Cancer might be the scariest word in the English language. Unfortunately, man's best friend isn't immune from this dreaded disease. Sarcomas are a type of cancer originating in soft tissues, such as a dog's skin and connective tissue. Prognosis for the disease depends on the type of sarcoma and how early it's caught and treated. According to WebMD, sarcomas account for 15 percent of all canine cancers.
Most sarcomas grow relatively slowly and don't necessarily metastasize, or spread. The majority are single rather than multiple lesions. Canine sarcomas fall into several categories. Fibrosarcomas usually develop in subcutaneous tissue, while the relatively rare liposarcoma starts out in fat cells. Don't confuse liposarcomas with lipomas, which are benign fatty growths. Leiomyomas leimyosarcomas develops in the cells of the dog's smooth muscles. These tend to spread more than other types of sarcomas. Rhabdomyosarcoma originates in the skeletal muscle cells. Lymphangiosarcoma develops in the lymphatic cells, while the very malignant hemangiosarcoma primarily affects the internal organs. Osteosarcoma is bone cancer.
While any dog can develop a sarcoma, some breeds are genetically predisposed to this malignancy. This includes the German shepherd, golden retriever, Doberman pinscher, great Dane, bassett hound, boxer and Saint Bernard. The disease tends to affect males more than females, with larger breeds more susceptible in general. Whatever the breed, sarcomas usually appear in middle-aged and senior dogs.
Whenever you find a strange bump or lump on your dog that doesn't disappear or shrink considerably within a few days, take him to the vet for an examination. It's always possible the bump could be a tumor. Sarcomas generally appear on the legs, neck, head and trunk, or within the mouth. Other symptoms include lack of appetite, weight loss and lethargy.
To diagnose a sarcoma, your vet performs a biopsy or uses fine needle aspiration to draw tissue out of the lump. She'll also take blood for a serum biochemistry panel and a complete blood count. Once sarcoma is confirmed, your vet might refer your dog to a veterinary oncologist. Further testing to determine whether the cancer has spread includes X-rays, ultrasound or computed tomography scans.
The primary treatment for sarcoma consists of surgery to remove the tumor, possibly followed by chemotherapy or radiation. Sometimes, it's not possible to surgically remove a tumor. In that case, consider palliative radiation therapy. Regular doses of radiation for a few days can relieve some of your dog's pain and reduce swelling around the tumor.
By Jane Meggitt
DVM360: Canine Soft Tissue Sarcomas
Ohio State University College of Veterinary Medicine: Canine Soft Tissue Sarcomas
National Canine Cancer Foundation: Soft Tissue Sarcomas
WebMD: Soft Tissue Sarcomas in Dogs
North Carolina State University College of Veterinary Medicine: Soft Tissue Sarcomas in Dogs
About the Author
Jane Meggitt has been a writer for more than 20 years. In addition to reporting for a major newspaper chain, she has been published in "Horse News," "Suburban Classic," "Hoof Beats," "Equine Journal" and other publications. She has a Bachelor of Arts in English from New York University and an Associate of Arts from the American Academy of Dramatics Arts, New York City.