Adenocarcinoma in Cats

Adenocarcinoma is a type of cancer. Like all forms of cancer, the cells in the body grow uncontrollably in a specific location, invading vital surrounding structures. This mass growth of cells is called a tumor which, in the case of adenocarcinoma, is always malignant (cancerous) and invades other tissues. Tumors arising from glandular tissues that are benign (non-cancerous) are termed adenoma and do not invade surrounding tissues. Whether a tumor is malignant or benign, scientists are still puzzled as to what causes the cells to lose control of their growth. The body’s various types of cells are actively destroyed and replaced with new cells once they have carried out their ultimate function. However, something in the body changes this routine process and creates more cells than the body needs in one location.

Adenocarcinoma in cats is an aggressive form of cancer that arises from epithelium and glandular tissues throughout the body. Adenocarcinomas can affect many organs in a feline’s body, but the most common structures to be affected by these growths are the intestines, lungs, pancreas and kidneys. The way adenocarcinoma affects your cat depends on what tissues it is occupying, but most adenocarcinomas cause gastrointestinal distress such as vomiting and diarrhea. Adenocarcinoma, no matter which type your cat has, is a serious disease that is often fatal to felines.

Symptoms of adenocarcinoma in cats depend on where in the body the tumor has developed. The most common adenocarcinoma-associated symptoms in cats include: 

• Localized pain or discomfort 
• Palpable growth
• Reluctance to remain active
• Breathing difficulties
• Blood in the stool
• Mucus in the stool
• Diarrhea
• Vomiting 
• Prolonged infections
• Prolonged healing time 
• Lethargy 
• Depression
• Anorexia
• Distended abdomen
• Constipation  

Types

Since adenocarcinomas arise from glandular or epithelial tissues, and these tissues occur throughout the body, adenocarcinomas affect a number of internal structures. Common types of adenocarcinomas cancers in cats include: 

• Intestinal adenocarcinoma
• Mammary adenocarcinoma
• Kidney adenocarcinoma
• Lung adenocarcinoma
• Prostate adenocarcinoma
• Pancreatic adenocarcinoma
• Esophageal adenocarcinoma

The cause of adenocarcinoma in cats still remains unknown, as in many other forms of cancer. However, adenocarcinoma typically affects felines with tri-colored fur coats, Siamese cat breeds, and cats older than seven years of age. Experts believe that cancer itself occurs when cells grow uncontrollably in one location, but the question as to why this uncontrollable cell growth happens is still unanswered.

The diagnosis of adenocarcinoma in cats varies as the test the veterinarian selects will depend greatly on where the tumor is located. However, your cat doctor will always begin with a review of the feline’s medical history and discuss current symptoms with the pet owner. A physical examination might reveal evidence of a lump, indicating a mass underneath the skin or in one of the body’s organs. Blood work, especially a biochemistry profile, will likely be requested as this test will detect changes in organ secretions. If an organ is producing more or less of a hormone than normal, it could indicate that a massive growth is compromising its functionality.

Once the veterinarian has an idea of where the adenocarcinoma might be located, he or she may request an MRI or CT scan. These specialized scans will allow the vet to see abnormal tissues in the body as well as how far the growth has progressed. The doctor may then request a biopsy of the mass to determine cancer potential and decide on a treatment plan.

If at all possible, adenocarcinomas in cats are surgically removed, even if they are benign (non-cancerous), due to the large impact the growth has on the organ it is inhibiting. However, if the tumor has spread and removal of the mass has a high risk of life-threatening potential, your veterinarian may seek other forms of treatment. Chemotherapy and radiation therapy are commonly prescribed to adenocarcinoma patients, but age, as well as your cat’s overall health, should be taken into consideration. Old cats, infants, and cats with very poor immune function may not be good candidates for these treatments.

If your cat’s adenocarcinoma tumor was surgically removed, followed by cancer treating therapy, your cat has a positive prognosis. The majority of cats who have survived an adenocarcinoma live well over a year and only a select few have reported recurrences. There is no known way to prevent a cat contracting adenocarcinoma or to keep the disease from recurring in your feline. However, studies show that cats who maintain a proper diet, receive plenty of exercise, and live in a clean environment are less likely to develop an adenocarcinoma.