Diagnostic work-up of gastroenteropancreatic neuroendocrine tumors.

Neuroendocrine tumors are a heterogeneous group of malignancies that present a diagnostic challenge. The majority of patients (more than 60%) present with metastatic disease at diagnosis. The diagnosis is based on histopathology, imaging, and circulating biomarkers. The histopathology should contain specific neuroendocrine markers such as chromogranin A, synaptophysin, and neuron-specific enolase and also an estimate of the proliferation by Ki-67 (MIB1). Standard imaging procedures consist of computed tomography or magnetic resonance imaging together with somatostatin receptor scintigraphy. 68Ga-DOTA-octreotate scans will in the future replace somatostatin receptor scintigraphy because they have higher specificity and sensitivity. Other positron imaging tomographic scanning tracers that will come into clinical use are 18F-DOPA and 11C-5HTP. Neuroendocrine tumors secrete many different peptides and amines that can be used as circulating biomarkers. The most useful general marker is chromogranin A, which is both a diagnostic and prognostic marker in most neuroendocrine tumors. However, there is still a need for improved biomarkers for early detection and follow-up of patients during treatment. In addition, molecular imaging can be further developed for both detection and evaluation of treatment.

Diagnostic work-up of gastroenteropancreatic neuroendocrine tumors

Neuroendocrine tumors are a heterogeneous group of malignancies that present a diagnostic challenge. The majority of patients (more than 60%) present with metastatic disease at diagnosis. The diagnosis is based on histopathology, imaging, and circulating biomarkers. The histopathology should contain specific neuroendocrine markers such as chromogranin A, synaptophysin, and neuron-specific enolase and also an estimate of the proliferation by Ki-67 (MIB1). Standard imaging procedures consist of computed tomography or magnetic resonance imaging together with somatostatin receptor scintigraphy. 68Ga-DOTA-octreotate scans will in the future replace somatostatin receptor scintigraphy because they have higher specificity and sensitivity. Other positron imaging tomographic scanning tracers that will come into clinical use are 18F-DOPA and 11C-5HTP. Neuroendocrine tumors secrete many different peptides and amines that can be used as circulating biomarkers. The most useful general marker is chromogranin A, which is both a diagnostic and prognostic marker in most neuroendocrine tumors. However, there is still a need for improved biomarkers for early detection and follow-up of patients during treatment. In addition, molecular imaging can be further developed for both detection and evaluation of treatment.

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.

Tratamento cirúrgico do linfoma primário do colo / Surgical treatment of primary colon lymphoma

Objetivo: analisar os resultados do tratamento cirúrgico curativo dos linfomas cólicos primários. Casuística: durante o período de 1968 até 1994, seis casos de linfomas cólicos primários foram operados com intençäo curativa. Métodos: Os critérios de Dawson foram utilizados para caracterizar o linfoma cólico como primário. No estadiamento do tumor, utilizou-se a classificaçäo de Ann Arbor para linfomas gastrintestinais modificada por Musshoff e Schmidt-Vollmer. A classificaçäo histológica utilizada foi o sistema Working Formulation Group. Resultados: dois doentes eram do sexo masculino e quatro do feminino. A média da idade foi de 50,1 anos. Em dois casos, o diagnóstico foi realizado no pré-operatório. O ceco foi envolvido em quatro doentes, a válvula ileocecal em um e o cólon ascendente em outro. Todos os doentes foram submetidos à colectomia direita radical com linfadenectomia regional. Näo houve óbito operatório. A média de sobrevivência foi de 16,5 meses e apenas um enfermo está vivo há 17 anos, sem doença ativa. Conclusöes: recomenda-se a ressecçäo da lesäo para estadiamento mais acurado, oportunidade de cura, prevençäo de complicaçöes e alívio dos sintomas. A radioterapia e/ou quimioterapia säo utilizadas para o controle da doença residual microscópica na lesäo localmente avançada, e na doença disseminada ou irressecável

Tipos histológicos de cáncer gástrico de acuerdo a la clasificación de Lauren en el Hospital Nacional Cayetano Heredia / Histological types og gastric cancer according to Layren classification in Cayetano Heredia National Hospital

Las muestras histológicas de estómago, obtenidas de 148 pacientes del Hospital Nacional Cayetano Heredia, atendidos entre enero de 1988 y diciembre de 1994, con el diagnóstico de cancer gástrico, fueron revisadas con la finalidad de clasificarlas según los criterios propuestos por Lauren. De acuerdo a esta clasificación el tipo intestinal fue el más frecuente con 99 pacientes (67 por ciento), seguido del tipo difuso con 40 pacientes (27 por ciento). Se consideró además un grupo catalogado como mixto y no clasificado con 9 pacientes (6 por ciento). Hubo predominio del sexo femenino para el tipo difuso y del sexo masculino para el tipo intestinal. Se demostró con validez estadística que a menor edad el tipo histológico que predomina es el difuso y a menor edad es el tipo intestinal. En nuestra serie no hubo diferencia estadísticamente significativa para la localización según el tipo histológico, sin embargo resalta que en los tres grupos el compromiso simultáneo de dos regiones gástricas es muy frecuente, principalmente en antro y cuerpo

Linfomas del tracto gastrointestinal: una enfermedad neoplásica del subdesarrollo / Gastrointestinal lymphomas: malignant disease of under development

Cuatrocientos cincuentaiocho de los 3,495 casos de linfoma maligno registrados entre los años 1965 y 1992 en el Instituto de Enfemedades Neoplásicas, correspondieron a Linfomas del Tracto Gastrointestinal. Esta es una de las series de linfoma del TGI más grande entre las reportadas por hospitales de cáncer, y sugiere que esta rara patología es relativamente frecuente en nuestro medio. El análisis de esta casuística muestra una mayor frecuencia relativa de la localización en el intestino delgado de esta serie comparte algunas características con el linfoma de la enfermedad inmunoproliferativa del intestino delgado descrita en las poblaciones jóvenes y pobres del Mediterraneo. La enfermedad confinada a la viscera (estadíos I y II) es curable por cirugía en 0 por ciento de casos. La enfermedad avanzada incompletamente resecada puede beneficiarse con quimioterapia complementaria. La enfermedad irresecable quirurgicamente puede ser tratada con quimioterapia complementaria de inducción sin que el riesgo de perforación o hemorragia sea prohibitivo el 50 por ciento de los casos inoperables tratados con quimioterapia alcanzaron sobrevidas a 5 y 10 años libres de recidiva de la enfermedad