Educational Articles

Cats + Tumors

  • A mast cell tumor (MCT) is a type of tumor consisting of mast cells. Mast cell tumors can form nodules or masses in the skin (and other organs), and cause enlargement of the spleen and intestine. Most mast cell tumors are seen as firm plaques or nodules in the skin. If your cat has the splenic form of the disease, the most commonly observed signs are weight loss, vomiting, and loss of appetite. The intestinal form, depending on how severe the disease is, may cause vomiting, diarrhea, fresh red blood in the stool, or black/tar-colored stool. This cancer is typically diagnosed via fine needle aspiration or biopsy. Surgical removal of the mass is the treatment of choice. Radiation therapy may also be suggested.

  • Mast cells originate or are formed in the bone marrow but complete their maturation in peripheral tissues. They are found in all tissues of the body but concentrate near surfaces in contact with the external environment such as the skin, respiratory and digestive tracts.

  • Melanocytes are cells that produce a pigment called melanin. A melanoma is an abnormal production of these cells in a dysregulated manner that forms a nodule, mass, or other form of lesion. Melanomas of the skin may develop anywhere on the body and are not typically bothersome. Toe melanomas, however, can be much more painful and concerning for your pet's health. Melanomas are often black in color but some do not produce pigment (amelanotic melanoma). Fine needle aspiration or biopsy may be used for diagnosis. Melanomas of the skin and toes are treated surgically and radiation therapy may be discussed.

  • Squamous cell carcinoma in situ is a disordered growth of the skin epidermis that may extend to include epithelium of the upper part of the hair follicles.

  • In some cases, chronic inflammation of the nose (rhinitis) leads to proliferation (hyperplasia) and formation of polyps in the nose or throat. These polyps are not cancerous but may need removal.

  • Neuroendocrine cells produce specialized chemical substances called neuroendocrine hormones. These hormones affect the rates of specific chemical reactions in nearby cells or in other tissues throughout the body.

  • Neuroendocrine cells produce specialized chemical substances called neuroendocrine hormones. These hormones affect the rates of specific chemical reactions in nearby cells or in other tissues throughout the body.

  • Oral papillomas (warts) are benign tumors of the epithelial lining of the mouth and throat caused by papillomaviruses. The esophagus may also be affected in severe cases.

  • Squamous cell carcinomas are malignant cancers originating from the lining cells of the mouth. They are locally invasive and often recurrent.

  • Osteosarcoma is the most common malignant bone tumor diagnosed in veterinary practice. It is considered similar to pediatric osteosarcoma in humans, a bone cancer that usually develops during the period of rapid growth that occurs in adolescence, as a teenager matures into an adult. Osteosarcoma is considered a rare cancer in cats.