Neoplasia is a term used when a mass of cells has grown abnormally and quickly, but it doesn’t always mean cancer. It’s common for pet parents to panic a little when they hear the word, but just because your pampered pooch or cherished cat has a neoplasm (the mass itself), it could just as easily be benign as cancerous.

Allow me to explain...

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  1. How Do Neoplasms Arise
  2. What Are the Symptoms of Neoplasia in Pets
  3. General Types of Neoplasia
  4. Where Could Neoplasms Occur
  5. How Does a Vet Diagnose Neoplasia in Pets
  6. How Can the Emergency Fund Help with Treatment
  7. Conclusion

How Do Neoplasms Arise

According to the American Veterinary Medical Association research, one in four dogs will experience neoplasia at some point in their lives. Not all cases of neoplasia are malignant (cancerous), but it is estimated that fifty percent of all dogs aged ten or older will develop some form of malignant neoplasia.

Neoplastic diseases are not yet fully understood, so the direct causes of neoplasms (tumors or masses) aren’t known. Neutering or spaying reduces the risk of certain cancer types in both cats and dogs, specifically testicular and mammary cancers.

What Are the Symptoms of Neoplasia in Pets

Symptoms of neoplasia in pets will heavily depend on the type of neoplasm, where it is, what it’s close to, and underlying medical issues. In many cases, internal or difficult-to-see masses are more likely to go undetected for longer, but even external lumps and bumps can develop without other obvious symptoms. Regular monitoring of pets with Pet Camera and other pet tech devices will help you pick up early symptoms.

It's recommended to seek veterinary advice if your pet displays any of the following symptoms, which could be a sign of both benign and malignant neoplasia:

  • Swelling of the abdomen;
  • Breathing difficulty or changes;
  • Nose, mouth, or other orifice bleeding;
  • Visible neoplasms (masses);
  • Obvious signs of pain or discomfort from your pet;
  • Weight loss or gain;
  • Vomiting, diarrhea, regurgitating, or retching that doesn’t go away;
  • No interest in food or water;
  • Struggling to eat, drink, or swallow;
  • Skin changes (color, rashes, bumps, etc.);
  • Wounds that won’t heal.

General Types of Neoplasia

If your pet has been diagnosed with neoplasia, the masses or tumors can be:

  • Benign – non-cancerous;
  • Malignant – cancerous.

Malignant neoplasms have the potential to be deadly if not treated, with cancer growing at an unpredictable rate and spreading to other organs and parts of the body. The spread is known as metastatic neoplasia in dogs, cats, or other animals, including humans.

Benign masses also have the potential to be life-threatening if they interfere with organs or other parts of the body. A benign tumor close to the stomach could quickly cause a squash-caused blockage, leading to vomiting, regurgitation, severe weight loss, malnutrition, dehydration, and much more. Non-cancerous tumors also tend to be slower-growing than their cancerous counterparts, and they don’t spread.

Where Could Neoplasms Occur

The most common type of neoplasia in dogs is adenocarcinoma, which is a type of cancer that affects the large intestinal and gastric systems. The MSD Veterinary Manual also states that the most common type of malignant neoplasia in cats is lymphoma (lymph nodes), with adenocarcinoma holding the number two spot. Other types of gastrointestinal tract cancer include GIST (gastrointestinal stromal tumors).

Neoplasms can also occur in the following places in both cats and dogs:

  • Skin: melanoma, squamous cell carcinoma, mast cell tumors, and benign fatty tumors (lipomas);
  • Respiratory-nasal tumors are common in cats; primary lung tumors and bronchial carcinomas are common in dogs;
  • Lungs;
  • Mammary glands — the pet equivalent of breast cancer;
  • Liver;
  • Bone marrow;
  • Bladder;
  • Bone osteosarcoma is common in large dogs and cats; the latter also commonly develop chondrosarcoma and fibrosarcoma;
  • Reproductive organs, such as testicular neoplasia in male dogs;
  • Spleen.

How Does a Vet Diagnose Neoplasia in Pets

The most common way to diagnose a neoplasm in cats, dogs, humans, and other animals is to have a biopsy performed. This removes a piece of the mass, allowing it to be tested in a laboratory. Depending on where the mass is, this can be done either under general or local anesthesia. An alternative to a biopsy is FNA (fine needle aspiration), which is quicker and easier and often doesn’t require anesthetic or sedation.

Before any tests are done, your vet will perform a complete physical examination while asking routine questions about what you, the pet parent, have noticed in terms of symptoms. Medical history is also important. Pets that have already had cancer are more likely to develop it again.

Your vet may also recommend X-rays, CT and/or PET scans, MRIs, endoscopies, other forms of exploratory surgery, or ultrasounds alongside blood and urine samples.

How Can the Emergency Fund Help with Treatment

Cancer is an emergency in the pet world (and in the human one), which is just what the Emergency Fund by Petcube caters to. For under $1 per day, you’ll have access to an array of features that will become your new BFF in frightening pet situations. These include 24/7 vet contact, up to $3,000 of emergency care, coverage for up to six pets in your household, and peace of mind when you need it the most.


Although the term neoplasia sounds scary, it doesn’t always mean malignancy. Unfortunately, without proper diagnostic testing and examinations, you and your vet won’t be able to determine whether the uncontrollable growth of cells is benign or malignant.

As with all pet symptoms that are new or concerning, seek medical advice from a licensed vet as soon as you notice lumps, bumps, or masses or spot something unusual. The only way to get the problem resolved is to find out what it is and then effectively treat it.

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