Ampullary somatostatinoma: psammomatous variant of gastrointestinal carcinoid tumor--an immunohistochemical and ultrastructural study. Report of a case and review of the literature

Duodenal Epithelial Neoplasms Complicating von Recklinghausen's Disease: An Immunohistochemical Analysis in Two Patients

The authors report two patients with von Recklinghausen's disease and carcinoid tumors of the duodenum; one patient, in addition, also showed complications of an adenocarcinoma of the ampulla of Vater and multiple schwannomas, while the other patient was associated with an leiomyoblastoma of the duodenum. Histologically, both carcinoid tumors demonstrated glandular structures and psammoma bodies. Immunohistochemically, both carcinoid tumors stained diffusely positive against somatostatin. Duodenal carcinoid tumors associated with von Recklinghausen disease are characterized by originating in an ampullary lesion, by the presence of glandular structures, psammoma bodies, or both, and by being rich in somatostatin. A high prevalence of duodenal carcinoids has previously been recognized in patients with von Recklinghausen's disease, however, the association of adenocarcinoma of the small intestine and von Recklinghausen's disease is extremely rare.

Carcinoids and high-grade neuroendocrine carcinomas of the ampulla of vater: a comparative analysis of 139 cases from the surveillance, epidemiology, and end results program-a population based study

CONTEXT

Neuroendocrine tumors of the ampulla of Vater constitute a heterogeneous group of neoplasms clinically and morphologically. Because they are rare, little is known about their demographics and biologic behavior.

OBJECTIVE

To analyze the demographics and the 5- and 10-year relative survival rates of 139 patients with carcinoid tumors and high-grade neuroendocrine carcinomas of the ampulla.

DESIGN

Using data from National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program from 1973 to 2006, we analyzed the demographics, morphology, and survival of patients with carcinoids and neuroendocrine carcinomas of the ampulla.

RESULTS

SEER recorded 6081 cases of malignant neoplasms of the ampulla, of which 82 were carcinoid tumors and 57 were high-grade neuroendocrine carcinomas. Of these 57, 42 were neuroendocrine carcinomas, not otherwise specified; 9 were small cell carcinomas; and 6 were large cell neuroendocrine carcinomas. The incidence was higher in men than in women. Patients with carcinoid tumors were younger (mean age, 61.6 years) than those with high-grade neuroendocrine carcinomas (mean age, 67.5 years). Carcinoid tumors were smaller than high-grade neuroendocrine carcinomas. The frequency of lymph node metastasis was 28.5% for carcinoid tumors and 62% for high-grade neuroendocrine carcinomas. The 5- and 10-year relative survival rates of patients with carcinoid tumors were 82% and 71%, respectively. The 5- and 10-year relative survival rate of patients with high-grade neuroendocrine carcinomas was 15.7%.

CONCLUSIONS

Carcinoids of the ampulla of Vater are relatively rare. Carcinoids and high-grade neuroendocrine carcinomas of the ampulla are biologically and clinically similar to these tumors arising in other sites. Carcinoids were smaller and metastasized less frequently than high-grade neuroendocrine carcinomas.

Primary extra-ampullary duodenal neuroendocrine carcinoma in an adult male

A primary extra-ampullary duodenal neuroendocrine carcinoma was found in a 40-year-old man who presented with upper abdominal pain and weight loss. Duodenoscopy and hypotonic duodenography revealed a protruding fungating mass with luminal occlusion at the third part of the duodenum (D3). Although the metastatic work-up was normal, the tumor was inoperable intraoperatively, hence a palliative bypass was carried out followed by chemotherapy with 5-fluorouracil and leucovorin. Examination of the biopsy by immunohistochemistry and ultrastructural study revealed it to be neuroendocrine in nature, expressing synaptophysin, chromogranin and cytokeratin and containing dense core cytoplasmic granules. However, there was no evidence of clinical endocrinopathy. The present case emphasizes the need for better detection, further analysis and evaluation of such rare cases to identify their clinical course and effective treatment modalities.

