Treatment of advanced neuroendocrine tumours using combination chemotherapy with lomustine and 5-fluorouracil

Indications for genetic study in gastro-entero-pancreatic and thoracic neuroendocrine tumors

Gastro-entero-pancreatic (GEP-NET) and thoracic neuroendocrine tumours (NETs) are one of the most heritable groups of neoplasms in the body, being multiple endocrine neoplasia syndrome type 1 (MEN1), the genetic syndrome most frequently associated with this type of tumours. Moreover, Von Hippel Lindau syndrome, tuberous sclerosis, type 4 multiple neoplasia syndrome, and type 1 neurofibromatosis are associated with an increased risk of developing GEP-NETs. Another important aspect in GEP-NETs and thoracic NETs is the knowledge of the molecular background since the molecular profile of these tumours may have implications in the prognosis and in the response to specific treatments. This review summarizes the main indications for performing a genetic study in patients with GEP-NETs and thoracic NETs, and the methods used to carry it out. Moreover, it offers a description of the main hereditary syndromes associated with these NETs and their molecular background, as well as the clinical implications of the molecular profile.

Medical Management of Gastroenteropancreatic Neuroendocrine Tumors

The increased incidence and prevalence of neuroendocrine tumors (NETs) over the past few decades has been accompanied by an improvement in overall survival. There are differences in the management of small bowel NETs versus pNETs. The management of all patients with NETs must be individualized based on patient characteristics as well tumor-related factors. This article reviews the role of somatostatin analogues, historical results with chemotherapy in gastroenteropancreatic NETs (GEPNETs), and more recent evidence for the use of cytotoxic chemotherapy in GEPNETs. The article also discusses molecular targeted therapies approved for use in GEPNETs and some ongoing clinical trials.

Current Treatments of Neuroendocrine Tumors Role of Biotherapy and Chemotherapy

Neuroendocrine tumors are rare neoplasms originating from cells belonging to a diffuse or confined neuroendocrine system and characterized by a significant histopatologic and biologic heterogeneity. Timely diagnosis is delayed because they are often clinically silent for their low differentiation grade and the absence of any symptom due to abnormal hormone release. For these reasons, many neuroendocrine tumor patients are not treated medically for metastatic or inoperable disease. Medical treatments include biotherapy, with interferon-α and somatostatin analogues, and chemotherapy. Somastostatin analogues are widely used in patients with symptoms and with carcinoids of low differentiation grade. Interferon-α is used alone or in combination with somatostatin analogues. Chemotherapy is active in patients with poorly differentiated neuroendocrine tumors. The therapeutic regimen commonly used is the combination of cisplatinum and etoposide. In conclusion, no standard treatment for NET has yet been identified, and the response criteria suggested by ITMO remain a reference point. The clinical aspect of the disease and biologic features suggest the identification of neuroendocrine tumors patients suitable for the appropriate therapies. On these bases, it is recommended that diagnosis and treatment of neuroendocrine tumors be carried out at specialized oncological centers involved in clinical trials.

Chemotherapy for advanced non-pancreatic well-differentiated neuroendocrine tumours of the gastrointestinal tract, a systematic review and meta-analysis: A lost cause?

BACKGROUND

Chemotherapy is well-established in the treatment of patients with well-differentiated neuroendocrine tumours (NETs) arising from the pancreas (pNETs); however, its role in patients with gastrointestinal non-pancreatic NETs (non-pNETs) is uncertain. This systematic review assesses the evidence for the role of chemotherapy in well-differentiated non-pNET patients.

METHODS

Eligible studies (identified using MEDLINE) were those reporting response and/or survival data for patients with well-differentiated non-pNETs receiving systemic chemotherapy. The primary end-point was overall-response (OR) rate; secondary end-points were progression-free survival (PFS), overall survival (OS), disease-stabilization (DS) and disease-control (DC) rates.

RESULTS

Of 6434 studies screened, 20 were eligible: one randomised phase III trial, 2 randomised phase II studies, 10 single-arm phase II trials and 7 retrospective analyses including a total of 264 patients (median of 11 patients per study, range 6-49); and employing multiple chemotherapy schedules. The mean "median PFS" and "median OS" were 16.9 months (95%-confidence interval (CI) 3.8-30.04) and 32.2 months (95%-CI 10.4-54.2), respectively. The non-weighted mean OR, DS and DC rates were 11.5% (95%-CI 5.8-17.2), 56.5% (95%-CI 38.1-74.9) and 70.7% (95%-CI 54.9-86.5), respectively. In studies including both pNETs and non-pNET patients, meta-analysis showed a lower OR-rate in the non-pNET patients when compared to pNETs [odds ratio (OR) 0.35 (95% CI 0.18-0.66)]; however significance was lost when high-risk bias studies were excluded in a sensitivity analysis [OR 0.45 (95% CI 0.19-1.07); p-value 0.07].

