Prospective, randomized, multicenter trial on the antiproliferative effect of lanreotide, interferon alfa, and their combination for therapy of metastatic neuroendocrine gastroenteropancreatic tumors--the International Lanreotide and Interferon Alfa Study Group. (57/805)

PURPOSE: Somatostatin analogs and interferon alfa control hormone-active/functional neuroendocrine gastroenteropancreatic tumors. In addition to hormonal control, variable degrees of antiproliferative effects for both agents have been reported. Until now, however, no prospective, randomized studies in therapy-naive patients have compared somatostatin analogs or interferon alfa alone with a combination of the two. METHODS: Eighty therapy-naive patients with histologically verified neuroendocrine tumor disease (primary localization: foregut, n = 36; midgut, n = 30; hindgut, n = 3; unknown, n = 11; functional, n = 29; nonfunctional, n = 51) were randomly treated either with lanreotide (1 mg three times a day administered subcutaneously [SC]) or interferon alfa (5 x 106 U three times a week SC) or both. All patients had disease progression in the 3 months before study entry, verified with imaging procedures. RESULTS: Twenty-five patients were treated with lanreotide, 27 patients were treated with interferon alfa, and 28 patients were treated with the combination. Partial tumor remission was seen in four patients (one patient who received lanreotide, one patient who received interferon alfa, and two patients who received the combination). During the 12 months of therapy, stable disease was observed in 19 patients (seven patients who received lanreotide, seven patients who received interferon alfa, and five patients who received the combination), whereas tumor progression occurred in 14 of 25 patients (lanreotide), 15 of 27 patients (interferon alfa), and 14 of 28 patients (combination). Side effects leading to an interruption of therapy were more frequent in the combination group than in the monotherapy arms. CONCLUSION: This prospective, randomized, multicenter study shows for the first time that somatostatin analogs, interferon alfa, or the combination of the two had comparable antiproliferative effects in the treatment of metastatic neuroendocrine gastroenteropancreatic tumors. Response rates were lower compared with those published in previous, nonrandomized studies. The antiproliferative effect of the tested substances was similar for functional and nonfunctional neuroendocrine tumors.  (+info)

Treatment of neuroendocrine tumours with infusional 5-fluorouracil, folinic acid and streptozocin. (58/805)

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.  (+info)

Autocrine growth inhibition by transforming growth factor beta-1 (TGFbeta-1) in human neuroendocrine tumour cells. (59/805)

BACKGROUND AND AIM: The role of transforming growth factor beta-1 (TGFbeta-1) in neuroendocrine tumour biology is currently unknown. We therefore examined the expression and biological significance of TGFbeta signalling components in neuroendocrine tumours (NETs) of the gastroenteropancreatic (GEP) tract. METHODS: Expression of TGFbeta-1 and its receptors, Smads and Smad regulated proteins, was examined in surgically resected NET specimens and human NET cell lines by immunohistochemistry, reverse transcriptase-polymerase chain reaction, immunoblotting, and ELISA. Activation of TGFbeta-1 dependent promoters was tested by transactivation assays. Growth regulation was evaluated by cell numbers, soft agar assays, and cell cycle analysis using flow cytometry. The role of endogenous TGFbeta was assessed by a TGFbeta neutralising antibody and stable transfection of a dominant negative TGFbetaR II receptor construct. RESULTS: Coexpression of TGFbeta-1 and its receptors TGFbetaR I and TGFbetaR II was detected in 67% of human NETs and in all three NET cell lines examined. NET cell lines expressed the TGFbeta signal transducers Smad 2, 3, and 4. In two of the three cell lines, TGFbeta-1 treatment resulted in transactivation of a TGFbeta responsive reporter construct as well as inhibition of c-myc and induction of p21((WAF1)) expression. TGFbeta-1 inhibited anchorage dependent and independent growth in a time and dose dependent manner in TGFbeta-1 responsive cell lines. TGFbeta-1 mediated growth inhibition was due to G1 arrest without evidence of induction of apoptosis. Functional inactivation of endogenous TGFbeta revealed the existence of an autocrine antiproliferative loop in NET cells. CONCLUSIONS: Neuroendocrine tumour cells of the gastroenteropancreatic tract are subject to paracrine and autocrine growth inhibition by TGFbeta-1, which may account in part for the low proliferative index of this tumour entity.  (+info)

CD56 expression of neuroendocrine neoplasms on immunophenotyping by flow cytometry: a novel diagnostic approach to fine-needle aspiration biopsy. (60/805)

