A minute nonfunctioning islet cell tumor demonstrating malignant features

We report a patient with a minute nonfunctioning islet cell tumor, 8mm in diameter, which demonstrated malignant features by histology. The patient was a 43-year-old Japanese woman, who had an elevated carbohydrate antigen (CA) 19-9 level, of 59U/ml (normal range, <37U/ml) identified on a health check to rule out malignancies. Ultrasonography and computed tomography demonstrated a well-defined pancreatic tumor, 8mm in diameter, in the body of the pancreas. Serum levels of pancreatic hormones were within normal limits, and thus a tentative diagnosis was nonfunctioning islet cell tumor. The size of the tumor remained unchanged for 1¹/₂ years, but, at this time, the serum level of CA19-9 was elevated to 253U/ml. Segmental pancreatectomy was performed because malignancy could not be ruled out. The resected specimen showed an endocrine tumor invading both the pancreatic parenchyma and the perineural spaces outside the tumor. In general, minute nonfunctioning islet cell tumors have been considered to be completely benign, but the present tumor showed clear malignant features. We might have to take surgical resection into consideration even if the size of such an endocrine tumor is minute.     

Portal Vein Resection for a Portal Vein Thrombus Caused by Nonfunctioning Islet Cell Carcinoma: Report of a Case

We report a case of nonfunctioning islet cell carcinoma of the pancreas causing a tumor thrombus in the portal vein. The patient was a 60-year-old woman whose presenting symptoms were abdominal pain, vomiting, and weight loss. We performed a subtotal pancreatectomy and splenectomy combined with partial resection of the portal vein. Histopathological studies confirmed the diagnosis of nonfunctioning islet cell carcinoma of the pancreas with a tumor thrombus in the portal vein. The patients postoperative course was uneventful and she is doing well 25 months after the operation.     

Huge endocrine tumor of the pancreas

We report a case of a huge endocrine tumor of the pancreas. A 76-year-old woman was admitted for a left upper abdominal mass. She showed neither hormonal symptoms nor abnormal serum hormone levels. Ultrasound imaging showed that a heterogeneously solid and partly calcified tumor was located in the retroperitoneal space. Computed tomography showed a hypervascular tumor with central degeneration. Open laparotomy revealed that the tumor originated from the pancreas; it was removed in a mass including the spleen and the pancreatic body and tail. The resected specimen demonstrated that the 580-g tumor was multi-lobulated, encapsulated, and 14 × 14 × 7cm in size. Microscopically, the tumor consisted of cuboidal cells with round nuclei; the cells formed palisade and trabecular structures. Immunohistologically, chromogranin A, neuronspecific enolase, and glucagon were positive only for the tumor cells. Final diagnosis was endocrine tumor of the pancreas immunohistochemically producing glucagon. No tumor recurrence has been found 3 years after the surgery. We conclude that huge tumors in the retroperitoneal space must be differentiated from nonfunctioning endocrine tumors of the pancreas because the clinical course is markedly different.     

Pancreatic polypeptide islet cell tumor: Case report and review of the literature

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, ghicagon, somatostatin, and gastrin was negative. In contrash 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 fimction 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.     

Laparoscopic resection for nonfunctioning small glucagon-producing tumor: report of a case and review of the literature

Glucagonoma is a relatively rare type of pancreatic endocrine tumor, and is often well-developed and malignant at detection. We report a case of nonfunctioning small glucagon-producing tumor that was successfully resected by laparoscopic surgery. A 63-year-old woman was admitted to our hospital for further examination of a pancreatic tumor that had been detected incidentally. Hematological data and hormone concentrations were within normal ranges. Abdominal ultrasonography and computed tomography showed a small mass in the body of the pancreas. Laparoscopic distal pancreatectomy was done. Macroscopically, the resected tumor was a yellowish-white, solid mass measuring 8 x 8 x 7 mm. The tumor cells showed positive immunohistochemical staining for chromogranin A and glucagon. The postoperative course was uneventful. To the best of our knowledge, this is the first report of laparoscopic surgery for a nonfunctioning small glucagon-producing tumor. Because of recent improvements in laparoscopic surgery technique, use of this approach for resection of pancreatic benign small endocrine tumors will likely increase in the future.     

