Differences in Symptoms: Benign vs. Malignant Tumors in

Section 1: What is a Tumor?

A tumor is a mass of cells that grow out of control. Tumors can be classified into two types: benign and malignant.

Benign tumors are formed by a cluster of irregularly growing cells that are bound together with surrounding tissues, with clear boundaries and no invasion of nearby tissues.

Malignant tumors, on the other hand, are caused by the uncontrolled growth of cells due to mutated genes, which can invade surrounding tissues.

Section 2: Causes of Tumors in Dogs

The causes of tumors in dogs are numerous and can be broadly categorized into the following:

1. Genetic Factors

① Oncogenes: Certain innate abnormal genes in normal cells interfere with normal cell growth and division, leading to tumor formation. To make it easier for owners to understand, let's use an analogy: cancer is like a good kid who turns bad due to environmental influences (normal cells mutate into cancer cells).

② Tumor Suppressor Gene Abnormalities: Genes produced in the body are supposed to suppress tumor growth. If there is an abnormality, it can cause uncontrolled growth of body cells.

③ When the genes that control the growth of bad cells in the body (representing tumor suppressor genes) mutate and can no longer control small tumors within the body, they can become large tumors.

2. Environmental Carcinogens

Viruses: Some viruses produce proteins that can affect cell growth, such as papillomavirus.

Chemicals: Pesticides have been confirmed to increase the risk of cancer in humans and pets, such as "toxaphene," commonly used in cotton fields to control pests. Additionally, preservatives in food like nitrates in sausages have been found to have carcinogenic effects in experimental animals.

3. Radiation

Longterm exposure to sunlight, where ultraviolet rays are easily absorbed, can cause certain tumors. Dogs that are longterm exposed to Xrays are also prone to diseases such as leukemia and thyroid tumors.

4. Hormonal Influence

Spaying female dogs before the age of 2 can significantly reduce their risk of breast cancer. Unneutered male dogs are particularly prone to anal gland tumors.

Section 3: Clinical Symptoms of Tumors in Dogs

Early tumor cells are very small and difficult to diagnose. It is only when the tumor diameter exceeds 1 centimeter that it becomes easier to detect. However, if the detected tumor is malignant, the malignant cells can spread to other organs, causing different symptoms depending on the affected organ. Owners can judge whether a dog has a tumor based on the following phenomena:

1. Pain

When tumors spread to bones or other tissues, they often cause arched pain, especially in cases of malignant osteosarcoma and multiple myeloma, which often lead to bone resorption. Therefore, if a dog has a persistent limping problem, owners should not ignore it and should pay special attention to such issues.

2. Fever

It usually causes periodic fever in dogs.

3. Poor Wound Healing

If there is poor wound healing, it is important to consider the possibility of cancer.

4. Other Symptoms

Many malignant tumors that spread to different organs do so through the bloodstream and lymphatic system. Different organs can cause different diseases. For example, dogs may experience vomiting, coughing, decreased appetite, diarrhea, difficulty breathing, glaucoma, sudden blindness, or epilepsy, among other symptoms. If a dog shows any of these symptoms, it is important to take them to the hospital for a timely checkup and treatment.

Section 4: Methods for Diagnosing Tumors in Dogs

1. Generally, when taking a dog to the hospital, the doctor will first perform a detailed pathological examination (such as auscultation, palpation, and percussion) and ask the owner some questions related to the dog's condition or perform blood tests to determine the disease.

Instrumental equipment for diagnosing cancer in dogs includes imaging examinations: Xray and photographic examinations.

2. Ultrasound: This is quite useful, but since ultrasound cannot penetrate bones and air, it is limited in examining bones and the lungs.

3. Computed Tomography (CT) and Magnetic Resonance Imaging (MRI): These two types of examinations can detect small tumors in the early stages. Additionally, MRI is a powerful tool in neuroimaging diagnosis. However, there are some issues with it.

Due to the high cost of the equipment, animal medicine in China has not yet adopted MRI and only uses CT. CT scanning requires anesthesia, and the cost of anesthesia is approximately 3,000 yuan.

4. Endoscopy and Bronchoscopy: These can diagnose the actual condition of the digestive and respiratory tracts.

5. Bone Marrow Biopsy: This can help understand the tumor in the bone marrow.

Section 5: Treatment Methods for Tumors in Dogs

Based on the characteristics of different tumors, different treatment methods are used, including surgery, chemotherapy, and radiation therapy. In fact, the treatment method for tumors can vary, and the recovery of dogs can also differ. For example, breast tumors can be effectively treated if they are discovered early, surgically removed, and treated promptly. However, the treatment for some tumors may not be very effective.

Tip: For more information about tumors in dogs, you can read "What to Do If Your Dog Has a Tumor."