A tailored approach for endoscopic treatment of small rectal neuroendocrine tumor

Introduction: Resection of rectal neuroendocrine tumors (NETs) less than 1 cm in diameter can be performed using various endoscopic techniques. Endoscopic mucosal resection (EMR) traditionally had suboptimal complete resection rate compared to endoscopic submucosal resection with band ligation (ESMR-L). However, the previous studies did not consider the characteristics of rectal NETs. The aim of our study is to compare the efficacy of ESMR-L and EMR using tailored approach according to the characteristics of rectal NETs.

Methods: 82 rectal NETs in 77 patients treated by ESMR-L (n = 48) or EMR (n = 34) between September 2007 and October 2012 were retrospectively analyzed. ESMR-L was used for flat-type tumors or tumors with non-lifting sign after submucosal injection. Conventional EMR was used for elevated-type tumors or tumors with well-lifting sign after submucosal injection.

Results: The pathological complete resection rate was higher in the ESMR-L group (45 lesions, 93.8 %) compared with the EMR group (30 lesions, 88.2 %); however, this difference was not significant (p = 0.441). Overall complication did not differ significantly between the ESMR-L group and the EMR group (p = 0.774). There was one case of a remnant lesion in the ESMR-L group, which was managed by EMR after circumferential pre-cutting (EMR-P), and no recurrence has been detected in either the ESMR-L or EMR group.

Conclusions: ESMR-L and EMR procedures could have a similar excellent complete resection rate, if we select the endoscopic resection technique according to the characteristics of the small rectal NETs.