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  • Writer's pictureVetMed Team

Stomach Cancer in Cats: 8 Symptoms To Look Out For

Stomach cancer, although relatively rare in cats, poses a serious health concern for felines. The complexities surrounding its onset, progression, and plethora of symptoms make early detection and treatment pivotal for prolonging and enhancing the quality of a cat's life. This article delves deep into understanding stomach cancer in cats, its causes, symptoms, and available treatments.

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What is Stomach Cancer in Cats?

Stomach cancer refers to malignant tumors that originate in the cat's stomach lining. These tumors can vary in size and nature. There are several types of stomach tumors that can develop, with adenocarcinomas being the most common. Adenocarcinomas start in the glandular tissue and tend to be particularly aggressive, often invading surrounding tissues and spreading to other parts of the body.

In addition to adenocarcinomas, lymphomas, which are cancers of the lymphatic system, can also affect the stomach. While lymphomas can be present anywhere in the body, when they manifest in the stomach, they can be challenging to differentiate from adenocarcinomas without appropriate diagnostic tests.

What Causes Stomach Cancer?

The exact causes of stomach cancer in cats remain uncertain. However, several potential contributing factors have been identified based on clinical observations and research:

  • Genetic Factors: Just as in humans, certain genetic mutations may predispose cats to developing stomach cancer. While the exact genes remain unidentified, hereditary components cannot be ignored.

  • Dietary Factors: Chronic ingestion of carcinogenic compounds present in some foods, particularly those that are preserved with chemicals or improperly stored, may contribute to the development of stomach cancer.

  • Chronic Gastritis: Long-term inflammation of the stomach lining, known as chronic gastritis, might increase the risk of cancerous changes in the stomach's mucosal layer.

  • Age: Stomach cancer is more commonly diagnosed in older cats, suggesting that age-related factors or the cumulative effect of exposure to carcinogens might play a role.

  • Environmental Factors: Exposure to certain environmental toxins and chemicals might escalate the risk, although definitive links are yet to be established in cats.

  • Helicobacter Infection: Some studies suggest a potential link between the presence of certain types of Helicobacter bacteria and the onset of stomach cancer, although this correlation is still under investigation.

It's crucial to understand that while these factors might increase the risk, their presence doesn't confirm that a cat will develop stomach cancer. Every cat is unique, and multiple factors often interact to contribute to the disease's onset.

Can You Prevent Stomach Cancer?

While the prospect of preventing any cancer is compelling, the multifaceted nature of stomach cancer, especially in cats, makes it challenging to guarantee prevention. However, there are strategies and measures cat owners can take to potentially reduce the risk of their feline companion developing this malignancy.

  • Balanced Diet: Feed your cat high-quality commercial cat food or a veterinarian-approved homemade diet. Avoid foods with artificial preservatives and ensure the food is stored correctly to prevent contamination.

  • Limit Exposure to Toxins: Minimize your cat's exposure to known and potential carcinogens. This includes certain household chemicals, pesticides, and secondhand smoke.

  • Regular Veterinary Check-ups: Schedule routine veterinary visits to detect any signs of chronic gastritis or other predisposing conditions. Early detection and management of such conditions can potentially reduce the risk of malignant transformation.

  • Maintain Optimal Weight: Obesity can exacerbate many health issues in cats, potentially including an increased risk for various cancers. Regular exercise and portion control are key to maintaining a healthy weight.

  • Prompt Treatment of Gastric Issues: If your cat shows symptoms of persistent stomach upset, seek veterinary care promptly. Chronic untreated gastric issues can lead to prolonged inflammation, a potential precursor to cancer.

  • Safe Environment: Ensure your cat's living environment is safe and free from potential hazards. If your cat is an outdoor explorer, be vigilant about the areas they have access to, avoiding places where they might come in contact with harmful chemicals or toxins.

  • Genetic Awareness: If possible, gain awareness of your cat's genetic background, especially if it's a purebred. Some breeds may have a predisposition to certain cancers, so knowledge can guide preventive care.

While these measures can contribute to a healthier, longer life for your cat and potentially reduce the risk of stomach cancer, they do not guarantee prevention. Regular veterinary check-ups remain crucial to monitor your cat's health and detect any anomalies early on.

What Are the Symptoms of Stomach Cancer in Cats?

Stomach cancer in cats can manifest in various ways, and its symptoms often overlap with other gastrointestinal conditions. Recognizing these symptoms is essential for early detection and intervention. Here are eight common symptoms associated with stomach cancer in felines:

1. Vomiting

One of the most noticeable signs is frequent vomiting. The cat might throw up its food shortly after eating, or there could be the presence of blood in the vomit, which may appear as fresh blood or have a coffee ground-like consistency.

2. Weight Loss

Unexplained and sudden weight loss is a concerning sign in many diseases, including stomach cancer. The cat might be eating less due to nausea or might not be absorbing nutrients efficiently.

3. Lack of Appetite

Cats with stomach cancer often show a diminished interest in food. They might approach their food bowl with eagerness, only to walk away without eating or eat far less than usual.

