Streptozocin alone compared with streptozocin plus fluorouracil in the treatment of advanced islet-cell carcinoma

Endocrine tumours of the pancreas: review and recent advances

Pancreatic endocrine tumours (PET) are rare but nonetheless important to recognize and treat in a timely fashion. Significant morbidity occurs due to excess secretion of hormones, with all of the PET having some degree of malignant potential. Surgeons must plan directed operative strategies to deal with these tumours and be prepared to undertake aggressive palliative debulking resections if indicated. Somatostatin receptor scintigraphy and endoscopic ultrasound have been particularly helpful in both localizing and staging patients with PET. Other important advances in management include the use of long-acting somatostatin analogues to inhibit hormonal secretion and tumour growth. The possibility of multiple endocrine neoplasia type 1 (MEN-1) should be considered in any patient with a PET. The present article will review the various classes of PET, describe MEN-1 in relation to PET and examine advances in imaging and localization. The role of surgery for PET is also discussed in the present review.

Phase II trial of dacarbazine (DTIC) in advanced pancreatic islet cell carcinoma. Study of the Eastern Cooperative Oncology Group-E6282

BACKGROUND

A phase II study of dacarbazine (DTIC), was conducted to determine the response rate, duration of response, toxicity and overall survival of patients with advanced pancreatic islet cell tumors.

PATIENTS AND METHODS

Fifty patients with advanced pancreatic islet cell tumors, having progressive symptoms or evidence of rapidly advancing disease were entered on this study. DTIC was given by IV infusion at a dose of 850 mg/m2, over 60-90 minutes, repeated every four weeks.

RESULTS

The response rate was 33% in 42 patients who had measurable tumor, and 34% in the 50 patients (90% confidence interval (90% CI): 23%-47%). The majority of the responses were seen in patients without prior chemotherapy. Median overall survival was 19.3 months. There were two lethal toxicities on the study, one septic shock and one myocardial infarction. Grade 4 toxicities were, hematological (5 patients), sepsis, neurological (depression and paranoid behavior) and bleeding (1 patient each). The most common toxicity was vomiting, grade 3 in 13% of patients.

CONCLUSIONS

DTIC has activity in advanced previously untreated pancreatic islet cell tumors.

Islet cell tumors of the pancreas: the medical oncologist's perspective

Islet cell tumors of the pancreas are rare, indolent, neuroendocrine tumors. Approximately 50% of the patients diagnosed with these tumors present with symptoms related to various biologically active hormones that are secreted by these neoplasms. Currently, the only curative treatment for islet cell tumors is complete surgical resection. Management of metastatic disease is conservative. Initial treatment of these tumors includes expectant observation and medical management of symptoms with clinical monitoring and serial CT scans to assess tumor growth. Patients with rapidly progressive disease, with local symptoms caused by tumor bulk, or with uncontrolled symptoms related to hormone secretion require more aggressive medical or surgical intervention. The somatostatin analogue octreotide may help control hormone secretion and stabilize tumor growth. Patients refractory to octreotide with tumor predominantly in the liver are potential candidates for mechanical ablative techniques, such as hepatic arterial embolization. Radiofrequency ablation and cryosurgical techniques may also be useful, although specific data are limited. Surgical resection of metastatic disease may offer palliative relief of symptoms related to hormone secretion in carefully selected patients. Chemotherapy may be used for palliation when ablative techniques have failed or when significant extrahepatic disease is present. Streptozicin-based combinations remain the first line standard, but major objective responses are less common than had been previously thought. Because of the overall modest success of current chemotherapeutic regimens, patients with advanced disease in need of treatment should be encouraged to enroll in clinical trials testing newer antineoplastic agents or newer treatment strategies.

Transplantation for liver and biliary cancer

The early survival of patients transplanted for liver and biliary cancer is excellent, but the overall mid- to long-term survival is poor. In an era of severe donor organ shortage, it is not justified to allocate donor liver to patients with a suboptimal outcome. Patients with non-resectable hepatocellular carcinoma in a non-cirrhotic liver should not be assigned to liver transplantation. Although patients with the fibrolamellar variant have a somewhat better outlook, they are still likely to recur, and the young age of many of these patients is likely to overwhelm any rational approach. The results of transplantation for early-stage hepatocellular carcinoma in a cirrhotic liver are similar to those achieved with benign disease. The inclusion of such cases as a group is justified, but attempts should be made to resect tumors whenever possible and to not assign the entire group to transplantation as the first and only option. The value of pre- and postoperative adjuvant therapy for this group is still under debate, but the present waiting period is so long that some form of therapy to slow growth and prevent dissemination of tumor cells is probably required. The results following transplantation for cholangiocarcinoma can only be regarded as dismal, and the diagnosis of cholangiocarcinoma is a contraindication for the procedure. Liver transplantation has a definite place in the treatment of epithelioid hemangioendothelioma and unresectable chemo-responsive hepatoblastoma when confined to the liver, and in a limited number of metastatic neuroendocrine tumors.

Multiple endocrine neoplasia type 1

Combined clinical and laboratory investigations of MEN-1 have resulted in an increased understanding of this disorder, which may be inherited as an autosomal dominant condition. Defining the features of each disease manifestation in MEN-1 has improved patient management and treatment and has facilitated a screening protocol. Application of the techniques of molecular biology has enabled the identification of the gene causing MEN-1 and the detection of mutations in patients. The protein encoded by the MEN1 gene has been shown to be involved in the regulation of JunD-mediated transcription, but much still remains to be elucidated. Recent advances permit the identification of mutant MEN1 gene carriers who are at a high risk for this disorder and who require regular and biochemical screening to detect the development of endocrine tumors.

Pancreatic vasoactive intestinal polypeptide-oma as a cause of secretory diarrhoea

A 42-year-old woman presented with a 4-year history of worsening diarrhoea that was watery, profuse and confirmed to be secretory in nature. She had tested positive for phenolphthalein on urinary laxative screening but continued to deny laxative usage. Her vasoactive intestinal polypeptide (VIP) level was subsequently found to be markedly elevated. Despite a normal abdominal ultrasound, a computed tomography scan revealed a 5-cm pancreatic tail mass. Octreotide scanning was used to exclude metastatic disease and she went on to have surgical removal of a localized pancreatic vasoactive intestinal polypeptide-oma which resulted in the complete resolution of her diarrhoea.

