Lessons learned about appendiceal neuroendocrine neoplasms from data analysis of the Belgian Cancer Registry 2010-2015
Background and study aims : Appendiceal neuroendocrine neo-plasms (aNENs) are a diverse group of malignant neoplasms ofvarying biological behavior for which information about manage-ment and outcome is sparse, with the majority of available studiesbeing retrospective, including only a limited number of patients,and therefore not necessarily reflecting the reality in the community.In the present study clinical, epidemiological and pathological dataof appendiceal neuroendocrine neoplasms in Belgium is providedand compared with current literature. Methods : A population-based study was conducted by linkingdata of the Belgian Cancer Registry with medical procedures inthe Belgian Health Insurance database for patients diagnosed withaNEN between 2010 and 2015. Results : We found an aNEN incidence of 0.97/100.000 personyears in Belgium. Neuroendocrine carcinoma of the appendix arerare. Most appendiceal neuroendocrine tumors (aNETs) are smallG1 tumors. Positive lymph nodes are often found in tumors largerthan 2cm, especially aNET G2. Conclusion : A rapid uptake of changing classifications was seenin the community. However, systematic reporting of risk factorsfor small aNEN can still be improved and should be stimulated.In 9% of cases, reclassifications had to be made, pointing out thatin a retrospective analysis, original pathological reports should bechecked for specific parameters, before reliable conclusions can be drawn.