Cats have many types of lumps and bumps on their skin. Skin tags have several names including fibropapillomas, polyps or acrochordons. Most times these growths are benign, meaning they are not malignant or cancerous.
Some swelling on your cat's skin is because of fluid or damage under the skin. A pus-filled lump is a pustule. An injury, fungal infection or foreign body under the skin can cause a lump.
Papules are elevated lesions that are shiny and may have a tiny pit or depression in the centre. They can be malignant or benign.
Martin Slome, DVM, Centre Street Animal Hospital in Ontario, Canada, notes that there are many types of benign growths including sebaceous cysts, warts and hair-follicle cysts. Mark Thompson, DVM, a writer for Petplace.com, states that most lumps are benign fat collections called lipomas.
Mast and basal cell tumours and melanomas are cancers that may look similar to a skin tag when they begin growing. Mast cells look like raised pink lumps. Basal cells are typically firm and clearly defined borders. Melanomas lumps may be black or same pigment as the skin.
Because lumps on your cat may look similar, it is best to have your veterinarian determine what the lump is. If she determines it is a skin tag, unless it is infected, it does not need to be removed. Thompson recommends that any new lump or one that starts growing, bleeds, causes pain or seems infected should be evaluated by your vet. Often a veterinarian will remove the lump if there is any doubt about it.