Risk Factors for Predicting Lymph Node Metastasis in Submucosal Colorectal Cancer

Device-assisted endoscopic full-thickness resection in colorectum: Systematic review and meta-analysis

OBJECTIVES

Endoscopic full-thickness resection (EFTR) is emerging as an effective modality for mucosal and submucosal lesions in the colorectum. In this systematic review and meta-analysis, we aimed to analyze the success and safety of device-assisted EFTR in the colon and rectum.

METHODS

A literature search was performed in the Embase, PubMed, and Medline databases for studies evaluating device-assisted EFTR between inception to October 2022. The primary outcome of the study was clinical success (R0 resection) with EFTR. Secondary outcomes included technical success, procedure duration, and adverse events.

RESULTS

In all, 29 studies with 3467 patients (59% male patients, 3492 lesions) were included in the analysis. The lesions were located in right colon (47.5%), left colon (28.6%), and rectum (24.3%). EFTR was performed for subepithelial lesions in 7.2% patients. The pooled mean size of the lesions was 16.6 mm (95% confidence interval [CI] 14.9-18.2, I2 98%). Technical success was achieved in 87.1% (95% CI 85.1-88.9%, I2 39%) procedures. The pooled rate of en bloc resection was 88.1% (95% CI 86-90%, I2 47%) and R0 resection was 81.8% (95% CI 79-84.3%, I2 56%). In subepithelial lesions, the pooled rate of R0 resection was 94.3% (95% CI 89.7-96.9%, I2 0%). The pooled rate of adverse events was 11.9% (95% CI 10.2-13.9%, I2 43%) and major adverse events requiring surgery was 2.5% (95% CI 2.0-3.1%, I2 0%).

CONCLUSION

Device-assisted EFTR is a safe and effective treatment modality in cases with adenomatous and subepithelial colorectal lesions. Comparative studies are required with conventional resection techniques, including endoscopic mucosal resection and submucosal dissection.

Management after non-curative endoscopic resection of T1 rectal cancer

Since the introduction of population-based screening, increasing numbers of T1 rectal cancers are detected and removed by local endoscopic resection. Patients can be cured with endoscopic resection alone, but there is a possibility of residual tumor cells remaining after the initial resection. These can be located intraluminally at the resection site or extraluminally in the form of (lymph node) metastases. To decrease the risk of residual cells progressing towards more advanced disease, additional treatment is usually needed. However, with the currently available risk stratification models, it remains challenging to determine who should and should not be further treated after non-curative endoscopic resection. In this review, the different management strategies for patients with non-curatively treated T1 rectal cancers are discussed, along with the available evidence for each strategy and relevant considerations for clinical decision making. Furthermore, we provide practical guidance on the management and surveillance following non-curative endoscopic resection of T1 rectal cancer.

Precisional detection of lymph node metastasis using tFCM in colorectal cancer

The detection of colorectal cancer (CRC) lymph node (LN) metastases significantly influences treatment choices, yet identifying them in samples is time-consuming and error-prone. To enhance efficiency, we have established a LN metastasis detection method utilizing triple-parameter flow cytometry (tFCM) and have conducted a comparative assessment of its accuracy and cost-effectiveness in contrast to conventional pathological examinations. This technique utilized biomarkers cytokeratin 20 (CK20), epithelial cell adhesion molecules (EpCAM), and Pan-CK. tFCM's sensitivity was validated by analyzing known cell line concentrations (SW480 and SW620) in peripheral blood mononuclear cells (PBMCs), with CK20, EpCAM, and Pan-CK showing significant expression in CRC cell lines but not in PBMCs. A strong linear correlation was observed in the mixed leukocyte environment (R 2 = 0.9988). Subsequently, tFCM and pathological sections were employed to analyze LNs from CRC patients, enabling comparison of detection accuracy. Within the 36 LNs studied, tFCM successfully identified tumor cells with varying metastasis degrees, including micro-metastasis and isolated tumor cell clusters. Notably, relying solely on pathological sections led to a potential 25% misdiagnosis rate for LNs. In contrast, tFCM effectively minimized this risk. In summary, compared to traditional pathological sections, tFCM is a more advantageous method for detecting nodal metastasis in CRC patients, offering a more precise prognosis for these patients.