Transanal Endoscopic Microsurgery (TEM) for Rectal Cancer: University Hospital of North Tees Experience

Efficacy and safety of transanal endoscopic microsurgery for early rectal cancer: a meta-analysis

Background

The gold standard for the treatment of rectal cancer is radical surgery with total mesorectal excision (TME). As one of the alternatives to radical surgery, local resection has been proposed for the treatment of early rectal cancer. The purpose of this article was to evaluate the safety and efficacy of transanal endoscopic microsurgery (TEM) in the treatment of early rectal cancer.

Methods

By searching the PubMed, Cochrane Library, Web of Science, and China National Knowledge Infrastructure databases, we selected all articles on TEM for early rectal cancer. Two researchers independently completed the entire process from screening, inclusion to data extraction and performed statistical analysis using RevMan 5.3. The primary outcomes included basic patient characteristics, overall survival rate, disease-free survival rate, disease-specific survival rate, recurrence rate, and complication rate and type.

Results

A total of 33 articles were included in this meta-analysis. The results showed that the overall survival rate was 100% for T0 stage, 98.1% for Tis (carcinoma in situ) stage, and 80.2% for early stage rectal cancer patients (83.9% for T1 and 72.4% for T2). The weighted overall survival rate was 94% (RD = 0.94, 95% CI = 0.93-0.95, I 2 = 80%, P < 0.00001) for all stage patients, the weighted disease-free survival rate was 91% (RD = 0.91, 95% CI = 0.90-0.93, I 2 = 83%, P < 0.00001), and the disease-specific survival rate was 97% (RD = 0.97, 95% CI = 0.96-0.98, I 2 = 63%, P < 0.00001). The recurrence rate was 0.5% for T0 stage, 1.9% for Tis stage, and 11.9% for early stage rectal cancer patients (8.1% for T1 and 19.7% for T2). The weighted recurrence rate was 7% (RD = 0.07, 95% CI = 0.06-0.08, I 2 = 69%, P < 0.00001) for all stage patients. The weighted complications rate was 11% (RD = 0.11, 95% CI = 0.10-0.12, I 2 = 66%, P < 0.00001) for all stage patients, with Clavien-Dindo grade I accounting for 77.7%, Clavien-Dindo grade II accounting for 8%, and Clavien-Dindo grade III accounting for 14.3%.

Conclusion

The results showed that TEM has a high postoperative survival rate, low recurrence rate, and low complication rate in the T0 stage, Tis stage, and T1 stage, indicating its good safety and efficacy. For the treatment of T2 stage, TEM has a lower overall survival rate and a higher recurrence rate. Our meta-analysis results suggest that TEM alone is not recommended as a curative treatment for T2 stage; on the contrary, TME is more frequently recommended.

Risk of recurrence after local resection of T1 rectal cancer: a meta-analysis with meta-regression

BACKGROUND

T1 rectal cancer (RC) patients are increasingly being treated by local resection alone but uniform surveillance strategies thereafter are lacking. To determine whether different local resection techniques influence the risk of recurrence and cancer-related mortality, a meta-analysis was performed.

METHODS

A systematic search was conducted for T1RC patients treated with local surgical resection. The primary outcome was the risk of RC recurrence and RC-related mortality. Pooled estimates were calculated using mixed-effect logistic regression. We also systematically searched and evaluated endoscopically treated T1RC patients in a similar manner.

RESULTS

In 2585 unique T1RC patients (86 studies) undergoing local surgical resection, the overall pooled cumulative incidence of recurrence was 9.1% (302 events, 95% CI 7.3-11.4%; I2 = 68.3%). In meta-regression, the recurrence risk was associated with histological risk status (p < 0.005; low-risk 6.6%, 95% CI 4.4-9.7% vs. high-risk 28.2%, 95% CI 19-39.7%) and local surgical resection technique (p < 0.005; TEM/TAMIS 7.7%, 95% CI 5.3-11.0% vs. other local surgical excisions 10.8%, 95% CI 6.7-16.8%). In 641 unique T1RC patients treated with flexible endoscopic excision (16 studies), the risk of recurrence (7.7%, 95% CI 5.2-11.2%), cancer-related mortality (2.3%, 95% CI 1.1-4.9), and cancer-related mortality among patients with recurrence (30.0%, 95% CI 14.7-49.4%) were comparable to outcomes after TEM/TAMIS (risk of recurrence 7.7%, 95% CI 5.3-11.0%, cancer-related mortality 2.8%, 95% CI 1.2-6.2% and among patients with recurrence 35.6%, 95% CI 21.9-51.2%).

CONCLUSIONS

Patients with T1 rectal cancer may have a significantly lower recurrence risk after TEM/TAMIS compared to other local surgical resection techniques. After TEM/TAMIS and endoscopic resection the recurrence risk, cancer-related mortality and cancer-related mortality among patients with recurrence were comparable. Recurrence was mainly dependent on histological risk status.

The impact of transanal local excision of early rectal cancer on completion rectal resection without neoadjuvant chemoradiotherapy: a systematic review

BACKGROUND

The impact of transanal local excision (TAE) of early rectal cancer (ERC) on subsequent completion rectal resection (CRR) for unfavorable histology or margin involvement is unclear. The aim of this study was to provide a comprehensive review of the literature on the impact of TAE on CRR in patients without neoadjuvant chemoradiotherapy (CRT).

METHODS

We performed a systematic review of the literature up to March 2020. Medline and Cochrane libraries were searched for studies reporting outcomes of CRR after TAE for ERC. We excluded patients who had neoadjuvant CRT and endoscopic local excision. Surgical, functional, pathological and oncological outcomes were assessed. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed.

RESULTS

Sixteen studies involving 353 patients were included. Pathology following TAE was as follows T0 = 2 (0.5%); T1 = 154 (44.7%); T2 = 142 (41.2%); T3 = 43 (12.5%); Tx = 3 (0.8%); T not reported = 9. Fifty-three percent were > T1. Abdominoperineal resection (APR) was performed in 80 (23.2%) patients. Postoperative major morbidity and mortality occurred in 22 (11.4%) and 3 (1.1%), patients, respectively. An incomplete mesorectal fascia resulting in defects of the mesorectum was reported in 30 (24.6%) cases. Thirteen (12%) patients developed recurrence: 8 (3.1%) local, 19 (7.3%) distant, 4 (1.5%) local and distant. The 5-year cancer-specific survival was 92%. Only 1 study assessed anal function reporting no continence disorders in 11 patients. In the meta-analysis, CRR after TAE showed an increased APR rate (OR 5.25; 95% CI 1.27-21.8; p 0.020) and incomplete mesorectum rate (OR 3.48; 95% CI 1.32-9.19; p 0.010) compared to primary total mesorectal excision (TME). Two case matched studies reported no difference in recurrence rate and disease free survival respectively.

CONCLUSIONS

The data are incomplete and of low quality. There was a tendency towards an increased risk of APR and poor specimen quality. It is necessary to improve the accuracy of preoperative staging of malignant rectal tumors in patients scheduled for TAE.