[Type I neurofibromatosis, pheochromocytoma and somatostatinoma of the ampulla. Literature review]

Gastrointestinal involvement in Von Recklinghausen's neurofibromatosis (autosomal dominant disease) is observed in 25% of patients and is frequently represented by duodenal carcinoids. We report a case of somatostatinoma of the ampulla in a 42-year-old female with neurofibromatosis and pheochromocytoma and show a literature review about the association of neurofibromatosis and somatostatinoma. This pathological association appears non hasardous and surgical ampullectomy offers a good alternative to pancreaticoduodenectomy in localised tumors treatment.

Primary small-cell neuroendocrine carcinoma of the duodenum - a case report and review of literature

BACKGROUND

Small-cell neuroendocrine carcinoma in the duodenum is an extremely rare neoplasm with poor prognosis.

CASE PRESENTATION

A 57-year-old man presented with sudden onset gastrointestinal bleeding and fainting attacks. Duodenoscopy and hypotonic duodenography revealed a 3 x 3 cm protruding tumor with ulcerations situated opposite the ampulla of Vater in the second part of the duodenum. Local excision of the tumor was performed, followed by adjuvant chemotherapy with 5-fluoro uracil and leucovorin. Examination of the tumor by immunohistochemistry and electron microscopy indicated it to be neuroendocrine in nature, expressing synaptophysin and AE1/AE3, and containing dense core granules. The patient showed no sign of recurrence and has been disease-free for more than 48 months after surgery.

CONCLUSIONS

Most cases of small-cell neuroendocrine carcinoma in the duodenum show rapid progression of the disease, and even radical surgery with or without chemotherapy do not prevent death. We report a rare subtype of small-cell neuroendocrine carcinoma. This subtype appears to have a much better prognosis, and may be amenable to local excision, if the lesion is away from the ampulla of Vater.

[Duodenal somatostatinoma. Anatomic/clinical study of 12 operated cases]

STUDY AIM

Duodenal somatostatinomas (DS) are very rare neuro-endocrine tumours. The aim of this retrospective and multicentric study was to report the clinical and pathological characteristics of these neoplasms in a series of 12 patients and to compare them with the literature.

PATIENTS AND METHODS

From 1987 to 1998, 12 patients were operated for a DS. There were seven women and five men ranging in age from 23 to 72 years (mean age: 56.6 years). Four patients had an associated von Recklinghausen's disease, one of them with multiple endocrine neoplasia (MEN type IIa) and medullary carcinoma of the thyroíd. The surgical procedures were pancreaticoduodenectomy (n = 8), small bowel resection (n = 2), inferior gastrectomy (n = 1) and gastrojejunostomy with hepatic metastases biopsies (n = 1). The tumour was mainly located on the 2nd duodenum (n = 10), with a mean size of 2.7 cm (ranging from 0.4 to 6 cm) and with a pancreatic invasion in three patients. A metastatic disease was present at the time of diagnosis in eight patients. There were, according to Capella's classification, two patients in the groups I and II, and ten patients in group III (83%), respectively.

RESULTS

There was one postoperative death after a pancreaticoduodenectomy. Three patients secondarily died from tumoral progression. Eight patients were alive, with a mean follow-up of 84 months (ranging from 5 to 290 months), at the end-point of the study.

CONCLUSION

Duodenal somatostatinomas are rare neuroendocrine, generally non-functioning, well-differentiated tumours with a low grade of malignancy. The association with the von Recklinghausen's disease is frequent. The clinical somatostatinoma syndrome with diabetes, diarrhea and biliary lithiasis is rare. The treatment is surgical even with a metastatic disease. The 5-year survival rate is better than those of the pancreatic somatostatinomas or the duodenal gastrinomas.

