Cartilage forming tumorsChondromaBenign tumors of hyaline cartilage probably develop from slowly proliferating rests of growth plate cartilage Age: 30-50Site: located in the metaphyseal region of tubular bones ( short tubular bones of the hands and feet)Usually solitaryBut may multiple in:Ollier disease : multiple chondromas involving one side of the bodyMaffucci syndrome: Multiple chondrmas with soft benign vascular tumors( angiomas) of soft tissue.
Enchondromas : arise within the medulla Juxtacortical chondromas: arise on the bone surface
OsteochondromaOsteochondromas are also called exostosesIt is the most common benign tumor of bone
Site: metaphysis of long tubular bones, especially about the knee
Male-to-female ratio of 3 : 1
Benign cartilage-capped outgrowths attached by a bony stalk to the underlying skeleton.
Development over time of an osteochondromabeginning with an outgrowth from the epiphyseal cartilage
Solitary osteochondromas are usually first diagnosed in late adolescence and early adulthoodUsually follow a benign course.
Multiple osteochondromas become apparent during childhood, occurring as multiple hereditary exostosis, an autosomal dominant disorder. Rare sarcomatous change.
ChondrosarcomaMalignant bone forming tumor.Age: most patients are age 40 or older Site: Arise in the pelvis, shoulder, and ribs Men to female ratio: 2-1. Classified according to site and histologic variants - intramedullary - juxtacortical Metastasize hematogenously to the lungs and skeleton
A. Giant cell tumors (osteoclastoma )Locally malignant tumor of bone
Age: occurs between 20 40 years of age.
Site: arises in the ends of long bones particularly in relation to knee joint, jaw, radius and clavicle.
X ray : large, lytic, and eccentric (soap bubble appearance)
Causes eccentric expansion of the affected bone and becomes covered by a thin shell of bone that yields under pressure giving (egg shell crackling). Infiltrates the surrounding tissues. The cut section shows areas of hemorrhage, necrosis and cyst formations4% metastasize to the lungsComplications: 1- Pathological fracture 2-It may change into frankly malignant tumor
B. Ewing sarcomaAnaplastic malignant bone tumorAge: 10-20 Site: Diaphysis of femur, tibia, ribs and pelvis are the favored sites.Male predominanceCharacterized by an 11;22 translocationIt follows an extremely aggressive course with early metastases
Tumor-like lesionsFibrous bone defect30-50% of all children older than age 2Developmental defects rather than true neoplasms. Majority are smaller than 0.5 cm and arise in the metaphysis of the distal femur or proximal tibia 50% are bilateral or multiple Larger lesions (5-6 cm) develop into nonossifying fibromas.
Fibrous dysplasiaUnknown origin and develops at any age in the long bones. Pathology: Fibrous proliferation intermixed with poorly formed, haphazardly arranged trabeculae of woven bone (not line by osteoblasts) progressively replace normal bone.Types: a- Monostotic: Affecting one bone. b- Polystotic: Affecting more than one. The affected part is expanded by grey white fibrous tissue which replaces the medulla and produce thinning of the cortex.Complications: Deformity and pathological fractures. Rarely it transforms into fibrosarcoma.
75% of bone metastasis originate from
Cancers of prostate breast kidney lung thyroidMetastatic lesions are multifocal
Produce a lytic and or blastic reaction