Primary liver tumors in dogs and cats are rare. There are 4 types: hepatocellular tumors, bile duct tumors, neuroendocrine tumors, and sarcomas. These cancers can be massive, nodular, or diffuse in form. In dogs, most liver tumors are malignant, while in cats, most are benign. The signs of liver tumors range from being asymptomatic to having inappetence, fever, lethargy, and weight loss; and less commonly, nausea, vomiting and diarrhea; increased drinking and urination; and jaundice. Occasionally there are neurological signs, such as seizures. With tumor rupture and intrabdominal bleeding there may be weakness, collapse, and difficulty breathing. The diagnosis is based on history, clinical signs, exam findings, diagnostic imaging, and FNA or liver biopsy. A biopsy is best for a definitive diagnosis. Surgery is the treatment of choice for most primary liver tumors followed by chemotherapy. Chemoembolization is a newer treatment.
Lung tumors are considered rare in cats and dogs. Certain breeds are more predisposed to develop pulmonary tumors than others. Not all pets with pulmonary tumors exhibit clinical signs and are often diagnosed incidentally from routine chest X-rays. Ultrasound-guided fine needle aspiration or biopsy will confirm the diagnosis. Pulmonary carcinomas have a high tendency to metastasize, so full staging is recommended. Surgery is by far the most common treatment, though radiation therapy may be considered if surgery is not possible.
Lymphatic tumors are rare in pets. Lymphangiomas are benign and lymphangiosarcomas are malignant and have a moderate-to-high metastatic potential. Patients with lymphatic tumors typically have severe edema because of lymphatic obstruction. These types of tumors occur more frequently in young dogs and cats. Treatment usually involves surgical excision and chemotherapy may be used as a follow-up treatment in the case of lymphangiosarcomas.
Lymphocytes are specialized cells that function as part of the body's immune system, and are key cells in the body's ability to fight and prevent infection. Lymphocytes are found in the blood and tissues throughout the body, and are in particular concentration in lymph nodes and other 'lymphoid tissue'.
Lymphoma is a cancer of the lymphocytes. Lymphocytes are cells that are involved in the immune system. Lymphoma is connected with feline leukemia, a viral infection. Feline lymphoma most commonly affects the intestines. Therefore, clinical signs of lymphoma are often similar to other intestinal diseases. Diagnosing lymphoma requires finding cancerous cells on microscopic examination. Lymphoma cannot be prevented, but the likelihood of a cat developing lymphoma can be decreased by preventing feline leukemia virus infection.
Lymphoma is a cancer of the lymph nodes and lymphatic system. This cancer may be localized to one particular region, or may spread throughout the entire body. Lymphoma is a relatively common cancer, accounting for 15-20% of new cancer diagnoses in dogs. The prognosis for lymphoma varies, depending on various characteristics that can only be determined by specialized testing.
The most common forms of cutaneous lymphoma are epitheliotropic lymphoma and dermal lymphoma. No specific risk factors or causes have been identified in the development of cutaneous lymphoma. Generally, cutaneous lymphoma can appear as various-sized irritated, ulcerated, or infected patches anywhere on the skin, including the gums, nose, or lip margins. These areas may become ulcerated and bleed, or become crusted. Secondary infections are possible. By far, the most common treatment for cutaneous lymphoma is chemotherapy. Unfortunately, the response to treatment, although initially encouraging, is typically short-lived, with gradual return of the tumors.
Ferrets can suffer from tumors in any part of their body, ranging from benign cancers of the skin to aggressive malignant tumors of internal organs. A large number of ferrets are affected by tumors of the lymphoid system. This handout will discuss lymphomas and lymphosacromas.
Mammary tumors in dogs are not very common in North America due to routine spay procedures. Hormones play a role in tumor development in dogs. Dogs spayed before their first heat have only a 0.5% chance of developing mammary tumors. Certain breeds appear to be predisposed to developing mammary tumors. Mammary tumors are typically not painful and are usually discovered during routine examination by your veterinarian. Staging is recommended in all cases due to the tendency for these tumors to metastasize. Surgery is typically the treatment of choice and chemotherapy may be recommended after surgery.
Mammary tumors in cats are not very common in North America due to routine spay procedures. Hormones play a role in tumor development in cats. Cats spayed prior to 6 months of age have a reduced risk of developing mammary tumors. Siamese Cats appear to be predisposed to developing mammary tumors. Mammary tumors are typically not painful and are usually discovered during a routine physical examination. Staging is recommended in all cases due to the tendency for these tumors to metastasize. Surgery is typically the treatment of choice and chemotherapy may be recommended after surgery.