Application of light microscopical and ultrastructural immunohistochemistry in the study of goblet cell carcinoid in the appendix

Routine histological and histochemical methods were employed, with a combination of histochemistry and immunohistochemistry on one section and light and electron microscopical immunohistochemisty on paraffin-embedded material, were applied to identify the type of the carcinoid and to reveal the fine structure of cell types in the tumour nests of the appendix.During the biopsy of a patient who had undergone appendectomy, an infiltration with clusters of goblet cells in the submucosa of the appendix was found. After a second operation of right-sided hemicolectomy, similar clusters of goblet cells were detected in the muscle layers of the caecum. After 18 months the patient died from cirrhosis and had not developed metastases or any recurrence. Immunohistochemically the serotonin-, somatostatin-, chromogranin A- and synaptophysin-positive endocrine cells were basally attached to mucin-secreting cells. The combined staining revealed simultaneously present endocrine cells (chromogranin-A-positive) and mucin-secreting cells (PAS- or alcian blue-positive). The ultrastructural immunohistochemistry showed that chromogranin A-positive cells had discoid and pleomorphic granules and were located in tumour nests or as single cells in the appendiceal wall.The combined histochemical and immunohistochemical procedure and the ultrastructural immunohistochemistry on archival material could contribute in clarifying the diagnosis of goblet cell carcinoid.In the last 30 years, histochemical, immunohistochemical and electron microscopic techniques were applied in the study of carcinoids of the appendix. With the aid of previously mentioned techniques an endocrine cell component has been detected in these tumours. In clinical aspect, published articles have predominantly addressed the diagnostic procedures, progression of, and therapy for the entity [1-4].Goblet cell carcinoids appear in the appendix less frequently than other carcinoids (and constitute approximately 5% of all appendicle