Management of Neuroendocrine Tumors: A Meeting of Experts from Latin America

A panel of experts from Latin America convened in Brazil, in May of 2007, for consensus recommendations regarding the management of neuroendocrine tumors ( NETs) of the gastrointestinal tract and pancreas. The recently introduced World Health Organization classification of NETs represents a step forward, but the former classification of carcinoids into foregut, midgut and hindgut is still likely to be useful in the near future. Macroscopic description of the tumor should be followed by light microscopic examination and immunohistochemical staining, whereas other techniques might not be widely available in Latin America. Surgery remains the mainstay of treatment for patients with potentially curable tumors, and adequate selection is paramount in order to optimize treatment results. Regarding systemic therapy, patients with well-differentiated tumors or islet-cell carcinomas may be categorized as having indolent disease, while patients with poorly differentiated, anaplastic, and small-cell carcinomas, or with atypical carcinoids, may be approached initially as having aggressive disease. Somatostatin analogues play a cytostatic role in indolent tumors, and chemotherapy may play a role against other, more aggressive NETs. Obviously, there is an urgent need for novel therapies that are effective against NETs. Copyright (C) 2008 S. Karger AG, Basel

Neuroendocrine Tumors (NETs): A population-based study of incidence and survival in Girona province, 1994-2004

Els tumors neuroendocrins (TNEs) són un grup de neoplàsies poc freqüents i heterogènies i amb un ampli espectre d’agressivitat. Hi ha molt poca informació epidemiològica a nivell mundial, l’objectiu d’aquest estudi ha estat el de reportar-ne les dades a la província de Girona. Hem inclòs tots els codis de la ICD-O3 que codifiquen un TNE, període 1994-2002. Hem identificat 698 tumors. Es reporten les dades tant de la casuística com les taxes d’incidència i supervivència de cada TNE per separat. Els resultats són consistents amb les publicacions europees. El fet d’haver reportat la incidència i la supervivència dels TNEs a Girona contribueix a un millor coneixement d’aquestes neoplàsies.

Liver Transplantation for Neuroendocrine Tumors in Europe-Results and Trends in Patient Selection: A 213-Case European Liver Transplant Registry Study.

OBJECTIVE:: The purpose of this study was to assess outcomes and indications in a large cohort of patients who underwent liver transplantation (LT) for liver metastases (LM) from neuroendocrine tumors (NET) over a 27-year period. BACKGROUND:: LT for NET remains controversial due to the absence of clear selection criteria and the scarcity and heterogeneity of reported cases. METHODS:: This retrospective multicentric study included 213 patients who underwent LT for NET performed in 35 centers in 11 European countries between 1982 and 2009. One hundred seven patients underwent transplantation before 2000 and 106 after 2000. Mean age at the time of LT was 46 years. Half of the patients presented hormone secretion and 55% had hepatomegaly. Before LT, 83% of patients had undergone surgical treatment of the primary tumor and/or LM and 76% had received chemotherapy. The median interval between diagnosis of LM and LT was 25 months (range, 1-149 months). In addition to LT, 24 patients underwent major resection procedures and 30 patients underwent minor resection procedures. RESULTS:: Three-month postoperative mortality was 10%. At 5 years after LT, overall survival (OS) was 52% and disease-free survival was 30%. At 5 years from diagnosis of LM, OS was 73%. Multivariate analysis identified 3 predictors of poor outcome, that is, major resection in addition to LT, poor tumor differentiation, and hepatomegaly. Since 2000, 5-year OS has increased to 59% in relation with fewer patients presenting poor prognostic factors. Multivariate analysis of the 106 cases treated since 2000 identified the following predictors of poor outcome: hepatomegaly, age more than 45 years, and any amount of resection concurrent with LT. CONCLUSIONS:: LT is an effective treatment of unresectable LM from NET. Patient selection based on the aforementioned predictors can achieve a 5-year OS between 60% and 80%. However, use of overly restrictive criteria may deny LT to some patients who could benefit. Optimal timing for LT in patients with stable versus progressive disease remains unclear.

Practical management of sunitinib toxicities in the treatment of pancreatic neuroendocrine tumors.

Pancreatic neuroendocrine tumors (pNETs) are infrequent malignancies which manifest in both functional (hormone-secreting) and more commonly non-functional (non-secreting) forms. The oral multitargeted tyrosine kinase inhibitor sunitinib and mammalian target of rapamycin (mTOR) inhibitor everolimus are approved as targeted therapies for patients with well-differentiated, non-resectable disease and evidence of disease progression. The recent approval of sunitinib for the management of advanced pNET is based on a continuous daily dosing (CDD) schedule that differs from the intermittent 4weeks on/2weeks off (4/2) schedule approved for sunitinib in advanced renal cell carcinoma (RCC) and imatinib-resistant gastrointestinal stromal tumor (GIST). Therefore, although clinicians may be familiar with therapy management approaches for sunitinib in advanced RCC and GIST, there is less available experience for the management of patients with a CDD schedule. Here, we discuss the similarities and differences in the treatment of pNET with sunitinib compared with advanced RCC and GIST. In particular, we focus on the occurrence and management of sunitinib-related toxicity in patients with pNET by drawing on experience in these other malignancies. We aim to provide a relevant and useful guide for clinicians treating patients with pNET covering the management of events such as fatigue, mucositis, hand-foot syndrome, and hypertension.

