Local excision versus radical resection in patients with rectal neuroendocrine tumours: a propensity score match analysis

Long-term outcomes of 1-2 cm rectal neuroendocrine tumors after local excision or radical resection: A population-based multicenter study

Objectives

Studies on rectal neuroendocrine tumors (R-NETs) that are 1-2 cm in size are limited, and the optimal treatment for these tumors is not well established.

Methods

Data from patients with primary localized R-NETs 1-2 cm in size were retrospectively collected from 17 large-scale referral medical centers in China. Long-term prognosis, quality of life (QOL), and fecal incontinence were evaluated, and the effects of local excision (LE) or radical resection (RR) were elucidated using propensity score matching (PSM).

Results

A total of 272 patients were included in this study; 233 underwent LE, and the remaining 39 underwent RR. Patients in the LE group showed lower tumor location, fewer postoperative Clavien-Dindo III-V complications, more G1 tumors, and lower tumor stage. There were no significant differences in the relapse-free survival or overall survival (OS) between the LE and RR groups after PSM. Patients in the LE group reported superior physical, role, emotional, social, and cognitive functions, global QOL, and Wexner fecal incontinence scores compared with those in the RR group (all P < 0.050). Eighteen (6.6%) patients had lymph node metastases. Multivariable analysis revealed that tumor location (odds ratio [OR] = 3.19, 95% confidence interval [CI] 1.04-10.07, P = 0.010), neutrophil-to-lymphocyte ratio (NLR) > 1.80 (OR = 4.50, 1.46-15.89, P = 0.012), and T3-T4 (OR = 36.31, 95% CI 7.85-208.62, P < 0.001) were independent risk factor for lymph node metastasis.

Conclusions

R-NETs measuring 1-2 cm generally have a favorable prognosis, and there is no difference in postoperative survival between LE and RR. For patients without lymph node metastasis, LE should be the preferred choice; however, for patients with a higher tumor location, preoperative NLR >1.8 or T3/T4 tumors, RR should be considered.

Comparison between Endoscopic Submucosal Dissection and Transanal Endoscopic Microsurgery in Early Rectal Neuroendocrine Tumor Patients: A Meta-Analysis

PURPOSE

To compare the effectiveness, safety and cost-effectiveness of endoscopic submucosal dissection (ESD) with transanal endoscopic microsurgery (TEM) in early rectal neuroendocrine tumor (RNET) patients. This article will provide reliable evidence for surgeons in regards to clinical decision-making.

METHODS

Systematic literature retrieval was performed in Pubmed, Embase and Cochrane database from 2013/4/30 to 2023/4/30. Methodology validation was performed by using the Newcastle-Ottawa Scale (NOS). Data-analysis was conducted by using the Review manager version 5.3 software.

RESULTS

A total of three retrospective studies were included in our meta-analysis. All eligible studies were considered to be high quality. By comparing baseline characteristics between TEM and ESD, patients in the TEM group seemed to be characterized by a larger tumor size and lower tumor level, even though no statistical significance was found. Clear statistical significance favoring TEM was identified in terms of R0 resection rate, procedure time and hospital stay. No statistical significance was found in terms of recurrence rate, adverse events rate and additional treatment rate.

CONCLUSIONS

Compared with ESD, TEM was a more effective treatment modality for early RNET patients; it was associated with a relatively higher R0 resection rate and a similar degree of safety. However, the relatively higher cost and complicated manipulation restricted the promotion of TEM. Surgeons should opt for TEM as a primary treatment in patients with a larger tumor size and deeper degree of tumorous infiltration if the financial condition and hospital facility permit.

Rectal neuroendocrine tumors: Can they be observed?

BACKGROUND

Studies comparing approaches to managing rectal neuroendocrine tumors are underpowered by institutional series. The efficacy of expectant management relative to local excision and radical resection is poorly defined.

METHODS

We queried the National Cancer Database to identify patients presenting with non-metastatic rectal neuroendocrine tumors between 2004 and 2019. Multivariable regression was used to identify factors associated with expectant management. Cox modeling was used to identify factors associated with all-cause mortality. Patients undergoing expectant management were 1:1:1 propensity score matched for demographics and comorbid disease to those undergoing radical resection and local excision. The Kaplan-Meier method was used to compare overall survival profiles for matched cohorts.

RESULTS

A total of 6,316 patients met the inclusion criteria. Of these, 5,211 (83%) underwent local excision, 600 (9.5%) radical resection, and 505 (8%) expectant management. On multivariable regression, factors associated with expectant management included Black race, government insurance, and tumor size <2.0 centimeters. On Cox modeling, factors associated with mortality included age >65 years, male sex, government insurance, comorbidity score >0, tumor size >2 centimeters, and poorly differentiated histology. On comparison of matched cohorts: patients undergoing radical resection had longer hospitalizations and higher readmission rates than those undergoing local excision; there was no difference in overall survival between cohorts in patients with stage 1 disease; in stage 2 and 3 diseases, patients undergoing local excision and radical resection demonstrated improved rates of overall survival relative to those undergoing expectant management.

CONCLUSION

Expectant management is a reasonable approach for patients with stage 1 rectal neuroendocrine tumors. Local excision should be the preferred treatment option for those presenting with stage 2/3 disease.

Prognosis for Poorly Differentiated, High-Grade Rectal Neuroendocrine Carcinomas

INTRODUCTION

Rectal neuroendocrine carcinomas (rNECs) are poorly characterized and, given their aggressive nature, optimal management is not well-established. We therefore sought to describe clinicopathologic traits, treatment details, and survival patterns for patients with rNECs.

METHODS

Patients captured in the National Cancer Database (NCDB; 2004-2016) with rNECs managed with observation, chemotherapy, or proctectomy ± chemotherapy were considered for analysis.

RESULTS

The inclusion criteria were met by 777 patients. Mean age was 62.4 years, 45% were male, 80% were Caucasian, 40% presented with lymph nodes metastases, and 49% presented with distant metastases. Chemotherapy and surgical resection were administered in 72 and 19% of cases, respectively. Median overall survival (OS) was 0.83 years (1 year, 41%; 3 years, 13%; 5 years, 10%). During the study interval, 659 (85%) patients died, with a median follow-up of 0.79 years. On multivariable analysis, age ≥60 years, male sex, and distant metastases were associated with worse survival; surgical resection and administration of chemotherapy were associated with a reduced risk of death. Among non-metastatic patients treated with surgical resection, administration of chemotherapy was protective, while a positive lymph node ratio (LNR) ≥42% (median value) was associated with an increased risk of death. There was no difference in the number of examined lymph nodes between LNR cohorts.

CONCLUSIONS

Patients with rNECs experience dismal survival outcomes, including those with non-metastatic disease treated with curative-intent surgical resection. Neoadjuvant therapy can serve as a useful biologic test, and surgical resection should be judiciously employed.