Somatostatinoma of the ampulla of vater in celiac sprue

The increased incidence of gastrointestinal lymphoma and adenocarcinoma in patients with celiac sprue is well recognized, with 10% to 15% developing a gastrointestinal malignancy. Somatostatinomas are rare neuroendocrine tumors that occur most commonly within the pancreatic head or duodenum. Although fewer than 100 cases have been reported, somatostatinomas are often associated with multiple endocrine neoplasia-1 syndrome and von Recklinghausen's disease. The unusual case of a 43-year-old woman with celiac sprue in which a somatostatinoma involving the ampulla of Vater was identified and resected is presented. To our knowledge, somatostatinomas have not been previously reported in patients with celiac sprue.

Carcinoid somatostatinoma of the duodenum

Carcinoid somatostatinoma is a rare neuroendocrine malignant tumour and the duodenal location is an atypical site of presentation of which only few cases have been reported in the literature. A case of duodenal carcinoid somatostatinoma metastatic to lymph nodes in a 66-year-old patient is presented with an update of the literature. No relevant signs or symptoms were associated to the retrogastric lymph-node mass, which deformed but did not infiltrate the stomach wall. At the first and third portion of the duodenum, two polipoid endoluminal nodules (size 1 cm) were found with adjacent adenopathy partially adherent to the head of the pancreas and with thickening of the antropyloric wall. The patient underwent antrectomy duodenum mobilization and lymphadenectomy in the hepatic artery region. The treatment was successful and, over 3 years after diagnosis, there has been no clinical or radiological evidence of relapse. Duodenal somatostatinoma is rare and its diagnosis is often incidental. Surgery would be the appropriate treatment in the early stage of the disease with good chances of cure.

Von Recklinghausen's disease associated with duodenal somatostatinoma: contrast of duodenal versus pancreatic somatostatinomas

A case of Von Recklinghausen's disease with duodenal somatostatinoma is reported. A search of the world's literature revealed 27 patients with Von Recklinghausen's disease associated with an immunohistologically proved duodenal somatostatinoma. Twenty-nine cases of duodenal somatostatinoma not associated with Von Recklinghausen's disease and 32 cases of pancreatic somatostatinomas have been identified for comparison. While their histology may be similar in many respects, the duodenal and pancreatic somatostatinomas show significant differences, especially in hormonal and growth behaviors. In contrast to its pancreatic counterpart, the duodenal somatostatinoma is frequently associated with Von Recklinghausen's disease, is seldom associated with a recognizable "somatostatin syndrome," often contains psammoma bodies, and is less frequently associated with demonstrable metastases at the time of operation.

Carcinoid of the ampulla of Vater. Clinical characteristics and morphologic features

BACKGROUND

Carcinoid tumors of the gastrointestinal tract are most common localized in the appendix, followed by the small intestine, the rectum, and the stomach. The localization of these tumors at the ampulla of Vater is extremely seldom.

METHODS

In the present study the authors describe two patients with carcinoid tumors of the ampulla Vater and review 71 previously published cases.

RESULTS

Most patients presented with jaundice, but without carcinoid syndrome. Because the tumor grows submucosally, preoperative diagnosis was correct only in 15%. Most tumors were around 2 cm in size. Metastasis to lymph nodes and/or liver was present in 45%. Standard treatment is Whipple resection or local excision in small tumors.

CONCLUSIONS

Carcinoid tumors of the ampulla of Vater are an extremely rare clinical entity. Generally, the prognosis is good with a 5-year survival period of 90%.

