Synchronous well differentiated neuroendocrine tumour and gastrointestinal stromal tumour of the stomach: a case report

Background: Well differentiated neuroendocrine tumours (carcinoids), arising from cells of the diffuse neuroendocrine system, represent the most commonly encountered gastric endocrine tumours. Gastrointestinal stromal tumours (GISTs), which stem from interstitial Cajal cells located within the wall of the gastrointestinal tract and have a characteristic immunoreactivity for CD117 (c-kit protein), account for the majority of gastrointestinal mesenchymal neoplasms. Simultaneous occurrence of a GIST with a well differentiated neuroendocrine tumour in the stomach is very rare. Methods: Clinical history, endoscopy and histopathological findings were utilized for our diagnostic considerations. Results: We report the coexistence of a high risk GIST with a well differentiated neuroendocrine tumour of benign clinical behavior, both located in the stomach, in a 62-year-old man previously operated for a gastric well differentiated neuroendocrine tumour with uncertain malignant behaviour. Conclusions: Even single well differentiated, sporadic, NETs of small size may coexist with GISTs. An appropriate initial therapeutic approach combined with a scrupulous follow-up seems to play a significant role in terms of preventing a metastatic disease.