Dogs and cats may develop lumps or abnormal growths. Not all growths are worrisome, but they all need attention to identify what is going on. Lumps and bumps may be due to a reaction, infection, or inflammation, but they also may be overgrowth of abnormal tissue. It could be a combination of inflammation and abnormal tissue growth. This overgrowth may be benign (inert, non-harmful) or malignant (cancerous growth). A malignant growth may spread throughout the body or be locally invasive.
When lumps are discovered, the first step is to have it evaluated. The veterinarian will evaluate the location, what it looks and feels like, and the size. Based on the exam, the doctor will decide if diagnostics and treatment are necessary. If the growth appears to be due to inflammation, treatment may be different than if it appears to be abnormal tissue development. Some or more of the following treatment and diagnostic options may be necessary.
Some treatment and diagnostic options may include:
- Medications to treat inflammation or infection
- Injections to address inflammation
- Sample collection (aspirate) and cytology (laboratory evaluation)
- Surgical removal & histopathology (laboratory evaluation)
Unfortunately, the veterinarian cannot tell what a growth is without diagnostics. Some growths may feel benign but may be malignant. Diagnostics are the only way to know for sure if the lump is inflammatory, benign, or malignant or a combination.
Cytology is usually the first laboratory test that is run. A small sample of the cells is drawn out with a needle and placed on a microscope side. The slide is sent to a laboratory where the cells are evaluated by a pathologist to identify if the lump is infectious, inflammatory, benign tissue, or malignant tissue. Based on those results, further treatment protocols are recommended. Additional treatments may include medications, x-rays to look for spread, and/or surgical removal.
If surgery is required, the lump is removed with at least 1" around it on all sides. This is the recommended margin allowance. By removing such a large area, we improve the chances that the abnormal tissue is completely removed. Further laboratory evaluation (histopath) confirms that the entire lump was removed. Unfortunately, due to the requirement of needing large margins, incision sites where lumps are surgically removed tend to be significantly larger than the lump itself. In areas on the legs or tail or other locations on the body, there may not be enough skin tissue to allow for appropriate margins. This increases the risk of incomplete removal. Because of this, we recommend removing concerning lumps before they get very large.
Lumps and bumps can change over time. On occasion, some growths that start out as benign, can develop more abnormal growth that needs to be removed. Any changes to the area need to be noted to the veterinarian and diagnostics may need to be performed on the same lump multiple times.
Pets with multiple lumps may need to schedule a drop off for tumor mapping. Tumor mapping is a thorough exam of the entire body where every lump and bump is identified, measured, and described in appearance, size, and feel. This complete evaluation of more than two lumps at a time is a time consuming task which cannot take place during a normally scheduled appointment. Any lumps that have not previously been identified or those that may have changed or give the veterinarian cause for concern may need to be sampled and submitted to the lab.
If your pet has a lump, bump, or growth you are concerned about, schedule an appointment with us today.