What is Pancreatic Cancer in Dogs?
Pancreatic cancer in dogs is a tumor that develops due to the abnormal growth of cells in the dog’s pancreas.
The pancreas is a vital organ located near the start of the small intestines. The pancreas has two types of cells grouped according to their function: endocrine cells and exocrine cells.
The exocrine cells produce digestive enzymes that help with food breakdown in the gut. The endocrine cells produce hormones (insulin and glucagon) that regulate some body processes.
Pancreatic cancer in dogs is rare, but when it occurs, it is very aggressive due to its high rate of metastasis. Pancreatic neoplasms tend to spread to other tissues and organs such as the regional lymph nodes, liver, small intestines, bones, and lungs.
Types of Pancreatic Cancer in Dogs
There are different types of pancreatic cancer in dogs. Some pancreatic tumors are benign, and others are malignant.
The most common benign pancreatic tumor is the adenoma, while adenocarcinomas and insulinomas are the two most common malignant types of pancreatic cancer. Since malignant pancreatic tumors are more common, let’s take a closer look at them.
Adenocarcinomas. Adenocarcinoma, also known as exocrine pancreatic carcinoma, is a type of cancer that starts in the exocrine cells of the pancreas. Adenocarcinoma is very rare but aggressive. Pancreatic adenocarcinomas cause damage to the pancreatic cells resulting in reduced secretion of digestive enzymes (for example, lipase).
Insulinomas. This type of pancreatic cancer starts in the insulin-producing cells of the pancreas. Insulin is an essential hormone that controls glucose (blood sugar) levels. Without insulin, blood sugar would shoot up after meals to life-threatening levels (similar to what occurs in dogs with diabetes mellitus). Too much insulin causes hypoglycemia which is also dangerous.
Is Pancreatic Tumors in Dogs Painful?
Yes, pancreatic cancer in dogs can be excruciating, especially in the later stages. Benign pancreatic tumors are less likely to cause pain, but they are sporadic in dogs.
Malignant pancreatic tumors, on the other hand, often cause pain. Even if the tumor is not painful on its own, its secondary effects can cause pain.
For example, pancreatic cancer can spread to the bones and cause pain in the limbs during movement. Fluid buildup in the pancreas or liver can cause abdominal pain.
What Causes Pancreatic Adenocarcinoma in Dogs?
The exact cause of pancreatic cancer or any type of cancer is hard to determine. Most cancers are triggered by a combination of environmental and genetic factors. Here is a look a the factors that seem to play a role in the development of pancreatic cancer in dogs:
- Genetics. Pancreatic cancer in dogs is more common in certain breeds. For example, adenocarcinomas are prevalent in Airedale Terriers, while insulinomas are more commonly seen in breeds such as Boxers, Irish Setters, Fox Terriers, German Shepherds, Labradors, and Golden Retrievers.
- Environment & Lifestyle. Exposure to carcinogens increases the dog’s risk of developing cancer. So does its lifestyle – diet, exercise regimen, and body weight.
- Age. Age also plays a significant role in a dog’s risk for pancreatic cancer. It is more common in dogs over 11 years of age.
- Diabetes Mellitus. According to VCA Hospitals, cats with diabetes mellitus are at higher risk of developing pancreatic cancer than healthy cats. This connection is not proven in dogs, but it is worth considering.
What are the Symptoms of Pancreatic Cancer in Dogs?
The clinical signs of pancreatic cancer depend on the type. High insulin levels and very low blood sugar levels (hypoglycemia) are often seen in insulinomas. In such cases, dogs show:
- Lethargy and overall weakness
- Twitches, tremors, and seizures
- Sudden collapse.
For adenocarcinomas, the signs and symptoms are nonspecific until the later stages when pancreatitis (inflammation of the pancreas) becomes severe. The signs include:
- Fluid build-up and distended belly
- Anorexia (complete loss of appetite)
- Pronounced weight loss
- Severe abdominal pain.
As pancreatic cancer in dogs spreads, abnormalities may occur in other organs; for example:
- Lameness (bone metastasis)
- Difficulty breathing (lung metastasis)
- Jaundice (bile duct and liver metastasis).
If your dog is showing some of these symptoms, call the vet and book an appointment. The sooner you catch the disease, the better the outcome.
Diagnosing Pancreatic Adenocarcinoma in Dogs
The diagnosis of pancreatic cancer in dogs starts with a thorough physical examination. If the vet suspects pancreatic cancer, they will order blood tests to check for signs of damage to the pancreas, such as low blood sugar levels and high insulin levels.
The vet may also perform an ultrasound-guided fine-needle aspiration or biopsy where they collect cells from the pancreas. In both cases, the collected sample is analyzed under a microscope (in veterinary medicine, this is called either cytology or histology, depending on the type of sample).
If these tests show cancerous cells and the diagnosis is confirmed, the vet will order additional tests for tumor staging and evaluating the dog’s overall health. Such tests include urinalysis, blood work, chest x-rays or radiographs, abdominal ultrasounds, and CT scans.
How do You Treat Pancreatic Cancer in Dogs?
Pancreatic cancer in dogs treatment depends on the tumor type and stage. In general, the best treatment for pancreatic cancer is surgery. Radiation and chemotherapy can also be added to the treatment regimen.
Surgery. For insulinomas, partial removal of the pancreas (partial pancreatectomy) may be performed to remove the pancreatic mass. Some dogs with adenocarcinomas qualify for a similar procedure, but it is more aggressive as the whole pancreas (total pancreatectomy), and portions of the stomach and the duodenum (start of the small intestines) may have to be removed.
Chemotherapy and Radiation. Chemotherapy and radiation therapy are possible. However, so far, they do not show great promise as treatment options for pancreatic cancer.
As a dog owner, your role is to make your dog as comfortable as possible. Ask your vet what holistic options are best for your dog. Available options include diet, pet CBD supplements, acupuncture, physiotherapy, and herbs.
Diet. The right diet is vital for dogs with pancreatic cancer, especially those with insulinoma (they need frequent meals to maintain steady blood sugar levels). Small meals may be more suitable for dogs with adenocarcinoma, as their digestive function is compromised. It is best to see a veterinary nutritionist for a diet plan for your dog.
What can I do to Prevent Pancreatic Adenocarcinoma in Dogs?
The question of how to prevent cancer in dogs has no definitive answer. You can lower the risk of pancreatic cancer in dogs by providing a healthy diet, regular physical exercise, using pet-safe products, and protecting their mental well-being.
In the event your dog develops pancreatic cancer, providing the best treatment is important. The expenses of cancer treatment add up quickly (for example, partial pancreatectomy can cost up to $6000).
Is Pancreatic Cancer in Dogs Treatable?
Yes, pancreatic cancer in dogs is manageable, but only if caught early and treated promptly. In practice, the disease has a very poor prognosis because it has usually already metastasized at the time of diagnosis.
For advanced cases of pancreatic cancer in dogs, surgery followed by chemotherapy is the best treatment. Sadly, not all dogs with pancreatic cancer are good surgical candidates.