Other animals
Risk factors
Osteosarcoma is the most common bone tumor in dogs and typically affects middle-aged large and giant breed dogs such as Irish Wolfhounds, Greyhounds, German Shepherds, Rottweilers, mountain breeds (Great Pyrenees, St. Bernard, Leonberger, Newfoundland), Doberman Pinschers and Great Danes. It has a 10-fold greater incidence in dogs than humans. A hereditary base has been shown in St. Bernard dogs. Spayed/neutered dogs have twice the risk of intact ones to develop osteosarcoma. Infestation with the parasite Spirocerca lupi can cause osteosarcoma of the esophagus. Clinical presentation
The most commonly affected bones are the proximal humerus, the distal radius, the distal femur, and the tibia, following the basic premise "far from the elbow, close to the knee". Other sites include the ribs, the mandible, the spine, and the pelvis. Rarely, osteosarcoma may arise from soft tissues (extraskeletal osteosarcoma). Metastasis of tumors involving the limb bones is very common, usually to the lungs. The tumor causes a great deal of pain, and can even lead to fracture of the affected bone. As with human osteosarcoma, bone biopsy is the definitive method to reach a final diagnosis. Osteosarcoma should be differentiated from other bone tumours and a range of other lesions, such as osteomyelitis. Differential diagnosis of the osteosarcoma of the skull in particular includes, among others, chondrosarcoma and the multilobular tumour of bone. Treatment and prognosis
Amputation is the initial treatment, although this alone will not prevent metastasis. Chemotherapy combined with amputation improves the survival time, but most dogs still die within a year.
Proliferating Angioendotheliomatosis has historically been divided into two groups, (1) a reactive, involuting type and (2) a malignant, rapidly fatal type. : 598 The reactive involuting type, reactive Angioendotheliomatosis is an rare cutaneous condition characterized histologically by a dense proliferation of small capillaries, and occurs in people with various diseases including subacute bacterial endocarditis and end-stage atherosclerotic disease. These people present with various skin lesions and rashes - most commonly on the thighs. Treatment aimed at the underlying condition hastens the resolution of the lesions. The malignant type is an intravascular lymphoma, usually of the diffuse B-cell type, known as intravascular large B-cell lymphoma. It progresses rapidly through involvement of multiple body systems and mortality occurs in less than a year from the initial diagnosis. The average age of diagnosis being 55 years. The causative mechanism is unknown. In a few cases treatment with palliative chemotherapy has been effective. : 598

Classification of Proliferating Angioendotheliomatosis
Proliferating angioendotheliomatosis may be divided into two types:
a reactive type – Reactive angioendotheliomatosis
a malignant type – Intravascular large B-cell lymphoma

Treatment
In few cases palliative chemotherapy is effective. A 30-year-old woman was diagnosed with cutaneous proliferating angioendotheliomatosis. She was treated with a local excision and radiotherapy. See also
List of cutaneous conditions

References
External links


== External links ==