What is cancer in dogs? Cancer in dogs, also known as canine cancer, refers to the abnormal growth of cells in a dog’s body. Just like in humans, cancer in dogs can occur in various parts of the body and can take many different forms. It is one of the leading causes of death in dogs, and can be a serious and potentially life-threatening condition.

What is Cancer in Dogs?
Cancer occurs when normal cells in a dog’s body start to grow and divide uncontrollably, forming a mass of abnormal cells called a tumor. Tumors can be benign, meaning they do not spread to other parts of the body and are not cancerous, or they can be malignant, meaning they have the potential to invade surrounding tissues and spread to other parts of the body, which is known as metastasis, and are considered cancerous.
Common types of cancer in dogs include:
- Skin cancer: Dogs can develop various types of skin cancer, including malignant melanoma, squamous cell carcinoma, and mast cell tumors.
- Lymphoma: Lymphoma, also known as lymphosarcoma, is a cancer that affects the lymphocytes, which are a type of white blood cells that play a role in the immune system.
- Hemangiosarcoma: Hemangiosarcoma is a highly aggressive cancer that arises from the blood vessels and can affect organs such as the spleen, liver, and heart.
- Osteosarcoma: Osteosarcoma is a type of bone cancer that is highly malignant and often affects the long bones of the limbs in dogs.
- Mammary gland tumors: Female dogs can develop mammary gland tumors, which can be benign or malignant.
- Mast cell tumors: Mast cell tumors are a type of skin tumor that can be benign or malignant and can occur in various parts of the body.
- Soft tissue sarcomas: Soft tissue sarcomas are tumors that can arise from various types of tissues in the body, such as muscle, fat, and connective tissue.
Signs and symptoms of cancer in dogs can vary depending on the type, location, and stage of the cancer. Common signs may include the presence of lumps or bumps, changes in behavior or appetite, weight loss, lethargy, changes in bathroom habits, and other general signs of illness.

Consult a Veterinarian For a Diagnosis
If you suspect that your dog may have cancer, it’s important to consult with a veterinarian for proper diagnosis and appropriate treatment options, which may include surgery, chemotherapy, radiation therapy, or other palliative care measures. Early detection and intervention can greatly impact the prognosis and outcome for dogs with cancer.