Transanal Endoscopic Microsurgery Implementation in Ultra-Low Anterior Resection

Abstract

Background:

Distal rectal cancer resection is an ongoing challenge for the colorectal surgeon. In recent years new technical approaches, especially with implementation of transanal platforms were developed to help in the visualization and resection of these tumors. Nevertheless, the use of these platforms is demanding with significant complications during the onset phase.

Methods:

Patients with very low rectal cancer were operated on in a single tertiary center with a combined abdominal and transanal endoscopic microsurgery (TEM) approach. Demographic, pathological, and surgical data were collected retrospectively with an emphasis on distal margin involvement.

Results:

Nineteen patients were operated on during the study period. All patients had negative distal resection margins with a low complication rate. The distant metastasis and local recurrence rates were low with a mean follow-up of 2 years.

Conclusions:

TEM provides an appealing and viable option for the resection of low rectal cancer in a combined transabdominal and transanal approach in patients with a good response after neoadjuvant treatment. This is one of the available platforms a colorectal surgeon might benefit from having in his armamentarium. It has a very low complication rate with maintenance of oncological principles, enabling a clear visualization of the distal rectum, and thus ensures free distal resection margins.

Introduction

The resection of low laying rectal cancer is very demanding with sphincter preservation being very much sought after, with a constant effort to reduce the end colostomy rate. There is an ongoing debate about the quality of life, especially in intersphincteric resections.¹ This endeavor needs to be balanced with an uncompromised oncological outcome. The surgeon faces a significant difficulty in low rectal malignancies. It is further enhanced in obese and male patients with a narrow pelvis.^2,3 The determination of a clear distal margin is challenging and demanding. In recent years several approaches were examined to facilitate this resection. The transanal approach with transanal total mesorectal excision (TA TME) in particular gained substantial popularity. The results of this technique are promising; however, one needs to bear in mind its steep learning curve and relatively high complication rate.^4–6 TEM is widely accepted in the treatment of benign and early malignant lesions throughout the rectum.⁷ It provides an excellent visualization with a very low complication rate.⁸ The use of TEM platform as an alternative platform for the TA TME procedure has not gained a wide popularity due to various reasons such as its relative complexity and high cost. We have tried to assess the utility of TEM for distal margin determination as part of a combined approach, in patients undergoing ultra-low anterior resection as part of a future endeavor to extend its implementation for a full transanal TME procedure.

Materials and Methods

A retrospective data collection was performed from the population of patients with rectal cancer who underwent low anterior resection in one tertiary center. All patients were operated on by a single surgeon in the years 2014–2017. Patients were selected for the procedure as deemed suitable by the operating surgeon with regard to tumor and patient characteristics. Tumors located in the lower rectum were selected for the procedure. Most of the selected tumors had a good clinical response for neoadjuvant therapy with a preference toward tumors lying in the posterior and lateral rectal walls.

All patients have undergone an ultra-low anterior resection with hand-sewn anastomosis in a combined transabdominal and TEM approach. The TEM system (Richard-Wolf, Germany) was used after completing the abdominal phase and reaching the level of the levator ani complex. The distal resection margin was marked above the dentate line with clear distance from the tumor, then entering the intersphincteric plane and completing circumferential resection, joining the abdominal part and extracting the specimen through the anus. This enables an excellent visualization of the rectum and the tumor, minimizing violation of anatomic planes, and maximizing sphincter preservation.

Pathology reports, patient demographics, and operative and postoperative data were collected.

Results

Nineteen patients were operated on in the combined approach. Except for one patient who was operated on after a local excision by TEM with worrisome pathological features, all patients received neoadjuvant chemo radiation before surgery. Fifteen of them were male. Patient characteristics are presented in Table 1. The average age was 60.26 and the length of stay (LOS) was 9. The average distance from the anal verge was 3.9 cm. Both the distal and circumferential margins were found to be free in all patients with six patients having complete pathological response harvest as shown in Table 2. The mean follow-up period was 2 years. One patient had local recurrence of the tumor and one patient presented with distant metastases. Two patients were converted to abdominoperineal resection due to a close, however, free distal resection margin of 1 and 2 mm, respectively, as decided in a multidisciplinary meeting. The complication rate was low and mostly mild (Table 3).