CONCLUSION

Studies were of evidence level-C with heterogeneous populations and treatments; and small patient numbers. Well-designed, prospective studies are needed to adequately evaluate the role of chemotherapy in this setting.

Peptide receptor radionuclide therapy of neuroendocrine tumors with (90)Y-DOTATOC: is treatment response predictable by pre-therapeutic uptake of (68)Ga-DOTATOC?

PURPOSE

PET with (68)Ga-DOTATOC allows for imaging and quantitative assessment of somatostatin receptor expression in neuroendocrine tumors (NET). The aim of this retrospective study was to analyze whether pre-therapeutic (68)Ga-DOTATOC PET/CT is able to predict response to Peptide Receptor Radionuclide Therapy (PRRT).

PATIENTS AND METHODS

Forty patients with advanced stage NET were treated with a fixed dose of (90)Y-DOTATOC (5550 or 3700MBq). Prior to PRRT, each patient received (68)Ga-DOTATOC PET/CT. Treatment results were evaluated after 3months by CT, tumor marker levels and clinical course and correlated with (68)Ga-DOTATOC uptake (SUVmax) and the assumed uptake of (90)Y-DOTATOC in tumor manifestations (MBq/g). ROC analysis and pairwise comparison of area under the curve (AUC) were performed with pre-treatment uptake of (68)Ga-DOTATOC, assumed uptake of (90)Y-DOTATOC and treatment activity alone and in relation to body weight as continuous variables, and response/no response as classification variable.

RESULTS

According to conventional criteria (tumor shrinkage, decrease of tumor markers, improved or stable clinical condition), 20 patients were classified as responders, 16 as non-responders and in four patients findings were equivocal. Using a SUV more than 17.9 as cut-off for favorable outcome, PET was able to predict treatment response of all responders and 15 out of 16 non-responders. All four patients with equivocal findings showed SUV less than or equal to 17.9 and soon experienced tumor progression. The assumed uptake of (90)Y-DOTATOC in tumor manifestations using a cut-off more than 1.26MBq/g as predictor of response was able to correctly classify 19 out of 20 responders, and 14 out of 16 non-responders. In all patients with equivocal findings, the assumed uptake of (90)Y-DOTATOC was below 1.26MBq/g.

CONCLUSION

Pre-therapeutic (68)Ga-DOTATOC tumor uptake as well as assumed uptake of (90)Y-DOTATOC are strongly associated with the results of subsequent PRRT. The defined cut-off values should be confirmed by prospective studies and may then provide the rationale for individual dosing and selecting patients with high likelihood of favorable treatment outcome.

Efficacy of adding high-dose In-111 octreotide therapy during Sandostatin treatment in patients with disseminated neuroendocrine tumors: clinical results of 14 patients

PURPOSE

This study aimed to assess the outcome of high-dose In-111 octreotide treatment and efficacy of long-acting Sandostatin LAR in patients with disseminated neuroendocrine tumors.

MATERIALS AND METHODS

A total of 14 patients (mean age 51.8 ± 13.2 years; 10 female, 4 male) receiving high-dose In-111 octreotide in our centre for the treatment of neuroendocrine tumors were included in the study. Monthly treatment with long-acting somatostatin analogue [Sandostatin long-acting release (Novartis Pharmaceuticals)] was continued in nine cases.

RESULTS

During a 3-year period, a total of 45 courses of high-dose In-111 octreotide treatment were delivered to 14 patients. In seven patients receiving an average of four treatment courses (6 carcinoid tumors, 1 thymoma, patients: 2, 4, 5, 11-14) stable disease was achieved (50%). In two patients with carcinoid tumors (patients 1 and 3) who received four treatment courses, partial response was observed (14%). Five patients (36%; 4 NET, 1 gastrinoma; patients 6-10) died due to progressive disease following on average two treatment courses. On average, deaths occurred 2 months after the last treatment dose. No complete responses were seen. Partial response was achieved in two of the nine patients receiving Sandostatin LAR, while four had stable disease. Both treatments were associated with acceptable tolerability.