Neuroendocrine carcinoma of the stomach with extensive somatostatin immunoreactivity

Upper gastrointestinal tract neuroendocrine tumors producing predominantly somatostatin have thus far been described only in the duodenum; their characteristic features include the frequent presence of psammoma bodies (psammomatous somatostinomas), and the association with von Recklinghausen's neurofibromatosis. Gastric neuroendocrine tumors, on the other hand, tend to display immunoreactivity to serotonin but may include small subpopulations producing gastrin, motilin, pancreatic polypeptide, and somatostatin. In this report we describe a neuroendocrine carcinoma of the stomach with rapidly fatal outcome, displaying neurosecretory granules by electron microscopy and immunoreactivity to pan-neuroendocrine markers, ie, chromogranin and neuron-specific enolase. The only neuroendocrine regulatory peptide detected in the tumor was somatostatin, identified by immunohistochemistry in the majority of neoplastic cells. In contrast with duodenal somatostinomas, there were no psammoma bodies and no demonstrable association with von Recklinghausen's neurofibromatosis. To our knowledge this appears to be the first report of a malignant neuroendocrine tumor with diffuse somatostatin immunoreactivity.

Carcinoids and endocrine cell micronests of the minor and major duodenal papillae. Their incidence and characteristics

BACKGROUND

There have been no reports about the incidence and characteristics of carcinoids and endocrine cell micronests (ECM) of the minor and major duodenal papillae.

METHODS AND RESULTS

The minor and major duodenal papillae of 78 consecutive autopsy and 117 surgical specimens were examined histologically using mirror-image paraffin-embedded tissue samples. ECM were found frequently in these areas in hematoxylin and eosin-stained sections, and their aggregation patterns were classified into four types: nodular type (Type 1, 2 of 167 in the minor papilla and 1 of 145 in the major papilla), scattered type (Type 2, 39 of 167 and 6 of 145), orifice type (Type 3, 7 of 167 and 0 of 145), and islet-like type (Type 4, 14 of 145 and 0 of 145, respectively). Criteria of neoplastic or nonneoplastic ECM were defined tentatively by histologic and immunohistochemical analyses of the ECM. Type 4 was regarded to be atrophic or regenerating islets of Langerhans. Distinct carcinoids (Type 1), neoplastic ECM (39% of all Type 2 and 3), and nonneoplastic ECM (61% of all Type 2 and 3) were found in 1.2%, 9.0%, and 16.2% of 167 samples of the minor papilla and 0.7%, 1.4%, and 2.8% of 145 specimens of the major papilla, respectively. The endocrine cells composing the carcinoids and the ECM usually were immunoreactive for somatostatin and/or pancreatic polypeptide (PP). They were negative for S-100 beta.

CONCLUSION

In duodenal papillae, especially in the minor duodenal papilla, carcinoids and ECM seem to occur more frequently than generally thought, and predominantly consist of somatostatin and/or PP containing cells.

von Recklinghausen's disease associated with somatostatin-rich duodenal carcinoid (somatostatinoma), medullary thyroid carcinoma and diffuse adrenal medullary hyperplasia

This report describes the concomitant occurrence of a somatostatin-rich duodenal carcinoid, a medullary thyroid carcinoma and a diffuse adrenal medullary hyperplasia in a patient with von Recklinghausen's disease. A 50-year-old Japanese man died from lung metastasis of a malignant schwannoma. In addition to extensive viscero-cutaneous neurofibromatosis, two different types of neuroendocrine tumors were found in the duodenum and thyroid gland at autopsy. The duodenal tumor, which was located in the second portion, showed the histologic appearance of a carcinoid tumor with glandular differentiation and psammoma-bodies. Immunohistochemically the tumor cells were intensely positive for somatostatin. The thyroid tumor was composed of nests of tumor cells arranged in an endocrine pattern, and showed immunoreactivity for calcitonin. A review of the literature revealed no previously reported case of concomitant occurrence of duodenal somatostatinoma and medullary thyroid carcinoma in a single patient with von Recklinghausen's disease. Morphometric analysis of adrenal glands disclosed the presence of diffuse medullary hyperplasia. Thus, the present case exhibited a similarity in some respects with multiple endocrine neoplasia (MEN) syndrome, Type IIa or IIb.

