"Tumors"

What is that Lump and What does it Mean?

Pets, like humans are prone to growths or lumps on their bodies, especially as they age. It is important to identify any persistent lump that has been there at least two weeks, especially if it is 1) growing 2) changing in consistency or character 3) bothering your pet. The growths may be noncancerous or cancerous and those that are cancerous may be benign or malignant. Cancer is a indication of uncontrolled growth. Benign means that the cancer tends to be localized to the one area and does not usually spread to other areas, whereas malignant tumors have a increased likelihood of spread to other organs.

There are several ways to identify what a lump is. The size and consistency give us clues as to what it might be, but certainly is not definitive. With a fine needle aspirate, a small needle is introduced into the site and some of the cells are collected and sprayed onto a microscope slide. The slide is then read in-house or sent to a veterinary pathologist for a diagnosis. If a lump is severely inflamed or infected, a diagnosis may not be reached. With a biopsy, an actual piece or the entire lump is excised and sent off to be read by a pathologist. This is a more definitive way to identify the cause of a lump and gives your veterinarian a better idea of the margins, aggressiveness and whether it is benign or malignant. Certain types of tumors, such as mast cell tumors or soft tissue sarcomas require wide field excision, so it is beneficial to know what type of tumor a lump is before a definitive surgery. In some cases, it is necessary to revise the surgical margins to remove all of the tumor tissue.

Once a lump has been identified, the next course of action can be determined. Some benign tumors do not need to be excised if they are not bothering the patient and are staying the same size. Others should be excised. In most benign tumors, surgery is curative and once the sutures are removed, nothing else needs to be done. However, in other cases further tests such as x-rays, ultrasound or lymph node biopsies should be done to further stage the cancer. It is important to note that although a pet may have multiple lumps, they are not necessarily of the same type, and each one should be tested individually. As a rule of thumb, any lump that is present greater than 2 weeks should be seen as well as any that are growing quickly or fluctuate in size. Growths in the mouth, on the feet, and in the mammary glands are particularly worrisome and should be seen as soon as you notice them. Your veterinarian will be the best judge of what the next step should be.