CONCLUSIONS

High-dose In-111 octreotide can be safely administered in conjunction with somatostatin analogue in patients with disseminated NET and this treatment may help to stabilize the disease.

Laparoscopic radiofrequency thermal ablation of neuroendocrine hepatic metastases: long-term follow-up

BACKGROUND

Since our first report 13 years ago, laparoscopic radiofrequency ablation has been incorporated into the treatment algorithm of patients with neuroendocrine liver metastases. The aim of this study is to report long-term oncologic results.

METHODS

Eighty-nine patients with neuroendocrine hepatic metastases underwent 119 laparoscopic radiofrequency ablation sessions within 13 years. Data were obtained from a prospective, Institutional Review Board approved database. Univariate Kaplan Meier and multivariate Cox proportional hazards model were used for statistical analyses. Data are expressed as mean ± standard error of the mean.

RESULTS

Thirty-five women and 54 men with a mean age of 56 ± 1.4 years were included in this study. Tumor types included were carcinoid (n = 55), pancreatic islet cell (n = 23), and medullary thyroid cancer (n = 11). Mean tumor size was 3.6 ± 0.2 and the number of lesions was 6 ± 1. Perioperative morbidity was 6%, and 30-day mortality was 1%. Symptom relief was achieved in 97% of patients after radiofrequency ablation. Median follow-up was 30 ± 3 months. Twenty-two percent of patients developed local liver recurrence, 63% developed new liver lesions, and 59% developed extrahepatic disease in follow-up. Repeat radiofrequency ablation (27%) and chemoembolization (7%) were used to achieve additional local tumor control in follow up. Median disease-free survival was 1.3 years and the overall survival was 6 years after radiofrequency ablation. Liver tumor volume, symptoms, and extrahepatic disease were independent predictors of survival.

CONCLUSION

To our knowledge, this is the largest prospective experience with radiofrequency ablation of neuroendocrine liver metastases. Effective symptom palliation and long-term local tumor control are possible in these patients with minimal morbidity.

Selective internal radiation therapy for gastrointestinal neuroendocrine tumour liver metastases: a new and effective modality for treatment

Background. Nonresectable neuroendocrine tumour (NET) liver metastases respond poorly to most widely available and used therapies. Selective Internal Radiation Therapy (SIRT) is becoming recognized as a new modality for selectively treating non-resectable liver tumours. This paper presents an experience of 14 patients with non-resectable NET liver metastases treated with SIRT. Methods. Between September 1997 and October 2009 14 patients with extensive NET liver metastases were treated with 2.0 to 3.0 GBq of (90)Yttrium microspheres. Repeat SIRT was undertaken in three patients after 16, 27, and 48 months, respectively. Responses were assessed clinically, biochemically, and with serial CT scans. Survival was measured from initial SIRT. Results. Some response was seen in all 14 patients. Carcinoid syndrome improved or resolved in 10/10 instances. 24-hour urinary 5-HIAA or serum chromogranin A levels fell dramatically in 5/7 patients following SIRT. Serial CT scans revealed partial response or stable disease in all 14 patients. Repeat treatment in three patients experiencing progression was associated with a further response. Median survival after SIRT is 25 months with 6 patients being alive (and 3 patients still asymptomatic), at 19, 22, 23, 23, 58, and 60 months. Conclusions. SIRT is an effective and well-tolerated treatment for non-resectable NET liver metastases capable of both alleviating the carcinoid syndrome and achieving significant tumour regression. Repeat treatment is an option and liver resection after downstaging may also become possible.

Phase II study of pemetrexed in patients with advanced neuroendocrine tumors

PURPOSE

In some reports, 5-fluorouracil has been associated with modest activity in patients with neuroendocrine tumors. Pemetrexed is a multitargeted antifolate with activity in tumor types not significantly responsive to other antifolates. We evaluated the efficacy of pemetrexed in a phase II study of patients with advanced neuroendocrine tumors.

METHODS

Patients with metastatic neuroendocrine tumors (excluding small-cell carcinoma) were treated with pemetrexed administered intravenously at a dose of 500 mg/m(2) every 21 days. To reduce potential toxicity, patients also received folic acid, vitamin B12 supplementation, and peri-infusional treatment with dexamethasone. Patients were followed for response, toxicity, and survival.

