Observational study of patients with gastroenteropancreatic and bronchial neuroendocrine tumors in Argentina: Results from the large database of a multidisciplinary group clinical multicenter study.

Neuroendocrine tumors (NET) include a spectrum of malignancies arising from neuroendocrine cells throughout the body. The objective of this clinical investigation of retrospectively and prospectively collected data was to describe the prevalence, demographic data, clinical symptoms and methods of diagnosis of NET and the treatment and long-term follow-up of patients with NET. Data were provided by the participating centers and assessed for consistency by internal reviewers. All the cases were centrally evaluated (when necessary) by the pathologists in our group. The tissue samples were reviewed by hematoxylin and eosin and immunohistochemical staining techniques to confirm the diagnosis of NET. In total, 532 cases were documented: 461 gastroenteropancreatic-NET (GEP-NET) and 71 bronchial NET (BNET). All the tumors were immunohistochemically defined according to the World Health Organization (WHO) and European Neuroendocrine Tumor Society criteria. The most common initial symptoms in GEP-NET were abdominal pain, diarrhea, bowel obstruction, flushing, gastrointestinal bleeding and weight loss. The most common tumor types were carcinoid (58.0%), non-functional pancreatic tumor (23.0%), metastatic NET of unknown primary (16.0%) and functional pancreatic tumor (3.0%). Of the BNET, 89.0% were typical and 11.0% atypical carcinoids. Of the patients with GEP-NET, 59.2% had distant metastasis at diagnosis. The locations of the primary tumors in GEP-NET were the small bowel (26.9%), pancreas (25.2%), colon-rectum (12.4%), appendix (7.6%), stomach (6.9%), esophagus (2.8%), duodenum (2.0%) and unknown primary (16.3%). The histological subtypes based on the WHO classification were well-differentiated NET (20.1%), well-differentiated neuroendocrine carcinomas (66.5%) and poorly differentiated neuroendocrine carcinomas (10.3%). Overall, 67.3% of the patients underwent surgery, 41.2% with curative intent and 26.1% for palliative purposes. The 5-year survival rates were 65.1% (95% confidence interval, 58.0-71.4%) in GEP-NET and 100.0% in typical carcinoid of the lung. This observational, non-interventional, longitudinal study aimed to accumulate relevant information regarding the epidemiology, clinical presentation and current practices in the treatment of NET patients in Argentina, providing insight into regional differences and patterns of care in this heterogeneous disease.

Chromogranin A as a biochemical marker for the management of neuroendocrine tumors: a multicenter study developed in Argentina.

Elevated circulating levels of chromogranin A (CgA) are found in the neuroendocrine tumors (NETs), but diagnostic usefulness of this marker is still debatable. To assess the role of CgA for the identification and follow up of gastroenteropancreatic neuroendocrine tumors (GEP-NET), a multicenter prospective longitudinal study has been carried out in Argentina. CgA was measured by RIA in 119 histologically proven GEP-NET patients and in 39 healthy controls. A cutoff value of 2.8 nmol/L was established from a receiver-operating characteristic (ROC) curve, as discriminating between controls and patients with active disease (specificity 100% and sensitivity 92.3%). CgA levels were higher in functioning than in no functioning tumors (median 55 nmol/L vs 5 nmol/L, p < 0.05). Metastases were present in 83 patients and their CgA levels were significantly higher than levels in the 36 patients without metastases (median 44 nmol/L vs 64 nmol/L, p < 0.0001). CgA levels are strongly correlated with tumor metastatic spread. Sensitivity differed between patients with localized disease (median 6 nmol/L), extensive disease (median 22 nmol/L) and very extensive disease (median 44 nmol/L) (p < 0.001). In conclusion, due to its high sensitivity and specificity, CgA is useful in a newly discovered GEP-NET especially when no abnormal hormone secretion can be demonstrated. CgA levels were significantly higher in functioning tumors than in non-functioning tumors and increased with metastatic spread. If serial evaluation of CgA levels is sufficient for the detection of tumor growth changes remains to be prospectively demonstrated.

Biopsias guiadas por marcación radioisotópica para alteraciones costales solitarias presuntivamente neoplásicas / Radioisotope-guided rib biopsies in suspected neoplastic patients

Antecedentes: El centellograma óseo se usa rutinariamente para estadificación y seguimiento de tumores malignos, especialmente de aquellos que con frecuencia dan origen a metástasis esqueléticas. Anormalidades costales múltiples alejadas de las articulaciones, son generalmente compatibles con metástasis. Pero por otro lado, un sitio solitario de hipercaptación puede no ser debido a la ya conocida enfermedad neoplásica, sino a un proceso benigno coexistente. Para evaluar la significación de este hallazgo, debe llevarse a cabo una biopsia a cielo abierto. Objetivo: Evaluar las biopsias radioguiadas, y la significación de un foco solitario de hipercaptación costal en pacientes neoplásicos o sospechosos de serlo. Lugar de aplicación: Centro oncológico universitario público. Diseño: Retrospectivo. Población: 23 pacientes con lesiones costales solitarias sospechosas de ser neoplásicas primitivas o bien metastásicas de tumores en actividad en algunos casos, o presumiblemente controlados en otros...

Biopsias guiadas por marcación radioisotópica para alteraciones costales solitarias presuntivamente neoplásicas / Radioisotope-guided rib biopsies in suspected neoplastic patients

Antecedentes: El centellograma óseo se usa rutinariamente para estadificación y seguimiento de tumores malignos, especialmente de aquellos que con frecuencia dan origen a metástasis esqueléticas. Anormalidades costales múltiples alejadas de las articulaciones, son generalmente compatibles con metástasis. Pero por otro lado, un sitio solitario de hipercaptación puede no ser debido a la ya conocida enfermedad neoplásica, sino a un proceso benigno coexistente. Para evaluar la significación de este hallazgo, debe llevarse a cabo una biopsia a cielo abierto. Objetivo: Evaluar las biopsias radioguiadas, y la significación de un foco solitario de hipercaptación costal en pacientes neoplásicos o sospechosos de serlo. Lugar de aplicación: Centro oncológico universitario público. Diseño: Retrospectivo. Población: 23 pacientes con lesiones costales solitarias sospechosas de ser neoplásicas primitivas o bien metastásicas de tumores en actividad en algunos casos, o presumiblemente controlados en otros...(AU)