Biopsy of rectal carcinoid tumor is commonly taken before endoscopic resection. However the preceding biopsy can inhibit complete resection by causing blurred tumor border and fibrosis of the tissue. The objective of the study was to investigate the effect of preceding biopsy on complete endoscopic resection in rectal carcinoid tumor. It was also determined if rectal carcinoid tumors can be macroscopically distinguished by endoscopy. We reviewed retrospectively the records of patients with rectal carcinoid tumor who had undergone an endoscopic treatment at our hospital, during a 7-yr period. The resection margin was clear in 57 of 98 cases. The preceding biopsy was taken in 57 cases and the biopsy was significantly associated with the risk of incomplete tumor resection (OR, 3.696; 95% CI, 1.528-8.938, P = 0.004). In 95.9% of the cases, it was possible to suspect a carcinoid tumor by macroscopic appearance during initial endoscopy. The preceding biopsy may disturb complete resection of rectal carcinoid tumor. In most cases, the carcinoid tumor could be suspected by macroscopic appearance. Therefore the preceding biopsy is not essential, and it may be avoided for the complete resection.
Keywords: Biopsy; Carcinoid Tumor; Endoscopic Treatment; NETs; Rectal Carcinoid Tumor.