PET HEALTH CARE ARTICLES

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. This handout discusses uterine tumors in dogs and cats. The various types of these tumors, along with the clinical signs, diagnosis, treatment, and prevention of this condition are outlined.

Regular preventive health care for your cat can increase the length and quality of her life. Healthcare guidelines are established and kept up to date using the most recent evidence-based recommendations including the recommendation that all cats receive a complete veterinary examination at least once a year or more frequently, depending on their individual needs and health concerns.

Visceral vascular tumors are tumors which arise from blood vessels. The main tumor types are hemangiosarcomas (cancerous) and hemangiomas (benign). The clinical signs vary depending on the location of the tumor. Surgery is the recommended treatment option. Given the highly metastatic nature of hemangiosarcoma, chemotherapy is also recommended.

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.

Cancer is the result of genetic damage to cells. While some breeds may be more predisposed to certain forms of cancer, age-related changes and environmental factors are also often at fault. Some tests can be performed to determine the type of cancer present. Treatment options are available but do not necessarily cure cancer.

Tumors of the urinary tract may present anywhere from the kidneys to the tip of the urethra. Tumors of the bladder are most common in the dog whereas tumors involving the kidneys are more prevalent in cats. Unfortunately, many tumors of the urinary tract are malignant and treatment options may be limited. Surgery is possible in select cases. Medical treatment may be beneficial in cases where surgery is not possible.

Thyroid tumors can be benign or malignant and functional or non-functional. In dogs, they are usually malignant and non-functional, whereas in cats, they are usually benign and functional. A swelling in the neck may be the only sign in a dog; however, a change in bark, coughing, difficulty swallowing, facial swelling, rapid breathing, breathlessness, weight loss, and a loss of appetite are possible. In cats, the signs are related to excess thyroid hormone production (hyperthyroidism). Thyroid tumors are diagnosed with a physical examination, bloodwork, various forms of diagnostic imaging, and in dogs, a tissue biopsy. In dogs, staging is required to determine the presence of spread. A variety of treatment options are available.

Skin gland, hair follicle, and sebaceous gland tumors are often benign. Matrical carcinoma 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 surgical removal and histopathology. Further treatment is reviewed.

Testicular tumors are generally not aggressive and have a low metastatic rate. Pets with undescended testicles (cryptorchid) are predisposed to the development of certain testicular tumors. 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.

Stomach tumors are uncommon in dogs and cats. There are many kinds, including leiomyosarcomas, lymphomas, adenocarcinomas, mast cell tumors, fibrosarcomas, plasmacytomas, gastrointestinal stromal tumors (GISTs), and carcinoids (all malignant); and leiomyomas, adenomatous polyps, and adenomas (benign). Most tumors are malignant. Stomach tumors are more prevalent in older animals, males, and certain breeds. The signs of stomach tumors include chronic vomiting, inappetence, lethargy, and weight loss. Sometimes tumor ulceration will cause anemia. Paraneoplastic syndromes are possible with the muscle tumors. Stomach tumors may be diagnosed with imaging, endoscopy, or surgery, with a biopsy. Treatment may involve surgery, chemotherapy, or radiation therapy.