[Registry of neuroendocrine tumors (NET) in Czech Republic after three years of data collection]

Neuroendocrine tumors are traditionally considered to be "rare" diseases. On contrary, the prevalence of neuroendocrine tumors is high. Therefore, the diagnostics, treatment and follow-up of neuroendocrine tumors are subjected to an evolving interest. There are various specifics of neuroendocrine tumors requiring an appropriate feedback of each intervention i.e. data collection and central data evaluation. The "Cooperative Group for Neuroendocrine Tumors" (KSPNN) has been conducting a nationwide neuroendocrine tumors registry since June 2009. The first data summary after three years is aimed at evaluation of feasibility and data utility.

The anonymous data on diagnostics, therapy and follow up of patients with neuroendocrine tumors of any primary site are collected in the registry. The contribution is conditioned by morphologically proven diagnosis according to the current WHO 2010 classification, in earlier cases WHO 2000 classification. The registry is operated by the Institute of Biostatistics and Analyses, Masaryk University (Brno). The initial analysis includes data from June 2009 to October 2012.

Data of a substantial share of neuroendocrine tumor carriers have been collected -  742 subjects with a valid record, i.e. about 14% of presumed prevalence. Moreover, the registry covers nearly one fourth of incidence in the period 2009- 2011. The morphological diagnoses with the sign of nonspecific "neuroendocrine tumors" comprise the majority of records (75%); the most frequent is "carcinoid tumor neuroendocrine tumors". This results in a clear requirement for more detailed specifications of morphology as well as separation of small cell (neuroendocrine) carcinoma possessing principal bio-logic differences to neuroendocrine tumors itself. There is an apparent polarity of recorded clinical stages. Both stage I and stage IV comprise 30% of the records. This result is presumably related to how the diagnosis is established, either early and incidentally in initial stage or late with a developed endocrine symptomatology, in advanced stage. There is an evident selection bias. The treatment data reflect current trends, dominance of surgical therapy including reasonable cytoreductive surgery, vast use of somatostatine analogues in advanced disease and persistent position of chemotherapy for high grade tumors. The distribution of treatment modalities in the records documents a certain adherence to international treatment standards (ENETS, ESMO, NCCN).

The dynamics of data contributions confirm feasibility of data collection in the registry. The registry reveals a clear requirement for more detailed analyses of biopsies and more detailed disease morphology classification. In the near future, the registry is aimed to maintain the increasing volume of collected data and to cover the majority of neuroendocrine tumors incidence.