Soft tissue sarcoma (STS) is a collective name for a group of malignant (cancerous) tumors which typically arise from tissue under the skin. Though these tumors can occur anywhere, they most frequently arise on the limbs or anywhere on the outside of the dog’s body. Types of STSs include fibrosarcomas, perivascular wall tumors (previously called hemangiopericytoma), and peripheral nerve sheath tumors. Affected dogs are typically 10 years of age or older.
Soft tissue sarcomas can metastasize (spread) to nearby lymph nodes and the lungs. A thorough evaluation is necessary and includes blood work, chest x-rays, a biopsy or an aspiration or the mass, lymph node assessment, abdominal ultrasound, and possible a CT scan.
Dogs have two anal glands (sacs), one on either side of the anus. While it isn’t common, a tumor of the anal sac can form in one or, rarely, both glands. Biopsy may show the tumor is an anal gland adenocarcinoma (AGASACA), anal sac carcinoma, or an apocrine gland carcinoma. All of these tumors have the same prognosis and are treated with the same therapy. These tumors have the potential to spread to other body parts, especially the lymph nodes, liver, and lungs. In addition, this cancer can elevate the calcium in the dog’s body, which can eventually lead to kidney damage.
The term brachycephalic comes from the Greek words brachy, meaning “short” and cephalic, meaning “head.” Brachycephalic dog breeds have flat faces with shortened muzzles. Unfortunately, the shortened muzzles and snouts often mean that the throat and breathing passages are also undersized or flattened. The term Brachycephalic Obstructive Airway Syndrome, or BOAS, refers to multiple anatomic abnormalities that can lead to breathing difficulties and other health problems for these dogs.
As many as six anatomic abnormalities make up BOAS. Not all dogs have all six abnormalities, but the more a dog has, the greater their clinical signs. The table below lists the medical names for the abnormalities followed by their definition.
Anatomic Abnormality
Definition
Stenotic nares
Nose holes are too narrow or collapse inward during inhalation
Extended nasopharyngeal turbinates
Air filtering bones inside the nose extend into the back of the throat
Elongated soft palate
Roof of the mouth is too long
Laryngeal collapse
Voice box collapses, making air passage difficult
Hypoplastic trachea
Windpipe is too narrow for the dog’s size
Everted laryngeal saccules
Pouches inside the voice box turn inside out and block airflow
All of these anatomic abnormalities lead to a decrease in air flow in and out of the lungs. The abnormalities associated with BOAS cause affected dogs to easily overheat because they cannot effectively cool themselves through panting. Stress, anesthesia, and exercise are also difficult for these dogs. Finally, dogs with BOAS often have lower blood oxygen levels as compared to non-brachycephalic breeds.
Urethral obstructions occur when the urethra (the tube through which urine exits the body from the bladder) is blocked. These blockages can be caused by plugs (a buildup of protein, cells, or minerals from the bladder), urinary stones, and/or inflammation. While both male and female cats can develop a urethral obstruction, it is most often seen in males because of their longer and narrower urethra.
Urethral obstructions are a life-threatening emergency. If the blockage lasts too long and urine is unable to exit the body, the buildup can damage the kidneys and cause the bladder to rupture.
When cells or tissues in the body begin to grow abnormally and uncontrollably, this is called neoplasia. A tumor, or a swelling of the part of the body, is a created as a result of uncontrolled cell growth. Tumors can be either benign or malignant. A benign tumor is not invasive, meaning the rapidly growing cells are localized to one area and do not invade the rest of the body. However, malignant tumors are made up of cells that spread throughout the body (metastasize) and harm other tissues, most commonly the lung and lymph nodes. The term “cancer” specifically refers to malignant tumors which spread and grow rapidly throughout other areas of the body.
Cancer is not one disease, but hundreds. Cancer can be grouped into three main categories:
Carcinomas – carcinomas are formed by epithelial cells, which are the cells that cover the inside and outside surfaces of the body. Tumors of the anal gland, mammary gland, and bladder are types of carcinomas in dogs and cats.
Hematopoetic tumors – blood cancer, or hematopoetic tumors, include mast cell tumors, leukemia and lymphoma. At the Schwarzman Animal Medical Center, lymphoma is a common cancer treated in both dogs and cats. Lymphoma in Dogs Lymphoma in Cats
Sarcomas – sarcomas are tumors formed by cells from bone and soft tissues, including muscle, fat, blood vessels, lymph vessels, and fibrous tissue (such as tendons and ligaments). Examples of sarcomas in dogs include soft tissue sarcoma, hemangiosarcoma, and osteosarcoma.