Table 1.

Patient Characteristics

Patient	Gender	Age	Tumor location (cm from AV)
1	Male	51	3
2	Male	70	3
3	Male	66	4
4	Male	70	5
5	Male	71	4
6	Female	67	3
7	Female	57	4
8	Male	59	2
9	Female	54	6
10	Male	62	3
11	Female	74	4
12	Male	67	3
13	Male	65	1
14	Male	47	3
15	Male	59	7
16	Male	40	6
17	Male	50	4
18	Male	68	4
19	Male	40	3

AV, anal verge.

Table 2.

Pathological Results

Patient	Distal margin (cm)	Radial margin (cm)	CPR
1	0.5	Positive	No
2	N/A	N/A	Yes
3	N/A	N/A	Yes
4	N/A	N/A	Yes
5	1.3	Negative	No
6	N/A	N/A	Yes
7	0.9	Negative	No
8	0.1	Negative	No
9	0.2	Negative	No
10	0.3	Negative	No
11	2.0	Negative	No
12	0.7	Negative	No
13	0.7	Negative	No
14	0.2	Negative	No
15	0.5	Negative	No
16	N/A	N/A	Yes
17	4.0	Negative	No
18	0.2	Negative	No
19	N/A	N/A	Yes

CPR, complete pathological response; N/A, not applicable.

Table 3.

Surgical Complications and Follow-up

Patient	Complication	LOS (days)	Follow-up (months)	Distal Mts	Local recurrence
1	SBO	8	12	No	Yes
2	No	5	6	No	No
3	No	7	10	No	No
4	No	7	10	No	No
5	No	6	10	No	No
6	No	7	7	No	No
7	No	7	5	No	No
8	No	7	3	No	Yes
9	No	5	30	No	No
10	No	7	33	Yes	No
11	SBO	21	29	No	No
12	No	6	28	No	No
13	Eventration	8	24	No	No
14	Intraabd abscess	8	22	No	No
15	SBO+wound infection	18	23	No	Yes
16	No	7	24	No	No
17	No	7	16	No	No
18	Bacteremia	23	34	No	No
19	No	5	2	No	No

LOS, length of stay; Mts, metastases; SBO, small bowel obstruction.

Discussion

The feasibility and safety of the TEM procedure was established in different studies,⁹ even in redo cases.¹⁰ Various transanal platforms have been tried to access in a more accurate manner the distal rectum, mainly completing the abdominal part of the operation, maintaining the goal of total mesorectal excision with negative distal resection margins. The TA TME platform which gained a rapid widespread lately is currently the most studied method. Major complications have been reported implementing this approach; especially during its initiation phase. The learning curve and training programs for the implementation of this technique need to be further determined.¹¹ Marking the distal margin in colonoscopy is problematic due to the technical difficulty of the endoscopic procedure in the distal rectum. It has also inherent inaccuracy as the ink markings tend to spread in the tissue, thus further complicating surgery by obliterating planes of dissection. There is no doubt that TEM is an expensive and demanding technique. Its major advantage is the three-dimensional (3D) vision that the system provides with a wide range of applicable clinical entities.¹² After acquiring the proper knowledge and experience through excision of benign and early malignant lesions one might move forward to other utilizations such as described herein. In our study, the surgeon who performed the procedures had a vast earlier experience with TEM, making its added utilization less challenging. We have demonstrated a low complication rate, comparable to standard anterior resection with a negligible rate of major events. The oncological results obtained were good, both in the short and longer follow-up period. In particular, distal margins were found free of tumor in all the resected specimens of the patients who presented with very low rectal cancers and underwent an ultra-low sphincter preserving surgery. We lack long-term results for the oncological outcome. Another drawback of our study was its retrospective design and that patient selection was not predetermined by fixed criteria, rather they were selected by the surgeon performing the surgery, during the operation (mainly in the male narrow pelvis).

