| Persistent hypoglycaemia in infancy is most commonly caused by hyperinsulinism. A case is reported of the somatic loss of the maternal 11p in an insulin secreting focal adenoma in association with a germline SUR-1 mutation on the paternal allele in a baby boy with hyperinsulinism diagnosed at 49 days old. A reduction to homozygosity of an SUR-1 mutation is proposed as a critical part of the cause of focal hyperinsulinism. ( info) |
2/533. Unexpected MR-T1 enhancement of endocrine liver metastases with mangafodipir. With the use of available liver magnetic resonance contrast agents, such as mangafodipir (Mn-DPDP), liver metastases do not exhibit enhancement on T1-weighted images. This absence of enhancement is due to the lack of hepatocytes within these tumors. The purpose of this report is to demonstrate an unexpected enhancement on T1-weighted images 30 minutes after injection of mangafodipir, in the case of endocrine liver metastases from a non-hyperfunctioning neuroendocrine pancreatic tumor. Different hypotheses could explain this unexpected enhancement, such as increased arterial tumoral flow or high metabolic activity. Contrary to liver metastases of other origins, Mn-DPDP enhancement can be present in neuroendocrine metastases. J. Magn. Reson. Imaging 1999;10:193-195. ( info) |
| Pure pancreatic polypeptide-containing tumors (PPomas) are quite rare. Only 20 cases have been described. In this article we report a 75-year-old woman with such an endocrine islet cell tumor. The patient had no specific symptoms that could be ascribed to the tumor. An abdominal CT scan revealed a 3 cm soft tissue mass arising inferiorly from the tail of the pancreas. Local resection by way of a distal pancreatectomy was performed. A well-circumscribed hemorrhagic multiloculated mass, 3.7 cm in greatest dimension, was present in the tail of the pancreas. The patient has remained well and tumor free for the past 22 months. The endocrine characterization of the tumor was achieved by means of immunohistochemical analysis. Staining specific for insulin, glucagon, somatostatin, and gastrin was negative. In contrast, staining of the tumor for pancreatic polypeptide was strongly positive. A number of nonfunctioning islet cell tumors of the pancreas have been described. The lack of function has previously been suggested to indicate the lack of secretion of an endocrine product. This report documents that islet cell tumors may function by secreting pancreatic polypeptide but not cause symptoms. ( info) |
4/533. Islet cell tumor of the pancreas associated with tumor thrombus in the portal vein. We report the MR findings of a 70-year-old man with an islet cell tumor that diffusely involved the body of the pancreas associated with enhancing portal vein tumor thrombus and cavernous transformation. The diffusely infiltrative tumor mass was best shown on early post gadolinium spoiled gradient echo. The tumor thrombus enhanced intensely on early post gadolinium images and was also well shown on true FISP (Fast Imaging with Steady State Precession) images. The extent of liver metastases was best shown on fat suppressed T2-weighted images. The most unusual finding was tumor thrombus involving the SMV and portal vein. ( info) |
5/533. Ultrasound-guided laparoscopic resection of pancreatic islet cell tumors. Pancreatic islet cell tumors represent a diverse group of neuroendocrine lesions. These tumors may be singular or multiple, benign or malignant, sporadic, or part of the constellation of multiple endocrine neoplasia type 1. Tumors such as insulinomas and gastrinomas produce gastrointestinal peptides that lead to diagnosis. Nonfunctioning lesions may be found incidentally or by screening patients at high risk for such tumors. Successful management of patients with pancreatic islet cell tumors relies on accurate localization and sound operative technique. With proper preoperative localization, advanced laparoscopic methods can be used to manage patients with these pancreatic neoplasms. Preoperative localization of pancreatic islet cell tumors was difficult in the past. Standard imaging and localizing modalities, such as computed tomography scanning, magnetic resonance imaging, angiography, transabdominal sonography, and portal venous sampling, yield only 24% to 75% accuracy. Consequently, many biochemically suspected lesions cannot be imaged with current techniques. Decreased tactile sensation of laparoscopy adds complexity to intraoperative identification. Endoscopic sonography and laparoscopic sonography provide accurate preoperative and intraoperative localization to enhance laparoscopic and open resection. The authors treated two patients with islet cell neoplasms using endoscopic sonography to preoperatively visualize the tumors and laparoscopic sonography to guide laparoscopic enucleation. Their approach and difficulties are discussed. ( info) |