Histopathology, hormone products, and clinicopathological profile of endocrine tumors of the upper small intestine: A study of 44 cases

Forty-two duodenal and 3 upper jejunum tumors from 44 patients were investigated. All tumors were tested immunohistochemically for gastroenteropancreatic hormones and general endocrine cell markers. Twenty-eight of the 45 tumors (62%) proved to be gastrin cell tumors, with (12 cases) or without (16 cases) associated Zollinger-Ellison syndrome. Zollinger-Ellison syndrome was part of type 1 multiple endocrine neoplasia syndrome in 3 cases. Twenty-three of the 28 gastrin cell tumors (82%) were from proximal duodenum, 2 were from the second part of the duodenum, and 3 were from the upper jejunum. Seven cases were somatostatin cell tumors, 6 of which were from the ampullary region; 5 cases were associated with biliary tract disease and 2 with associated cutaneous neurofibromatosis. Four ganglioneuromatous paragangliomas, from the ampullary region or nearby duodenum, showed somatostatin cells, coupled with pancreatic polypeptide cells in 2 cases. Two serotonin-producing argentaffin carcinoids were also identified. In addition to the main cell type, 30 tumors showed one or more, usually minor, cell populations producing somatostatin, serotonin, cholecystokinin, pancreatic polypeptide, insulin, neurotensin, or the alpha chain of human chorionic gonadotropin. Only 3 tumors lacked hormone immunoreactivity. Some correlation has been noted between histological structure and hormone content of tumor cells, with prevalence of broad gyriform trabeculae and vascular pseudorosettes among gastrin cell tumors, tubuloacinar patterns among somatostatin cell tumors, thin parallel trabeculae among PP cell growths, and a solid nest pattern among argentaffin carcinoids. Deep infiltration of the intestinal wall was observed in 22 tumors, 6 of which also had metastases to local lymph nodes. All metastatic cases were among ZES tumors or ampullary somatostatin cell tumors. Ganglioneuromatous paragangliomas and nonfunctioning gastrin cell tumors had essentially benign behavior, even when involving deep strata of the intestinal wall. Post operative follow-up study of 36 cases, including all metastatic tumors, showed no evidence of tumor-related death or progressive tumor disease.

Postprandial exocrine pancreatic function during long-term treatment with the somatostatin analogue SMS 201-995 in acromegalic patients

Long-term treatment with the somatostatin analogue SMS 201-995 (SMS) might impair exocrine pancreatic function, secretion of cholecystokinin (CCK) and pancreatic polypeptide (PP), and pancreatic size. In five acromegalics on chronic treatment with SMS, we investigated postprandial 6-h urinary excretion of p-aminobenzoic acid (PABA) and p-aminosalicylic acid (PAS) after s.c. injection of 100 micrograms SMS or placebo and after ingestion of 2 mmol nBT-PABA and 2 mmol PAS. In the acromegalics, urinary PABA/PAS ratio (reflecting exocrine pancreatic function) after SMS was similar to that after placebo (P greater than 0.10) and higher than in healthy volunteers (n = 8, P = 0.05). The initial inhibition of plasma CCK secretion by SMS was cancelled during the 3rd h after the meal, whereas PP release remained completely abolished. Pancreatic size as measured by ultrasonography, was not reduced in seven acromegalics compared with 14 healthy volunteers. It is concluded that despite a blunted release of the trophic hormone CCK, long-term treatment with SMS 201-995 neither induces an abnormally small pancreas nor deterioration of postprandial exocrine pancreatic function in patients with acromegaly.

Somatostatin-producing duodenal carcinoids in patients with von Recklinghausen's neurofibromatosis. A predilection for black patients

Eight patients with von Recklinghausen's disease (VRD) and duodenal carcinoids are presented. Seven patients were black, and one white. Six of the eight were women. The presenting symptom was either jaundice or abdominal pain. All tumors were located in the second portion of the duodenum, and three were multiple. Associated tumors other than neurofibromas included multiple leiomyomas, meningioma, neurofibrosarcoma, and prostatic sarcoma. Seven tumors had psammoma bodies, and in three they were numerous. Somatostatin-positive cells were demonstrated in all cases. Two tumors had spread to regional lymph nodes at the time of surgery. There appears to be a predilection for black patients among those with VRD and duodenal carcinoids.

