by Christopher Forsythe, DVM

Hello, readers. Welcome to Health Matters. My name is Dr. Christopher Forsythe. I am a small-animal veterinarian practicing in Sonoma. Each month I will contribute a pet veterinary care topic with the hope of tweaking your interest, making you smile, and educating you about your pets.

I hear this every week in my small animal practice, sometimes more than once a day. A pet comes in with a lump on his body, either newly discovered or something that has been slowly growing over time. Perhaps I’m doing an exam on a pet and feel a lump or a bump on some part of a pet’s body. Lumps and bumps are all part of my job, and I see them more often than Cher sees her plastic surgeon.

Many veterinarians examine lumps and bumps using their education and experience to make a diagnosis without performing any diagnostics to substantiate their hunch. "It’s probably just a lipoma," they often say, "so please just monitor it for growth or other changes." While this conservative approach saves the client’s money and the veterinarian’s time, and avoids having patients undergo further tests, I think that pets deserve a more proactive approach to their health needs. I don’t know a vet alive who could truly diagnose a lump by just looking at it. So if your vet thinks he can, he is in "la-la land!"

That NAGging feeling

Until your vet performs a diagnostic test such as a fine-needle aspiration, the lump or bump on your pet can only really be considered a N.A.G. (neoplasia, abscess, granuloma) lesion. So, well-meaning veterinarians might presume that a palpable mass is a lipoma, or benign fatty mass, but the truth is it could be something much more serious.

The N in N.A.G. stands for neoplasia or cancer, which is of great concern in small animal medicine. Dogs and cats get many kinds of cancer, including squamous cell carcinoma, mast cell tumor, melanoma, fibrosarcoma, lymphoma, and osteosarcoma, to name but a few. As in human medicine, it is important to diagnose early in order to provide the best possible treatment options to the guardians. Benign masses consist of growths such as lipomas, histiocytomas, papillomas, basal cell tumors, sebaceous gland tumors, sweat gland tumors, fibromas, and more.

The A stands for abscess. Abscesses are common in small animal medicine, and can present as firm swellings that appear almost tumor-like.

The G in N.A.G. stands for granuloma, a type of mass that is benign and consists of inflammatory cells from the immune system combined with connective tissue. These masses are often the result of chronic stimulation, allergy, or from foreign material that gets walled off by the body.

Staring at the lump won’t make it go away!

They say a watched pot never boils, and usually a watched mass never magically disappears. Diagnosis of lumps and bumps on your pet begins with a fine needle aspirate, which means sticking a needle into a mass and sucking out some cells to view with the microscope. I tend to aspirate every mass, or at least recommend this to the client. Another diagnostic option is biopsy, which involves snipping out a small piece of the tissue for histopathology. Finally, there is the option to remove the mass surgically. This option is particularly recommended if the mass is cancerous and can be removed successfully with clean margins. Depending on the tumor type, the veterinarian will want to make sure the tumor has not already metastasized (spread to other organs) before removal. X-rays are used to gauge the depth and invasiveness of the mass. They make it possible to determine, along with manual palpation, the feasibility of removing a mass successfully, and with clean margins ("room to spare" gained by removing surrounding tissue).

Abby: a case in point

Abby Dimick won me over the first moment she swaggered into my office. A lumpy, bumpy, arthritic lab mix with a never-ending smile and a dancing tail wag that made you want to shake it like Elvis Presley (in his thinner days). Her Crest smile and happy countenance truly ignited my love for her and made me glad to call her my patient and friend. Unfortunately, her lumps had not read the rule books; they were growing all over her body. The largest one was the size of a huge grapefruit sitting smack dab in the middle of her chest, making Abby look like Pamela Anderson in a Picasso painting.

Ten to 12 other masses abounded, each firm and irregular and well circumscribed. A fine needle aspirate revealed fat cells under the microscope, confirming a diagnosis of lipomas, or fatty tumors. An X-ray of the large tumor on Abbey’s chest showed that this mass was an invasive lipoma, one that was dissecting down through the muscle layer, meaning it would be more challenging to remove.

Mrs. Dimick, wanting what was best for her Sonoma Goddess, opted for me to remove the unsightly and uncomfortable masses from her pet using a C0² laser. Abby was tired of people petting her and commenting on her bulging protuberances. Instead she longed for people to be able to focus on her dazzling smile and beguiling tail.

One lump or two?

I made a large incision over the skin on the grapefruit- sized mass using my C0² laser. Slowly, I dissected the layers of tissue away until I reached the layer of fat comprising the tumor. With careful dissection I was able to isolate the bulk of the mass and after several minutes was ready to attempt peeling the base of the mass from her breast muscles. Using the laser for both cautery of blood vessels and tissue removal, the large bulky mass slowly surrendered to me, and after two hours of surgery, Abby was free of all of her masses and significantly lighter! With appropriate suture closure and pain medication, Abby was a happy girl later that afternoon, and smiled happily as she left the hospital the next morning.

Abby, like so many pets, benefited from a doctor who likes to aspirate masses rather than watch them grow and change, and an owner who was willing to have her beautiful pet cared for so she could go from a lump o’ love back to being a smooth, sweet Sonoma Goddess.