Tumeurs neuroendocrines digestives: pléomorphes et souvent ignorées [Gastrointestinal neuroendocrine tumors: pleomorphic and often ignored].

Although generally considered as rare, incidence of gastrointestinal neuroendocrine tumors (GI-NETs) is increasing. The general practitioner has thus to be familiar with the vast array of clinical presentations and the growing family of diagnostic tools that can be used. Symptoms can be related to their hormonal production, their local extent or a bleeding complication. The prognosis depends on the grade of tumor, its local extent at diagnosis and its localization. The diagnosis relies on radiologic, endoscopic and nuclear medicine strategies. In case of typical symptoms, a hormonal secretion should be sought. Treatment options are extensive and should be discussed in an interdisciplinary manner.

Positron emission tomography in the diagnosis and staging of pancreatic and neuroendocrine tumors

Tutkimuksen tausta ja tavoitteet: Viimeaikaisesta perinteisten kuvantamismenetelmien kehityksestä huolimatta sekä haima- että neuroendokriinisten (NE) kasvaimien diagnostiikka on haastavaa. Uudentyyppinen kuvantamismenetelmä, fuusio positroniemissiotomografia-tietokonetomografia (PET/TT), on lupaava näiden kasvainten erotusdiagnostiikassa ja levinneisyyden arvioinnissa. Huolimatta alustavista lupaavista tutkimustuloksista, PET/TT:n rooli on toistaiseksi vielä epäselvä sekä haima- että NE-kasvaimissa eikä se näin ollen ole vakiintunut kliiniseen hoitokäytäntöön. Väitöskirjatyön tavoitteena oli selvittää PET/TT -menetelmän käyttökelpoisuutta haima- ja NE-kasvaimien diagnostiikassa. Kahden ensimmäisen osatyön prospektiivisessa tutkimuksessa potilaat, joilla epäiltiin haimakasvainta, kuvannettiin PET/TT:llä käyttäen merkkiaineena fluorideoxyglukoosia (¹⁸F-FDG) kasvaimen aineenvaihdunnan arvioimiseksi ja kasvaimen verenvirtausta arviointiin käyttäen merkkiaineena radiovettä (¹⁵O-H₂O). Kolmen muun osatyön tavoitteena oli selvittää dihydroxyfenylalaniini (18F-DOPA) PET -menetelmää erilaisten NE-kasvaimien diagnostiikassa ja levinneisyyden arvioinnissa. Tulokset: Haimakasvaimien ensivaiheen diagnostiikassa ¹⁸F-FDG-PET/TT:llä oli korkeampi diagnostinen tarkkuus verrattuna titokoneleike- (TT) ja magneettikuvantamiseen (MK) (89% vs. 76% ja 79%). Etenkin pahanlaatuiseksi epäillyn sappitiehytahtauman erotusdiagnostiikassa ¹⁸F-FDG-PET/TT:n positiivinen ennustearvo (92%) oli korkea. Haimasyövän levinneisyyden arvioinnissa ¹⁸F-FDG-PET/TT:n herkkyys oli huono (30%) paikallisen taudin osoittamisessa. Sen sijaan etäpesäkkeiden osoittamisessa ¹⁸F-FDG-PET/TT oli merkittävästi herkempi menetelmä verrattuna TT ja magneettikuvantamiseen (88% vs. 38%). Verrattaessa erilaisten haimakasvaimien ja normaalin haimakudoksen aineenvaihduntaa ja verenvirtausta, aineenvaihdunta/verenvirtaus suhde oli merkittävästi korkeampi pahanlaatuisissa haimakasvaimissa (P<0.05). Lisäksi kasvaimen korkea aineenvaihdunta/verenvirtaus suhde viittasi huonompaan taudin ennusteeseen. ¹⁸F-DOPA-PET löysi seitsemän kahdeksasta insulinoomasta ja oli positiivinen myös kahdella potilaalla, joilla todettiin haiman saarakesoluhyperplasia. Perustuen alustaviin tuloksiin, rutiinikäytössä oleva karbidopa esilääke ennen ¹⁸F-DOPA-PET kuvantamista peitti insulinooma löydöksen kahdella potilaalla kolmesta. NE-kasvaiminen diagnostiikassa 82 potilaan aineisto osoitti ¹⁸F-DOPA PET kuvantamisen tarkkuudeksi 90%. Etenkin feokromosytoomien ensivaiheen diagnostiikassa ja NE-kasvaimen uusiutumaa epäiltäessä menetelmän tarkkuus oli korkea. Kokonaisuudessaan 59%:lla aineiston potilaista ¹⁸F-DOPA-PET kuvantamisella oli vaikutusta kliinisiin hoitoratkaisuihin. Johtopäätökset: PET/TT käyttäen merkkiaineena ¹⁸F-FDG:tä ja radiovettä osoittautui käyttökelpoiseksi menetelmäksi haimakasvaimien erotusdiagnostiikassa. Lisäksi ¹⁸F-FDG-PET/TT oli hyödyllinen haimasyövän etäpesäkkeiden arvioinnissa. Tutkimus osoitti myös ¹⁸F-DOPA-PET kuvantamisen olevan luotettava menetelmä insulinoomien ja muiden vatsan alueen NE-kasvaimien ensivaiheen diagnostiikassa sekä levinneisyyden arvioinnissa, etenkin muiden kuvantamislöydösten ollessa ristiriitaisia. PET kuvantamisella oli merkittävä vaikutus potilaiden kliiniseen hoitokäytäntöön sekä haima- että NE-kasvaimissa.