无功能胰岛细胞瘤诊断与治疗(附20例报告)

目的　探讨无功能胰岛细胞瘤的临床特征和诊治方法。方法　收集我院1990～2004 年收治的无功能性胰岛细胞瘤20例,对其临床表现、检查手段和治疗结果进行分析回顾行分析。结 果　B型超声、SCT、MRI检查能提供肿瘤的位置,定性诊断主要靠术中冰冻病理切片检查。20例均 行手术治疗,其中16例随诊4个月～15年,良性12例,恶性4例,其中2例随诊复发而诊断为恶性。 结论　无功能胰岛细胞瘤发病隐匿,术前诊断困难,SCT,MRI对定位定性诊断有一定价值;术中病 理诊断有助于确定选择术式,病人随访对确定良恶性有帮助。     

"Nonfunctioning" islet cell carcinoma of the pancreas

Although most pancreatic islet cell tumors are associated with clinically evident hormone hypersecretion, a small group have no obvious signs or symptoms of excess endocrine activity and are termed "nonfunctioning." The clinical course of eight patients with "nonfunctioning" islet cell carcinoma seen during an eight-year period was reviewed. The six men and two women ranged in age from 36 to 68 years (mean--52). The initial complaint in six was a palpable abdominal mass associated with pain, steatorrhea, or jaundice. Two patients presented with abdominal pain that was initially thought to be of biliary tract origin, and the tumor was discovered at operation. Two patients underwent radical distal pancreatectomy and have no gross evidence of residual or recurrent tumor one and two years later. Five had a biopsy and biliary diversion; three of these also had a gastrojejunostomy. Five were given postoperative 5-fluorouracil and streptozotocin chemotherapy. One developed renal dysfunction and was switched to dimethyltriazenoimidazole carboxamide (DTIC) chemotherapy. Three patients are alive four, six, and eight years, respectively, after diagnosis. Two expired two and a half and three years after diagnosis. One patient had only biopsy of peripancreatic nodes, and he expired in one year. "Nonfunctioning" islet cell carcinoma presents with symptoms related to the mass effects of the tumor. An aggressive therapeutic approach utilizing surgery and chemotherapy is advocated for these slow growing neoplasms.     

Nonfunctioning islet cell carcinoma of the pancreas with an initial appearance of massive hemorrhage

Diagnosis of nonfunctioning tumors is difficult, since they often lack apparent clinical signs and symptoms. Here we report nonfunctioning islet cell carcinoma of the pancreas with massive hemorrhage. A 57-year-old woman who had sudden severe abdominal pain and high fever was admitted to our hospital. A series of examinations after admission revealed cystic tumor located at the tail of the pancreas and a hematoma adjacent to the tumor. The plasma levels of hormones, except for prolactin, were normal. After antibiotic treatment, blood transfusion, and other conservative therapy had produced a stable condition, operation was performed. The operation revealed a tumor measuring 6.2×7.8×7.2 cm located at the pancreatic tail and a hematoma 3.2×2.7×2.5 cm adjacent to the tumor. Distal pancreatectomy, including the tumor, combined with splenectomy and removal of the hematoma, was carried out. The surgical specimen showed a nonfunctioning islet cell carcinoma arising from the pancreatic tail; this tumor had ruptured and was bleeding. Seventeen months after the operation, the patient is alive without recurrence or symptoms. The major characteristic in this patient was the sudden severe abdominal pain and shock due to bleeding from the tumor, which features may not have been reported in the literature.     

The use of somatostatin receptor scintigraphy in the differential diagnosis of pancreatic duct cancers and islet cell tumors.

OBJECTIVE: In the present study, the diagnostic value of somatostatin receptor scintigraphy (SRS) was evaluated in the preoperative workup in patients with pancreatic duct cancers and islet cell tumors, as well as in the follow-up of these patients. METHODS: Twenty-six patients with suspected primary pancreatic duct cancers and 48 patients with islet cell tumors were studied. The SRS was performed using the radionuclide-labeled somatostatin analogue 111In-octreotide. Another group of 12 patients who were still alive more than 3 years after pancreaticoduodenectomy for pancreatic duct adenocarcinomas also underwent SRS. RESULTS: In 31 (65%) of 48 patients, the primary pancreatic islet cell tumor as well as its often previously not yet recognized metastases could be visualized. In contrast, none of the 26 pancreatic adenocarcinomas or their metastases could be seen. In 5 of 12 patients who were alive more than 3 years after pancreaticoduodenectomy for pancreatic duct adenocarcinomas, metastatic lesions were visualized at SRS. In retrospect, these patients were not operated on for adenocarcinomas but for "nonfunctioning" islet cell tumors. CONCLUSIONS: The present study supports the concept that SRS has a place in the preoperative differential diagnosis of islet cell tumors and pancreatic duct cancers as well as in the follow-up, especially in those cases in which no tumor histologic analysis was obtained, or the pathologic examination of the tumor tissue had not included special staining procedures for neuroendocrine characteristics. Our results also indicate that the evaluation of the results of investigations on the role of surgery or radiation therapy and chemotherapy or both in pancreatic duct cancer have to be interpreted with caution, if no histologic analysis and staining for neuroendocrine characteristics was performed.     

