You’re sitting on the couch, watching TV and petting your beloved furry friend when you feel it… a lump! Should you have it checked out or just ignore it? I’m here to tell you that you should always have any lump, bump, growth, or mass checked by your veterinarian. It’s important to document the characteristics of the growth including size, shape, color, and location so that any changes in these characteristics can be monitored. To help diagnose a mass, the first step is often an FNA or “fine needle aspirate”. This procedure involves taking a sterile needle, inserting it into the mass to collect some cells, and then placing these cells on a slide. We stain the slide and then look at the cells under the microscope to try and figure out the origin of the mass. Some masses don’t exfoliate well, meaning it is hard to collect cells on FNA and therefore we are unable to diagnose the mass. In these cases, we may recommend biopsying a piece of the mass or completely removing the mass via surgery and then sending it to a pathologist for biopsy.
It’s important to classify the mass, either via FNA or biopsy, so we know how to proceed with treatment. For example, skin tags, sebaceous cysts, and lipomas are all examples of benign lesions that do not necessarily require any intervention. Surgical removal of benign lesions is cosmetic, or recommended if the lump bothers the pet (i.e. it is bleeding, becomes infected, is located on the body in an area that affects mobility, or causes pain and discomfort). If a mass is malignant this means it is cancerous and likely to spread to other parts of the body. Some examples of malignant neoplasms include mast cell tumors, melanoma, and squamous cell carcinoma to name a few. The treatment depends on the biologic behavior of the tumor. Some cancers are curative with complete surgical removal of the mass while others require radiation and chemotherapy treatment.
In summary, we cannot diagnose a lump or bump simply by looking at it with our eyes. There are a number of potential diagnoses for a lump and having it evaluated is very important in establishing a treatment plan. Not all masses are the same so the next time you’re relaxing with your pet on the couch and feel a lump, tell your veterinarian!