Resection of liver metastasis from neuroendocrine tumors: evaluation of results and prognostic factors

OBJECTIVES: to determine the prognostic factors that may impact on morbidity and mortality and survival of patients undergoing surgical treatment of liver metastases from neuroendocrine tumors. METHODS: We studied 22 patients undergoing liver resection for metastases from neuroendocrine tumors between 1997 and 2007. Epidemiological and clinical data were correlated with morbidity and mortality and overall and disease-free survivals. RESULTS: twelve patients were male and ten female, with a mean age of 48.5 years. Bilobar disease was present in 17 patients (77.3%). In ten patients (45.5%) the primary tumor originated in the pancreas, terminal ileum in eight, duodenum in two, rectum in one and jejunum in one. Complete surgical resection (R0) was achieved in 59.1% of patients. Eight patients (36.3%) developed complications in the immediate postoperative period, one of them dying from septicemia. All patients undergoing re-hepatectomy and/or two-stage hepatectomy had complications in the postoperative period. The overall survival at one and five years was 77.3% and 44.2%. The disease-free survival at five years was 13.6%. The primary pancreatic neuroendocrine tumor (p = 0.006) was associated with reduced overall survival. Patients with number of metastatic nodules < 10 (p = 0.03) and asymptomatic at diagnosis (p = 0.015) had higher disease-free survival. CONCLUSION: liver metastases originating from pancreatic neuroendocrine tumors proved to be a negative prognostic factor. Symptomatic patients with multiple metastatic nodules showed a significant reduction in disease-free survival.

Immunolocalization of estrogen and progesterone receptors in neuroendocrine tumors of lung, skin, gastrointestinal and female genital tracts

Expression of estrogen (ER) and progesterone (PR) receptors has traditionally been associated with hormone-responsive organs, such as breast, ovary, and endometrium, and carcinomas arising therefrom. More recently, examples of ''unexpected'' ER or PR expression have been reported, particularly in tumors of endocrine tissues, such as thyroid and pancreatic islet cells. We tested the hypothesis that neuroendocrine tumors of various primary and metastatic sites might also express ER or PR or both by performing a retrospective immunohistochemical study in a series of 59 formalin- or mechacarn-fixed neuroendocrine carcinomas of various sites, including lung, skin, gastrointestinal and female genital tracts, and including carcinoid and atypical carcinoid tumors, small cell carcinomas, and Merkel cell carcinomas. We employed the anti-ER monoclonal antibody 1D5 and the anti-PR monoclonal antibody PgR1A6 using standard immunohistochemical techniques after microwave-based heat-induced epitope retrieval. Two of 28 carcinoid tumors demonstrated ER positivity; six of 30 cases were positive for progesterone receptor only. In addition, PR expression was found in one of two cases of atypical carcinoid, in five of 25 cases of small cell carcinoma, and in one of two cases of Merkel cell carcinoma. None of the atypical carcinoids, small cell carcinomas, or Merkel cell carcinomas were ER positive. In most cases, the fraction of tumor cell nuclei that were positive was <50%. These studies add the spectrum of neuroendocrine tumors that can express these hormone receptors. Similar to the pattern previously described in the subsets of meningiomas and islet cell tumors, PR but not ER is detectable in most cases. These results underscore the caution that should be exercised in determining tissue origin of metastatic carcinomas based only on detection of hormone receptors by immunohistochemistry.

Internalized somatostatin receptor subtype 2 in neuroendocrine tumors of octreotide-treated patients

Somatostatin receptor subtype 2 (sst(2)) is widely expressed in neuroendocrine tumors and can be visualized immunohistochemically at the cell membrane for diagnostic purposes. Recently, it has been demonstrated in animal sst(2) tumor models in vivo that somatostatin analog treatment was able to induce a complete internalization of the tumor sst(2).