4. Abdominal Discomfort or Swelling

The presence of a tumor or inflammation in the stomach can cause discomfort or palpable swelling in the abdominal region. Cats might show reluctance when picked up or might adopt a hunched posture.

5. Lethargy

A decrease in energy levels or overall activity can be another indicator. The cat may prefer to rest more often, avoid play, or not engage in its usual routines.

6. Black, Tarry Stools

The presence of digested blood in the feces gives it a black, tarry appearance. This can indicate bleeding within the stomach or upper intestinal tract.

7. Difficulty Swallowing

Some cats with stomach cancer might show signs of dysphagia or difficulty swallowing. This can result from a tumor situated near the esophageal entrance or generalized inflammation.

8. Excessive Drooling

While cats naturally groom and might occasionally drool, excessive or continuous drooling can be a sign of oral discomfort or nausea, both of which can be associated with stomach cancer.

It's essential to remember that while these symptoms can indicate stomach cancer, they can also be signs of other gastrointestinal disorders or conditions. If any of these symptoms are observed, it's crucial to consult with a veterinarian for a thorough examination and appropriate diagnostic tests.

How Quickly Can Stomach Cancer Form and Progress?

Stomach cancer, like other forms of cancer in cats, is a complex disease whose development and progression can be influenced by a multitude of factors, including genetic predispositions, environmental triggers, and the individual health of the cat.

  • Initial Development: The initial formation of stomach cancer can be insidious. Cellular changes leading to cancerous growths might begin months or even years before any clinical symptoms become noticeable. Precancerous lesions or small tumors can remain asymptomatic for extended periods.

  • Growth Rate: Once formed, the growth rate of the tumor can vary widely. Some tumors are slow-growing and might take years to reach a size where they cause noticeable symptoms. Others can be aggressive, growing and spreading rapidly within months. The type of cancerous cells (whether they're adenocarcinomas, lymphomas, etc.) can influence the growth rate.

  • Metastasis: One of the most concerning aspects of stomach cancer, and indeed any cancer, is its ability to spread to other parts of the body. When cancer cells break away from the primary tumor and establish secondary tumors in distant organs, it's known as metastasis. Some forms of stomach cancer in cats are more prone to metastasize than others. If metastasis occurs, it often significantly complicates treatment and worsens the prognosis.

  • Influence of External Factors: Dietary factors, chronic inflammation or infections, exposure to carcinogens, and overall health can influence how quickly stomach cancer progresses. For instance, a cat with a weakened immune system might be less equipped to fight off cancerous changes, leading to faster progression.

  • Detection and Intervention: The speed at which stomach cancer is detected and treated can significantly impact its progression. Early detection, while the tumor is still small and localized, can lead to more successful treatment outcomes. Conversely, late detection, especially after metastasis, can make treatment more challenging and decrease survival rates.

How Stomach Cancer is Diagnosed in Cats

Diagnosing stomach cancer in cats requires a multi-faceted approach, given that the symptoms can often mimic those of other gastrointestinal disorders. Comprehensive examinations and specific tests are crucial in establishing an accurate diagnosis.

Physical Examination

The initial step in diagnosing any ailment typically starts with a thorough physical examination by the veterinarian. During this assessment, the vet may palpate the cat's abdomen to check for any irregularities, masses, or areas of discomfort. Observing the cat's overall health, weight, and demeanor also provides valuable clues.

Blood Tests

Blood tests are essential diagnostic tools. A complete blood count (CBC) and chemistry panel can reveal if the cat is anemic, which might be due to gastrointestinal bleeding, or if there are any abnormalities in organ function. These blood tests can give an overview of the cat's general health and can indicate potential problems that warrant further investigation.

Imaging Studies

Imaging modalities, like X-rays and ultrasound, provide a clearer picture of what's happening inside the cat's body. X-rays might show abnormalities in the stomach's shape or size, while an abdominal ultrasound can offer more detailed insights, such as the presence of tumors, their size, and their exact location. These imaging studies are indispensable for visualizing structural changes in the stomach and surrounding areas.


An endoscopic procedure involves inserting a flexible tube with a camera into the cat's stomach. This allows the veterinarian to view the stomach's interior directly, helping identify any unusual growths, ulcers, or other abnormalities. If suspicious areas are found, tissue samples can be taken during this procedure for biopsy.


If a mass is detected through imaging or endoscopy, a biopsy is often the next step. This involves taking a small sample of the suspicious tissue, which is then examined under a microscope by a pathologist. A biopsy can confirm whether the mass is cancerous, and if so, the type of cancer and its grade, which can guide treatment options.

Treatment Options For Stomach Cancer in Cats

Treating stomach cancer in cats depends on various factors including the type of tumor, its location, its size, and how much it has spread. It's essential to work with a veterinarian to develop a comprehensive treatment plan tailored to the individual cat's needs. Here are the primary treatment options available:

HDR Brachytherapy

HDR (High-Dose Rate) Brachytherapy is a form of radiation therapy where radioactive materials are placed directly into or near the tumor. This allows for a high dose of radiation to be delivered to the tumor while minimizing exposure to surrounding healthy tissues.

VetMed specializes in this method, providing a minimally invasive option that often has fewer side effects compared to external beam radiation. The precision of HDR Brachytherapy makes it particularly advantageous for treating specific tumors.