RESULTS

The study was designed with a total accrual goal of 32 patients. Due to lack of radiographic responses in patients during the study period, accrual was terminated at 17. However, one patient achieved a delayed partial response following discontinuation of pemetrexed. Ten patients were evaluable for biochemical response; five (50%) experienced >50% decrease in plasma chromogranin A. Among the 17 patients, 5 (29%) discontinued therapy due to treatment-related toxicity. The median overall survival was 12.1 months.

CONCLUSION

Pemetrexed does not appear to have significant antitumor activity in patients with advanced neuroendocrine tumors. The limited antitumor activity and potential toxicity associated with pemetrexed mirrors experience with the majority of other cytotoxic agents in patients with neuroendocrine tumors. Investigation of novel, molecularly targeted agents may offer more promise in this disease.

Surgically treated primary malignant tumor of small bowel: A clinical analysis

AIM: To evaluate the clinical presentation, treatment and survival of patients with primary malignant tumor of small bowel (PMTSB).

METHODS: Clinicopathologic data about 141 surgically treated PMTSB patients (91 males and 50 females) at the median age of 53.5 years (range 23-79 years) were retrospectively analyzed.

RESULTS: The most common initial clinical features of the patients were intermittent abdominal discomfort or vague abdominal pain (67.4%), abdominal mass (31.2%), bowel obstruction (24.1%), hemotochezia (21.3%), jaundice (16.3%), fever (14.2%), coexistence of bowel perforation and peritonitis (5.7%), coexistence of gastrointestinal bleeding and shock (5.0%), and intraabdominal bleeding (1.4%). Ileum was the most common site of tumor (44.7%), followed by jejunum (30.5%) and duodenum (24.8%). PMTSB had a nonspecific clinical presentation. Segmental bowel resection (n = 81) was the most common surgical procedure, followed by right hemi-colectomy (n = 15), pancreaticoduodenectomy (n = 10), and others (n = 19). Twenty-seven adenocarcinoma patients and 13 malignant lymphoma patients received adjuvant chemotherapy with 5-fluorouracil and cyclophosphamide, adriamycin, vincristine and prednisone, respectively. Information about 120 patients was obtained during the follow-up. The median survival time of PMTSB patients was 20.3 mo. The 1-, 3- and 5-year survival rate was 75.0% (90/120), 40.0% (48/120) and 20.8% (25/120), respectively. Adenocarcinoma was found in 73.7% (42/57), 21.1% (12/57) and 15.8% (9/57) of the patients, respectively. Gastrointestinal stromal tumor was observed in 80.0% (20/25), 72.0% (18/25) and 36.0% (9/25) of the patients, respectively. Carcinoid was detected in 100.0% (15/15), 80.0% (12/15) and 46.7% (7/15) of the patients, respectively. Malignant lymphoma was demonstrated in 69.2% (9/13), 30.8% (4/13) and 0% (0/13) of the patients, respectively.

CONCLUSION: En bloc resection is the principal therapy for most PMTSB and chemotherapy is the important treatment modality for malignant lymphoma and other malignant tumors of small bowel which cannot be radically removed.

A case report of metastatic neuroendocrine carcinoma of the right adrenal gland successfully treated with chemotherapy and surgery

Poorly differentiated neuroendocrine carcinoma has a poor prognosis, especially when associated with distant metastasis. A 60-year-old man was admitted to a private hospital because of dyspnea at work in 2007. Computed tomography revealed lung infarction and a right adrenal tumor sized 12 cm in diameter that was tightly compressed against the inferior vena cava (IVC). Moreover, multiple lymph node metastases around the celiac axis and a solitary liver metastasis at the lateral segment were observed. Thus, we planned chemotherapy without surgery. We selected a combination therapy of irinotecan (CPT-11) and cisplatin (CDDP) (i.e., IP therapy): administration of CDDP [60 mg/m(2) body surface area (BSA)] on day 1 plus CPT-11 (80 mg/m(2)) BSA on days 1 and 8. Thereafter, this protocol was repeated at 3-week intervals. After 15 months of this chemotherapy strategy, the whole lesions showed a partial response by RECIST. The primary tumor had shrunk to 4.2 cm in diameter. In November 2008, we planned surgery to perform resection of the whole lesions. Histological diagnosis of the specimen was a poorly differentiated neuroendocrine carcinoma based on the immunostaining features, i.e., synaptophysin- and chromogranin positive. There were no viable tumor cells at the dissected lymph nodes or at the liver tumor. After surgery, CPT-11 administration was continued. The patient has remained well for 9 months without recurrence.