Laparoscopic enucleation of a nonfunctioning neuroendocrine tumor at the head of the pancreas.

OBJECTIVE: Laparoscopy is a safe, feasible technique for benign pancreatic pathologies and has been increasingly reported for neuroendocrine tumors located at the body and tail of the pancreas. We report a case of successful enucleation of a nonfunctioning neuroendocrine tumor located at the head of the pancreas, in a patient with multiple endocrine neoplasia type I. METHODS: A 5-cm nonfunctioning neuroendocrine tumor at the pancreatic head was identified by computerized tomography scan. Laparoscopic ultrasound did not reveal additional tumors on any other part of the pancreas. RESULTS: Enucleation was successfully performed for this solitary tumor because of its favorable position. Histology revealed an islet cell tumor. No postoperative complications occurred and recovery was rapid. CONCLUSION: Laparoscopic enucleation of neuroendocrine tumor at the pancreatic head is safe and feasible for select patients.     

胰腺内分泌肿瘤的诊断与外科治疗

目的提高胰腺内分泌肿瘤的诊断和治疗水平。方法回顾性分析1978年1月至2004年12月经手术治疗、病理证实的38例胰腺内分泌肿瘤病人的临床资料。结果胰腺内分泌肿瘤以胰岛素瘤和无功能性胰岛细胞瘤最常见,分别占57．9%和36.8%,恶性胰岛素瘤和多发性胰岛素瘤各占胰岛素瘤的13．6%,无功能性胰岛细胞瘤中恶性占64．3%;21例(95%)胰岛素瘤成功术前定位和手术切除,1例多发性胰岛素瘤摘除术后 4年后复发,再次手术治愈;86％无功能性胰岛细胞瘤患者以无痛性肿块入院,肿瘤平均大小为8．5cm,6例行胰体尾部切除,4例行胰十二指肠切除,2例行肿瘤摘除,1例行囊肿内引流术,1例行活检术;全组术后并发胰瘘7例(18%)。结论 B超、CT是胰腺内分泌肿瘤有效的诊断方法,肿瘤局部剜出与规范切除是治疗胰腺内分泌肿瘤的有效方法,其预后较好。     

A case of nonfunctioning islet cell tumor with hyperammonemia and hyperamylasemia

A case of nonfunctioning islet cell tumor with hyperammonemia and hyperamylasemia is reported. A 67-year-old female was admitted in an unconsciousness state, with a large abdominal mass about 10×10 cm in size. Hyperammonemia and hyperamylasemia were evident. Blood sugar levels, electroencephalogram (EEG), and brain scan were normal. After admission, lactulose and gabexate mesilate were administered for the hyperammonemia and hyperamylasemia. Serum ammonia levels returned to the normal range within 2 weeks, but serum amylase levels failed to decrease. Results of the oral glucose tolerance test were normal. A contrast computed tomographic (CT) scan revealed a tumor with a homogeneous enhancement pattern. Angiography demonstrated a hypervascular pancreatic tumor. Distal pancreatectomy with splenectomy was performed on the basis of a preoperative diagnosis of pancreatic tumor with extrapancreatic growth. Histological examination showed nonfunctioning islet cell tumor, with evidence of vascular invasion of tumor cells. Production of pancreatic hormones was not noted. The patient promptly returned to normal consciousness, and no elevation of ammonia or amylase was observed other than an incidental elevation of the latter due to pseudocyst formation. The hyperamylasemia was obviously related to tumor growth, and the pancreatic tumor itself may have contributed to the hyperammonemia.     

