Local surgical excision versus endoscopic resection for rectal carcinoid: A meta-analysis

Development of a novel scoring system based on endoscopic appearance for management of rectal neuroendocrine tumors

BACKGROUND

The clinical significance of the endoscopic appearance of rectal neuroendocrine tumors (NETs) is poorly understood. We aimed to develop a novel scoring system based on endoscopic appearances to predict endoscopically advanced disease in patients with rectal NETs when initially diagnosed.

METHODS

Patients diagnosed with well-differentiated rectal NETs between January 2005 and December 2019 were retrospectively included. Logistic regression analyses were applied to study the relationship between endoscopic appearance and advanced disease. The whole dataset was randomly divided into training and validation sets, which were used to develop and validate a novel scoring system, respectively.

RESULTS

309 patients were included. The endoscopic appearance of rectal NETs was significantly associated with advanced disease (P < 0.001). A novel scoring system was developed based on endoscopic appearance, including tumor size, tumor shape, and mucosal surface, using the training set. The area under curve (AUC) of the scoring system to predict advanced disease was 0.953 (95 % confidence interval [CI] 0.915 - 0.991; P < 0.001) and 0.960 (95 %CI 0.905 - 1.000; P < 0.001) in the training and validation sets, respectively. Furthermore, the scoring system was significantly associated with tumor grade. Patients with high scores had significantly worse disease-free and overall survival than patients with low scores (P < 0.001).

CONCLUSION

This novel scoring system based on the endoscopic appearance of the primary tumor can help to accurately identify patients with endoscopically advanced disease who are not suitable for endoscopic resection. In addition, it is of great value in monitoring tumor recurrence and overall survival in patients with rectal NETs.

Oncological outcomes according to the treatment modality based on the size of rectal neuroendocrine tumors: a single-center retrospective study

BACKGROUND

Owing to an increased number of colonoscopy screenings, the incidence of diagnosed rectal neuroendocrine tumors (NETs) has also increased. Tumor size is one of the most frequently regarded factors when selecting treatment; however, it may not be the determinant prognostic variable. We aimed to evaluate oncological outcomes according to the treatment modality based on the size of rectal NETs.

METHODS

A retrospective analysis was performed on patients who were treated for rectal NETs between March 2000 and January 2016 at the Asan Medical Center, Seoul, Korea. Patients who underwent endoscopic removal, local surgical excision, and radical resection were included. The primary outcome was recurrence-free survival (RFS). Data were specified and analyzed following the 2019 World Health Organization classification (WHO).

RESULTS

A total of 644 patients were categorized under three groups according to the treatment modality used: endoscopic removal (n = 567), surgical local excision (n = 56), and radical resection (n = 21). Of a total of 35 recurrences, 27 were local, whereas eight were distant. The RFS rate did not differ significantly between the treatment groups in the same tumor-size group ([Formula: see text]1 cm group: P = .636, 1-2 cm group: P = .160). For T1 tumors, RFS rate was not different between local excision and radical resection ([Formula: see text]1 cm group: P = .452, 1-2 cm group: P = .700). Depth of invasion, a high Ki-67 index, and margin involvement were confirmed as independent risk factors for recurrence. Among patients treated with endoscopic removal, endoscopic biopsy was a significant factor for worse RFS (P < .001), while tumor size did not affect the RFS.

CONCLUSION

The current guideline recommends treatment options according to tumor size. However, more oncologically important prognostic factors include muscularis propria invasion and a higher Ki-67 index.

Efficacy and safety of hybrid endoscopic submucosal dissection compared with endoscopic submucosal dissection for rectal neuroendocrine tumors and risk factors associated with incomplete endoscopic resection

Background

Neuroendocrine tumors (NETs) are rising in prevalence, particularly with the rectal area. This study evaluated and compared the safety and effectiveness of hybrid endoscopic submucosal dissection (ESD) with those of ESD for rectal NETs and risk factors associated with incomplete endoscopic resection.

Methods

A total of 272 consecutive patients who underwent ESD or hybrid ESD for rectal NETs at the Chinese PLA General Hospital in the period from February 2011 to September 2018 were involved in this study. Data were collected from clinical and endoscopic databases. The procedure time, en bloc resection, complete resection, complication, and recurrence rates were evaluated.

Results

In the hybrid ESD group were 111 patients (who had 119 lesions between them), with a further 161 patients (164 lesions) in the ESD group. No significance was found in baseline characteristics between the two groups. Hybrid ESD had a significantly shorter mean procedure time than ESD (13.2±8.3 vs. 18.1±9.7 min, P=0.000). Hybrid ESD showed similar en bloc resection (99.2% vs. 98.2%; P=0.373), complete resection (94.1% vs. 90.9%, P=0.641), and postprocedural bleeding (2.5% vs. 0.6%, P=0.313) rates to ESD. Univariate and multivariate analysis showed that higher histopathological grade was associated with incomplete resection.

Conclusions

For rectal NET, both ESD and hybrid ESD are effective and safe forms of treatment. Hybrid ESD provides an alternative option in the treatment of rectal NETs. Further developments are needed to improve the complete resection rate, especially concerning tumors with higher histopathological grade.

Association between loss of heterozygosity of chromosome 16q and survival in Wilms' tumor: A meta-analysis

BACKGROUND

Wilms' tumor (WT) is the most common pediatric renal tumor. Despite its high survival rate, the potential prognostic factors should further be studied to reduce the intensity of the treatment. A few studies have found LOH of 16q is associated with worse survival in patients with WT, but it is still contradictory. This study aimed to performed a meta-analysis to clarify this.

METHODS

Databases including the Wanfang, PubMed, Chinese National Knowledge Infrastructure, Embase, and Cochrane Library databases were searched July 2018. The meta-analysis was done using Stata (version 14.0). Publication bias was evaluated by funnel plots, Begg's test, and Egger's test. The trim-and-fill method was applied if significant publication bias existed. Sensitivity analysis was performed to evaluate the stability of the results.

RESULTS

This meta-analysis identified 9 cohort studies encompassing 3266 cases. The pooled relative risk when comparing LOH of 16q groups with control groups was 2.22 [95% confidence interval (CI) = 1.64-3.00, P < 0.001], and the pooled hazard ratio was 1.92 (95%CI = 1.32-2.80, P = 0.001). The results were stable after correcting for publication bias and performing a leave-one-out sensitivity analysis.

CONCLUSIONS

This meta-analysis indicated that LOH of 16q was significantly associated with worse survival in WT. Further studies need to identify this conclusion because the overall quality of the included studies is not high, investigate the impact of LOH of 16q on the survival of WT patients in different subgroups and identify better treatments for WT patients with LOH of 16q in order to lengthen their survival.