[Drug therapy of endocrine neoplasms. Part II: Malignant gastrinomas, insulinomas, glucagonomas, carcinoids and other tumors]

BACKGROUND

The thyroid gland and the adrenal glands are the most common sites of endocrine carcinomas (see Part I of this review, Med Klin 2000;95: 20-5, Nr. 1). Less frequent are endocrine malignancies of the gastrointestinal tract (gastrinomas, insulinomas, glucagonomas, carcinoids and others).

TREATMENT

Because of the rarity and missing prospective studies as well as radiotherapy and chemotherapy resistance of these tumors, generally accepted conventional therapy guidelines for these endocrine carcinomas do not exist. Surgery and radionucleotide treatment should be considered as first line therapy. Somatostatin analogs (octreotide) are frequently used as well. Chemotherapy is usually not effective. Common substances are streptozotocin, 5-fluorouracil, doxorubicin, dacarbazine and cyclophosphamide.

Metastatic jejunal VIPoma: beneficial effect of combination therapy with interferon-alpha and 5-fluorouracil

The VIPoma syndrome is rare. It is usually caused by a neuroendocrine tumor located in the pancreas. Somatostatin analogs and interferon-a can be helpful in the symptomatic control of the disease, but the efficacy of chemotherapy in metastatic disease is limited. We report the case of a 32-yr-old patient who had a primary intestinal VIPoma with peritoneal carcinomatosis and hepatic metastases. Somatostatin analogs and conventional chemotherapy regimens were not effective on VIPoma syndrome and tumor progression. The combination of 5- fluorouracil and interferon-alpha was associated with a major clinical improvement and tumor regression. Further investigations should evaluate the place of such a combination as a first line treatment for patients with metastatic neuroendocrine tumors.

Neuroendocrine gastrointestinal tumors--a condensed overview of diagnosis and treatment

Neuroendocrine gut and pancreatic tumors are rather rare malignant diseases which has gained increased attraction through the last decennium, possibly through development of new diagnostic and therapeutic methods. Histopathology demonstrating the common neuroendocrine features of these tumors has been the diagnostic corner stone for long, but today it should be supplemented with information about the tumor biology. An excellent biochemical marker which is easy to analyze in serum or plasma is chromogranin A, which is a glycoprotein that is stored and released from neuroendocrine cells. This marker can be used for diagnosis and follow-up of the patients. Somatostatin receptor scintigraphy has been one of the most important diagnostic tools for staging of the disease and also indicating sensitivity to treatment with somatostatin analogues. It is a general agreement that almost every patient should be subjected to this procedure before or during the treatment course. From the therapeutic point of view, surgery is nowadays more extensive aiming at reducing the tumor mass in patients who could not be cured by surgery alone. Other means of tumor reduction is liver dearterialization by embolization with starch spheres. The medical treatment of neuroendocrine tumors has made a real break through with the introduction of somatostatin analogues, particularly octreotide, and today most of the hormonally related symptoms can be controlled by this kind of treatment. Somatostatin analogues have also shown to be inhibitors of tumor growth and the latest development is tumor targeted radioactive treatment with Ytrium or Indium labelled octreotide. Long-acting formulation of somatostatin analogues have come into clinical use and significantly improved quality of life for patients with neuroendocrine tumors. Other means of medical treatment are alpha interferons, which have shown particular effect in patients with midgut carcinoid tumors giving both biochemical and tumor responses. Chemotherapy such as streptozotocin plus 5-fluorouracil (5-FU) or doxorubicin is still considered as first-line treatment in malignant endocrine pancreatic tumors but is combined with concomitant somatostatin analogue treatment. In the future a multimodal treatment will further develop combining different agents and also somatostatin receptor subtype specific analogues will come into clinical use.

Prospective study of the clinical course, prognostic factors, causes of death, and survival in patients with long-standing Zollinger-Ellison syndrome

PURPOSE

The long-term clinical course of unselected patients with gastrinomas as well as other functional pancreatic endocrine tumors (PETs) in whom the excess-hormone state is controlled is largely unknown. To address this issue, patients with gastrinomas were assessed.

PATIENTS AND METHODS

Two hundred twelve patients with Zollinger-Ellison syndrome (ZES) were prospectively studied. All had controlled acid hypersecretion and were assessed yearly, with a mean follow-up period of 13.8+/-0.6 years (range, 0.1 to 31 years). Annual assessments of possible factors that might affect prognosis or treatment approaches were performed, such as those for tumor size and location; the presence, location, and extent of metastases; and the occurrence of ectopic Cushing's syndrome or another PET syndrome. Deaths were categorized as ZES-related or non-ZES-related and classified into different causes.

RESULTS

Thirty-one percent of patients died, all of non-acid-related causes. One half died of a ZES-related cause; they differed from those who died of non-ZES deaths by having a large primary tumor, more frequently a pancreatic tumor; lymph node, liver, or bone metastases; ectopic Cushing's syndrome; or higher gastrin levels. The extent of liver metastases correlated with survival rate. The presence of liver metastases alone only moderately decreased survival time; however, the additional development of bone metastases or ectopic Cushing's syndrome markedly decreased survival rate.

CONCLUSIONS

In ZES, gastrinoma growth is now the main single determinant of long-term survival, with one half of patients dying a gastrinoma-related death and none an acid-related death. Large primary tumors that are pancreatic in location, the development of liver metastases, (especially if associated with bone metastases or Cushing's syndrome), and the extent of liver metastases are all important prognostic factors. The identification of these factors allows the recognition of subgroups that can be used to tailor antitumor treatment approaches.

Necrolytic migratory erythema, first symptom of a malignant glucagonoma: treatment by long-acting somatostatin and surgical resection. Report of three cases

We report three cases of malignant glucagonoma with necrolytic migratory erythema as the first clinical symptom. Long-acting somatostatin analogue was the first step of a multimodal therapeutic strategy which included surgical resection of the primary tumour in every case. Liver metastases which were present in two patients were treated by hepatic arterial chemoembolization and systemic chemotherapy in one case and by liver resection for cytoreduction and hepatic arterial chemoembolization in another case. Skin lesions resolved in all three patients.

