Published online Mar 21, 2017. doi: 10.3748/wjg.v23.i11.2037
Peer-review started: December 9, 2016
First decision: January 10, 2017
Revised: January 24, 2017
Accepted: February 17, 2017
Article in press: February 17, 2017
Published online: March 21, 2017
Processing time: 101 Days and 10 Hours
To evaluate the importance of endoscopic ultrasonography (EUS) for small (≤ 10 mm) rectal neuroendocrine tumor (NET) treatment.
Patients in whom rectal NETs were diagnosed by endoscopic resection (ER) at the Pusan National University Yangsan Hospital between 2008 and 2014 were included in this study. A total of 120 small rectal NETs in 118 patients were included in this study. Histologic features and clinical outcomes were analyzed, and the findings of endoscopy, EUS and histology were compared.
The size measured by endoscopy was not significantly different from that measured by EUS and histology (r = 0.914 and r = 0.727 respectively). Accuracy for the depth of invasion was 92.5% with EUS. No patients showed invasion of the muscularis propria or metastasis to the regional lymph nodes. All rectal NETs were classified as grade 1 and demonstrated an L-cell phenotype. Mean follow-up duration was 407.54 ± 374.16 d. No patients had local or distant metastasis during the follow-up periods.
EUS is not essential for ER in the patient with small rectal NETs because of the prominent morphology and benign behavior.
Core tip: Small rectal neuroendocrine tumors (NETs; ≤ 10 mm) that are confined to the mucosa or submucosa can be managed by endoscopic resection because of their low risk of metastatic spread. According to the 2015 guidelines of the National Comprehensive Cancer Network, when we evaluate rectal NET, endorectal magnetic resonance or endoscopic ultrasonography (EUS) is recommended. However, EUS may not be essential for evaluation of small rectal NET because of its prominent morphology and benign behavior.