An extramural gastrointestinal stromal tumor of the duodenum mimicking a pancreatic head tumor

We report the case of a 53-year-old woman with a gastrointestinal stromal tumor (GIST) of the duodenum that showed only extramural growth, mimicking a pancreatic tumor. Preoperatively, computed tomography (CT) and angiography revealed a hypervascular mass, 3.0 cm in diameter, in the pancreatic head. Hypotonic duodenography showed compression of the second and third portions of the duodenum by the pancreatic lesion. Endoscopic examination showed no specific mucosal abnormalities in the duodenal lumen. The pancreatic head tumor was diagnosed preoperatively as a nonfunctioning islet cell tumor of the pancreas, and the patient underwent pylorus-preserving pancreaticoduodenectomy. A hard mass was palpated intraoperatively in the pancreatic head region, and neither peritoneal dissemination nor metastasis was detected. Histologically, the tumor was composed of spindle-shaped cells with a fascicular growth pattern, and only a few mitotic features were seen. Immunohistochemically, most of the tumor cells were positive for c-kit oncoprotein and CD34, but negative for alpha-smooth muscle actin and S-100 protein. Therefore, this neoplasm was finally diagnosed as a duodenal GIST of the uncommitted type. This is a rare case of a duodenal GIST with exclusively extramural growth mimicking a pancreatic head tumor.     

Nonfunctioning islet cell carcinoma of the pancreas associated with massive intra-abdominal hemorrhage

Pancreatic islet cell tumors are rarely associated with intra-abdominal hemorrhage. We report herein a rare case of nonfunctioning islet cell carcinoma associated with massive hemorrhage into the abdominal cavity caused by spontaneous rupture of the tumor. A 44-year-old man presenting with sudden upper abdominal pain was admitted to his local hospital on April 18, 1994. On April 19, a laparotomy was performed with the diagnosis of peritonitis. Massive hemorrhage of unknown origin occurred, and he was transferred to our hospital in a state of hypovolemic shock. Imaging findings revealed massive hematoma in the abdominal cavity and a hypervascular tumor arising from the body of the pancreas. Because the hemorrhage was life-threatening, an emergent re-laparotomy was performed on April 20. Apart from the massive hemorhhage, a pancreatic tumor (60 × 35 × 30 mm in size) with spontaneous rupture was noted. Distal pancreatectomy, combined with splenectomy and removal of the hematoma, was performed. Histological findings revealed an islet cell carcinoma of the pancreas with venous invasion. Peritoneal dissemination, liver metastasis, and lymph node metastasis were not observed. The patient is alive without recurrence 6 years and 5 months after the operation. Received: October 12, 2000 / Accepted: April 24, 2001     

非功能性胰岛细胞瘤16例临床分析

目的探讨非功能性胰岛细胞瘤的诊断和治疗方法。方法对近16年间收治的非功能性胰岛细胞瘤16例临床资料回顾性分析。其中位于胰头部4例,胰体尾部12例,瘤体长径平均12cm。结果行肿瘤摘除术6例,胰十二指肠切除术3例,行包括肿瘤在内的远端胰腺及脾脏切除3例,保留脾脏的胰体尾切除术3例,因肿瘤广泛侵浸未能切除1例。治愈性切除率为93.75%(15/16),全组无手术死亡。随访资料显示:11例良性肿瘤患者全部存活,已2～16年。5例恶性肿瘤患者中,1例因肿瘤广泛侵犯未能切除者,术后5个月死于多器官衰竭;1例胰体尾切除并左肝切除者存活2年;胰十二肠切除者2例,分别存活1年和6年,胰体尾切除加脾切除1例已存活12年8个月。结论钡餐,B超,CT,MRI,以及ERCP对该病有诊断价值,手术切除是治疗非功能性胰岛细胞瘤的主要方法,效果良好。     

Non-functioning tumors of the endocrine pancreas. Concept, diagnosis, treatment

Five cases of nonfunctioning islet cell tumors of the pancreas are reported. There were 3 males and 2 females aged from 34 to 83 years (Average: 55.8 years). Two tumors were malignant since already metastatic, one tumor was probably malignant and two tumors were judged as benign. One patient died post-operatively. The four remaining patients are alive without recurrence after from 1.4 to 7.3 years. The concepts of nonfunctioning tumors of the pancreas and APUD system are discussed in view of these 5 cases and the relevant literature. The value of tumor markers as well as the radiographic appearances of these tumors are reported. Having a better prognosis than the adenocarcinoma of the exocrine pancreas, the nonfunctioning tumors of the endocrine pancreas are best managed by surgery. The indications and the results of surgery and chemotherapy are discussed.     