Doxorubicin, streptozocin, and 5-fluorouracil chemotherapy for patients with metastatic islet-cell carcinoma

Metastatic islet-cell carcinoma is considered to be a slow-growing tumor. Patients are considered for systemic chemotherapy only when they are symptomatic or have impending organ failure, and streptozocin has been the chemotherapeutic agent of choice for the treatment of this disease. Chemotherapy regimens that include streptozocin have shown a higher response rate and a longer duration of response when compared with streptozocin alone. This study evaluates the objective response, response duration, and survival in patients having metastatic islet-cell carcinoma treated with a combination of doxorubicin, streptozocin, and 5-fluorouracil (DSF). Between January 1993 and March 1996, 12 patients were treated with doxorubicin, 40 mg/m2 intravenous bolus on day 1; streptozocin, 400 mg/m2 intravenous bolus on days 1 through 5; and 5-FU, 400 mg/m2 intravenous bolus on days 1 through 5. Courses were repeated every 28 days. Patients were required to have measurable disease, a Zubrod performance status < or = 2, adequate renal and liver function, and a survival expectancy of at least 12 weeks. Six (54.5%) of 11 evaluable patients achieved a partial response (durations in months: 1+, 3.5+, 13+, 17, 22, 26+); one had a minor response, two had stable disease, and two had progressive disease. One patient was lost to follow-up. No complete responses were observed. The median response duration was 15+ months and the median survival 21+ months (range, 3 to 32.5 months). No grade 3 or 4 nonhematologic or hematologic effects were observed. The DSF regimen appears to have significant activity in patients who have metastatic pancreatic islet-cell carcinoma, and patient tolerance of the regimen is excellent, thus warranting further investigation.

Insulinoma: a review of current management

Insulinomas are a relatively rare tumour which occur predominantly in the pancreas. The majority of the tumours are benign, but have profound effects upon the patient. The diagnosis of insulinoma is often elusive, and the management may involve demanding surgery with a significant morbidity. In this review article, all clinical aspects of insulinomas are examined. Particular emphasis is placed on the myriad modes of presentation, and the methods used to localise the tumour pre-operatively. Medical, as well as surgical treatments are discussed and their role in the management of both malignant and benign tumours. Despite potential difficulties encountered in managing patients with this tumour, a large majority may be either cured or achieve useful palliation.

Vasoactive intestinal polypeptide-secreting tumours: biology and therapy

VIP-secreting tumours are rare, but they produce a dramatic clinical picture, the most prominent feature being profuse, watery diarrhoea and hypokalaemia. VIPomas are malignant and require sophisticated diagnostic and localization techniques in order to identify their presence. Delays in diagnosis are the rule rather than the exception. Improvements in the diagnosis of VIPomas appear to result in an increase in resectability rates. A definitive diagnosis is aided by the determination of plasma VIP concentrations through the use of sensitive radioimmunoassays. With heightened awareness of this syndrome, increasing numbers of patients can be identified and more effective treatments developed for the refractory and recurrent tumours.

Gastrointestinal endocrine tumours. Gastrinoma

Since the description of the Zollinger-Ellison syndrome in two patients in 1955, there have been significant advances in the understanding of its pathogenesis, natural history, relationship to multiple endocrine neoplasia type 1, diagnosis, methods of tumour localization and management. The main focus in treatment is now shifting from management of the gastric acid hypersecretory state which can now be controlled medically in almost every patient, to the management of the gastrinoma. Recent studies are beginning to provide insights into the natural history of gastrinomas, factors that are associated with invasiveness in some gastrinomas, defining the role of surgery in managing patients with different disease extents, or with MEN 1 and being able to provide insights into molecular abnormalities that may be important in their pathogenesis. In this article each of these advances is briefly reviewed with emphasis primarily on recent advances.

Gastrointestinal endocrine tumours: medical management

With the introduction of longer-acting somatostatin analogues symptomatic relief is easy to achieve in patients with functionally active endocrine tumours and will be further facilitated by still longer-acting formulations. The consequences of gastric acid hypersecretion in patients with Zollinger-Ellison syndrome can be prevented by all proton-pump inhibitors currently on the market. Despite the various antiproliferative strategies that have been offered to patients with metastatic disease, available data are controversial and, more importantly, are supported by few prospective and controlled studies. Most experts agree that surgery with curative extirpation of the primary in the absence of metastases and tumour debulking in metastatic disease should be intended wherever possible. Controversy concerns residual disease. According to our view, any further antiproliferative strategy should consider the growth characteristics and biology of a given tumour (Figure 4). In the case of rapid progression, chemotherapy should be offered if tumours originate from the pancreas or reveal an undifferentiated histology. In contrast, chemotherapy should not be offered to patients with well-differentiated non-functional or functional tumours (carcinoid syndrome) arising from the intestine. The same applies for patients with tumours with no or only slow growth within an given observation period of 3-12 months. These patients should be treated only symptomatically. Patients with tumours of slow progression might favourably respond to long-acting somatostatin analogues. We start with octreotide and offer patients not responding to octreotide monotherapy additional IFN alpha. If further tumour progression takes place, hepatic artery embolization is the next step (Figure 5) followed by chemotherapy, the latter in patients with tumours of pancreatic origin only. This strategy recognizes the severity of side-effects of the different therapeutic modalities and starts with octreotide because of its very few side-effects. Other groups start with chemoembolization followed by octreotide, alpha-interferon or its combinations (Ahlman et al, 1996). Ongoing studies will, it is hoped, answer the question of the ideal sequence of therapeutic strategies. Every available patient with metastasised gastrointestinal endocrine tumours should be included in one of the ongoing European multicentre trials.

Surgery and polychemotherapy of non-functional endocrine pancreatic tumors: a case report with a dramatic clinical response

Endocrine pancreatic tumors (EPT) are a rare clinical entity, representing 5% of all pancreatic tumors. Nonfunctional subtypes (NF-EPT) often present themselves at diagnosis in a locally advanced or metastatic stage. Therapeutic planning of these neoplasias is based on a multidisciplinary integration of surgery and medical treatments. The Authors describe a case of NF-EPT with massive metastatic spread after cytoreductive surgery, with impressive response to polychemotherapy with 5-fluorouracil, epirubicin and dacarbazine. The various options concerning chemotherapic treatment of these tumors are reviewed.

