Pancreatic Cancer in Cats

Pancreatic tumors are relatively rare in cats and can be either malignant or benign. Unfortunately, cats with pancreatic tumors rarely show signs until the disease is quite advanced and symptoms tend to mimic other diseases. The two main types of pancreatic tumors in cats are pancreatic adenomas and pancreatic adenocarcinomas. If the tumor is benign, it’s called a pancreatic adenoma. When malignant (cancerous) the tumor is called a pancreatic adenocarcinoma. Unfortunately, most primary pancreatic tumors are malignant. There are occasionally pancreatic tumors that do not originate in the pancreas, but are secondary tumors that stem from a tumor that originated elsewhere in the cat’s body and then spread to the pancreas. Lymphoma is a prime example of a secondary tumor affecting the feline pancreas.

Malignant pancreatic tumors tend to be very rare and usually occur in senior cats (usually over 8 years old with a median age of 12 years ¹). Adenocarcinomas arise from the glandular cells of the pancreas and tend to be very aggressive, spreading rapidly to other parts of the body. The exact cause of pancreatic cancer is idiopathic (unknown).

Regarding Pancreatic Adenomas

Pancreatic adenomas are benign (non-cancerous) tumors that usually do not require treatment. In situations where the tumor is causing symptoms, treatment, usually surgery, may be considered. The prognosis for cats with a non-cancerous pancreatic tumor (adenoma) is often excellent. The remainder of this article will focus on pancreatic adenocarcinoma, which is a cancerous pancreatic tumor.

Signs and Symptoms of Pancreatic Cancer in Cats

Feline pancreatic cancer can be difficult to diagnose because the symptoms are usually non-descript and by the time a cat presents with symptoms, the cancer is usually at an advanced stage. When a cat displays signs of pancreatic cancer, symptoms may include:

• Weight loss
• Loss of appetite
• Nausea/vomiting
• Abdominal pain
• Jaundice (yellowing of the eyes and skin)
• Increased thirst and urination
• Fever
• Lethargy
• Diarrhea

As you can see from the list, many of these symptoms could be attributed to a whole host of other issues or diseases. For this reason, diagnosing a cat with pancreatic cancer is often very difficult.

Diagnosing Pancreatic Cancer in Cats

Diagnosing pancreatic cancer in cats can be tricky and requires a combination of various diagnostic methods. Although cats with pancreatic cancer may exhibit abnormalities on blood tests and imaging, these findings can be similar to those of other diseases. To confirm if your cat has pancreatic cancer, your veterinarian will need to perform a biopsy or cytological exam. Other diagnostic tests are typically performed to determine the cause of your cat’s symptoms. Diagnostics include:

A Physical Examination

A thorough physical examination, including palpation of the abdomen, may help identify any abnormalities or masses.

Blood Work-Up & Urinalysis

Blood work including a complete blood count (CBC) and a chemistry profile are a great starting point. Additionally, your veterinarian will take a closer look at the amylase and lipase enzymes which are enzymes released by the pancreas. Lipase and amylase levels are often elevated in a majority of feline patients with pancreatic adenocarcinoma. A urinalysis will further aid in evaluation of the patient.

Imaging Tests

Abdominal X-rays are often the first imaging test performed though ultimately, an abdominal ultrasound is needed to further assess the pancreas, surrounding organs and the abdominal lymph nodes. Advanced imaging procedures such as CT scans can help visualize the pancreas in a much more detailed way, detect tumors, evaluate their size and any potential spread. A CT scan can also help determine the feasibility (and approach) of surgery.

Biopsy or Cytological Exam

A biopsy is the definitive method to confirm pancreatic cancer. It involves obtaining a piece of tissue from the pancreas that is examined under a microscope. Sometimes a less invasive procedure is performed called a cytological exam. This involves examining cells from a sample obtained through an ultrasound-guided fine-needle aspiration (FNA).

Staging of Pancreatic Cancer in Cats

After confirming the diagnosis, the stage of the tumor needs to be determined to understand the extent to which the cancer has spread. Knowing this will help in determining the available treatment options and the most appropriate course of treatment. Staging includes three-view chest x-rays to assess for any spread to the lungs as well as the abdominal ultrasound or CT to assess whether the cancer has spread to other organs such as the liver or the lymph nodes.

Treatment Options for Cats With Pancreatic Cancer

Unfortunately, no treatment is considered curative when it comes to pancreatic cancer in cats. Therefore, a primary goal of treatment is to provide as much comfort and quality of life as possible while addressing any underlying issues and symptoms associated with the disease. Treatment options vary depending on the type and stage of cancer and can be challenging due to its aggressive nature. The primary objective is to enhance the quality of life of the cat, mitigate symptoms, and decelerate the cancer’s advancement. Treatment options may include:

Surgery

Surgical removal of the tumor is considered the most effective treatment when feasible. In some cases, it is possible to remove the part of the pancreas that contains the mass. Other times, the entire pancreas may be affected in which case, surgery is not advised. When there is an advanced stage of pancreatic cancer, surgical intervention may not always be possible.

Chemotherapy

Chemotherapy drugs (intravenous or oral) can be used to help shrink tumors, alleviate symptoms, and extend survival time. However, the response to chemotherapy in cats with pancreatic cancer varies. Side effects are typically GI in nature (inappetence, vomiting, diarrhea).

Stereotactic Radiation Therapy

Stereotactic radiation therapy (SRT), also known as stereotactic radiosurgery (SRS), is a highly specialized form of radiation that can be used either when surgery is not an option or it can complement surgical procedures by shrinking any remaining tumor that may still be present or that could not be removed. SRT/SRS involves delivering high doses of radiation to the tumor while minimizing the damage to the normal surrounding tissues.

Palliative care

Palliative measures, such as pain management, dietary modifications, and supportive care, aim to improve the cat’s comfort and overall well-being. This approach is particularly important when other treatments are not feasible.

Prognosis

Sadly, the prognosis for cats diagnosed with pancreatic cancer is generally quite poor. Due to the aggressive nature of the disease and the limited treatment response, the median survival time is often short, ranging from a few weeks to a few months. However, every case is unique, and some cats may respond more favorably to treatment, resulting in extended survival. Quality of life issues should be discussed.

Pancreatic cancer in cats is a challenging disease with a guarded prognosis. Recognizing the signs and symptoms, early diagnosis, and timely intervention are crucial for improving the cat’s quality of life. Pet owners and their veterinary team should focus on providing compassionate care, managing symptoms, and supporting the cat throughout their cancer journey. In the future, as research progresses, we can work towards improving outcomes and treatment options for cats with pancreatic cancer.

¹ vsso.org