BACKGROUND: CD56 antigen or NCAM (neural cell adhesion molecule) has an established role in the diagnosis of non-Hodgkin lymphoma (NHL)-natural killer cell type and other hematologic malignancies. Therefore, it is included routinely in the panel of antibodies for flow cytometric (FC) analysis of suspected lymphomatous tissue specimens obtained from fine-needle aspiration biopsy (FNAB). The authors evaluated the role of CD56 expression on FC of neuroendocrine (NE) tumors. An initial diagnosis of NHL was suspected based on an on-site FNAB evaluation. METHODS: Ten FNABs were identified from the cytopathology files at The Johns Hopkins Hospital, Baltimore, MD (2000-2001). Flow cytometric analysis was negative for NHL but revealed a CD56-positive nonlymphoid cell population. An FNAB evaluation was performed on air-dried Diff-Quik-stained smears and FC analysis used a fixed panel of 12 antibodies (B-cell markers, T-cell markers, CD33, CD56, and CD71). Immunoperoxidase staining (IPOX) was performed on the cell block sections from four of the tissue specimens using epithelial and NE markers, CD56, desmin, and O13 antibodies. Sites of FNAB included the lung (five cases), liver (one case), lymph node (three cases), and peritoneum (one case). Only one patient had a history of cancer at the time of FNAB. RESULTS: All cytologic diagnoses were confirmed by histopathologic follow-up on resection or biopsy or both. Diagnoses included small cell carcinoma (eight cases), Merkel cell carcinoma (one case), and primitive neuroectodermal tumor/Ewing sarcoma (one case). All tissue specimens that underwent IPOX stained strongly with NE markers, with one tissue section staining only with O13. CONCLUSIONS: CD56 expression by FC in the presence of negative immunostaining with lymphoid markers represented a unique yet highly specific method for the diagnosis of NE tumors by FNAB. This procedure eliminated the need for further IPOX studies on the already limited cytologic sample and provided a timely and accurate diagnosis.  (+info)

123I-Metaiodobenzylguanidine uptake in the nape of the neck of children: likely visualization of brown adipose tissue. (61/805)

The distribution of radioiodinated metaiodobenzylguanidine (MIBG) has been studied primarily in patients with neuroendocrine tumors-in pediatrics, particularly with neuroblastomas. Sometimes, symmetric accumulation in which no tumor is identified is seen in the nape-of-the-neck region. We estimated visually whether accumulation was found in the nape of the neck and studied the characteristics of the accumulation. METHODS: Retrospectively, we investigated 266 (123)I-MIBG scintigraphic studies performed on pediatric patients who had been treated for neuroendocrine tumors or who were suspected of having such tumors. RESULTS: Accumulation in the nape of the neck was seen in 32 of 266 studies (12%); in none of these cases was the accumulation identified as a tumor by other imaging modalities or follow-up studies. In the same individuals, the accumulation varied and it was observed more often during winter. CONCLUSION: Symmetric (123)I-MIBG accumulations in the nape-of-the-neck region observed in children are thought to be related to the uptake in brown adipose tissue.  (+info)

Interferons in the management of neuroendocrine tumors and their possible mechanism of action. (62/805)

Alpha interferons at doses of 3-9 MU subcutaneously, three to seven times/week, have been administered to 32 patients with malignant endocrine pancreatic tumors. The objective biochemical response rate was 63 percent with a median duration of 20.5 months. Significant reduction of tumor size was only noticed in 20 percent of the patients. Alpha interferon administered to 111 patients with malignant carcinoid tumors showed objective biochemical responses in 42 percent of the patients with a median duration of 32 months. Another 39 percent of the patients showed stabilization of disease without any further tumor growth. Subjective improvement was noticed in 70 percent of the patients. When survival data are analyzed in patients with malignant carcinoid tumors, the median survival from start of treatment was 80+ months in the group of patients treated with alpha interferon, which should be compared with only eight months in a historical group treated with chemotherapy (streptozotocin plus 5-fluorouracil). The adverse reactions to alpha-interferon treatment are dose-dependent and include, mainly, flu-like symptoms, fatigue, and low-grade weight loss. Autoimmune reactions are noted in about 20 percent of the patients. Patients treated with recombinant alpha interferons might develop neutralizing interferon antibodies (6-27 percent), which abrogate the anti-tumor response. The anti-tumor effect in neuroendocrine tumors includes anti-proliferation, apoptosis, differentiations, and cytotoxic/cytostatic effects. Furthermore, immunomodulation is obtained by increased expression of class I antigens on tumor cells. Four patients also developed antibodies directed against carcinoid tumor cells. Alpha interferons induce several nuclear enzymes such as 2'-5'-A synthetase, p-68 kinase, and Mx-A proteins, which are involved in a downregulation of expression of growth factors, oncogenes, and peptide hormones, leading to anti-proliferation and/or apoptosis. The response to alpha-interferon treatment might be predicted by analysis of the induction of 2'-5'-A synthetase in samples from neuroendocrine tumors. Stimulatory tests of hormone secretion, such as meal stimulation of pancreatic polypeptide secretion or secretin test, clearly demonstrate a normalization during alpha-interferon treatment, which might depend on reduced peptide production and/or secretion but also on eradication of malignant cell clones. In summary, alpha interferons have demonstrated significant anti-tumor effects in patients with malignant neuroendocrine gut and pancreatic tumors. The adverse reactions are dose-dependent and manageable. The anti-tumor effects of alpha interferons are pleiotropic and include several direct effects on tumor cells but also immunomodulation.  (+info)

