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13 Signs Your Chihuahua May Have Cancer

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13-signs-your-chihuahua-may-have-cancerI remember sitting in my home office and watching my fluffy white terri-poo Joey stand up. The little lump that I had felt on his back leg a few days prior was suddenly huge! How did that happen in just a few days?

What was even worse was that there was some spots of blood on his dog bed. I checked the lump and it had cracked open. I’m not sure if Joey had been scratching at it or it just opened because it had grown so big so fast, but there was a foul odor coming from it.

I immediately got him in to see my vet who suspected  cancer. Even if it wasn’t cancer, it needed to be removed as quickly as possible to avoid  infection so he was operated on the next day.

Turns out it was cancerous and a fast growing kind. Fortunately though, it was isolated and hadn’t gone to any other organs so he didn’t need radiation or chemotherapy.

Joey was 13 when this happened and despite the warning from my vet that it would probably come back, it never did. He lived almost another 6 years.

Cancer can strike almost any animal, and our pets are no exception. Like many diseases, cancer is more common in older animals, but can affect pets of any age. So, without getting alarmist or paranoid about it, you want to be on the alert for possible signs of trouble.

According to Cancer Vet Centers, the 5 most common type of cancers that dogs get are: 

  • Bone Cancer also known as Osteosarcoma
  • Hemangiosarcoma
  • Lymphoma
  • Mast Cell Tumors
  • Melanoma

Of course they can get other kinds of cancer but those are the most common types.

The possible warning signs of cancer in chihuahuas are about the same as for any dog, and can also be potential indicators of a wide array of other health problems.

Only your veterinarian can determine for sure. By all means, if you spot one of these signs, have your vet check it out. It might mean nothing more than a minor issue, and knowing that would contribute a lot to your peace of mind!

Look out for these signs, especially in chihuahuas over the age of 10:

Lumps or swellings that persist for more than a short period of time
Sores, especially with bleeding or discharge
• Unexplained weight loss (or gain)
• Loss of appetite
• Apparent difficulties with eating or swallowing
Lethargy and lack of stamina
Unusual odors (although remember, chihuahuas are prone to bad breath and dental issues)
• Unexplained lameness
• Indications that the dog is uncomfortable in certain physical positions
• Digestive symptoms such as vomiting and diarrhea
• Changes in elimination habits
Respiratory difficulties
Odd behavioral changes

Can cancer in dogs be prevented?

Not always, and not consistently. Of course, a well-cared-for dog such as yours will present fewer health problems generally, but cancer does not always respect your best efforts. While the incidence of certain cancers such as ovarian, breast, and testicular cancers can be nearly eliminated by early spaying and neutering, those operations may actually increase the risk of of other forms of cancer.

Are all dog tumors malignant?

Certainly not – no more so than in humans. Your vet can advise you on the best way to deal with benign growths.

Can dog cancers be treated?

Often, yes. Admittedly, treatment is not guaranteed of success, and can be expensive. But it is often worth a try. A good veterinarian will present you with the full range of options from the least to most aggressive and the least to most costly.

Although sometimes there is no avoiding the worst scenario, in many instances it is worth fighting for our chihuahuas. If we can gain them more years of life with no significant loss of quality, both we and the dogs are winners.

Cathy signature Chi

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Saturday 6th of March 2021

I just noticed yesterday a large mass on my Daisy-bell a deer chihuahua, on her right side ribs. I am fearful The mass is not good. I can touch with no pain. Daisy-bell shows no pain. She is around 13 years old. I'm not sure of her age, she was a lost dog before I found her. Thanks Tina


Saturday 6th of March 2021

Definitely get that checked out by a vet. It doesn't have to be painful to be cancer.

Linda lindsey

Friday 25th of December 2020

are teacup chihuahuas more prone to tumors in intestines


Friday 25th of December 2020

I haven't heard they were more prone to that in particular but they are more prone to health problems so it wouldn't surprise me.


Wednesday 4th of November 2020

Just found out my chi has breast cancer. Doc is suggesting to she undergo a mastectomy and to have her spayed her. Is this necessary? Can't they simply cut out the tumor? They say the mastectomy and spaying her lowers her chances of cancer in the future. Of course it does! She can't get cancer in an organ she no longer has! Any suggestions?


Wednesday 4th of November 2020

I'm not a vet so I can only give my opinion but I would have her spayed too. Your vet is right and she already has cancer. Having her uterus intact will give her a higher chance of other cancers too. You can always get a second opinion if you are really questioning this but if she were my dog, I would do both.

Carol Love

Friday 25th of September 2020

Why does my chiwawa sleep with his butt in the air


Friday 25th of September 2020

I've seen children sleep like that but not dogs so I'm not sure. Probably just a weird chi thing.

Christine Thiel

Thursday 6th of August 2020

My deer head male chihuahua was only a year old when when the vet found blood in his stomach and during surgery for he had cancer .. is that a common thing with male chihuahuas?


Thursday 6th of August 2020

No that's not normal Christine, specially in a dog so young. I'm so sorry you (and he) are going through this.