What does dog cancer look like? Are pea-sized lumps a big deal? Short answer: yes. This doesn’t mean there is a need to panic. Instead, it means you should make an appointment with your veterinarian for a potential aspiration of the lump (using a fine needle to gather a small amount of cells to be examined under a microscope). There is a good possibility it’s benign (non-cancerous), but it’s better to be safe than sorry.
When pea-sized lumps are found to be cancerous, there are many times where it has not had the opportunity to spread to other parts of the body. If you wait, and it is cancer, your dog will be more at risk of metastasis (cancer spread). This is what we want to prevent.
We know it’s extremely difficult to even think about your dog having cancer, but knowing if the tumor is benign or malignant is crucial, both for your dog’s well-being and your own. If the pea-sized lump grows, and it is cancer, many pet parents will blame themselves for not getting into the veterinarian sooner.
Causes of a Pea Sized Lump on Dogs
There are several potential causes for pea-sized lumps on your dog, including:
Fatty Tumors (Lipoma)
Lipomas are benign fat tumors that can appear anywhere on the dog’s body. These lumps are usually round and soft to the touch, although in some cases they may have a pea-sized diameter. They typically occur around the neck, armpits, groin area, or along a hairline.
Fatty tumors can be caused by a number of factors including heredity and diet. If your dog has one of these growths removed from its body it will not grow back again because it is not cancerous; however, there is no way to stop them from appearing in the future if you haven’t already taken steps to prevent this from happening before now (such as changing your pet’s diet).
Sebaceous cysts are the most common type of lump on dogs and are caused by an accumulation of oil and dead skin cells. This is a very common condition in dogs with long hair, especially those who have been groomed recently. They’re usually painless, but may be uncomfortable. If left untreated, some cysts will become redder or larger over time and could burst open. If that happens, your dog could develop an infection that requires medical attention.
If you think your dog has a sebaceous cyst:
- Take him to the vet so he can check it out and see if treatment is needed. Your vet might recommend surgery if there’s no obvious cause for the lump (like an insect bite).
- Keep your pup clean; regular baths with soap will help prevent irritation from dirt buildup around the lump
Hair Follicle Cysts (Epidermal Inclusion Cysts)
The cause of a pea-sized lump on dogs, is an epidermal inclusion cysts. These are typically benign and are caused by a small hair follicle that has become trapped in the skin. These cysts can occur anywhere on the body, but more often than not they appear around the mouth, nose and lips.
There are several things to keep in mind about epidermal inclusion cysts (also known as comedones):
- They’re usually not painful
- They’re generally painless unless they become infected or inflamed
Papillomas (Viral Warts)
Papillomas are warts caused by the papilloma virus. They usually appear on the tongue, lips, or nose, and can be removed by a veterinarian. They’re not harmful to your dog and will go away on their own within three months if you don’t remove them yourself.
Calcinosis Cutis (Dermal Calcium Deposits)
If your dog has a pea-sized lump on their body, it might be a calcium deposit. Calcinosis cutis is rare and can be caused by a number of things, including hyperparathyroidism (a disease that affects the thyroid gland), kidney disease or malignancy. I
t’s not painful for your pet—and it won’t hurt them unless you forget about it and try to remove the calcium deposit yourself! If you notice this condition on your dog’s skin, bring them in to see the vet right away so they can rule out more serious underlying causes.
What if it’s Benign?
If the pea-sized mass is benign, AKA non-cancerous, your veterinarian will likely still want to examine the lump on occasion. You should monitor the mass to see if it has grown. Benign tumors are removed surgically only when necessary.
If the mass is impeding on organs or affecting mobility, that’s when it will become a concern. On a positive note, knowing the mass is benign can put your mind at ease. Remember, your dog can feel your emotions and reflects upon those emotions. If you’re calm, your dog is more likely to be calm. Likewise, if you’re worried, your dog may show signs of distress and/or become destructive.
What if it’s Cancer?
If it’s cancer, a pea-sized lump is much easier to remove than a large mass. It’s also much easier to get clean margins when the mass is small because the cancer has likely not spread to other parts of the body. Your dog’s prognosis is often much better when the cancer is caught early.
Since it is more difficult to get rid of all the cancer once the mass has grown, your dog may require chemotherapy, radiation, and surgery, among other treatment modalities to get rid of the cancer if you wait. Whereas, if the lump is removed when it’s small, other modalities are often not recommended.
Get a Biopsy for a Pea Sized Lump
Whenever you see any kind of mass, it’s important to schedule an appointment with your veterinarian. If your veterinarian refuses to aspirate the lump, look for a veterinarian who will aspirate to determine if the mass is benign or malignant. This will save you a lot of time, money, and heartache down the road should the lump be cancerous.
Watch Dr. Sue, the Cancer Vet, discuss fine-needle aspiration below in just over 60 seconds:
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