A case of local recurrence following transanal total mesorectal excision: a new form of port-site metastasis?

Long-term oncological outcomes of transanal versus laparoscopic total mesorectal excision for mid-low rectal cancer: a retrospective analysis of 2502 patients

BACKGROUND

Transanal total mesorectal resection (taTME) has recently emerged as a promising surgical approach for the treatment of mid-low rectal cancer. However, there is limited evidence on the long-term survival outcomes associated with taTME. This retrospective study aimed to compare the overall survival (OS), disease-free survival (DFS), and cancer-specific survival of taTME and laparoscopic TME (laTME) in patients with mid-low rectal cancer.

MATERIALS AND METHODS

From July 2014 to June 2022, a total of 3627 patients were identified from two prospective cohorts: the laparoscopic rectal surgery cohort and the CNTAES cohort. To balance the baseline characteristics between the taTME and laTME groups, propensity score matching (PSM) was performed.

RESULTS

A total of 2502 patients were included in the study. Prior to PSM, the laTME group comprised 1853 patients, while the taTME group comprised 649 patients. The 5-year OS (82.9% vs. 80.4%, P =0.202) and 5-year DFS (74.4% vs. 72.5%, P =0.167) were comparable between the taTME and laTME groups. After PSM, the taTME group showed no statistically significant difference in the 5-year OS (83.1% vs. 79.2%, P =0.101) and 5-year DFS (74.8% vs. 72.1%, P =0.135) compared to the laTME group. Subgroup analysis further suggested that taTME may potentially reduce the risk of death [hazard ratio 0.652; (95% CI, 0.452-0.939)] and disease recurrence [hazard ratio 0.736; (95% CI, 0.562-0.965)] specifically in patients with low rectal cancer.

CONCLUSION

In this study, taTME demonstrated comparable oncologic safety to laTME in patients with mid-low rectal cancer. Moreover, the results indicate that taTME may confer potential survival benefits for patients with low rectal cancer.

The role of transanal total mesorectal excision

At inception, transanal total mesorectal excision (TaTME) was hypothesized to be a solution for several problems encountered in pelvic surgery, particularly for distal rectal cancer. The transanal part of the procedure is less hampered by patient related factors such as visceral obesity and a narrow bony pelvis and can thus overcome access and visualization problems encountered with a pure abdominal approach. Clearly, as for any new technique, a learning curve needs to be negotiated, ideally without unacceptable harm to patients. Once in experienced hands, TaTME might overcome challenges found in anatomically challenging rectal cancer patients as well as for other indications. The role of TaTME is not to replace, but rather complement its abdominal counterpart.

Local Recurrence After Transanal Total Mesorectal Excision for Rectal Cancer: A Multicenter Cohort Study

OBJECTIVE

This study aimed to determine local recurrence (LR) rate and pattern after transanal total mesorectal excision (TaTME) for rectal cancer.

BACKGROUND

TaTME for mid- and low rectal cancer has known a rapid and worldwide adoption. Recently, concerns have been raised on the oncological safety in light of reported high LR rates with a multifocal pattern.

METHODS

This was a multicenter observational cohort study in 6 tertiary referral centers. All consecutive TaTME cases for primary rectal adenocarcinoma from the first TaTME case in every center until December 2018 were included for analysis. Patients with benign tumors, malignancies other than adenocarcinoma and recurrent rectal cancer, as well as exenterative procedures, were excluded. The primary endpoint was 2-year LR rate. Secondary endpoints included patterns and treatment of LR and histopathological characteristics of the primary surgery.

RESULTS

A total of 767 patients were identified and eligible for analysis. Resection margins were involved in 8% and optimal pathological outcome (clear margins, (nearly) complete specimen, no perforation) was achieved in 86% of patients. After a median follow-up of 25.5 months, 24 patients developed LR, with an actuarial cumulative 2-year LR rate of 3% (95% CI 2-5). In none of the patients, a multifocal pattern of LR was observed. Thirteen patients had isolated LR (without systemic disease) and 10/13 could be managed by salvage surgery of whom 8 were disease-free at the end of follow-up.

CONCLUSIONS AND RELEVANCE

This study shows good loco regional control after TaTME in selected cases from tertiary referral centers and does not indicate an inherent oncological risk of the surgical technique.

Transanal total mesorectal excision: the Slagelse experience 2013-2019

OBJECTIVE

To describe outcomes after transanal total mesorectal excision (TaTME) 5 years from implementation at a large-volume colorectal unit, including local recurrence, distant metastasis, and survival.

