Is it Cancer? Finding a Lump on Your Dog or Cat

This month, we would like to introduce you to three individuals. All three of these pets came to see Dr. Smith because their owners found a new “lump.” However, as you will see, each “lump” had a unique diagnosis and dramatically different treatment options.

Sadie the Mastiff Mix:  fatty lipoma

Russell and Jennifer Lindsay, the owners of Sadie, a 9-year-old Mastiff mix, began to notice several new growths. These growths were soft, somewhat flat masses beneath the skin that did not appear to bother Sadie. When Sadie came in to have them evaluated, Dr. Smith explained that a simple procedure called a fine needle aspirate could give a diagnosis, thus allowing development of a treatment plan.

The needle aspirate is a minimally invasive biopsy technique with a small gauge needle that causes very little, if any, discomfort to the patient. It feels similar to the needle poke involved with a vaccination.

Within a few minutes, Sadie’s biopsy samples were prepared and the three masses were determined to be lipomas. Lipomas are benign fatty tumors commonly found in middle-aged to older dogs. They frequently do not continue to grow and may only need to be removed if they are getting larger, interfering with important structures or impeding movement. Russell and Jennifer will monitor Sadie’s lipomas for growth, but it is unlikely that surgical removal will be needed.

Bruno the Boxer: mast cell tumor

Bruno, a 5-year-old Boxer owned by Rob Tiffany and Kerin Crockett, had a different story. Although Bruno’s mass felt similar to Sadie’s lipomas, his owners astutely noticed that it had a new purple discoloration and seemed to grow larger and sometimes even got smaller!

As with Sadie, a fine needle aspirate was performed. The sample was put onto a microscope slide, stained and viewed under the microscope, resulting in a diagnosis within minutes. Bruno had a mast cell tumor. Although most mast cell tumors have benign behavior, they have the potential for becoming malignant and spreading to other parts of the body. Bruno had his tumor surgically removed under general anesthesia, and is now healed and doing well.

Tica the Bengal Cat:  fibrosarcoma

Finally, we have Tica, a 6-year-old Bengal cat owned by Tom and Barbara Eshom. Tica’s owners noticed a very firm, raised mass in her skin. As with Bruno and Sadie, a fine needle aspirate was performed, but after looking at the sample, Dr. Smith decided to have a pathologist review the slide as well. The pathologist reported seeing mostly inflammation, but cancer could not be ruled out.

Because of the chance of cancer, Tica underwent surgery to have the mass removed. This proved to be a good decision. When the entire mass was submitted to the pathologist, he could give a more specific diagnosis. Unfortunately, it turned out Tica did have a cancerous tumor called a fibrosarcoma. Luckily, these tumors are slow to metastasize; however, they can be aggressive and have a chance of recurrence. Now that Tica’s owners know exactly what we are dealing with, they know the signs they need to watch for in Tica and can consider consulting an oncologist.

Always Have Lumps Diagnosed by Your Veterinarian

As you can see, from the stories of Sadie, Bruno and Tica, it is important to have any new “lump” examined. A fine needle aspirate is usually needed to make a diagnosis and treatment plan. Remember, some masses are benign and do not require treatment, but if surgery or other treatment is needed, you increase your pet’s odds of having a good outcome by arriving at a diagnosis as early as possible.