90Y-edotreotide for metastatic carcinoid refractory to octreotide

PURPOSE

Metastatic carcinoid is an incurable malignancy whose symptoms, such as diarrhea and flushing, can be debilitating and occasionally life-threatening. Although symptom relief is available with octreotide, the disease eventually becomes refractory to octreotide, leaving no proven treatment options. The goal of this study was to evaluate the clinical effect of using (90)Y-edotreotide to treat symptomatic patients with carcinoid tumors.

PATIENTS AND METHODS

Patients enrolled had metastatic carcinoid, at least one sign/symptom refractory to octreotide, and at least one measurable lesion. Study treatment consisted of three cycles of 4.4 GBq (120 mCi) (90)Y-edotreotide each, once every 6 weeks.

RESULTS

Ninety patients were enrolled in the study. Using Southwest Oncology Group tumor response criteria, 67 (74.%) of 90 patients (95% CI, 65.4% to 83.4%) were objectively stable or responded. A statistically significant linear trend toward improvement was demonstrated across all 12 symptoms assessed. Median progression-free survival was significantly greater (P = .03) for the 38 patients who had durable diarrhea improvement than the 18 patients who did not (18.2 v 7.9 months, respectively). Adverse events (AEs) were reported in 96.7% (87 of 90) of patients. These AEs consisted primarily of reversible GI events (76 of 90), which could be caused in part by concomitant administration of amino acid solution given to reduce radiation exposure to the kidneys. There was one case each of grade 3 oliguria and grade 4 renal failure, each lasting 6 days.

CONCLUSION

(90)Y-edotreotide treatment improved symptoms associated with malignant carcinoid among subjects with no treatment alternatives. Treatment was well-tolerated and had an acceptable expected AE profile.

Endocrine pancreatic tumors: diagnosis and treatment

Endocrine pancreatic tumors (EPTs) are uncommon, having an incidence of one per 100,000 people. They may appear as sporadic tumors or be associated with hereditary syndromes. EPTs are categorized as functioning or nonfunctioning tumors, based on the presence or absence of clinical syndromes. Among the former, insulinomas and gastrinomas are the most common. For the histopathological investigation of EPTs, chromogranin A and synaptophysin immunostainings are recommended. Measurement of circulating chromogranin A is also the cornerstone for the biochemical diagnosis of these tumors. Furthermore, specific hormones produced and released by the neoplastic cells can be identified by immunostaining and used for biochemical evaluation. To locate EPTs, both noninvasive (ultrasonography, computerized tomography, MRI and radionuclear imaging) and invasive techniques (arterial stimulation with venous sampling) can be used. Debulking procedures (surgery, radiofrequency ablation, embolization/chemoembolization and liver transplantation) and/or medical treatment (chemotherapy, biotherapy and peptide receptor radionuclide therapy) are the options available for the treatment of EPTs. Understanding the molecular events underlying the pathobiology of EPTs will aid the development of more accurate diagnostic/prognostic markers and give guidance for improved therapeutic modalities.

Treatment of gastroenteropancreatic neuroendocrine tumors

Neuroendocrine tumors are rare; thus, individual experience with the diagnosis and treatment of these tumors is mostly low, except in specialized centers. For histological diagnosis, standards have been described recently. Pathological classification and clinical staging influence diagnostic and therapeutic decisions. This chapter aims at demonstrating the importance of pathological and clinical classification of neuroendocrine tumors on therapeutic decisions, indicating the appropriate therapy for different stages of the disease. Surgical therapy will be discussed shortly, including palliative surgical strategies. However, the focus of the manuscript is medical therapy. Biotherapy, its effects, and remaining uncertainties are presented as well as different chemotherapeutic schemes. Finally, new options of palliative medical therapies like kinase inhibitors and anti-angiogenetic drugs will be discussed.

