Appendiceal Neuroendocrine Tumors (Carcinoid of the Appendix) in Childhood: A Clinical Report From the Italian Trep Project.

BACKGROUND:: Neuroendocrine tumors (NETs) of the appendix are slow-growing tumors and, although rare, they are the most common G-I epithelial tumors in childhood and adolescence. The treatment and the follow-up screenings have not been standardized. Above all, though tumor size is considered the main prognostic variable to define the aggressiveness of approach, it remains to be established a precise cut-off. METHODS:: 113 patients under 18 years of age with a diagnosis of appendiceal NETs were registered as of 1 January 2000 until 30 May 2013 within the TREP Project (Rare Tumors in Pediatric Age), an Italian multi-institutional network dedicated to very rare tumors in children and adolescents. The recommendations of the TREP study included imaging and laboratory investigations. The treatment after appendectomy was decided on the basis of histology, tumor size and imaging: primary re-excision (PRE) was not recommended in completely excised tumors, regardless of tumor size and invasiveness. RESULTS:: 113/113 had a diagnosis of well differentiated NETs: in 108/113 the tumor was smaller than 2 cm and in 5 larger than 2. Excision margins were free in 111/113 patients. In 3/113 a PRE was performed: in 1 residual tumor was detected. 113/113 patients are alive in complete remission (median follow-up of 41 months). CONCLUSIONS:: Reported data and our experience showed that no relapse or death occurred in children and adolescents affected by appendiceal NETs. Appendectomy alone should be considered curative for most patients and a more aggressive surgical approach is deserved in those cases with incompletely excised tumors.