Liposarcomas are uncommon tumors in all household animals. The majority are known to occur in older male dogs in which they typically grow on the chest and legs. Beagles and Shetland Sheepdogs are most at danger for liposarcomas. Liposarcomas are lumpy and can be squashy or firm. They are malignant tumors with a low probability for spreading to other sites. Extensive surgical removal of both tumor and the surrounding tissue is most frequently recommended. Follow up radiation treatment may be required as recurrence is common.
Lipomas are defined as benign tumors of adipose tissue (fat) commonly found in dogs. They usually develop in elderly, overweight, female dogs, mainly forming near the top of the legs and on the trunk. The most prone breeds are Doberman Pinschers, Miniature Schnauzers, Labrador Retrievers, and mixed-breed dogs. Lipomas characteristically emerge as spongy, occasionally slender, discrete lumpy masses in elderly, neutered male dogs. Diffuse lipomatosis, a rare variation of this tumor, has been reported in Dachshunds. Virtually the whole skin is affected, leading to major skin folds on the trunk and neck.
It is difficult to establish the edges of most lipomas as they tend to join with healthy fat tissue around them. It is necessary to get a fine needle aspiration so as to exclude other kinds of tumors that may imitate lipomas, for example mast cell tumors.
Lipomas should not be ignored, regardless of their benign nature. Some are likely to grow, thus becoming impossible to differentiate from liposarcomas or infiltrative lipomas. Surgical removal is the most appropriate treatment. For effective treatment, a weight loss diet should be started a number of weeks prior to surgery, thus making it easier for the surgeon to recognize the boundaries of the tumor and eliminate it all.
Infiltrative Lipomas in dogs are quite rare, mostly being seen on the chest and legs of middle-aged females. The most susceptible breeds are Doberman Pinschers, Miniature Schnauzers, Labrador Retrievers, and mixed-breed dogs. These tumors are spongy, swellings in the fat layer beneath the skin, spreading to connective tissue and deep muscle. Invasive lipomas are regarded as partial malignant sarcomas that do not spread to other areas. The preferred treatment for infiltrative lipomas is surgery, not only to remove the tumor but also some normal tissue around it. There are cases where a limb may have to be amputated.