Educational Articles

Cats + Tumors

  • Squamous cell carcinoma (SCC) is a tumor of the cells that make up the contact or upper layer of the skin. UV light exposure has been described as a developmental factor in people and appears to be associated with the development in cats. Areas affected include the ear tips, skin, toes, or peri-ocular region. Fine needle aspiration or biopsy may be performed for diagnosis. The metastatic rate does not appear overly clear, though staging is always recommended. SCC of the toe can occur as a primary tumor or may have spread from the lung (lung-digit syndrome). Surgery is almost always recommended in any case of SCC; the role of chemotherapy is controversial. Radiation therapy has an excellent response rate in cats with the SCC affecting the nasal planum and may give long-term tumor control.

  • Tumors of the epithelial, glandular stomach lining include non-cancerous polyps and some types of chronic (hyperplastic) gastritis. Malignant epithelial tumors (gastric adenocarcinomas) cause progressive illness.

  • Skin gland, hair follicle, and sebaceous gland tumors are more commonly found to be benign. Matrical carcionoma and sebaceous gland adenocarcinoma are rare and more aggressive forms of the disease. Regardless of the type (sweat, hair, or sebaceous) diagnosis is made by fine needle aspiration, biopsy, and/or initial surgical removal and histopathology. In the majority of cases, surgery is recommended and other treatments are unnecessary. Chemotherapy and/or radiation therapy in pets with matrical carcinomas or sebaceous gland adenocarcinomas may be recommended.

  • The three most common testicular tumors are seminomas, Sertoli cell tumors, and interstitial cell tumors. Though other tumor types are possible, testicular tumors as a whole are generally not aggressive and have a low metastatic rate. Pets that are cryptorchid are predisposed to the development of Sertoli cell tumors and seminomas. Hyperestogenism is possible with Sertoli cell tumors. In any cryptorchid pet, removal of both testicles should be pursued. Intraabdominal tumors in cryptorchid pets may cause lethargy, decreased appetite, and fever. Standard staging is recommended in all cases, including a rectal exam. Surgery is typically the treatment of choice and may be combined with radiation therapy or chemotherapy if metastasis is evident.

  • The thyroid gland is a two-lobed endocrine gland wrapped partially around the front of the trachea (windpipe) just below the throat. Its function is the production and release of thyroid hormones.

  • Primary Kidney tumors are rare in dogs and cats. When they do occur, they are almost invariably malignant (invasive and spreading) and are called renal carcinoma. These tumors tend to invade the adjacent tissues including the main blood vessel draining the kidney (renal vein).

  • Uterine tumors are quite rare in North American pets, mainly due to routine spaying practices. Several types of tumors can arise from the tissues of the uterus. How the tumor will affect your pet is entirely dependent on the location and type of tumor. By far, uterine cancer is most commonly diagnosed by abdominal ultrasound or during a spay procedure. Full staging is recommended prior to surgery to determine if the cancer has metastasized. Treatment for solitary masses without evidence of spread typically involves ovariohysterectomy. If metastasis is present, chemotherapy should be considered, however its efficacy is not completely known. Without evidence of spread, uterine tumors carry a good prognosis.

  • Vascular tumors of the skin develop from the blood vessels of the skin. These tumors may arise anywhere on the body and appear as a firm and raised lump on or under the skin. Hemangiomas may ulcerate and bleed; hemangiosarcomas may bleed into the surrounding tissues. This type of tumor is typically diagnosed via a tissue biopsy or surgical removal of the entire tumor. Surgery is the recommended treatment for vascular tumors of the skin.

  • Visceral vascular tumors are tumors that develop from the blood vessels found in the internal organs of the body, most commonly the heart, liver, and spleen, although other locations, such as the urinary bladder, are possible. There are two forms of visceral vascular tumors: hemangiomas and hemangiosarcomas. Certain breeds, such as German Shepherds, Labrador Retrievers, and Golden Retrievers, are particularly predisposed to developing hemangiosarcoma. The clinical signs vary depending on the location of the tumor. This type of tumor is often diagnosed with ultrasound of the chest or abdomen depending on the location of the tumor. Surgery is the recommended treatment option and chemotherapy may be recommended.

  • Cancer is classically described as the abnormal growth of a specific cell type with the potential to invade many parts of the body and damage organs or tissues. Cancer has many hallmarks, including its ability to evade the immune system’s safeguards, uncontrollably proliferate, and metastasize (spread). Several genetic and environmental factors have been implicated in the development of cancers, though their origin is likely multifactorial. This handout broadly describes what cancer is, what causes it, what the signs are, and how it can be diagnosed and treated.