Anatomic distribution of pancreatic endocrine tumors

Pancreatic endocrine tumors are grouped together by their common histologic, cytochemical, and ultrastructural features. Although useful conceptually, this paradigm has been unable to predict the anatomic location of different tumor types. Successful surgical excision of these tumors would be facilitated by an improved understanding of their anatomic distribution. Based on the available data, a bimodal distribution of pancreatic endocrine tumors was identified. Cluster 1 (gastrinomas, pancreatic polypeptide (PP)-secreting tumors, somatostatinomas) had 75% of tumors to the right of the superior mesenteric artery, whereas cluster 2 (insulinoma, glucagonoma) had 75% of tumors to the left of the superior mesenteric artery (p less than 0.05). This distribution is similar to that distribution predicted based on the volume density of the corresponding islet cells for insulinoma, glucagonoma, and PP-secreting tumors, but not for somatostatinoma. These findings suggest that pancreatic endocrine tumors are derived from similar cytologic precursors as pancreatic islet cells, and their distribution may be a consequence of embryologic development from either the ventral (cluster 1) or dorsal (cluster 2) pancreatic buds.

Duodenal gangliocytic paraganglioma with lymph node metastasis in a 17-year-old boy

A case of duodenal gangliocytic paraganglioma (DGP) in a 17-year-old boy is presented. In this case a lymph node in the peripancreatic region was involved by a metastatic tumor. A review of the literature on DGP indicates that this case represents the youngest patient and is the second case of DGP with metastasis. Immunohistochemical staining for neuron-specific enolase (NSE), neurofilament (NF), pancreatic polypeptide, and somatostatin showed positive results for epithelioid and ganglion-like cells, whereas spindle cells showed immunoreactivities for S-100 protein, NSE, and NF. The histogenesis of DGP is discussed.

Ectopic endocrine pancreatic tumour simulating splenic angiosarcoma

A case of ectopic endocrine pancreatic tumour that had developed within the spleen of a 46-year-old man is reported. The tumour was highly vascularized through the splenic artery, angiographically simulating an angiosarcoma. The histological pattern was typical of an endocrine tumour, and its nature was confirmed by a positivity for keratin, chromogranin A and somatostatin. Foci of atrophic pancreatic tissue were detected in the tumour capsule.

Obstructive pancreatitis: unusual causes of chronic pancreatitis

Fifty-eight consecutive surgical pancreatic resections for chronic pancreatitis were examined. Eight cases were identified with obstructive pancreatopathy; all underwent pancreato-duodenectomy. Histological examination revealed that obstruction in three cases was due to duodenal wall cysts, and in two patients it was associated with pancreas divisum (the accessory papilla was obstructed by a neuroendocrine tumour in one case and by ectopic pancreatic tissue in the other). One case each was due to obstruction of an anomalous duct by vegetable matter, to segmental pancreatitis, and to an intraductal carcinoma. Obstructive pancreatitis has many causes and diligent pre-operative assessment is required as surgical resection may be beneficial. Special efforts should be made to identify ductal anomalies, duodenal cysts, ectopic pancreatic tissue, and small ampullary tumours of exocrine and endocrine origin in order to define the aetiology of pancreatitis.

A polypoid duodenal somatostatinoma. A case report

A case of a pedunculated, polypoid duodenal somatostatinoma is presented. The clinical and pathologic aspects of duodenal somatostatinomas are summarized and briefly discussed.

