Endoscopically identified well-differentiated rectal carcinoid tumors: impact of tumor size on the natural history and outcomes

ENETS Consensus Guidelines Update for Colorectal Neuroendocrine Neoplasms

“…3 In a single-center retrospective series from Baltimore, Md., USA [4], no metastases were seen in lesions ≤9 mm, and this follows the previous ENETS recommendations guiding investigations, outcomes and therapeutic options based on cut-off sizes of 10 and 20 mm. The occurrence of multiple rectal NENs was also noted by Park et al [5] who recommended full colonoscopy in the presence of one colorectal NEN.…”

“…They found that tumor size and depth predicted lymph node metastasis and showed that intramucosal tumors <1 cm have a 4% risk of lymph node metastasis. Tumors <10 mm had a 3% risk of metastasis in the Baltimore group [4], and while the risk is not zero for small tumors, the majority of patients appear cured once full resections of small (<10 mm) rectal NENs with favorable biology are performed. Predictors of survival were further examined by Weinstock et al [7] who showed that stage was the strongest predictor of survival in multivariate analysis and that grade, size, symptoms and treatment modality were only significant in univariate analysis.…”

Nowotwory neuroendokrynne jelita grubego — zasady postępowania (rekomendowane przez Polską Sieć Guzów Neuroendokrynnych)

“…Radical resection is also recommended in the presence of other risk factors for the regional lymph nodes, such as: high tumour mitotic index (G2, G3, Ki-67 > 2%), invasion of lymphatic and blood vessels, or positive expression of HES77 [33,34].…”

Hindgut Neuroendocrine Neoplasia

“…This can be achieved endoscopically either by polypectomy, endosciopic mucosal resection or endoscopic submucosal dissection. [12] If this is not possible the tumors can be removed surgically via the anal canal either by TransAnal Excision (TAE), Transanal Endoscopic MicroSurgery (TEMS) of Trans-Anal Minimally Invasive Surgery (TAMIS). For tumors that are greater than 2 cm patients should undergo a rectal resection with a Total Mesorectal Excision (TME) either by anterior resection or abdomino-perineal resection.…”

“…(Table 2) The size of the tumor is the greatest factor associated with metastatic disease. [12] As metastatic hindgut WNET tumors are rare treatment is extrapolated from metastatic disease of the more common midgut and forgut metastatic WDNET. The most common site of metastatic disease is the liver with other sites including the lung and retroperitoneal lymph nodes.…”