BACKGROUND

Transanal total mesorectal excision (TaTME) is a relatively new procedure for mid- and low-rectal cancer, with well-documented safety and feasibility. However, data on long-term results are limited.

METHODS

This study was based on a prospective data collection via a maintained database in a large colorectal unit. The database included patients who underwent TaTME from December 2013 through July 2019. We have updated the database through a review of patient charts, including radiology and pathology reports. Data collection included operative details, intraoperative findings, postoperative complications, pathologic results, and oncologic results.

RESULTS

During the study period, two hundred patients underwent TaTME in the study period (men = 147). The mean BMI was 26.7%, and the mean tumor height from the anal verge was 7.86 cm. Neoadjuvant treatment was given to 22% of patients. Anastomotic leakage occurred in 9.3% of patients, and the overall rate of postoperative complications was 24.5%. The TME specimen was incomplete in 11% of patients, and the CRM was positive in 5.5% of patients. Local recurrence (LR) occurred in seven patients with a follow-up of at least 2 years (4.7%). Distant metastasis (DM) occurred in 12% of patients. The overall survival was 90% and disease-free survival was 81%. The operating time was reduced in the later period of our experience.

CONCLUSIONS

This study showed that TaTME is feasible, safe, and had acceptable short-term outcomes and an acceptable rate of LR. The study included, however, one group that was non-randomized, and the follow-up was not long enough for most patients. Studies with longer follow-up data are awaited.

Long-term oncological results after transanal total mesorectal excision for rectal carcinoma

Background

Transanal total mesorectal excision (TaTME) for mid and low rectal cancer has been shown to improve short-term outcomes, mostly due to lower conversion rates and with improved quality of the specimen. However, robust long-term oncological data supporting the encouraging clinical and pathological outcomes are lacking.

Methods

All consecutive patients undergoing TaTME with curative intent for mid or low rectal cancer in two referral centers in The Netherlands between January 2012 and April 2016 with a complete and minimum follow-up of 36 months were included. The primary outcome was local recurrence rate. Secondary outcomes were disease-free survival, overall survival and development of metastasis.

Results

There were 159 consecutive patients. Their mean age was 66.9 (10.2) years and 66.7% of all patients were men. Pathological analysis showed a complete mesorectum in 139 patients (87.4%), nearly complete in 16 (10.1%) and an incomplete mesorectum in 4 (2.5%). There was involvement of the CRM (< 1 mm) in one patient (0.6%) and no patients had involvement of the distal margin (< 5 mm). Final postoperative staging after neoadjuvant therapy was stage 0 in 11 patients (6.9%), stage I in 73 (45.9%), stage II in 31 (19.5%), stage III in 37 (23.3%) and stage IV in 7 (4.4%). The 3-year local recurrence rate was 2.0% and the 5-year local recurrence rate was 4.0%. Median time to local recurrence was 19.2 months. Distant metastases were found in 22 (13.8%) patients and were diagnosed after a median of 6.9 months (range 1.1–50.4) months. Disease-free survival was 92% at 3 years and 81% at 5 years. Overall survival was 83.6% at 3 years and 77.3% at 5 years.

Conclusions

The long-term follow-up of the current cohort confirms the oncological safety and feasibility of TaTME in two high volume referral centers for rectal carcinoma. However, further robust and audited data must confirm current findings before widespread implementation of TaTME.

Transanal TME: new standard or fad?

Transanal total mesorectal excision (taTME) has been developed to overcome the difficulty of laparoscopic dissection and transection in the deep pelvis. TaTME has several clinical benefits over laparoscopic surgery, such as better exposure of the distal rectum and direct determination of distal resection margin. Although evidence demonstrating the true benefits of taTME over laparoscopic TME (LapTME) is still insufficient, accumulating data have revealed that, as compared with LapTME, taTME is associated with shorter operative time and a lower conversion rate without jeopardizing other short-term outcomes. However, taTME is a technically demanding procedure with specific complications such as urethral injury, and so sufficient experience of LapTME and step-by-step acquisition of the skills needed for this procedure are requisite. The role of transanal endoscopic surgery is expected to change, along with the recent progress in the treatment of rectal cancer, such as robotic surgery and the watch-and-wait strategy. Optimization of treatment will be needed in the future in terms not only of oncological but also of functional outcomes.