title: Clinical and histopathological tumour progression in ECL cell carcinoids ("ECLomas").
abstract: OBJECTIVE
  The aims of this study were to illustrate the malignant potential of gastric enterochromaffin-like (ECL) cell carcinoids (ECLomas) associated with hypergastrinemia, and the gradual neoplastic progression of such tumours. In addition, we examined whether the tyramide signal amplification (TSA) technique could visualize immunohistochemical (IHC) neuroendocrine (NE) features in the dedifferentiated neoplastic ECL cells which were not detected by conventional methods.
  
  
  METHODS
  Conventional histopathological and IHC methods for visualizing ECL cells and cell proliferation were used in addition to the TSA technique.
  
  
  METHODS
  Our patient was followed for 5 years. During that period, her ECLoma displayed all the signs of classical tumour progression, ultimately with the appearance of metastases in the regional lymph nodes, the liver and the skin. The neoplastic ECL cells became progressively dedifferentiated with an increasing number of Ki-67 immunoreactive (IR) cell nuclei. In addition, there was a substantial decrease in argyrophil and IR NE cells that could be visualized by conventional methods. By applying the TSA technique, however, the number of IR tumour cells increased considerably.
  
  
  CONCLUSIONS
  ECLomas secondary to hypergastrinemia should be closely followed for signs of clinical and histopathological tumour progression. Such ECLomas deserve early, active, radical surgical treatment. The TSA technique is a valuable tool for visualizing the characteristic IHC features in dedifferentiated NE cells.
authors.affiliation: Norwegian University of Science and Technology, Faculty of Medicine, Department of Medicine, University Hospital of Trondheim, Norway.
authors.forename: G
authors.initials: G
authors.lastname: Qvigstad
authors.forename: S
authors.initials: S
authors.lastname: Falkmer
authors.forename: B
authors.initials: B
authors.lastname: Westre
authors.forename: H L
authors.initials: HL
authors.lastname: Waldum
mesh_terms: D000368:Aged; D002276:Carcinoid Tumor / Q000378:metabolism / Q000473:pathology* / Q000556:secondary; D002454:Cell Differentiation; D053379:Chromogranin A; D002864:Chromogranins / Q000378:metabolism; D004759:Enterochromaffin Cells / Q000473:pathology; D005260:Female; D005755:Gastrins / Q000097:blood; D005757:Gastritis, Atrophic / Q000150:complications; D006640:Histidine Decarboxylase / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism; D013274:Stomach Neoplasms / Q000209:etiology / Q000378:metabolism / Q000473:pathology*
chemical_list: D053379:Chromogranin A; D002864:Chromogranins; D005755:Gastrins; D019394:Ki-67 Antigen; D012701:Serotonin; D006640:Histidine Decarboxylase