Home > Pancreas Diseases and Treatments > Diseases of the Pancreas > Pancreatic Cancer > Endocrine Tumors
Endocrine tumors account for less than 5% of all pancreatic tumors and are sometimes referred to as neuroendocrine or islet cell tumors. Islet cell tumors affect approximately 2500 people in the United States annually.
Some of these tumors secrete excessive amounts of hormone and are referred to as functional neuroendocrine tumors.
More common functional islet cell tumors include insulinomas and glucagonomas , whereas VIPomas, and somatostatinomas are much more unusual.
Nonfunctional tumors are less common and do not secrete excess hormones.
At the Pancreas Center, James Lee, MD specializes in treating neuroendocrine tumors.
Insulinomas arise from the islet cells of the pancreas and produce excessive amounts of insulin, resulting in low blood sugar. Typically small and noninvasive, these tumors are benign 90% of the time.
Symptoms include dizziness, fatigue, weakness, uncontrolled shaking, hunger, and at times psychiatric disturbances.
A history of fainting related to low blood sugar and weight gain commonly affects patients.
Diagnosis for this disorder requires observation of insulin level as it relates to blood sugar level.
A low blood sugar level combined with a high insulin level confirms the diagnosis that an insulinoma exists.
After diagnosis, the next step is localization of the tumor, accomplished using imaging studies including CT, MRI, octreotide scanning (injection of radioisotope into the vein and subsequent scanning to record the radiation given off by the radioisotope), and ultrasound.
However, in some patients, these imaging techniques are unable to localize the tumor.
In these cases, attempts to locate the lesion are performed by experienced endocrine surgeons during an operation and are successful in the majority of patients.
Treatment for an insulinoma usually includes surgical removal of the tumor.
Because these tumors are often small and benign, this surgery is curative.
Larger tumors may require removal of part of the pancreas depending on location.
Nonfunctional Neuroendocrine Tumors
Nonfunctional neuroendocrine tumors represent about 40% of all tumors affecting the islet cells.
These tumors are termed nonfunctional or clinically silent because they do not produce excessive hormones. They are slow growing and may be very large by the time of diagnosis. About half of these tumors are malignant.
Patients often suffer from nonspecific abdominal complaints or symptoms related to the biliary system (bile, bile ducts or gall bladder).
The most common diagnostic tests employed for these tumors are CT scans, octreotide scans, and pancreatic polypeptide/chromogranin level tests.
CT scans are most often used to evaluate the tumor in order to demonstrate its location within the pancreas and screen for spread of the disease to the liver. Octreotide scans are performed preoperatively to identify visible tumors and again postoperatively to screen for recurrence of disease.
Octreotide scanning involves injection of radioisotope into a vein, and subsequent scanning to identify sites of concentration. Because blood levels of pancreatic polypeptide and chromogranin are elevated in approximately 90% of patients with nonfunctional neuroendocrine tumors, physicians monitor these levels to evaluate patients for recurrence of disease as well.
The standard treatment for these tumors is surgical removal.
Due to the large size of the lesions at the time of treatment, almost all patients require removal of part of the pancreas, depending on the location of the tumor.
Tumors located in the tail of the pancreas require partial removal of the pancreas.
In many cases, this can be done while preserving the spleen, and in some cases minimally invasive techniques may be employed.
Tumors located in the head of the pancreas may require the removal of the head of the pancreas along with the duodenum.