Introduction
Most pet owners will find unexplained lumps and bumps on their dog at some point in time. While these may be harmless, sometimes they are cancerous masses or other lesions that require prompt medical attention. A veterinarian is the best person to assess skin tumors and determine if a given bump is a benign pimple, cyst, skin tag or abscess, or if instead it could be malignant and far more serious. One of the most common initial procedures used to assess skin tumors is called a “fine needle aspirate.” During this procedure, the veterinarian will gently insert a needle into the lump, pull back on the syringe stopper to draw out some of the fluid and cells inside the mass and then “squirt” the sample onto glass slides for examination under a microscope. Other diagnostic procedures may be required as well.
Treating Skin Tumors Found on Dogs
Benign Tumors
Uncomplicated benign skin tumors that consist merely of fat (lipomas) are easily identifiable under a microscope using the fine needle aspirate diagnostic procedure described above. Often, these tumors do not require treatment, but can be surgically removed for cosmetic reasons or if they seem to bother the animal. Many owners decide to have lipomas removed because they don’t like the look or feel of them on their dogs.
Malignant Tumors
Skin masses that are diagnosed as malignant or are prone to becoming metastatic are normally removed at the first opportunity. Aggressive surgical resection, with wide margins around the tumor site, is the treatment of choice. The removed tissue will be submitted for histopathologic examination, so that the veterinarian can assess whether all the tumor cells associated with the mass have been removed. If it appears that malignant cells extend close to the surgical margins, a second surgery may be necessary. Radiographs (x-rays) may be recommended to determine whether malignant forms of cancer have spread to nearby lymph nodes or other areas, particularly the bone marrow and lungs. Blood tests will be conducted as well. In many cases, radiation and/or chemotherapy treatments will be used in addition to surgical resection to improve the success rate. Owners must recognize that malignant tumors can recur post-operatively, despite whatever heroic treatment efforts are taken by the veterinary team, so regular rechecks are important.