Evaluation of colonoscopy in the diagnosis and treatment of rectal carcinoid tumors with diameter less than 1 cm in 21 patients

Abstract

The aim of this study was to evaluate colonoscopy in the diagnosis and treatment of rectal carcinoid tumors with diameter <1 cm. Elevated lesions with normal mucosal appearance under colonoscopy were identified. Endoscopic ultrasound (EUS) was performed in 16 patients. Lesions diagnosed as rectal carcinoid tumors were resected by endoscopic mucosal resection (EMR). The diagnosis of specimens by EMR was confirmed by pathological examination. Immunohistochemical staining was undertaken and follow-up data were collected. Twenty-two lesions were found among the 21 cases. The majority of these were located within 10 cm of the anal opening. Twenty two cases with rectal carcinoids were diagnosed by EUS under colonoscopy and all cases were verified by pathological examination. The resection rate was 95.5% (21/22). Of the lesions, six were mucosal and 10 were submucosal. Immunohistochemistry was undertaken for carcinoid tumors. Histological patterns of rectal carcinoids revealed solid nests or trabecular patterns. Eleven cases were synaptophysin (SYN)-positive, 8 cases were neurone-specific enolase (NSE)-positive and 5 cases were chromogranin A (CgA)-positive. Colonoscopy combined with EUS is effective in the diagnosis and determination of small rectal carcinoids. Endoscopic treatment is effective for small-sized tumors. Pathology and immunohistochemistry remain the diagnostic gold standard.

Clinical impact of endoscopic ultrasonography for small rectal neuroendocrine tumors

“…None of the lesions penetrated the submucosa or showed adjacent lymph node metastasis. Some studies reported that rectal NETs ≤10 mm in size that were examined by EUS before endoscopic resection were correctly diagnosed as confined to the submucosa (6,14,20). Although EUS is a useful method for evaluating the depth of invasion, its necessity is questionable in cases of rectal NETs ≤10 mm in size.…”

Rectal carcinoid tumor: diagnosis and management

“…Endoscopic ultrasonography is used to determine the depth of the invasion, which is a very important variable in the case of a local resection. 9 The invasion or non-invasion of the muscular mucosa determines whether endoscopic excision is sufficient or if surgery is necessary in cases of endoscopically resected rectal carcinoids. It is generally indicated that lesions smaller than 1 cm in diameter can be adequately treated by endoscopic resection in case of negative margins after histological evaluation.…”

“…It is generally indicated that lesions smaller than 1 cm in diameter can be adequately treated by endoscopic resection in case of negative margins after histological evaluation. 2,9,10 Another approach is transanal local excision, as 75% of rectal tumors are located in the mid-and lower thirds of the rectum. Anterior abdominal resection or abdomino-perineal amputation of the rectum have also been indicated in lesions larger than 2 cm in diameter.…”

“…Anterior abdominal resection or abdomino-perineal amputation of the rectum have also been indicated in lesions larger than 2 cm in diameter. 2,9,10 Treatment and prognosis depend on tumor size, staging, degree, resectability, and distant metastases. In the case of localized tumors, surgical resection should be performed if the tumor is resectable.…”

Endoscopic ultrasonography is useful in the diagnosis and treatment of rectal neuroendocrine neoplasms: a case series

“…In recent years, rectal NENs are increasingly frequently detected, with the widespread availability and accessibility of endoscopy and cross-sectional imaging modalities (Kos-Kudla et al, 2017). Multiple studies have shown that endoscopic ultrasound (EUS) is an advanced endoscopic technique and is currently used in the diagnosis and preoperative assessment of NENs (Kim, 2012;Liu et al, 2013;Zhang et al, 2017). However, EUS imaging of rectal NEN and differential diagnosis with other submucosal tumors (SMTs) has not been adequately reported.…”