Somatostatinoma: a case report and review of the literature

Somatostatinomas are rare endocrine tumors that were first described in 1977. In addition to the present case report, there have been 31 cases reported in the literature. We have reviewed the literature to integrate the symptoms, physical findings, diagnostic tests, treatment, and length of survival of these patients. Although the symptoms that occurred in the majority of cases were those that are seen in most patients with intra-abdominal neoplasms, symptoms relating to the presence of excess circulating somatostatin--diabetes, maldigestion, and cholelithiasis--were frequently seen. Physical findings and the results of diagnostic tests were usually nonspecific. The majority of the patients underwent radical surgical procedures (Whipple procedure or pancreatic resection). The pancreas was the most frequent site of involvement (21/31 cases), but primaries in the duodenum, ampulla of Vater, cystic duct, and jejunum have been described as well. Metastases were most frequently seen in the liver and lymph nodes. Chemotherapeutic agents were administered to 10 patients, usually as adjuvant therapy, and appear to be useful in treating recurrent and metastatic disease. The one-year survival of these patients is 48%, which is better than that for patients with carcinoma of the pancreas or biliary tree. Therefore, it is important that the diagnosis of somatostinoma be made so that the patient may be treated accordingly and followed by serial somatostatin levels for evidence of metastasis or recurrent disease.

Somatostatinoma of Vater's papilla and of the minor papilla

Two cases of somatostatinomas of the major and minor papilla are reported. The tumors were characterized by solid trabecular and tubular arrangements of tumor cells and in one case by the presence of microvilli and psammoma bodies. The tumor cells contain many amine precursor uptake and dicarboxylation (APUD)-granules with a diameter of 300 to 500 nm and low electron density. Immunoperoxidase stain showed intense staining only for somatostatin and low density of neuron-specific enolase. Those tumors either resulted from pluripotent endocrine cells or from D-cells of the mucosa or glands of the papilla.

Duodenal gangliocytic paragangliomas: a study of 10 cases with immunocytochemical neuroendocrine markers

Ten cases of duodenal paraganglioma were studied by conventional histologic and immunocytochemical techniques at both light and electron microscopic levels. Histologically, mixtures of epithelial, ganglion, and spindle cells were seen. In all of the cases immunoreactivity for neuron-specific enolase (NSE) and protein gene product (PGP) 9.5 was seen in each component. Pancreatic polypeptide immunoreactivity was detected in eight cases, mainly in epithelial cells. Somatostatin immunoreactivity was present in epithelial and ganglion cells in nine cases. In seven cases immunoreactivity for neurofilaments, a marker for neurons, was seen in ganglion and spindle cells. However, immunoreactivity for chromogranin, a protein found in endocrine storage granules, was found in only two cases, and the staining was confined to well-granulated epithelial cells. The spindle cells were immunostained only for neuronal markers, NSE and neurofilaments, and the glial marker S-100 protein.

Duodenal and ampullary carcinoid tumors. A report of 12 cases with pathological characteristics, polypeptide content and relation to the MEN I syndrome and von Recklinghausen's disease (neurofibromatosis)

Twelve duodenal carcinoid tumours are presented, 4 of them located in the ampulla. Symptoms included the Zollinger-Ellison syndrome (4 patients), the carcinoid syndrome (1 patient), mechanical obstruction (3 patients), bleeding (1 patient) and abdominal pain (1 patient). Two further tumours were detected by chance. Three patients with the Zollinger-Ellison syndrome had additional endocrine tumours characteristic of the MEN I syndrome. In 2 of them the duodenal carcinoids were of very small size and were multiple. They were observed in close proximity to focal areas of endocrine cell hyperplasia. Immunohistochemical investigations showed gastrin and somatostatin to be the predominant polypeptide hormones produced by these tumours. No somatostatinoma syndrome was encountered. In half of our cases additional production of insulin, VIP or even calcitonin in smaller amounts was found. Two of our patients had cutaneous manifestations of von Recklinghausen's disease and in both of them the carcinoid was located in the ampulla. One of these patients also had a pheochromocytoma.