We find the addition of TEM as being extremely helpful in the visualization and resection of very low rectal cancers after neoadjuvant treatment. The patient selection is crucial with residual small tumors to ensure technical feasibility. TEM provides a safe platform with an excellent vision, achieving free distal margins in all patients, thus providing an attractive adjunctive method for sphincter preservation with sound oncological principles. This platform is one of the available options in the tool box of a colorectal surgeon not compared thoroughly thus far with other devices such as the TA TME. Additional means of 3D visualization, such as 3D laparoscopy and robotics, carry a promise and will most surely be compared in the near future with the TEM counterpart.

TEM implementation in the resection of low rectal cancer in a combination with transabdominal approach carries a promise with further research needed to establish the correct patient selection and determine its role in transanal TME.

Footnotes

Disclosure Statement

No competing financial interests exist.

References

Klose

, Tarantino

, Kulu

, Bruckner

, Trefz

, Schmidt

, Schneider

, Hackert

, Büchler

, Ulrich

. Sphincter-preserving surgery for low rectal cancer: Do we overshoot the mark?. J Gastrointest Surg, 2017; 21:885–891.

Jung

, Yu

, Choi

, et al. Risk factors and oncologic impact of anastomotic leakage after rectal cancer surgery. Dis Colon Rectum, 2008; 51:902–908.

Targarona

, Balague

, Pernas

, et al. Can we predict immediate outcome after laparoscopic rectal surgery? Multivariate analysis of clinical, anatomic, and pathologic features after 3-dimensional reconstruction of the pelvic anatomy. Ann Surg, 2008; 247:642–649.

Veltcamp Helbach

, Deijen

, Velthuis

, et al. Transanal total mesorectal excision for rectal carcinoma: Short-term outcomes and experience after 80 cases. Surg Endosc, 2016; 30:464–470.

Atallah

, Martin-Perez

, Albert

, et al. Transanal minimally invasive surgery for total mesorectal excision (TAMIS-TME): Results and experience with the first 20 patients undergoing curative-intent rectal cancer surgery at a single institution. Tech Coloproctol, 2014; 18:473–480.

Tuech

, Karoui

, Lelong

, et al. A step toward NOTES total mesorectal excision for rectal cancer: Endoscopic transanal proctectomy. Ann Surg, 2015; 261:228–233.

de Graaf

, Doornebosch

, Tetteroo

, et al. Transanal endoscopic microsurgery is feasible for adenomas throughout the entire rectum: A prospective study. Dis Colon Rectum, 2009; 52:1107–1113.

Guerrieri

, Baldarelli

, de Sanctis

, et al. Treatment of rectal adenomas by transanal endoscopic microsurgery: 15 years' experience. Surg Endosc, 2010; 24:445–449.

Allaix

, Rebecchi

, Giaccone

, et al. Long-term functional results and quality of life after transanal endoscopic microsurgery. Br J Surg, 2011; 98:1635–1643.

10.

Khoury

, Gilshtein

, Nordkin

, Kluger

, Duek

S-D

. Repeated transanal endoscopic microsurgery is feasible and safe. J Laparoendoscopic Adv Surg Tech A, 2013; 23:216–219.

11.

Penna

, Buchs

, Bloemendaal

, Hompes

. Transanal total mesorectal excision for rectal cancer: The journey towards a new technique and its current status. Expert Rev Anticancer Ther, 2016; 16:1145–1153.

12.

Gilshtein

, Duek

, Khoury

. Transanal endoscopic microsurgery: Current and future perspectives. Surg Laparosc Endosc Percutan Tech, 2016; 26:e46–e49.