Neuroendocrine tumors of the gastrointestinal tract: a descriptive study
B. León de Zayas, M. del Olmo García, A. Ramos Prol, M. Argente Pla, M. Muñoz Vicente, A. Gilsanz Peral & J. Merino Torres
Introduction and objective: Neuroendocrine tumors (NETs) are relatively rare tumors. The majority are located in the gastrointestinal (GI) tract and bronchopulmonary system. The aim of this report is to study the characteristics of gastrointestinal NETs at diagnosis.
Material and methods: Descriptive study about 18 patients diagnosed of gastrointestinal NETs during 19932011 in our hospital. Data regarding demographic, clinical, analytical, anatomopathological and diagnostic variables were collected. Statistical analysis was perfomed using SPSS 18.0, results are expressed as mean±S.D.
Results: Eighteen patients (50% men) with a mean age at diagnosis of 52.7±14.4 years were studied. Seven (38.9%) presented typical carcinoid clinical syndrome. The rest presented symptoms due to growth of the primary tumor such as appendicitis, intestinal obstruction or diffuse abdominal pain. The mean time since symptoms appeared until diagnosis was 10 months. The ileum was the most common location (61.1%) followed by stomach (16.7%), appendix (11.1%), rectum (5.6%) and colon (5.6%). Eleven (61.1%) had metastases at diagnosis, all of them hepatic. Six of the seven patients with carcinoid syndrome presented metastases at diagnosis. Tumors were diagnosed more frequently by CT scan (50%), ultrasound (16.6%) and MRI (5.5%). Inmunohistochemical markers resulted positive for: chromogranin A (88.9%), enolase (61.1) synaptophysin (44.4%) and cytokeratin (33.3%). Ki67 was determinated in 50% of cases. It was <3% in seven cases (38.9%) and >20% in two (11.1%). The mitotic rate was determinated only in four patients (22.2%), in three of them was <2% (16.7%) and between 2 and 20% in one case (5.6%).
Conclusions: The ileum is the most common location of NETs of gastrointestinal tract. The mitotic and proliferation rate must be a priority in the anatomopathological study as it may condition different therapeutical approaches. In our serie these tumors are diagnosed in an advanced metastasic stage probably due to a low suspicion of these tumors.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.