Transanal minimally invasive surgery for rectal neuroendocrine tumors

Endoscopic therapy versus surgical resection for elderly patients with colorectal neuroendocrine tumors

BACKGROUND

Endoscopic therapy (ET) and surgical resection (SR) are common surgical methods for the treatment of colorectal neuroendocrine tumors (CRNETs). However, for elderly patients, it remains unclear which surgical method yields better long-term outcomes.

METHODS

Elderly patients ≥ 65 years with CRNETs diagnosed from 2000 to 2020 were identified from the Surveillance, Epidemiology, and End Results database. Propensity score matching (PSM) was used to minimize selection bias. The Kaplan-Meier method and Cox proportional hazards models were utilized to evaluate the effects of diverse demographic and clinical factors on overall survival (OS) and cancer-specific survival (CSS).

RESULTS

A total of 2214 patients were included in the study, with 1417 patients in the ET group and 797 patients in the SR group. After PSM, the ET group outperformed the SR group in terms of OS (hazard ratio [HR] 0.56, 95% confidence interval [CI] 0.44-0.70) and CSS (HR 0.21, 95% CI 0.11-0.40). Similarly, the ET group maintained its advantage in mean 1-, 3-, and 5-year OS and CSS rates compared to the SR group (P < 0.001). Multivariate Cox regression analysis identified age, sex, grade, marital status, and treatment modality as independent risk factors affecting OS, while age, sex, marital status, and treatment modality were identified as independent risk factors affecting CSS.

CONCLUSIONS

ET offered superior long-term outcomes for elderly patients ≥ 65 years with CRNETs.

European Neuroendocrine Tumor Society (ENETS) 2023 guidance paper for colorectal neuroendocrine tumours

This ENETS guidance paper, developed by a multidisciplinary working group, provides an update on the previous colorectal guidance paper in a different format. Guided by key clinical questions practical advice on the diagnosis and management of neuroendocrine tumours (NET) of the caecum, colon, and rectum is provided. Although covered in one guidance paper colorectal NET comprises a heterogeneous group of neoplasms. The most common rectal NET are often small G1 tumours that can be treated by adequate endoscopic resection techniques. Evidence from prospective clinical trials on the treatment of metastatic colorectal NET is limited and discussion of patients in experienced multidisciplinary tumour boards strongly recommended. Neuroendocrine carcinomas (NEC) and mixed neuroendocrine non-neuroendocrine neoplasms (MiNEN) are discussed in a separate guidance paper.

Long-term outcomes of transanal endoscopic microsurgery for the treatment of rectal neuroendocrine tumors

Background

Transanal endoscopic microsurgery (TEM) has been accepted worldwide for the treatment of local rectal lesions. We aimed to assess the efficacy and safety of TEM in the treatment of rectal neuroendocrine tumors (RNET).

Methods

A retrospective study of patients who had undergone TEM for RNET at our institution between December 2006 and June 2019 was performed. Demographic and tumor characteristics, operative and pathological details, complications, anal function questionnaires, and follow-up data were included.

Results

A total of 144 patients was included. TEM was performed as primary excision in 54 patients, after endoscopic forceps biopsy in 57 patients, and after incomplete resection by endoscopic excision in 33 patients. The median size of all primary tumors was 0.6 cm (range, 0.3–2.0 cm), and the negative resection margin was achieved in 142 (98.6%) patients. Postoperative complications (referring to only bleeding) occurred in 3 (2.1%) patients and was successfully managed with conservative method. After a median follow-up of 75.5 months after surgery, 3 patients died of other causes, and 2 patients suffered metastasis. An anal function questionnaire was posted 24 months after TEM. Among the results, 3 (2.1%) patients complained of major low anterior resection syndrome (LARS), including 1 (0.7%) who suffered from complete incontinence, while 6 (4.2%) patients had minor LARS.

Conclusions

TEM has satisfying long-term outcomes and relatively low anal function disturbance as for the treatment of small RNET. TEM also acts as a preferred salvage treatment for incomplete endoscopic excision.