Carcinoid tumors of the pancreas: CT findings

Carcinoid syndrome from a carcinoid tumor of the pancreas without liver metastases: A case report and literature review

A carcinoid tumor of the pancreas (CTP) is a rare pancreatic neoplasm, and usually presents with carcinoid syndrome (CS). CS consists of the classic symptom triad of cutaneous flushing, diarrhea and valvular disease, and occurs in the majority of patients with liver metastases. In the present study, the patient presented with symptoms of CS. A diagnosis of CTP with CS was suspected due to high levels of urine 5-hydroxyindolacetic acid, and this was confirmed by a fine-needle aspiration biopsy. Computed tomography showed extended lymphadenopathy, but no liver metastases. The patient was managed conservatively with octreotide long acting repeatable. To the best of our knowledge, this is the second literature case of CS associated with CTP without liver metastases.

Uncommon presentations of common pancreatic neoplasms: a pictorial essay

Pancreatic neoplasms are a wide group of solid and cystic lesions with different and often characteristic imaging features, clinical presentations, and management. Among solid tumors, ductal adenocarcinoma is the most common: it arises from exocrine pancreas, comprises about 90% of all pancreatic neoplasms, and generally has a bad prognosis; its therapeutic management must be multidisciplinary, involving surgeons, oncologists, gastroenterologists, radiologists, and radiotherapists. The second most common solid pancreatic neoplasms are neuroendocrine tumors: they can be divided into functioning or non-functioning and present different degrees of malignancy. Cystic pancreatic neoplasms comprise serous neoplasms, which are almost always benign, mucinous cystic neoplasms and intraductal papillary mucinous neoplasms, which can vary from benign to frankly malignant lesions, and solid pseudopapillary tumors. Other pancreatic neoplasms, such as lymphoma, metastases, or pancreatoblastoma, are rarely seen in clinical practice and have different and sometimes controversial managements. Rare clinical presentations and imaging appearance of the most common pancreatic neoplasms, both solid and cystic, are more frequently seen and clinically relevant than rare pancreatic tumors; their pathologic and radiologic appearances must be known to improve their management. The purpose of this paper is to present some rare or uncommon clinical and radiological presentations of common pancreatic neoplasms providing examples of multi-modality imaging approach with pathologic correlations, thus describing the histopathological bases that can explain the peculiar imaging features, in order to avoid relevant misdiagnosis and to improve lesion management.

Serotonin-producing enterochromaffin cell tumors of the pancreas: clinicopathologic study of 15 cases and comparison with intestinal enterochromaffin cell tumors

OBJECTIVES

Serotonin-producing tumors of the pancreas are rare endocrine neoplasms composed of enterochromaffin (EC) cells that have been mainly described in the literature as case reports. This study analyzes the clinicopathologic features of a series of pancreatic EC cell neoplasms and their similarities to and differences from intestinal EC cell tumors.

METHODS

The morphological, immunohistochemical, ultrastructural, and fluorescent in situ hybridization features of 15 pancreatic and 20 intestinal serotonin-producing neoplasms were compared. In addition, we reviewed the literature on pancreatic serotonin-producing tumors to better understand the clinicopathologic features of this rare tumor type.

RESULTS

The lack of substance P and acidic fibroblast growth factor immunoreactivity; the low immunohistochemical expression of CDX2, vesicular monoamine transporter 1, connective tissue growth factor, and prostatic acid phosphatase; the lack of S100-positive sustentacular cells; the strong expression of vesicular monoamine transporter 2; and peculiar ultrastructural features characterize pancreatic EC cell tumors and differentiate them from intestinal ones, although both categories show similar chromosome 18 cytogenetic alterations. The review of the literature indicates that pancreatic functioning tumors associated with the carcinoid syndrome arise in younger patients and are larger, more frequently malignant, and more aggressive neoplasms than pancreatic nonfunctioning ones.

CONCLUSIONS

Pancreatic EC cell tumors show several different morphological features compared with related intestinal tumors despite similar cytogenetic alterations on chromosome 18.

Carcinoid tumors of the pancreas: dynamic CT and MRI features with pathological correlation

BACKGROUND

Carcinoid tumor of the pancreas is rare, and there are few reports that described its CT or magnetic resonance imaging (MRI) findings. We describe the characteristic CT and MRI findings in four cases of carcinoid tumor of the pancreas.