Neuroendocrine gastrointestinal tumours

Neuroendocrine gut and pancreatic tumours have provided a diagnostic and therapeutic challenge over the years. These rather slowly growing neoplasms have been assigned a good prognosis but when liver metastases are present the prognosis is not better than that of most other malignant tumours. Despite the development of improved diagnostic procedures many patients are still referred at a stage of the disease too late for surgical cure, at which time medical treatment is warranted. The diagnosis is based on histopathological diagnosis including silver stainings (Grimelius, Masson) and immunohistochemistry for chromogranin A and synaptophysin. Analysis of chromogranin A in the plasma is an important adjunct in the screening for various types of neuroendocrine gut and pancreatic tumours. About 80%-100% of patients with verified neuroendocrine gastrointestinal tumours have elevated circulating levels of this glycoprotein. Depending on clinical symptoms the chromogranin A analysis is supplemented by other peptide hormone analyses as well as urinary 5-HIAA for patients with midgut carcinoid tumours. In the past the localization procedures were based on CT, MRI and ultrasound investigations but in recent years somatostatin receptor scintigraphy (octreoscan) and endoscopic ultrasonography have significantly improved the diagnostic potential. Almost 80% of neuroendocrine gastrointestinal tumours present somatostatin receptor subtype 2 binding 111Indium-labelled octreotide which can be used for staging of the disease, and which also indicates whether or not somatostatin analogues can be used in the treatment of these tumours. Surgery is still a cornerstone in the treatment of neuroendocrine gastrointestinal tumours, even if the patients are beyond cure. Debulking procedures and bypassing operations are important for improving clinical condition and facilitating impending medical treatment, and during the past decade a more aggressive surgical approach has emerged. The medical treatment is based on chemotherapy, and the use of somatostatin analogues and alpha-interferons. Chemotherapy, in particular the combination of streptozotocin with 5-FU or doxorubicin, is still first-line treatment for most endocrine pancreatic tumours, while somatostatin analogues and alpha-interferons are considered first-line for classical midgut carcinoids. Chemotherapy and biotherapy can be combined in many patients, and changes from one medical treatment to another during the course of the disease is mandatory for control of the disease. It is important to realise that most patients with malignant tumours are not cured by medical treatment but that the disease can be controlled for extended periods of time. In the future it will be possible to individualize treatments on the basis of new information about such features of tumour biology as proliferation capacity, expression of adhesion molecules, and growth factors and their receptors.

Somatostatin analogue octreotide and inhibition of tumour growth in metastatic endocrine gastroenteropancreatic tumours

Antiproliferative treatment of patients with metastatic endocrine gastroenteropancreatic tumours (GEP) is based mainly on chemotherapeutic protocols whereby drug toxicity is a major handicap. Octreotide is the first choice in the control of hormone mediated symptoms. From retrospective and a few prospective studies it has been suggested that octreotide exhibits antiproliferative properties. The prospective German Sandostatin multicentre phase II trial investigated the effects of 200 micrograms octreotide thrice daily for one year on tumour growth and endocrine abnormalities in 103 patients. Octreotide treatment was continued in those patients responding to the drug until tumour progression occurred. In 28 of those with tumour progression during 200 micrograms thrice daily octreotide dose was increased to 500 micrograms thrice daily. The study sample consisted of 52 patients with computed tomography confirmed tumour progression and 13 patients with stable disease before octreotide treatment, whereas no preobservation period was available in 38 patients. Nineteen patients (36.5%) with computed tomography confirmed tumour progression experienced stabilisation of tumour growth lasting for at least three months. Median duration of stable disease was 18 months. At month 12, stable disease continued in 12 patients, declined after 24 months to nine patients, and after 36 months to five patients. Tumour regression has not been seen in this or other subgroups. In the subgroup with stable disease before octreotide, stable disease continued in 53.8% of patients over 12 months. Increase of octreotide dose to 500 micrograms thrice daily did not influence progression seen during the lower dose with the exception of one patient in whom tumour progression changed to stable disease. No association of tumour size response and patients' characteristics could be detected. The results suggest that octreotide inhibits tumour growth in patients with metastasised endocrine GEP tumours. The antiproliferative effect is, at least in some patients, longlasting. Currently, octreotide can only be recommended as an antiproliferative drug if patients with clearly progressive disease show stabilisation after treatment for three to six months.

The glucagonoma syndrome. Clinical and pathologic features in 21 patients

The glucagonoma syndrome is a rare disorder characterized by weight loss, necrolytic migratory erythema (NME), diabetes, stomatitis, and diarrhea. We identified 21 patients with the glucagonoma syndrome evaluated at the Mayo Clinic from 1975 to 1991. Although NME and diabetes help identify patients with glucagonomas, other manifestations of malignant disease often lead to the diagnosis. If the diagnosis is made after the tumor is metastatic, the potential for cure is limited. The most common presenting symptoms of the glucagonoma syndrome were weight loss (71%), NME (67%), diabetes mellitus (38%), cheilosis or stomatitis (29%), and diarrhea (29%). Although only 8 of the 21 patients had diabetes at presentation, diabetes eventually developed in 16 patients, 75% of whom required insulin therapy. Symptoms other than NME or diabetes mellitus led to the diagnosis of an islet cell tumor in 7 patients. The combination of NME and diabetes mellitus led to a more rapid diagnosis (7 months) than either symptom alone (4 years). Ten patients had diabetes mellitus before the onset of NME. No patients had NME clearly preceding diabetes mellitus. Increased levels of secondary hormones, such as gastrin (4 patients), vasoactive intestinal peptide (1 patient), serotonin (5 patients), insulin (6 patients, clinically significant in 1 only), human pancreatic polypeptide (2 patients), calcitonin (2 patients) and adrenocorticotropic hormone (2 patients), contributed to clinical symptoms leading to the diagnosis of an islet cell tumor before the onset of the full glucagonoma syndrome in 2 patients. All patients had metastatic disease at presentation. Surgical debulking, chemotherapy, somatostatin, and hepatic artery embolization offered palliation of NME, diabetes, weight loss, and diarrhea. Despite the malignant potential of the glucagonomas, only 9 of 21 patients had tumor-related deaths, occurring an average of 4.91 years after diagnosis. Twelve patients were still alive, with an average age follow-up of 3.67 years.

