PD-007 Clinical outcome of Endoscopic Resection of Rectal Neuroendocrine Tumor- NET registry multicenter study

Abstract

Introduction: Rectal neuroendocrine tumor (NET) incidence is low. The previous studies of Endoscopic treatment in rectal NET have limitation because of small sample size. The aim of this study was to investigate effectiveness of endoscopic treatment in rectal NET below 2 cm. Methods: From Jan. 2003 to Dec. 2012. 1366 patients diagnosed Rectal NET in 24 centers were enrolled. Inclusion criteria were endoscopic treatment, below 2cm size, over 18 age. Exclusion criteria included no treatment, operation, chemotherapy, octreotide therapy, incomplete data. After exclusion, 411 patients were enrolled. We analyzed the clinicopathologic data and factors affecting incomplete resection. We used Chi-square, t-test statistically. Results: In total 411 patients, Age was 49.64 ± 11.33, Male were 238(57.9%), All symptom were 59(14.4%), Carcinoid symptom were 13(3.2%), Family history of NET were 4(1%), Multiple lesion were 15(3.6%), Elevated /Flat/Depressed lesions were 407 (99)/2(0.5%)/2(0.5%), Lesion size was 0.58 ± 0.32cm, In histology,Well differentiated neuroendocrine tumor/Well differentiated neuroendocrine carcinoma were 403 (98.1%)/8(1.9%), Mucosa/Submucosa/Proper muscle invasion were 117(28.5%)/288 (70.1%)/6(1.5%), Lymphovascular invasion were 4(1%), EMR/ESD were 300(73%)/111 (27%), Complete/Incomplete resection were 344(83.7%)/67(16.3%), Additional treatment after incomplete resection were 5(1.5%), Recurrence were 8(1.9%). The lymphovascular invasion, ESD was significant factor in incomplete resection. Conclusion:We suggest endoscopic treatment was effective in rectal neuroendocrine tumor below 2 cm size. And EMR is not inferior to ESD. But further study including complication result will be needed.