6/533. Nonfunctioning endocrine tumor of the pancreas with extrapancreatic growth and cyst formation: report of a case. We report a case of nonfunctioning endocrine tumor of the pancreas with extrapancreatic growth and cyst formation. A 48-year-old woman was admitted to our hospital with an upper abdominal mass, which was detected during a routine medical checkup. The preoperative diagnosis was a solid cystic tumor of the pancreas. The tumor, which measured about 7cm in diameter, arose from the head of the pancreas and had a thin stalk, measuring about 1 cm in diameter. The histopathological diagnosis was a malignant nonfunctioning endocrine tumor of the pancreas. Cyst formation occurred in 67% of the reported cases with extrapancreatic growth in japan. It is speculated that the cyst formation in this disease is related to the large size of the tumor and to the extrapancreatic growth. ( info) |
7/533. Hypercalcitoninemia in a sporadic asymptomatic neuroendocrine tumor of the pancreatic tail. BACKGROUND/AIM: Asymptomatic neuroendocrine tumors of the gastroenteropancreatic tract represent a significant challenge in terms of postoperative monitoring. methods: A case report of a calcitonin-secreting asymptomatic neuroendocrine tumor of the pancreatic tail is presented. RESULTS: Hypercalcitoninemia was noted in the 76-year-old Caucasian man who had a recurrent neuroendocrine tumor of the pancreatic tail. Upon pentagastrin stimulation, basal calcitonin increased only moderately from 82.3 (<10) to 100.9 and 125 pg/ml after 2 and 5 min, respectively. Surgical removal of the neuroendocrine tumor resulted in postoperative normalization of both basal and stimulated serum calcitonin levels. On immunohistochemistry, the neuroendocrine tumor was positive for calcitonin. CONCLUSION: Routine measurements of serum calcitonin might be a highly sensitive adjunct capable of identifying a subset of neuroendocrine tumors in which calcitonin monitoring may aid in the early detection of postoperative recurrence. ( info) |
8/533. Large and asymptomatic pancreatic islet cell tumor in a patient with multiple endocrine neoplasia type 1. The major phenotypes of multiple endocrine neoplasia type 1 (men 1) consist of three lesions characterized by hyperparathyroidism, pituitary tumors, and endocrine pancreatic tumors. The endocrine pancreatic tumors are a significant cause of disease-related mortality in men 1. Although symptomatic pancreatic tumors such as insulinoma and gastrinoma should be resected, the management of asymptomatic pancreatic tumors is not established. In asymptomatic pancreatic tumors, the most important factor is the propensity for malignant transformation of the tumors. Although there are no means to foresee it, the size of the pancreatic tumors might be predictive of malignant development in men 1. We report here a patient with men 1 who had a large asymptomatic pancreatic tumor. The patient (72-yr-old man) was diagnosed with primary hyperparathyroidism and underwent a total parathyroidectomy. Genetic examination showed a germline mutation of the MEN1 gene (E45G). Abdominal magnetic resonance imaging revealed a large (>6 cm) tumor with a heterogeneous pattern in the tail of the pancreas. No metastases of the tumor were evident. serum levels of insulin, gastrin, and glucagon were normal, and the patient had no symptoms. Operative resection was performed, and microscopic examination revealed that the tumor was an islet cell tumor stained with multiple hormones. This is a case indicating that asymptomatic pancreatic tumors associated with men 1 might be indolent independent of their size. ( info) |
9/533. Mixed duct-acinar-islet cell tumor of the pancreas: report of a case. A 72-year-old Japanese woman presented at our hospital complaining of altered consciousness on arising every morning. The laboratory findings showed hypoglycemia and hyperinsulinemia. Abdominal ultrasonography revealed a tumor in the body of the pancreas. With a diagnosis of insulinoma, a surgical excision of the tumor was performed. A light microscopic examination and an immunohistochemical study revealed the tumor to consist of duct, acinar, and islet cell components. Mixed tumors of the pancreas are rare, and their clinical features and pathogenesis remain unclear. A further accumulation of clinical cases as well as a large number of histopathological studies on these rare mixed tumors is needed. ( info) |
10/533. Insulin and somatostatin releasing islet cell tumor caused hypoglycemia. We report a hypoglycemic case with normal insulin levels, which was caused by an islet cell tumor that was releasing insulin and somatostatin. A fasting test suggested the over secretion of insulin. Moreover, this hypoglycemia was enhanced by the inhibitory effect of somatostatin on the secretion of insulin counter-regulatory hormones, such as glucagon, in addition to the autonomous secretion of insulin from the tumor. In cases of hypoglycemia with apparently normal insulin levels, the measurement of somatostatin and various provocative tests are recommended. Arterial stimulation venous sampling (ASVS) was useful to detect the location of this functioning islet cell tumor. ( info) |