Endocrine tumors of the pancreas

Neuroendocrine tumors of the pancreas are rare neoplasms of the heterogeneous group of neuroendocrine gastroenteropancreatic tumors that originate from totipotential stem cells or preexisting endocrine cells within the pancreas. Most neuroendocrine tumors of the pancreas are benign or show an indolent course of disease.A subset of them shows a very aggressive behavior, becomes highly malignant, and metastasizes early with life-limiting consequences. An effective disease-management includes the diagnostic approach with hormonal testing and localization and surgical treatment with histologic classification in combination with biotherapy, chemotherapy, or therapy with radionucleotides, de-pending on the individual behavior of the tumor. The primary goal is the improvement of symptoms leading to an acceptable quality of life in the individual patient.

Therapeutic options for gastrointestinal carcinoids

Although wide surgical resection is the optimal curative therapy for carcinoid tumors, in most patients the presence of metastatic disease at diagnosis usually renders excision a palliative procedure. This nevertheless decreases tumor burden, facilitates symptom control, and prevents complications caused by bleeding, perforation, or bowel obstruction resulting from fibrosis. In the stomach (types I and II) and rectum endoscopic excision may be adequate provided the lesion(s) are local. Long-term therapy is focused on symptom alleviation and improvement of quality of life using somatostatin analogues, particularly in a subcutaneous depot formulation. In some instances interferons may have a role but their usage often is associated with substantial adverse events. Conventional chemotherapy and external radiotherapy either alone or in a variety of permutations are of minimal efficacy and should be balanced against the decrease in quality of life often engendered by such agents. Hepatic metastases may be amenable to surgery, radiofrequency ablation, or embolization either alone or in combination with chemotherapeutic agents or isotopically loaded microspheres. Rarely hepatic transplantation may be of benefit although controversy exists as to its actual use. Peptide-receptor-targeted radiotherapy for advanced disease using radiolabeled octapeptide analogs (111In/90Yt/177Lu-octreotide) appear promising but data are limited and its status remains investigational. A variety of antiangiogenesis and growth factor-targeted agents have been evaluated, but as yet have shown little promise. The keystone of current therapy remains the long-acting somatostatin analogues that alleviate symptomatology and substantially improve quality of life with minimal adverse effects.

Insulin-producing cells derived from human pancreatic non-endocrine cell cultures reverse streptozotocin-induced hyperglycaemia in mice

AIMS/HYPOTHESIS

The aim of the study was to investigate the potential of human pancreatic non-endocrine cells to transdifferentiate into endocrine cells that would be capable of secreting insulin in response to glucose and ameliorating insulin-deficient diabetes after transplantation.

MATERIALS AND METHODS

Cell fractions enriched with exocrine cells after human islet isolation were treated with streptozotocin to remove residual beta cells, grown in monolayer culture to allow de-differentiation, transferred to cluster culture for redifferentiation in the presence of activin A, betacellulin, nicotinamide and glucose, supplemented with 10% FCS, and administered to streptozotocin-induced diabetic SCID mice. A subset of cells was transfected with the IPF1 gene (also known as PDX1) before transdifferentiation.

RESULTS

No insulin was detectable in cell preparations after 5 days of treatment with streptozotocin. In monolayer culture, 90% of the streptozotocin-treated pancreatic cells co-expressed cytokeratin-19 and vimentin at 2 weeks and 60% expressed nestin at 4 weeks. Cell cultures with a high proportion of nestin-expressing cells had greater plasticity for transdifferentiation into cells with phenotypic and functional markers of beta cells, this property being significantly enhanced by transfection with IPF1 gene and leading to 15+/-6.7% insulin-positive cells after transplantation vs. 0.01% of cells transplanted after streptozotocin treatment alone. These cells improved glucose control in all of 42 diabetic mice after transplantation, restoring normoglycaemia in 40%.

CONCLUSIONS/INTERPRETATION

Human pancreatic cells are a potential source of new glucose-responsive insulin-producing cells that may be developed further for clinical use.

Fluorouracil, doxorubicin, and streptozocin in the treatment of patients with locally advanced and metastatic pancreatic endocrine carcinomas

PURPOSE

The role of systemic chemotherapy in the management of pancreatic endocrine carcinoma (islet cell carcinoma; PEC) is an area of considerable controversy. Response rates ranging from 6% to 69% have been reported for streptozocin-based chemotherapy. We retrospectively studied 84 patients with locally advanced or metastatic PEC who had been treated with fluorouracil, doxorubicin, and streptozocin (FAS) to determine the objective response rate, duration of progression-free survival (PFS), and duration of overall survival (OS).

