Oftentimes when our veterinarians examine an older dog, its not unusual find at least one or two cutaneous (within the skin) or subcutaneous (just beneath the skin surface) lumps and bumps. Such growths are common by-products of the aging process.
The good news is that most cutaneous and subcutaneous canine tumors are benign. It’s that small population of malignant masses that keeps us on our toes. They are the reason it’s important to have your veterinarian inspect any newly discovered lumps and bumps your dog develops. The smaller a cancerous growth is at the time of treatment, in general, the better the outcome.
Pet your dog!
In terms of “lump and bump patrol,” your first order of business is to pet your dog. No doubt you and your best buddy already enjoy some doggie massage time. Even better is a is a more methodical petting session. Once a month, slowly and mindfully slide your fingers, palm sides down, along your dog’s body. Move systematically from stem to stern while inspecting for any new lumps or bumps.
Also, look and feel for changes in the size or appearance of those previously discovered. Any new findings should be addressed with your veterinarian who relies upon your help with this surveillance. Imagine your vet trying to find a tiny growth on a shaggy Sheepdog or Sheltie during the course of a single exam. Some lumps and bumps are bound to be missed without your assistance.
Its always a good idea to continue to observe the new lump once a week. Examining it more frequently can make it difficult to accurately assess change. If the mass is growing, or otherwise changing in appearance, or seems painful, its best to have it checked out sooner rather than later.
Fine needle aspirate for cytology
If a newly discovered growth is large enough, the usual first step your veterinarian will recommend is a fine needle aspirate for cytology. The purpose of this step is to attempt to clarify the cell type within the mass, and whether it is benign or malignant.
Collection of a fine needle aspirate is a simple process that is easy on the dog and rarely requires any sort of sedation. Using a needle no larger than the size of a vaccination needle along with some gentle suction, your vet will remove some cells from the growth. These cells are then put on to glass slide, stained, and evaluated under the microscope.
Some cytology interpretations are a slam-dunk, and can readily be interpreted by your family vet. Others require the eyeballs of a specialist — a clinical pathologist who works in a veterinary diagnostic laboratory. Remember, the goal of the cytology testing is to determine the underlying cell type, therefore whether the growth can be left alone or requires more attention. Fine needle aspirate cytology is often (but not always) definitive. If the results do not provide clarity, a surgical biopsy of the mass may be recommended.
Its not always a great idea to push ahead with surgery without benefit of fine needle aspirate cytology. If the cytology were to reveal a malignancy (cancer), screening the rest of the body for metastasis (spread) is the logical next step. If metastasis is discovered, removal of the originally discovered mass is unlikely to provide any benefit. Rather, such surgery will only subject the patient (and the client’s pocketbook) to a needless procedure. Leaping into surgery to remove a mass without the benefit of cytology is risky business.
The importance of histopathology
If your veterinarian surgically removes a growth from your dog, its always a great choice is to have the mass submitted to a veterinary diagnostic laboratory for histopathology (biopsy). There, a veterinary pathologist will evaluate paper-thin slices of the mass under the microscope to confirm the identity of the mass. This test also determines if the mass was removed with clean margins, which lets your vet know if they were able to remove ALL of the dangerous cells. It can be extremely difficult to get clean margins on areas where there is a lot of skin tension, such as a limb, toe, or paw.
Even if a fine needle aspirate cytology indicated that the growth was benign, histopathology is warranted. On occasion, the pathologist discovers something quirky such as a malignant tumor within the center of one that is benign.
If histopathology is not affordable, ask your vet to place the growth that was removed in a small container of formalin (preservative) and it can be held for a later date. This way, should multiple masses begin growing at the surgery site or should your dog develop a tumor at another site, you will still be able to request histopathology on the original sample.
Lumps and bumps are a very normal part of the canine aging process. Teaming up with your veterinarian to assess them on a regular basis is the very best way to insure that they never create a health issue for your wonderful dog.
Source: http://speakingforspot.com/, Nancy Kay, DVM Diplomate, American College of Veterinary Internal Medicine