Drug therapy in metastatic neuroendocrine tumors of the gastroenteropancreatic system

Successful treatment of neuroendocrine tumor disease of the gastroenteropancreatic system requires a multimodal approach. Radical tumor surgery is required before other therapies are initiated. So far, only surgery has proven to be curative. If surgical intervention is not possible or a tumor-free state cannot be achieved, biotherapy with the somatostatin analogues octreotide or lanreotide should then be preferably carried out in patients with functional tumors. Interferon-alpha can alternatively be given. In patients with gastrinoma, therapy with proton pump inhibitors (e.g., omeprazol) is the initial treatment of choice. In patients with nonfunctional tumors, indication for treatment is only given in cases of documented tumor progress. In case of progressive tumor disease or functionality under the above-mentioned therapies, treatment with somatostatin analogues can be intensified by dose escalation or alternatively by a combination therapy with interferon-alpha and a somatostatin analogue. On the basis of the less favorable response of neuroendocrine foregut tumors to biotherapy, chemotherapy should be initiated after failure of biotherapy in documented tumor progression. A combination of streptozotocin and 5-fluorouracil, possibly combined with D,L-folinic acid, is the treatment of choice, considering the response and side effect rates. In case of predominantly anaplastic neuroendocrine tumors in advanced stages, good tumor response rates with a chemotherapeutic scheme consisting of cisplatin and etoposide can be achieved. Since the chemotherapy scheme is less effective in patients with midgut or hindgut tumors, chemoembolization of liver metastases should follow biotherapy. The response to chemoembolization may be increased by simultaneous systemic chemotherapy. Attention should always be paid to an adequate analgesic drug administration.

Islet cell tumors of the pancreas

Pancreatic endocrine neoplasms are a heterogeneous group of tumors that produce active hormones and result in distinct clinical syndromes. For the most part, they are malignant and require sophisticated diagnostic and localization techniques in order to identify their presence. Delays in diagnosis are the rule rather than the exception. Improvements in the diagnosis of gastrinomas and insulinomas appear to result in an increase in resectability rates. The widespread availability of intraoperative ultrasonography, as well as improved knowledge of the location of these tumors, has also had an impact on improved cure rates. With heightened awareness of these syndromes, increasing numbers of patients can be identified and more effective treatments developed for the refractory and recurrent tumors.

Octreotide treatment of carcinoid syndrome: analysis of published dose-titration data

BACKGROUND

Octreotide has proven therapeutically effective in carcinoid syndrome, but the rarity of carcinoid tumors has hampered detailed dose-ranging studies. This study analysed published dose-titration data on octreotide use in carcinoid patients to (a) investigate the relation between octreotide dose and efficacy and (b) establish octreotide dosing recommendations for maximum therapeutic benefit.

METHOD

An exhaustive, computer-assisted literature search for published articles employing octreotide to manage patients with carcinoid syndrome was performed using several databases. The relation between octreotide dose and efficacy in decreasing urinary 5-hydroxyindoleacetic acid (5-HIAA) levels, flushing and diarrhoea was analysed for seven dose ranges by pooling data from selected articles.

RESULTS

Analysis of data compiled from 62 published studies revealed that maximum effective therapeutic doses of octreotide effectively controlled symptoms in up to 93% of patients, and that increasing the dose of octreotide is associated with increased benefit with respect to control of flushing, diarrhoea and 5-HIAA levels.

CONCLUSIONS

We recommend starting octreotide therapy at 100 micrograms subcutaneously t.d.s. in patients with mild/moderate, non-life-threatening carcinoid syndrome. Since therapeutic response to octreotide varies markedly among patients, we recommend titrating the octreotide dose in increments of 50-100 micrograms every 8 h until adequate symptom control is achieved.

Neuroendocrine metastases of the liver

Neuroendocrine liver metastases are rare, yet they represent an entity that has attracted much attention lately. The protracted course of neuroendocrine tumors and the hormone origin of their typical incapacitating symptoms constitute a logical basis for well founded and bespoke treatment. Demonstration of the liver secondaries is best done by ultrasonography (US) and contrast-enhanced computed tomography (CT), which on the whole have replaced the invasive angiography techniques. By use of histochemical and molecular biologic methods the exact nature of the tumor can be typified in tissue samples obtained percutaneously, laparoscopically, or surgically. Localization of nonpalpable metastases of the liver is best done by intraoperative US. Surgical removal of liver metastases is curative in some cases and is usually effective in relieving the symptoms. Also, palliative debulking or cytoreductive surgery is often worthwhile as it offers a chance of prolonged survival and symptom relief. Similar benefits are achieved by ischemic therapy preferably by temporary dearterialization, which in our department is done on an outpatient basis using a specially designed (externally controlled) occluder applied during a single laparotomy that includes debulking when appropriate as well as cholecystectomy. Hormonal therapy with somatostatin analogs may be used as a single treatment or in combination with ischemic therapy. It has an ensured symptom-reducing effect, whereas its influence on tumor growth is unsettled. Lately similar effects have been ascribed to human leukocyte interferon. In conclusion the specific characteristics of neuroendocrine tumors and the available treatment arsenal favor an active treatment approach in patients who have developed liver metastases.

Pancreatic vipomas: spectrum of presentation and evolution of diagnostic and therapeutic modalities

Two patients are reported who presented with symptoms characteristic of a pancreatic vipoma. The necessity to measure more than one plasma VIP level for diagnosis, and the delay between the onset of illness and diagnosis is illustrated by both cases. Evidence suggests that vipomas are still under reported. The evolution of sophisticated diagnostic and therapeutic modalities over the twenty-five years separating both presentations is discussed.

Is there a prognostic difference between functional and nonfunctional islet cell tumors?

BACKGROUND

Pancreatic islet cell tumors are categorized as either functioning or nonfunctioning. Functioning islet cell tumors (FIT) elaborate a variety of hormones, producing dramatic symptoms, while the initial presentation of non-functioning islet cell tumors (NIT) is commonly an abdominal mass or symptom complex related to invasion of adjacent structures. As a result, NIT are purported to present at a later stage, with lower resectability rates, and an overall poorer prognosis, when compared to FIT. In addition, a number of reports have indicated that the incidence of NIT has increased significantly in recent years.

