Synovial Sarcoma in Dogs
Synovial sarcomas are soft tissue sarcomas – malignant cancers – that arise from the precursor cells outside the synovial membrane of the joints and bursa (the fluid-filled, sac-like cavity between joints that helps to facilitate movement). The synovial membrane itself is the layer of soft tissue that lines the surfaces within the joints.
Precursor cells have the ability to differentiate into one or two closely related forms: epithelial cells (skin cells) or fibroblastic (connective tissue) cells. Therefore, the tumor may have cancer resembling both cancers of the skin and of the connective tissue.
Synovial sarcomas are aggressive and highly locally invasive, spreading in greater than 40 percent of cases. They most often spread to the elbow, knee, and shoulder blade regions. They are more common in large-breed rather than small-breed dogs.
Symptoms and Types
You will need to give a thorough history of your dog's health and onset of symptoms. Your veterinarian will then perform a complete physical exam and order standard laboratory tests, including a biochemical profile, a complete blood count, a urinalysis and an electrolyte panel to rule out other non-cancerous causes for your dog's symptoms.
Visual diagnostic techniques will show abnormalities around the affected joints. X-rays of the mass will show that the tumor is involved in both the bone and the joint. To obtain a definitive diagnosis, a biopsy of the soft and bony tissue of the tumor is necessary for histologic evaluation (microscopic analysis of the tissue sample). Using fine-needle aspirates (removal of fluid), the regional lymph nodes (i.e., the lymph nodes of the groin, armpits) should also be sampled and tested for evidence of metastasis (spread).
Something that becomes worse or life threatening as it spreads
An in-depth examination of the properties of urine; used to determine the presence or absence of illness
Small structures that filter out the lymph and store lymphocytes
A type of neoplasm that occurs in connective tissue
Any type of pain or tenderness or lack of soundness in the feet or legs of animals
The process of removing tissue to examine it, usually for medical reasons.
A pouch of fluid that eases the pain of movement in certain areas.
The area between the abdomen and thighs; the inguinal area
The process of removing all or part of a body part; usually refers to a limb (arm or leg) and is done for medical reasons.