How to Tell if a Lump on a Dog is Cancerous

by Sarah


Unfortunately, there is no way of knowing just by looking at or feeling a dog lump if it is cancerous or not. You should become acutely aware of your dog’s body so that you are able to notice changes when and if they occur. A good rule of thumb is that if the lump or bump is still there after 3-5 days, get your dog to the vet to be evaluated.

However, don’t be too quick to panic that the worst is inevitable just yet. There are plenty of other benign (non cancerous) lumps and bumps out there. Some of these include:

Fatty Lumps: The technical term for these is “lipomas.” The majority of these are scene in more obese dogs and may need to be removed as they could grow over time; but they will not spread to other parts of the body the way that cancer does.

Sebaceous Cysts: Yep, these are kind of like zits that human get (poor Fido isn’t immune). These do tend to happen more often in older dogs. The cysts contain a puss-like substance that has the consistency of toothpaste. They can become swollen and red looking but will not cause harm to your dog.

Histiocytoma: These are currently seen in younger dogs, appear fast, and go away just as quickly. They resemble buttons and may be very red and they are about 1 cm in diameter. These rarely need any type of treatment.

Warts: Nope, dogs are not immune to these ugly skin tags. Treatment is not usually required unless they become irritated and bleed. A dog may develop many of them.

A Couple Signs That Might Indicate Dog Cancer

1. If the lump is not easily moved around, it could be malignant as cancer often grows into the tissue around it, making the tumor nearly immoveable.

2. If your dog has a lump or bump as well as unexplained weight loss, decrease in appetite and energy, or diarrhea and vomiting this could signal something serious.

3. If the lump or bump or the area around it bleeds, has discharge, is extremely irritated and is painful, it may be malignant.

The above are not hard and fast rules to determine whether or not a lump is malignant or benign. Even your vet can’t know exactly what it is just by looking at it. If the lump is suspicious, your vet will need to take a small piece of it and send it off to examine the cells (this is called a biopsy).

I found a really informative 5-minute video on this exact topic if you want to check it out below. And as always, don’t risk your dog’s health. Get to your vet whenever something out of the ordinary occurs!

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