Endocrine glands produce chemical agents, known as hormones. These play a crucial role in the regulation of various bodily functions.
Hormones carry important cellular information. E.g. insulin enables glucose to migrate from bloodstream into cells whereas thyroid glands influence the person`s activity level. A complicated regulatory mechanism ensures that hormone levels in a healthy individual´s bloodstream match requirements of day-to-day living. If hormone producing cells are damaged, too little or too much of the substance will be generated and the regulatory mechanism will start to malfunction.
Environmental influences and genetic alterations can lead to malignant changes in hormone producing cells and to uncontrolled growth, however without malignant virulence.
Endocrine tumors of the pancreas
a. The Insulinom
The insulinom is the main pancreatic hormone-producing tumor. Insulin production without an inhibiting regulatory mechanism is a direct consequence of this tumor. Not enough glucose can remain in the bloodstream which leads to such well-known symptoms as outbreak of sweat, shaking, heart pounding, weakness, impaired vision, anxiety, agressivity, and at worst unconsciousness. Patients often become overweight when they discover that these symptoms disappear with the intake of food. When fasting, signs of an unusual lack of blood sugar are found. Locating these tumors can be very difficult as they are usually small and several tumors can exist. An effective therapy will seek to remove the tumor(s) from the pancreas. If metastases are present and cannot be removed directly, chemotherapy is necessary.
b. The Gastrinom
The gastrinom is another common form of a hormone-producing tumor. It will often be found in the pancreas (80% of cases), however other organs can also be affected (stomach, duodenum). Often malignant, this tumor can produce metastases at an early stage. Patients suffer from stomach and intestinal ulcers generated by the gastrin hormone. Usually these can not be influenced by medication. Gastrin triggers the production of stomach acid. The surgeon will attempt to remove the tumor, and if metastases are found, an attempt to alleviate symptoms with acid-inhibiting medication will be made. In earlier times, the patient´s stomach was removed to prevent further formation of ulcers, as stomach acid production will cease with the removal of the organ.
c. VIPom and Glukagonom
VIPom and glucagonom are rare tumors. Usually they are found in or near the pancreas. Glucagonom and diabetes mellitus share a set of similar symptoms, such as elevated blood sugar levels. Patients also suffer from alterations of skin appearance. The Vermer-Morrison-syndrome is present If an endocrine tumor leads to the production of VIP (vasoactive intestinale polypeptid). This hormone triggers secretion in the small intestine and in the pancreas and leads to watery diarrhoea, potassium-salt and chloride deficiencies in the secretion of the stomach-intestinal system. The patient suffers from excessive acidic saturation. In any such case it is difficult to identify and locate the tumor. Even small tumors generate metastases at a very early stage, a fact which necessitates chemotherapy as well as habitually administered treatments.
d. Other Endocrine Tumors
Some endocrine tumors will not produce any measurable hormone quantities, which often makes detection difficult. Growth characteristics and metastases production set these tumors apart from the common carcinome found in the pancreatic duct. Different surgical procedures and different radiation therapy / chemotherapy approaches are needed.