild swelling of the bone and mild fever. The tumor begins to grow in the metaphyseal marrow, infiltrates the cortex below the periosteum, and then can grow into the adjacent soft tissues. Osteoid formation is evident microscopically( non-mineralized bases) by tumor cells (the tumor is based on osteoblasts), in different proportions bone, cartilaginous and fibrous tissue are represented (or with wide vascular spaces - telangiectatic osteosarcoma - the most malignant form of osteosarcoma), depending on which type of tissue predominates. with osteosarcomas in:
 * Fibroplastic - spindle cell ligament;
 * Chondroplastic - tumor cartilaginous tissue with atypical spindle cell elements;
 * Osteoplastic - islets or beams of osteoid (can be mineralized), tumor osteoblasts have atypical or polymorphic nuclei (the only sign that it is a tumor process).


 * Peripheral (superficial) osteosarcoma: creates a painful protuberance on the bone surface. The X - ray shows secondary periosteal ossification. It includes, for example, parosteal (juxtacortical) osteosarcoma with a very good prognosis, osteosarcoma with a high degree of malignancy and periosteal osteosarcoma.

Clinical picture

 * Pain in the affected bone, typically resting and nocturnal (ie without stress)
 * With tumor growth, solid swelling occurs, which may not be painful to the touch (typically around the knee joint),
 * At an advanced stage, a pathological fracture of the relevant bone
 * Non-specific general symptoms - night sweating, fever, weight loss
 * Cough and difficulty breathing - lung metastases.

Diagnosis

 * Elevated phosphatase levels are a biochemical marker of bone tumors
 * Simple X-ray (typically areas of osteolysis and newly formed bone, disrupts corticalis, unbounded, has periosteal reaction, Codman's triangle = space bounded by elevated periosteum, bone surface and tumor), NMR
 * Definitive diagnosis histologically (sarcoma stroma, osteoid formation by tumor osteoblasts)
 * CT of the lungs and scintigraphic examination of the skeleton– metastases.

Treatment

 * Chemotherapy (adriamycin, high-dose MTX, leucovorin, cisPt, BCD, ifosfamide)
 * Radical surgical removal of the tumor (amputation or limb saving surgery)
 * Osteosarcoma are generally less sensitive to radiotherapy.

Prognosis
Patients with a radically operated tumor and a good response to chemotherapy have up to an 80% chance of healing. .

Related articles

 * Osteoma
 * Mesenchymal tumors
 * Osteosarcoma (preparation)
 * Ewing's sarcoma
 * Spinal tumors