PATIENTS AND METHODS

Twenty-eight patients were studied retrospectively. All had islet cell tumors of the pancreas and were seen at the University of Nebraska Medical Center and affiliated Nebraska Methodist Hospital during a 19-year period.

RESULTS

There were 9 patients (32%) in the NIT group and 19 (68%) in the FIT group. The mean ages at presentation were 61 years for the NIT and 52 years for the FIT group. In the NIT group, all presented with either abdominal pain (n = 7) or jaundice (n = 2). In contrast, over 90% of the patients with FIT had symptoms referable to the specific hormone elaborated by the tumor. Primary tumor size for NIT was 4.1 +/- 0.7 cm versus 5.0 +/- 0.6 cm for the FIT group. No significant difference was found for NIT versus FIT with respect to the incidence of metastatic disease at presentation (44% versus 53%), resectability rate with curative intent (44% versus 53%), or disease-free survival at 2 years (67% versus 40%).

CONCLUSIONS

This series, in contrast to earlier reports, suggests that nonfunctioning islet cell tumors do not present at a more advanced stage, have lower resectability rates, or an overall poorer long-term prognosis when compared to functioning tumors.

Chemotherapy with dacarbazine and 5-fluorouracil in advanced medullary thyroid cancer

BACKGROUND

Experience with chemotherapeutic agents in the management of advanced medullary thyroid carcinoma (MTC) is limited and controversial. However, since MTC is a neuroendocrine neoplasm, we considered the possibility that cytotoxic drugs previously used in the treatment of these tumours could also have activity in MTC.

PATIENTS AND METHODS

Five patients (4 females and 1 male, aged 22-71 years) with locally advanced or metastatic MTC received 5 day intravenous courses of dacarbazine (DTIC) (250 mg/sqm) and 12 hour infusion 5-fluorouracil (450 mg/sqm), given every 4 weeks. Six cycles were administered to 4 patients and four to 1 patient.

RESULTS

Three partial responses lasting 9, 10+ and 8+ months were observed; one patient had stable disease and one progressive disease. Toxicity was acceptable with grade I thrombocytopenia and grade II leukopenia occurring in one patient, and grade II nausea and vomiting in four patients.

CONCLUSIONS

In our experience, treatment of advanced thyroid carcinoma with DTIC and 5-FU appeared to have significant activity and was well tolerated.

A phase II trial of alpha-interferon and 5-fluorouracil in patients with advanced carcinoid and islet cell tumors

BACKGROUND

5-Fluorouracil (5-FU) has shown modest single-agent activity in patients with carcinoid or islet cell tumors. Alpha interferon (alpha-IFN) has also shown modest single agent activity in these diseases, although biologic responses have been far more prevalent than have objective tumor regressions. The combination of alpha-IFN and 5-FU has demonstrated enhanced activity in several gastrointestinal malignancies.

METHODS

Twenty-one patients with advanced neuro-endocrine tumors (14 with carcinoid tumors, 7 with islet cell carcinomas) were treated with alpha-IFN and 5-FU in a Phase II study. 5-Fluorouracil was administered by intravenous bolus injection at an initial dose of 400 mg/m2/day for 5 consecutive days. After a 1-week break, 5-FU then was administered weekly by intravenous bolus at a dose of 750 mg/m2. Alpha interferon administration was begun on Day 1 of 5-FU at a daily dose of 3 x 10(6) U subcutaneously and continued for the duration of the trial.

RESULTS

Of the 14 carcinoid patients with carcinoid tumors, 1 experienced a partial response (7%; 95% confidence interval [CI] 0-20%) that lasted for 6 months. Eight of the patients with carcinoid tumors achieved stable disease for a median of 6 months (range, 2-10 months). One of the patients with islet cell tumors (14%; 95% CI 0-39%) achieved a partial response that persisted after 8 months; 4 patients with islet cell tumors had stable disease for a median of 13 months (range, 4-27+ months). Even at this relatively low dose of alpha-IFN, 14 of 21 patients required a dose reduction in the alpha-IFN (13 for fatigue, 1 for ataxia). Three patients experienced myelosuppression of greater than Grade 3, and three patients had diarrhea of greater than Grade 3. One patient experienced dose-limiting hand-foot syndrome.

CONCLUSIONS

These results suggest that the combination of 5-FU and alpha-IFN does not have any clear superiority over the individual agents alone; 5-FU appears to reduce patient tolerance of alpha-IFN when given on a daily schedule. Further investigations are needed to identify active agents in the treatment of neuroendocrine malignancies.

Clinical and biochemical effects in vivo of monoclonal antitumor antibody in Verner-Morrison's syndrome

BACKGROUND

Monoclonal antibodies have not been evaluated in metastasizing endocrine tumors, even though these lesions may induce severe morbidity of hormone excess in absence of considerable tumor burden.

METHODS

A murine monoclonal antibody of the IgG2a subtype was generated by immunization with dispersed tumor cells from an endocrine pancreatic carcinoma associated with liver and peritoneal metastases as well as a therapy-resistant Verner-Morrison's syndrome.

RESULTS

Immunohistochemical staining disclosed selective tissue reactivity of the antibody and conspicuous immunostaining on the surface of the tumor cells. Infusion of 100 mg antibody over 2 days into the common hepatic artery of the patient was accompanied by reduced diarrhea volume until death 6 weeks later and transient elevation of total plasma immunoreactivity for vasoactive intestinal peptide due to large molecular forms of the peptide. Postmortem examination demonstrated disappearance of peritoneal metastases as well as absence of immunostaining for the injected antibody and the transferrin receptor within residual hepatic tumors.

CONCLUSION

The results substantiate that symptomatic alleviation and perhaps interference with tumor cell mass may be obtained with monoclonal antibodies in patients with endocrine tumors and that the antiidiotypic immunoglobulin response may play a role herein.