Management of Nonfunctioning Islet Cell Carcinomas

Tumors arising from the pancreatic islet cells are rare and represent a heterogeneous group of benign or malignant lesions. Most tumors present with well characterized syndromes, whereas others appear to be nonfunctioning. The clinical features of 11 men and 7 women with nonfunctioning islet cell carcinomas operated on between 1983 and 1998 were reviewed. The median patient age was 53.5 years (range 26–74 years). The most frequent presenting symptoms were abdominal pain (13 patients), weight loss (7 patients), and obstructive jaundice (4 patients). Gut hormone profiles were normal in all patients. Abdominal sonography and computed tomography localized the tumor in 17 patients, and correct prediction of an endocrine tumor was achieved in 12 patients. Six of seven patients showed a hypervascular tumor upon angiograpy, and seven of eight patients preoperatively had positive somatostatin receptor scintigraphy. At operation, regional or distant metastases were present in 15 (83%) and 6 (33%) patients, respectively. Eleven patients underwent potentially curative resections, and the remaining seven patients were managed palliatively by resection (four patients) or bypass procedures (three patients). Three patients had up to three more resection for metastases. Eight patients received postoperative octreotide, interferon α therapy, or both. The overall cumulative 5- and 10-year survival rates were 65.4% and 49.1%, respectively. Of the 11 patients who underwent curative resection, 10 were alive after a median follow-up of 63 months (range 7–180 months), but only 5 are free from disease. Although surgical cure is rare in nonfunctioning islet cell carcinomas, significant long-term palliation can be achieved in a large proportion of patients with an aggressive surgical approach and, when indicated, additional medical therapy.     

Malignant islet cell tumor projecting into the main pancreatic duct

We report herein a rare case of islet cell tumor showing a unique growth pattern in a patient who developed repeated acute pancreatitis as the tumor's initial symptom. Preoperative imaging examinations showed dilatation of the main pancreatic duct (MPD) and cysts around the pancreatic tail. A distal pancreatectomy with splenectomy was performed because the pancreatitis was localized in the distal pancreas and was not controlled by various drug therapies. Grossly, the tumor consisted of two component parts: a markedly infiltrative part in the pancreatic parenchyma, and a papillary elevated part in the MPD. The MPD was obstructed by the tumor spreading widely along the distal MPD. Microscopically, the tumor was composed entirely of islet cell tumors (nonfunctioning), with several foci of venous and lymphatic involvement. Based on its growth behavior, we assumed that the tumor may have arisen from the MPD or from islet cells closely adjacent to the MPD. The patient's postoperative course was uneventful and he is doing well 2 years after the operation. We discuss the growth pattern of the tumor and the cause of the pancreatitis. Received: March 30, 2000 / Accepted: July 12, 2000     

A nonfunctioning islet cell carcinoma with tumor thrombus in both the portal and splenic veins — a case report of successful resection

A rare case of nonfunctioning islet cell carcinoma associated with tumor thrombi in both the portal and splenic veins is reported. The patient, a 49-year-old male, had a 2-year history of occasional abdominal pain. Computed tomography (CT) disclosed a huge mass in the body of the pancreas, and celiac arteriogram showed a tumor stain in the body and tail of the pancreas. Percutaneous transhepatic portography (PTP) demonstrated an irregular filling defect, indicating intraportal tumor growth. Curative surgery, which included total pancreatectomy with combined resection (50 mm in length) and reconstruction of the portal vein, distal gastrectomy, and partial resection of the transverse colon, was performed. Histological examination of the surgical specimen led to a diagnosis of nonfunctioning islet cell carcinoma with a negative immunohistochemical stain for insulin, glucagon, somatostatin, and adrenocorticotropic hormone. The patient has been well for 38 months to date without any sign of tumor recurrence. Our experience with this case has introduced a radical resection for islet cell tumor of the pancreas, even if the tumor has extended into the portal vein.     

Nonfunctioning islet cell carcinoma of the pancreas: case report

Islet cell carcinomas have an incidence of 5 per million per year; 50 per cent of these are nonfunctioning islet cell tumors. The presenting symptoms mimic pancreatic ductal adenocarcinoma. The CT finding of a pancreatic head mass that spares the main duct may distinguish between the two. The treatment of choice is resection. Most nonfunctioning islet cell tumors are not discovered until metastases are present. However, favorable survival rates have been reported in locally advanced tumors that have undergone resection. Liver metastases carry an unfavorable prognosis. Five-year survival over 60 per cent has been reported. Node-negative patients have a median survival of more than 10 years, and node-positive patients who have undergone resection have a median survival of 75 months. Streptozotocin and 5-fluorouracil are used postoperatively in patients with advanced disease. Considering the favorable survival with resection aggressive surgical treatment is mandated in cases of nonfunctioning islet cell tumors.