METHODS

Radiologic and pathologic features were analyzed in four patients. All patients underwent triple-phase dynamic CT and MRI.

RESULTS

The tumor size in the four cases ranged 15-20 mm and intratumoral calcification was detected in one case. On triple-phase dynamic CT, the peak enhancement of the tumors was seen at the arterial dominant phase in three cases; the remaining one was at the portal venous phase with prolonged contrast-enhancement effect. The tumors showed low to high signal intensity on T2-weighted images. Dilatation of the main pancreatic ducts (MPDs) distal to the tumors was seen in three cases, in which tumor invasion into the MPDs was pathologically confirmed. Furthermore, the tumors having mild to severe fibrosis pathologically invaded into the peripancreatic lymphatics or nerves.

CONCLUSION

It would be characteristic of carcinoid tumor of the pancreas to be well enhanced at the arterial dominant phase on dynamic CT, and to highly invade into the MPDs and the peripancreatic lymphatics or nerves.

Pancreatic carcinoid tumor with obstructive pancreatitis: multislice helical CT appearance: case report

Carcinoid tumor of the pancreas is rare. Moreover, obstructive pancreatitis secondary to a pancreatic carcinoid tumor is extremely rare. We report a case of pancreatic carcinoid tumor in a 50-year-old male who presented with pancreatitis. On multislice helical computed tomography, the main pancreatic duct was obstructed by a small round tumor, and the main pancreatic duct proximal to the tumor was dilated. The correlation between the main pancreatic duct and the tumor was well depicted on minimum intensity projection image. This is the first report of multislice helical computed tomorgraphic and minimum intensity projection image findings of a pancreatic carcinoid tumor presenting with pancreatitis.

Co-existent chronic pancreatitis and pancreatic neuroendocrine tumor. Case report and review of the literature

BACKGROUND

Few reports exist in the literature regarding neuroendocrine tumors either presenting as, or associated with, chronic pancreatitis. We report a case of chronic pancreatitis with a coexisting neuroendocrine tumor (gastrinoma) of the body of the pancreas. The available literature is reviewed.

METHODS

Patient data including history, surgical procedure, histology and radiology investigations were collected and summarized. A Medline search using the key words 'pancreatitis' and 'neuroendocrine tumors' was performed for the years 1966-1999. Cited references in the relevant papers not listed in Medline databases were also evaluated.

RESULTS

A 64-year-old female patient was operated on for unclear cystic lesions in the head and tail of the pancreas. Intraoperatively, a gastrinoma was incidentally discovered in the body of the pancreas. It did not appear to be obstructing the main pancreatic duct. The patient underwent a distal pancreatectomy with pancreatico-jejunostomy. Four months postoperatively, she is doing well with no signs of tumor recurrence. The Medline search revealed 125 publications, of which only 17 dealt with either acute or chronic pancreatitis associated with neuroendocrine tumors. When all available data were included, there were 26 cases of neuroendocrine tumors associated with acute pancreatitis. Additionally, 11 cases were associated with chronic pancreatitis, of which only 3 appear to be merely coexistent with chronic pancreatitis without an apparent cause-and-effect relationship between these two entities.

CONCLUSION

We report the rare co-existence of chronic pancreatitis and a neuroendocrine tumor (gastrinoma) of the pancreas. The cause-and-effect relationship between neuroendocrine tumors of the pancreas and chronic pancreatitis continues to be uncertain. However, when the etiology of chronic pancreatitis is unclear, rare neuroendocrine tumors of the pancreas might be considered. Questions remain with regard to the potential role of chronic pancreatitis in the pathogenesis of pancreatic neuroendocrine tumors.

[Pancreatic carcinoid]

Carcinoid tumours arise from argentaffine cells or from a primitive stem cells which may differentiate into anyone of a variety of adult endocrine-secreting cells. Carcinoid tumour of the pancreas is a very rare tumour with less than 50 cases reported in world literature. In literature it is denoted "pancreatic serotoninoma" or "serotonin-producing pancreatic tumour". Due to its rarity the tumour is an unusual cause of carcinoid syndrome. As the carcinoid tumour of the pancreas does not always causes carcinoid syndrome its absence does not necessarily exclude the existence of the tumour. The tumour is frequently malignant. Over 50% of patients have metastases at the time of surgery. This is the reason why radical surgery is not possible in a number of patients. Excisional surgery offers the best chance for recovery or long term survival. We report on a 57-year-old woman with carcinoid syndrome caused by malignant carcinoid tumour of the head of the pancreas without liver or other distant metastases; it was successfully excised with pylorus preserving cephalic duodenopancreatectomy (after Longmire-Traverso) and radical lymphadenectomy. The diagnosis was established on the basis of histologic and immunohistochemical findings. The patient is symptom free for more than eight months.

