Emic tertiary hospitals with an established experience in the management of NEN patients. The registry was funded by IPSEN Epe, Greece. IPSEN had no influence on the setup of the database, data acquisition or data analysis and had no access toA dedicated database software (TMS, Athens, Greece) was built with contribution by all authors during three specifically dedicated days. The items to be included were decided upon by specialists (medical oncologists, gastroenterologists and endocrinologists) experienced in the care of patients with NEN. This prospective survey was Staurosporine conducted in eight Greek referral centers and recruitment of NEN patients was started after October 2010. The feasibility and utility of the database was tested in a pre-test platform and necessary modifications were performed. The resulting database consisted of data fields divided in 18 sections including demographics, symptoms, tumor characteristics, diagnostic procedures, treatments modalities and outcome. If a patient received a treatment (e.g. somatostatin analogues) for more than one continuous treatment period, then the separate treatment periods and the response to each of them were documented as separate outcomes. Possible answers were either split into "yes" or "no" or selected from a drop-down menu. All physicians were trained and were responsible for the introduction of the studied features in the registry. One trained study monitor visited each center, reviewed the patients' medical files provided by the institution and assessed the quality of data insertion to the database. All patients were entered in the database, by trained doctors, with their initials, date of birth and date of histopathology diagnosis to exclude the possibility of more than one recordings of the same patient. Once the duplicates were removed this information was excluded. In the case of genetic syndrome data acquisition depended on its positive documentation of items. If for example multiple endocrine neoplasia (MEN) was documented either as a report of the genetic analysis or stated as diagnosis by the physician, the patient was documented as `MEN-positive'. In the database inserted parameters included also details on the diagnostic procedures and therapies applied. Patient data were specifically checked to avoid double insertions from different centers and in that case data were merged.Nikou et al. BMC Endocrine Disorders (2016) 16:Page 3 ofPatient inclusionTable 1 Clinicopathologic characteristics of the study populationN ( ) Primary site Gastrenteropancreatic Stomach Corpus Antrum Fundus Pancreas 156 (63.4) 54 (35 ) 37 (68.5) 11 (20.4) 6 (11.1) 36 (23 ) 20 (55.6) 10 (27.8) 6 (16.7) 8 (5 ) 5 (3 ) 10 (6 ) 17 (11 ) 8 (5 ) 18 (12 )cInclusion criteria were diagnosis of NEN histologically confirmed after October 2010 and a patient's signed informed consent. Patients were excluded if they had a small or large cell lung cancer histology or if they were not actively followed up. Histological classification applied was the WHO 2010 classification [2] and staging was assessed according to the 7th AJCC Staging system [14].Statistical analysisWe performed an interim analyses after two years of patient recruitment PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/17139194 in the registry. Continuous variables were expressed either with the use of the mean and the standard deviation or with the median and the minimum and maximum values depending on their distribution. The normality of the distribution of values was examined with the use of the Sh.