An evaluation of human recombinant alpha interferon in patients with metastatic gastrinoma

BACKGROUND

Metastatic gastrinoma is becoming increasingly recognized in patients with Zollinger-Ellison Syndrome. The mean 5-year survival of these patients is < 20%. Chemotherapeutic regimens are of limited benefit. The aim of this study was to evaluate the use of interferon in these patients because a preliminary report suggested it might be effective.

METHODS

The efficacy and toxicity of interferon was assessed in 13 consecutive Zollinger-Ellison syndrome patients with liver metastases. Patients were treated with human recombinant alpha interferon (5 million IU, subcutaneously [SC]) daily and followed up at 3-month intervals with multiple imaging studies. At each follow-up, toxicity of therapy was assessed and fasting serum gastrin concentrations were obtained.

RESULTS

No patient showed a reduction in tumor size at any follow-up. One patient died after 2 months. At 6 months, six patients (46%) had stable tumor size in the liver, although new bone metastases developed in one patient. Three patients showed stable disease for up to 21 months. Changes in serum gastrin correlated with tumor response at 6 months. All patients developed some side effects of therapy. Thirty-one percent required dose reduction, and one patient (8%) had to have interferon therapy interrupted briefly.

CONCLUSIONS

These results fail to define a therapeutic role for interferon in the treatment of metastatic gastrinoma.

Review article: the management of Zollinger-Ellison syndrome

Awareness of the sometimes subtle features of Zollinger-Ellison syndrome is important in order not to miss the diagnosis. Immediately after initial diagnostic tests, the patient should be given antisecretory medication, while tests for the type of Zollinger-Ellison syndrome and tumour extent can be delayed. Acid output should be decreased to < 10 mmol/h to control symptoms and prevent complications. Histamine H2-antagonists remain the best available intravenous therapy but omeprazole is the most effective long-term oral therapy and has proved to be safe in nearly 10 years of continuous use. The management of the gastrinoma has changed in recent years since the discovery that the majority of gastrinomas arise outside the pancreas. Exploratory surgery with tumour resection is the treatment of choice in sporadic Zollinger-Ellison syndrome but there are few indications for surgery in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type-1. None of the available therapies for metastatic gastrinoma is very effective.

Flow cytometry and Zollinger-Ellison syndrome: relationship to clinical course

BACKGROUND

With successful means of controlling gastric acid secretion in patients with Zollinger-Ellison syndrome, the gastrinoma itself is becoming the major determinant of long-term survival. No methods have yet been described to predict which tumors will have more malignant courses thereby indicating which patients should undergo aggressive surgery or antitumor therapy. Because DNA analysis, using flow cytometry, has proved helpful in this regard in other tumors, the current study was designed to evaluate its utility in gastrinoma patients.

METHODS

Flow cytometry was performed on 81 paraffin-embedded gastrinoma specimens from 59 patients. Results were compared with preoperative patient characteristics, findings at surgery, and postoperative follow up.

RESULTS

Tumors were diploid in 54% of patients, near diploid in 15%, pure tetraploid in 0%, nontetraploid aneuploid in 25%, and multiple stem line aneuploid in 5%. All patients with multiple stem line aneuploid tumors had wide-spread metastases whereas all patients with nontetraploid aneuploid tumors had localized or regional disease. Median S phase percentage was 3.6. S phase percentages were higher in patients with widespread metastatic disease than in patients with localized or regional disease. Disease extent also correlated closely with fasting serum gastrin level. After removing this variable with logistic regression analysis, the significant correlation between disease extent and DNA analysis persisted.

CONCLUSIONS

DNA analysis of gastrinoma tissue specimens correlates independently with the extent of disease and may be useful in planning therapeutic strategies for patients with Zollinger-Ellison syndrome.

A phase II trial of carboplatin in patients with advanced APUD tumors

BACKGROUND

Chemotherapy remains inadequate for patients with carcinoid tumors, islet cell tumors, and medullary carcinomas of the thyroid. Carboplatin has shown activity in oat cell carcinoma of the lung, another tumor of neuroectodermal origin.

METHODS

Forty-two patients with advanced APUD tumors (20 carcinoid tumors, 9 islet cell carcinomas, 5 medullary carcinomas of the thyroid, and 9 neuroendocrine tumors of unknown primary site) were treated with carboplatin in a Phase II study.

RESULTS

Carboplatin was inactive in carcinoid and islet cell tumors, with 0 of 20 and 0 of 9 patients responding, respectively. Of the 41 total patients evaluable for response, only 2 (5%) achieved a partial response. Both of these responding patients had neuroendocrine tumors of unknown primary site. No complete responses were seen. Toxicities were those previously noted with carboplatin, with myelosuppression, particularly thrombocytopenia, being dose limiting.

CONCLUSIONS

Carboplatin is inactive in carcinoid tumors and did not show evidence of activity in islet cell tumors. Further investigations are needed to identify active agents in the treatment of neuroendocrine malignancies.

Octreotide as an antineoplastic agent in the treatment of functional and nonfunctional neuroendocrine tumors

BACKGROUND

Although patients with neuroendocrine tumors typically exhibit an indolent clinical course, the pace of disease accelerates and the prognosis deteriorates once objective progression of disease begins. Thirty-four patients with advanced neuroendocrine tumors were treated with octreotide as antineoplastic therapy. This treatment was begun only after documentation of clear objective progression of disease.

METHODS

A Phase II trial was performed at a tertiary comprehensive cancer center.

RESULTS

The median survival for this patient population from the start of octreotide therapy has not been reached, with a median follow-up of 29 months (range, 1-47 months). No major objective tumor regressions were seen. Seventeen patients (50%) experienced a computed tomography-documented stabilization of disease that was maintainable for a minimum of 2 months (median, 5 months; range, 0-27 months). Of the 34 patients, 20 patients received octreotide as their first antineoplastic therapy. The median survival for these 20 patients has not been reached, with a median follow-up also of 29 months (range, 12-41 months).

CONCLUSIONS

Octreotide may influence the natural history of neuroendocrine tumors. The survival in patients treated with octreotide, as measured from the time of progression of disease, compares favorably with that of historical controls. Proof of a survival advantage for patients treated with octreotide would require a multicenter, randomized trial.

Hepatic arterial chemoembolization for metastatic endocrine tumors

PURPOSE

In patients with hepatic metastases from endocrine tumors, the safety and effectiveness of chemoembolization with ethiodized oil was determined and compared with those of embolization with particulate matter alone.

