Does your dog have a lump or bump on or under their skin? While lumps and bumps are more common in older dogs, younger dogs can get them too. 1 Most lumps and bumps are benign (non-cancerous), but some of them can be malignant (cancerous). The older your dog is, the higher their chance of getting malignant lumps. The good news is that early detection and treatment of cancerous lumps can increase the chances of a cure. 2
What type of lump or bump is more dangerous? What causes lumps and bumps on dogs, and how can you treat them?
How your vet can tell what type of lump or bump your dog has
Your vet will conduct one or more of the following tests to determine the type of lump or bump your dog has and the treatment required 2 :
Fine needle aspiration (FNA) – Firstly, your vet will determine if this procedure can be performed during the consultation without the use of sedatives. If the vet determines they can use this technique for a diagnosis, a small needle is inserted into the lump to suck out cells which are then deposited onto a slide. Next, the slide is stained and the slide is viewed under a microscope to examine the cells. Your vet may send the slide to a specialist (pathologist) in a laboratory for examination. About 95% of lumps and bumps can be diagnosed via FNA. 2
Impression smear – If the lump discharges fluid, your vet may rub a slide onto the lump, and then stain it and examine the fluid as with an FNA.
Biopsy – If the FNA isn’t diagnostic or only contains blood/fluid, your vet might take a biopsy of the lump. Generally, your dog will receive a sedative or anaesthetic and a small part of the lump or the entire lump will be removed. Then the lump is placed in formalin and sent to a lab, where thin sections of the lump are examined under a microscope.
Lab test – If the lump contains fluid, the fluid could be sent to a lab to culture and check for infectious agents like fungi or bacteria.