Neuroendocrine Tissue Tumors in Dogs

Neuroendocrine tissues are tissues that have both nervous system and hormone-producing functions. They are found in a number of locations throughout the body. Tumors develop occasionally from neuroendocrine cells in the adrenal or thyroid glands, digestive tract, or pancreas. These tumors can be benign or malignant. Even if benign, a growing tumor can disrupt nearby normal tissues and, in some cases, secrete excess hormone.

Insulinomas Functional Islet Cell Tumors (Insulinomas) The pancreas is composed of several types of cells that have distinct functions involved in the production of hormones and digestive enzymes. The exocrine pancreas produces enzymes that are... read more , gastrinomas Gastrin-secreting Islet Cell Tumors (Gastrinomas) The pancreas is composed of several types of cells that have distinct functions involved in the production of hormones and digestive enzymes. The exocrine pancreas produces enzymes that are... read more , and glucagonomas Disorders of the Pancreas in Dogs The pancreas is composed of several types of cells that have distinct functions involved in the production of hormones and digestive enzymes. The exocrine pancreas produces enzymes that are... read more are all neuroendocrine tissue tumors that develop in the pancreas. Pheochromocytomas Pheochromocytomas The adrenal glands are located just in front of the kidneys. The adrenal gland has 2 parts—the cortex and the medulla. The adrenal cortex is subdivided into 3 layers, and each layer produces... read more develop in the medulla of the adrenal gland.

Tumors that develop from C-cells in the thyroid occur less often than other types of thyroid tumors, and they are less likely to spread to other parts of the body. Diarrhea is the most common sign of these types of tumors. Treatment options include surgery, radiation, chemotherapy, and radioactive iodine.

Chemoreceptor organs are derived from neuroendocrine tissue. They can detect very small changes in the carbon dioxide and oxygen content and pH of the blood, and they help regulate breathing and circulation. Tumors in chemoreceptor tissue usually develop principally in either the aortic body (found in the chest) or in the carotid bodies (found in the neck). Tumors of the aortic and carotid bodies are seen most often in brachycephalic breeds of dogs, such as Boxers and Boston Terriers. The tumors do not secrete excess hormone but may cause problems by placing pressure on the heart, blood vessels, and nerves. Aortic body tumors are more common but are less likely to spread to other parts of the body (metastasize) than carotid body tumors.