PATIENTS AND METHODS

Eligible patients had histologic or cytologic confirmation of their tumor and measurable disease on computed tomography or magnetic resonance imaging scans. Response to treatment was evaluated in this study using the new international criteria proposed by the Response Evaluation Criteria in Solid Tumors Committee.

RESULTS

Sixty-one of the patients were male and 23 were female, with a median age of 54 years (range, 24 to 78 years). The response rate (RR) to FAS was 39%, with a median response duration of 9.3 months. The 2-year PFS rate was 41%, and the 2-year OS rate was 74%. The extent of liver metastatic disease correlated with a worse PFS (P = .01 by log-rank test) and a worse OS (P < .0001 by log-rank test). Analyses showed that metastatic replacement of more than 75% of the liver and prior chemotherapy were independently associated with inferior PFS.

CONCLUSION

Patients with locally advanced or metastatic PEC who are treated with FAS may have a reasonable RR, and responders may experience longer PFS and OS. The volume of metastases in the liver is the most important predictor of outcome.

GOT1 xenografted to nude mice: a unique model for in vivo studies on SSTR-mediated radiation therapy of carcinoid tumors

Malignant carcinoid tumors express high numbers of somatostatin receptors. Radiation therapy using labeled somatostatin analogs is a novel treatment modality for these tumors. We have analyzed the biokinetics and therapeutic effect of radiolabeled somatostatin analog on a human midgut carcinoid grafted to nude mice. A transplantable human midgut carcinoid (GOT1) was grafted to the back of nude mice. Tumor-bearing mice were injected with (111)In-DTPA-D-Phe(1)-octreotide, followed by measurement of (111)In activity concentration ratios in tumor tissues. Tumor-bearing mice were also injected with (177)Lu-DOTA-Tyr(3)-octreotate and followed for 7 days. The concentration of (111)In-DTPA-D-Phe(1)-octreotide in tumor tissues was very high 4 hours postinjection with 0.4-13% of injected activity per gram. Injection of 30-120 MBq (177)Lu-DOTA-Tyr(3)-octreotate reduced tumor volume to 7-14% of the original tumor volume 7 days postinjection. Microscopic analysis of treated tumors revealed widespread areas of tumor cell necrosis and fibrosis. It was found that grafted GOT1 cells to nude mice represent an authentic model for studying human midgut carcinoids. Radiolabeled somatostatin analogs have a high selectivity for tumor tissue and can induce tumor cell necrosis. Radiotherapy of carcinoid tumors with (177)Lu-DOTA-Tyr(3)-octreotate appears to be a promising treatment modality for either palliative treatment or completion therapy after attempted surgical cure.

The diagnosis and medical management of advanced neuroendocrine tumors

Neuroendocrine tumors (NETs) constitute a heterogeneous group of neoplasms that originate from endocrine glands such as the pituitary, the parathyroids, and the (neuroendocrine) adrenal, as well as endocrine islets within glandular tissue (thyroid or pancreatic) and cells dispersed between exocrine cells, such as endocrine cells of the digestive (gastroenteropancreatic) and respiratory tracts. Conventionally, NETs may present with a wide variety of functional or nonfunctional endocrine syndromes and may be familial and have other associated tumors. Assessment of specific or general tumor markers offers high sensitivity in establishing the diagnosis and can also have prognostic significance. Imaging modalities include endoscopic ultrasonography, computed tomography and magnetic resonance imaging, and particularly, scintigraphy with somatostatin analogs and metaiodobenzylguanidine. Successful treatment of disseminated NETs requires a multimodal approach; radical tumor surgery may be curative but is rarely possible. Well-differentiated and slow-growing gastroenteropancreatic tumors should be treated with somatostatin analogs or alpha-interferon, with chemotherapy being reserved for poorly differentiated and progressive tumors. Therapy with radionuclides may be used for tumors exhibiting uptake to a diagnostic scan, either after surgery to eradicate microscopic residual disease or later if conventional treatment or biotherapy fails. Maintenance of the quality of life should be a priority, particularly because patients with disseminated disease may experience prolonged survival.

