Skin growths are lumps of tissue that are within the skin or can be felt under the skin. Cats can develop small bumps or larger bumps on their skin. These lumps and bumps are fairly common occurrences, especially in the older cat. Very often the word "lump" brings the word "cancer" to mind. However, there are many other causes of lumps. A skin growth or mass may be a malignant or benign tumor, an abscess, a cyst, a hematoma (blood-filled mass) or a reaction by the skin to an allergen (hives). Lumps are often benign accumulations of fat called lipomas. However, all lumps should be evaluated for the possibility of malignancy.
For more information, please read
Skin Growth, Lump, Swelling or Mass.