The presence of somatostatin receptors in malignant neuroendocrine tumor tissue predicts responsiveness to octreotide. (63/805)

In 77 percent of patients suffering from a malignant carcinoid syndrome, administration of the somatostatin analog, octreotide (SMS 201-995, Sandostatin) induced clinical improvement coupled with a decrease in 24-hour urinary 5-hydroxyindole acetic acid (5-HIAA). This finding prompted an evaluation to determine the correlation between the presence of somatostatin receptors in tumor tissue and the response to octreotide in patients with advanced, metastatic, neuroendocrine tumors. In tissues of 31 tumors (20 carcinoid, eight islet-cell carcinoma, three medullary thyroid carcinomas), the presence of somatostatin receptors was analyzed by binding of the somatostatin analog 125I-Tyr3-SMS 201-995 and autoradiography. Receptors were detected in 16 of 20 samples of carcinoid tissues; all but one patient with receptor-positive tumors improved clinically after treatment with octreotide, and the urine 5-HIAA level was reduced a median of 63 percent (range, 39-94 percent) compared to values before treatment. Of the receptor-negative carcinoid patients, only one showed clinical improvement, which was minimal, and there was a negligible reduction in 5-HIAA after octreotide therapy. All eight patients with metastatic islet-cell carcinomas were positive for somatostatin receptors. Symptomatic improvement and a > 50 percent decrease in the level of at least one of the pathologically elevated marker hormones was seen in all eight. None of the three patients with medullary carcinoma of the thyroid had a decrease in calcitonin, and all three were initially somatostatin receptor-negative. We conclude that the presence of somatostatin receptors in malignant neuroendocrine tumor tissue appears to correlate with the response to octreotide therapy. Analysis of somatostatin receptors in malignant neuroendocrine carcinoma tissue should be included in future prospective clinical trials of this synthetic peptide.  (+info)

Uptake of meta-iodobenzylguanidine in neuroendocrine tumours is mediated by vesicular monoamine transporters. (64/805)

The radio-iodinated noradrenaline analogue meta-iodobenzylguanidine (MIBG) can be used for scintigraphy and radiation therapy of neuroendocrine (NE). The aim of the present study was to study the importance of vesicular monoamine transporters (VMATs) for the uptake of (123)I-MIBG in NE tumours. In nude mice, bearing the human transplantable midgut carcinoid GOT1, all organs and xenografted tumours accumulated (123)I after i.v. injection of (123)I-MIBG. A high concentration of (123)I was maintained in GOT1 tumours and adrenals, which expressed VMATs, but rapidly decreased in all other tissues. In the VMAT-expressing NE tumour cell lines GOT1 and BON and in VMAT-expressing primary NE tumour cell cultures (carcinoids, n=4 and pheochromocytomas, n=4), reserpine significantly reduced the uptake of (123)I-MIBG. The membrane pump inhibitor clomipramine had no effect on the uptake of (123)I-MIBG in GOT1 and BON cells, but inhibited the uptake in one out of four primary carcinoid cell cultures and three out of four primary pheochromocytoma cell cultures. In conclusion, VMATs and secretory granules are of importance for the uptake and retention of (123)I-MIBG in NE tumours. Information about the type and degree of expression of VMATs in NE tumours may be helpful in future to select patients suitable for radiation therapy with radio-iodinated MIBG.  (+info)