If the tumor is localized and hasn't significantly metastasized, surgical removal might be the recommended treatment. The affected portion of the stomach is removed, and then the remaining parts are sutured back together. The success of the surgery depends on the tumor's location and extent. Post-operative care is crucial, and the cat might require special dietary considerations and pain management.


This involves using drugs to kill or slow down the growth of cancer cells. Chemotherapy might be used after surgery to eliminate any remaining cancer cells or as a standalone treatment for inoperable tumors. Cats generally tolerate chemotherapy better than humans. However, side effects such as reduced appetite, lethargy, or gastrointestinal disturbances might still occur.

Radiation Therapy

High-energy beams are targeted at the tumor to destroy cancer cells. It's often used for tumors that are inoperable or as an adjunct therapy post-surgery. Some cats might experience mild side effects such as skin irritation or temporary hair loss at the treatment site.

Palliative Care

If the cancer is too advanced, or if the owner opts not to pursue aggressive treatments, palliative care focuses on providing the cat with the best quality of life. This might involve pain management, nutritional support, and other comfort measures. The goal is to ensure the cat remains comfortable and free from pain. Regular vet check-ups are recommended to monitor and manage symptoms.

Nutritional Support

Proper nutrition is vital for cats undergoing cancer treatment. A specialized diet might be recommended to ensure the cat gets all the necessary nutrients while accommodating any digestive issues. Cats with stomach cancer might have a reduced appetite or face difficulty in digesting certain foods. A vet or a veterinary nutritionist can guide the best dietary choices.

Recovery and Management For Stomach Cancer in Cats

The recovery and management process for feline stomach cancer patients is a critical aspect of their overall treatment journey. The time immediately after treatment, as well as the long-term care, play essential roles in determining the quality of life for the affected cat and the potential prognosis. Here's a detailed look into the recovery and management aspects:

Post-Treatment Monitoring

  • Immediate Aftercare: After surgery or any invasive procedure, cats will need to be monitored for pain, complications, or side effects from anesthesia. Vets might prescribe painkillers and advise on wound care for surgical sites.

  • Regular Check-ups: Regular vet visits are essential to monitor the progress of recovery, check for recurrence of tumors, and manage any side effects of treatments like chemotherapy or radiation.

Dietary Adjustments

  • Specialized Diets: Cats recovering from stomach cancer might require a specially formulated diet that's easy to digest and promotes healing. This might include soft foods or prescription diets.

  • Hydration: Ensuring the cat remains well-hydrated is crucial. Fresh water should always be available, and in cases where the cat isn't drinking enough, subcutaneous fluid administration might be needed.

Pain Management

  • Medications: Cats might experience pain or discomfort after treatments. Vets will typically prescribe pain medications and provide guidelines on dosage and monitoring for potential side effects.

  • Alternative Therapies: Some cat owners opt for complementary treatments like acupuncture or massage to help manage pain and improve their cat's overall well-being.

Emotional Well-being

  • Comfortable Environment: A stress-free environment can help cats recover faster. This might involve providing a quiet space, soft bedding, and toys.

  • Affection and Attention: Regular interaction and gentle petting can help soothe a recovering cat and reinforce the bond between the pet and the owner.

Medication Adherence

  • Consistency: If the cat is on medications, it's vital to administer them as prescribed. Missing doses or incorrect dosage can affect recovery.

  • Monitoring: Watch for any side effects or unusual behaviors after medication. Some drugs might cause digestive issues or drowsiness.

Long-Term Management

  • Regular Screenings: Even after successful treatment, there's a risk of cancer recurrence. Regular screenings and vet check-ups are essential to detect any issues early on.

  • Physical Activity: Gentle play and moderate exercise can help the cat maintain muscle tone and overall health. However, always consult with the vet about the appropriate activity level for the recovering feline.

The recovery and management of a cat with stomach cancer go beyond the initial treatments. It encompasses a comprehensive approach to ensure the feline patient not only survives but thrives, enjoying a good quality of life post-diagnosis. Proper monitoring, a supportive environment, and adherence to medical advice are the pillars of successful recovery and management.

VetMed Treats Stomach Cancer in Cats

At VetMed, we understand the emotional toll a diagnosis of stomach cancer in your beloved feline companion can bring. Our unwavering commitment is to provide cutting-edge, compassionate care to cats diagnosed with stomach cancer. We combine medical expertise with a heart-centered approach. We recognize that cats are not just pets; they are family. As we navigate the challenging journey of stomach cancer together, you can trust in VetMed's commitment to delivering the best care possible for your feline friend.


Questions You've Asked Us About Stomach Cancer in Cats

Still have questions? Contact us here - we promise we'll answer them.

How long do cats with stomach cancer live?

The lifespan of cats with stomach cancer varies based on diagnosis and treatment, with early detection often leading to a better prognosis. With appropriate treatment, 12-14 months is usually added to the cat’s lifespan.

What are signs of stomach cancer in cats?

How do you treat a tumor in a cat's stomach?

Is stomach cancer in cats painful?

How fast does stomach cancer spread?


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