Carcinoid tumors of the pancreas. Status report based on two cases and review of the world's literature

CONCLUSION

The diagnosis of a pancreatic carcinoid should be based on the measurement of serotonin in serum or its demonstration in the tumor and/or by the measurement of its derivative (5-HIAA) in urine. Carcinoid of the pancreas is a rare but definite entity; usually having metastasized by the time of diagnosis. The term "serotonin-producing tumor of the pancreas" has been suggested as an alternative designation for "pancreatic carcinoid."

BACKGROUND

The literature on carcinoid tumors of the pancreas is confusing because much of it preceded the development of the more specific immunological, chemical and staining techniques currently available.

METHODS

43 case reports were collected from the world's literature, based on a demonstrable pancreatic neuroendocrine tumor plus a positive finding of at least one of the following without another dominant hormone being demonstrated: elevation of 5-Hydroxytryptamine (5-HT) (serotonin) in the serum or detected in tumor tissue, and/or elevation of 5-Hydroxyindole acetic acid (5-HIAA) in the urine. In addition to these two hormone-specific assays, information was collected on the silver-staining properties of the tumor; properties which have traditionally been associated with carcinoid tumors. Positive silver staining in tumor cells (argyrophilic and/or argentaffin reaction) is strongly indicative of the carcinoid tumor but the findings are less specific than the hormone assays and immunohistologic stains.

RESULTS

In this review of 43 cases, including two current ones, the pancreatic carcinoid tumor has the following important features: 1. It is a rare tumor that is usually diagnosed late when the tumor is large and has metastasized. Thirty-eight (88.4%) have been malignant. They are, therefore, associated with a high incidence of the "carcinoid syndrome." 2. To date, prognosis in therapy is poor, based on delayed diagnosis, a resultant low incidence of resectability, and an uncertain duration of survival after resection. 3. Pancreatic carcinoid tumors remain difficult to differentiate from other endocrine tumors. The measurement of urinary 5-HIAA excretion or the demonstration of elevated serotonin level in the tumor or in serum is essential to its distinction. Silver staining of the tumor, although of historic importance, has been superceded by the hormone-specific studies. 4. To distinguish it from other endocrine tumors of the pancreas, the terms "pancreatic serotoninoma" or "serotonin-producing tumor of the pancreas" have been suggested as possible alternatives. Its growth characteristics may be related more to its cell of origin than to its extent of hormone secretion. Not all of the tumors result in recognizable hyperserotoninemia.

Pancreatitis associated with neuroendocrine (islet cell) tumors of the pancreas

BACKGROUND

The association of pancreatitis with neuroendocrine tumors of the pancreas is uncommon, whereas its association with exocrine pancreatic cancer is well recognized. Since the latter, but not the islet cell tumor, is thought to originate within the ductal system, it is not surprising that pancreatitis is less likely to result from the islet cell tumor. The senior author has recently noted that the first recognizable indication of an islet cell carcinoma may be one or more discrete attacks of acute pancreatitis.

METHODS AND RESULTS

Acute pancreatitis, resulting from an islet cell tumor, has been observed in five patients, in one of whom it had become chronic. In four of the patients, the tumor was malignant. A review of the English language literature reveals 14 such patients with pancreatitis, and 2 others have been noted in other languages (a total of 21 patients). The tumor was malignant in 15 of the 21 patients (71%). Although the development of pancreatitis was found to result from the obstruction of the duct in most patients, at least three seemed unrelated. In 12 of 21 cases (57%), an acute attack of pancreatitis, usually recurrent, was the initial syndrome, in contradistinction to pancreatitis resulting from exocrine tumors, which has usually been chronic in nature.

CONCLUSION

Pancreatitis, particularly acute pancreatitis, may result from an islet cell tumor. Although unusual, its occurrence may be the first signal of the presence of the tumor. In our experience, obstruction of the pancreatic duct by the islet cell carcinoma appears to be the important etiologic factor.