PATIENTS AND METHODS

Twenty patients with hepatic islet cell or carcinoid tumor metastases were treated with selective hepatic artery injection of doxorubicin and iopamidol emulsified in ethiodized oil, followed by gelatin foam powder embolization.

RESULTS

In 16 patients with hormonally active tumors, hormone secretion decreased 90% (range, 69%-98%) in 10 days, with relief of symptoms in all patients. Average tumor size decrease was 84%; average hospitalization was 8 days. Seventeen patients are alive 6-27 months after embolization, and all are asymptomatic. Three patients died within 1 year after embolization of progressive disease outside the liver.

CONCLUSION

Chemoembolization with doxorubicin emulsified in ethiodized oil and iopamidol is effective in the treatment of hepatic metastases from endocrine tumors. This technique appears to result in less morbidity than particulate embolization alone.

An update of the medical treatment of malignant endocrine pancreatic tumors

In the present study, we have updated our results with chemotherapy, alpha-interferon, octreotide and combinations of treatment modalities in patients with malignant endocrine pancreatic tumor (EPT). In our patient material of 134 EPT, 92 subjects had malignant tumors as evidenced by the presence of metastases or growth into adjacent organs. Seventy-eight patients had liver metastases. Streptozotocin plus 5-fluorouracil produced objective responses in 17/31 (54%) patients with a median duration of response of 23 months. The use of 5-HT3-antagonists as antiemetics has dramatically improved the quality of life during treatment by reducing the frequency of nausea to only 12.5%. The objective response rate to alpha-interferon (alpha-IFN) treatment, given as first-line treatment in 29 patients and after chemotherapy in 28 patients, was 51% (29/57) with a median duration of response of 20 months. Octreotide, which is still used as third-line treatment in most patients, produced significant biochemical responses in 6/19 (31%) patients with a median duration of 16 months. Combinations of alpha-IFN plus chemotherapy and a alpha-IFN plus octreotide in a small number of patients might indicate additive or synergistic effects. The median survival from start of treatment in the 92 malignant cases was 56.5 months, and for those with liver metastases (n = 78) at start of treatment 50 months. In conclusion, there are at least three effective therapies for malignant EPT and by combining them simultaneously or consecutively, a median survival of more than four years can be obtained.

Clinical characteristics, treatment and survival in patients with pancreatic tumors causing hormonal syndromes

Eighty-five patients with endocrine pancreatic tumors associated with clinical syndromes of hormone excess were retrospectively analyzed regarding symptomatology, means of diagnosis, and results of surgical and medical treatment during follow-up of 3-18 years (median 8 years). The combination of angiography and computed tomography was most successful in pre-operative localization of both primary tumors and metastases. Surgery provided long term cure in 39 of 44 patients with benign islet cell lesions, the majority having insulinomas. Forty-one patients had malignant tumors, which at the time of diagnosis or operation were associated with liver and/or regional lymph gland metastases in 56% and 24%, respectively. Sixteen patients with metastatic disease and/or very large tumors were considered inoperable, 5 patients underwent palliative resection of their malignant tumors, while grossly radical tumor removal was accomplished in 20 patients. Long-term cure was achieved in 5 patients by excision of primary tumors and localized liver or lymph gland metastases. Half of the patients, particularly those with insulinoma, gastrinoma, or vipoma, showed response to streptozotocin, in combination with other cytostatics, for a median of 24 months or a response to interferon for a median of 10 months. The overall 5-year and 10-year survival among the patients with malignant islet cells tumors was 54% and 28%, respectively. Absence of liver metastases at time of operation/diagnosis, smaller size of the primary tumor, grossly radical tumor resection as well as response to medical therapy predicted the more favorable survival.

Recombinant interferon alpha-2b in patients with metastatic apudomas: effect on tumours and tumour markers

Malignant carcinoid tumours, islet cell tumours and medullary carcinomas of the thyroid are tumours with similar clinical features. In patients with unresectable or metastatic tumours leukocyte interferon (IFN) and recombinant human (rh) IFN have demonstrated efficacy. Twenty-four evaluable patients with progressive tumours were treated with 2.5 megaunits rh IFN alpha-2b, administered once daily subcutaneously, for a median duration of 7 months (range 0.5-37+). Two carcinoid patients demonstrated a response in tumour size, 80% showed stable disease (SD). Sixty percent of the carcinoid patients with elevated urinary 5-hydroxyindoleacetic (5-HIAA) levels reached a biochemical partial response of the urinary 5-HIAA levels (median duration 13.5 months). In the patients with an islet cell or medullary tumour and an elevated tumour marker, the marker did not further increase. Of the 12 carcinoid patients evaluable for a symptomatic response, ten (83%) experienced a relieve of symptoms. IFN alpha-2b dose reduction or discontinuation due to toxicity was necessary in three and ten patients, respectively. No neutralising IFN alpha-2b antibodies developed despite prolonged treatment. In conclusion, IFN alpha-2b had a beneficial effect in patients with progressive tumours, while long-term IFN alpha-2b treatment did not augment neutralising antibodies. In view of the IFN alpha-2b-related toxicity, administration of IFN alpha-2b on alternating days may be preferable.

Drug-induced diabetes

The only drugs which commonly cause diabetes during therapeutic use are the anti-hypertensive vasodilator diazoxide, and corticosteroids in high doses such as those used to palliate intracranial tumours. Thiazide diuretics have in the past been used in higher doses than necessary to treat hypertension, and the lower doses now used probably carry only a slight risk of inducing diabetes. The risk from beta-blockers is also quite small, but there is some evidence that thiazides combined with beta-blockers may be more likely to cause diabetes than either drug alone. The combination is probably best avoided in patients with a family history of non-insulin-dependent diabetes. The effect of the low-oestrogen combined oral contraceptive pill seems to be slight, and it presents a risk only to women who have had gestational diabetes. Bodybuilders who take enormous doses of anabolic-androgens can develop impaired glucose tolerance. Several drugs, including theophylline, aspirin, isoniazid and nalidixic acid can cause transient hyperglycaemia in overdosage, but only streptozotocin, alloxan and the rodenticide Vacor are likely to cause permanent diabetes.