Prediction of clinical outcome in treated neuroendocrine tumours of carcinoid type using functional volumes on 111In-pentetreotide SPECT imaging

The quantification of the tumour volume is essential for the assessment of therapy-induced changes. Traditional methods of assessing the response of neuroendocrine tumours using radiological methods yield poor results, particularly within the liver. The aim of this study was to establish whether it would be possible to identify a method using functional volumes to predict the response of tumours to various therapies. Twenty-two patients with neuroendocrine tumours of carcinoid type in the liver were treated with chemotherapy, chemo-embolization or 90Y-radiolabelled somatostatin analogues. All patients underwent 111In-pentetreotide single-photon emission computed tomography (SPECT) and computed tomography (CT) scan pre- and post-treatment. The tumour functional volume, a measure of metabolically active tumour tissue, was calculated from the SPECT images using a 10-point display; regions of interest were drawn around 50% of the maximum tumour activity, slice by slice, and then multiplied by the slice thickness (9.3 mm). Any difference in functional volume was compared with the CT response, using the Response Evaluation Criteria in Solid Tumours (RECIST), and clinical outcome. At 6 months after treatment, 14 patients showed a good clinical response, as measured by a reduction in pain, flushing or abdominal symptoms; the functional volume of the tumours in these patients decreased by a mean of 25% (range, 1-52%). Of the eight patients who showed no symptomatic relief, or in whom symptoms worsened, the functional volume increased by a mean of 74%. Using a change in functional volume of more than 25% as significant, SPECT predicted 13 of the 22 (59%) clinical outcomes correctly; if a 10% change was used, 18 of the 22 (81.1%) clinical outcomes were correctly predicted. However, CT, using RECIST, only predicted eight of the 22 (36%) clinical outcomes correctly. The assessment of the total functional volume by SPECT quantification is more useful than CT in monitoring tumour response after treatment, and the changes in functional volumes after therapy correlate well with the clinical response.

Basis for treatment of functioning neuroendocrine tumours

A general characteristic of GEP endocrine tumours is that vast majority produce and secrete a multitude of peptide hormones and amines. The rarity of these types of tumours, their possible episodic expression and the variable clinical symptoms, are the reasons why patients are often diagnosed late in the advanced stages of the disease. For these reasons, the patients with advanced metastatic disease should be treated aggressively with medical and surgical therapies aimed at reducing both symptoms and complications through strategies that reduce tumour bulk and block hormonal effects. The medical treatment of functioning endocrine tumours of the gastrointestinal tract must be based on the growth properties of the tumour and includes chemotherapy, somatostatin analogs, alpha-interferon alone and associated with somatostatin analogs, chemoembolization and radiolabelled somatostatin analogs. Even if chemotherapy has been basis of therapy for these types of tumours for a long time, it is currently reserved for progressive disease and anaplastic tumours. Biotherapy, with interferon and somatostatin analogs has been demonstrated to have a significant antitumor effect and causes an improvement of symptoms in patients with functioning neuroendocrine tumours. Furthermore, these drugs produce a notable improvement in the quality of life. Radioactive targeting therapy is the most promising new treatment modality for patients who have SST receptor positive tumours.

Treatment of neuroendocrine tumours with infusional 5-fluorouracil, folinic acid and streptozocin

A standardised, effective systemic therapy for metastatic neuroendocrine tumours (NETs) has not been established to date. We reviewed the management of 15 patients with inoperable, metastatic NET treated systematically with a combination chemotherapy regimen of infusional 5-fluorouracil, folinic acid and streptozocin. Overall objective response rate was 53% and tolerability was excellent.

Randomized clinical trial of the effect of interferon alpha on survival in patients with disseminated midgut carcinoid tumours

BACKGROUND

Midgut carcinoid tumours often present with widespread disease making curative surgery impossible. Medical treatment therefore plays a major role in the treatment of these patients.

METHODS

In this prospective randomized study, the effect of interferon (IFN) alpha on survival and risk of tumour progression was evaluated in 68 patients with midgut carcinoid tumours metastatic to the liver. All patients had undergone primary surgical treatment and hepatic arterial embolization of liver metastases before randomization. Patients were randomized to treatment with either octreotide alone (n = 35) or octreotide in combination with IFN-alpha (n = 33).

RESULTS

Forty-one of the 68 patients died during a follow-up period of 33-120 months, equivalent to a 5-year survival rate of 46.5 per cent. There was no significant difference in survival between patients treated with octreotide alone (5-year survival rate 36.6 per cent) and those given octreotide in combination with IFN-alpha (56.8 per cent). However, patients treated with IFN-alpha had a significantly reduced risk of tumour progression during follow-up (P = 0.008).

CONCLUSION

Addition of IFN-alpha to octreotide may retard tumour growth in patients with midgut carcinoid tumours.