Transanal division of the anorectal junction followed by laparoscopic low anterior resection and coloanal pouch anastomosis: A technique facilitated by a balloon port.

We performed a laparoscopic ultra low anterior resection in two patients with low rectal cancers (3 cm from dentate line). A transanal division and continuous suture closure of anorectal junction was performed first followed by laparoscopic low anterior resection. A handsewn anastomosis between colonic pouch/transverse coloplasty and anal canal was facilitated by use of a transanal balloon port.

INTRODUCTION

Laparoscopic low anterior resection in patients with low rectal cancers is restricted by the inability to staple low down in the pelvis. The space is limited, the firing angle is too acute to produce a right-angled staple line. Moreover, the surgeon lacks the tactile feedback to ensure adequate distal clearance. We present a technique to ensure adequate distal resection margin while performing a sphincter saving ultra low rectal resection with coloanal anastomosis.

TECHNIQUE

The operation begins with the perineal first approach.

Transanal division of anorectal junction using lone star retractor

Cytocidal washout of rectum is followed by suturing a swab between the tumour and the intended site of incision. After infiltration with saline adrenaline, a circumferential incision is performed 1.5 cm from the dentate line and deepened posteriorly until fat is identified [Figure 1]. The dissection is completed circumferentially [Figure 2]. Once the rectum is transected, the proximal rectum is closed with continuous vicryl sutures (ends kept long) to prevent spillage during abdominal dissection. A 4x4 swab and Tegaderm dressing are applied to the surface to maintain pneumoperitoneum.

Figure 1

Circumferential incision 1.5 cm from the dentate line

Figure 2

The dissection is completed circumferentially

Laparoscopic low anterior resection

A standard medial to lateral dissection is performed, including mobilisation of the splenic flexure and full rectal mobilisation [Figure 3]. During dissection, the ends of previously sutured rectal stump are identified and freed. Through a 5-cm suprapubic incision, the colon and rectum are delivered and transected at the descending-sigmoid junction. The descending colon is used to construct a 6-cm J-pouch [Figure 4]. A coloplasty may be more appropriate for the narrow male pelvis [Figure 5]. The pouch is closed with interrupted sutures to prevent contamination, and stay stitches are placed at both corners as markers. The pouch is returned into the abdomen and the terminal ileum is marked to perform a loop ileostomy at the end of the procedure.

Figure 3

The lower rectum is dissected from the prostate

Figure 4

6-cm colonic J-pouch

Figure 5

8-cm coloplasty

Coloanal pouch anastomosis

To maintain pneumoperitoneum and aid mobilisation of the pouch into the anal canal, a transanal balloon port is used [Figure 6]. The previously placed stay stitches on the pouch are identified and a grasper from the balloon port is used to pull the pouch into the anal canal [Figure 7]. The pouch has to be tension free [Figure 8]. The inferior end of the pouch is reopened by removing the interrupted suture [Figure 9]. An interrupted hand-sewn anastomosis is performed [Figure 10].

Figure 6

Transanal balloon port sitting against the Levator anii

Figure 7

Grasper from the balloon port is used to pull the pouch into the anal canal

Figure 8

Tension-free pouch

Figure 9

The inferior end of the pouch is reopened by removing the interrupted suture

Figure 10

Coloanal anastmosis 1.5 cm from the dentate line

RESULTS

Case 1

A 79 year lady was diagnosed with a malignant polyp in the anterior rectal wall 3 cm from the dentate line (MRI staging T1N0, CT scan; no distant metastasis). She underwent a laparoscopic ultra low anterior resection. Postoperative course was uneventful and the patient was discharged home on day 4. Histology revealed T1 N1 tumour (2/14 lymph nodes involved). The distal resection margin was 1 cm and the circumferential margin was 1.7 cm.

Case 2

An 82-year-old male presented with early rectal cancer in the posterior wall 3 cm from the dentate line (MRI staging T1/T2 N0, CT scan; no distant metastasis). He underwent surgery and was discharged home on day 7. Histology revealed T2 N0 cancer (0/18 nodes involved). The distal resection margin was 1.5 cm and the circumferential margin was 8 mm.

Both patients had clinically good sphincter function before surgery and were discussed in the multidisciplinary meeting.

DISCUSSION

Open low anterior resection with handsewn coloanal anastomosis is an established sphincter-saving procedure for management of ultra low rectal cancer. Sweeney JL 1989, from St Marks Hospital London, presented longterm results of such operations performed on 84 patients with no disadvantage in potential cure with acceptable functional results.[1] Variations in hybrid technique of laparoscopic low anterior resection and hand-sewn anastomosis have been described.[23]

The currently available laparoscopic staplers are restricted by their inability to crossstaple the rectum at right angle (maximum 60°) leading to oblique transection with incomplete excision on one side of the rectum and more damage to the sphincters on the other side. The perineal first approach ensures an adequate distal transverse transection. Also, division of the anorectal junction first has an added advantage of facilitating cephalad retraction and dissection of the lower rectum during the laparoscopic dissection. The distinct advantage of this technique may be seen more in a male patient with a narrow pelvis.

A Lone star retractor (author's preference) or purse string suture anoscope can be used for anal retraction; however, we are aware of the rare instances of cutaneous perianal recurrence on the site of Lone star retractor after Jpouch coloanal anastomosis for rectal cancers.[4]

In all sphincter saving procedures, whether a stapled low anterior resection, sutured coloanal anastomosis, TEM or our approach, there is a small risk of tumour dissemination. The risks and benefits were discussed with our patients and they preferred this sphincter-saving approach. Although evidence regarding rectal washout with cytocidal solution to prevent tumour implantation is lacking, most surgeons in the UK would routinely perform it.[56] In this technique we performed the following steps to prevent implanatation of malignant cells:

Cytocidal washout was performed before starting the procedure.

A swab was sutured between the tumour and the intended line of transanal transection.

After complete transection of the anorectal junction, the divided end of rectum was closed with a continuous suture.

TEMS procedure is an alternative management; however, the risk of lymph node metastasis/local recurrence cannot be underestimated. Nash et al., found a high rate of local recurrence (11.3%) after TEMS for T1 cancers from well-known centres.[7] In the first case, 1/14 lymph nodes was involved in spite of being a T1 cancer. This patient would likely develop nodal recurrence if TEMS had been performed.

We limit TEMS to elderly unfit patients or those refusing radical surgery. Both patients were fit despite being elderly and after full counselling they opted for this approach rather than TEMS or an abdomino-perineal resection.

For oncological clearance and because the intended site of incision is 1.5 cm from dentate line, we transect the anorectal junction rather than perform mucosectomy or intersphincteric dissection as for inflammatory bowel disease. This technique preserves the anal transition zone and an integral part of the musculature of the anal canal, in an attempt to achieve a better functional outcome.

A coloanal pouch/coloplasty has been shown to improve the quality of life and bowel function for the first 1 year compared to straight anastomosis, especially in elderly patients with a compromised anus.[8] We created a colonic J-pouch for the female patient and a transverse coloplasty pouch, for the male patient with narrow pelvis.

Specimen delivery via the anal canal is controversial. Bretagnol et al. found that transanal extraction of the specimen was associated with significant morbidity but there was no difference in either morbidity or functional outcome seen by Prete et al., in their comparison of two cohorts who had either transanal extraction or minilaparotomy.[39] We avoid transanal delivery of specimen to prevent sphincter injury or stretch from traction on bulky mesorectum. This also avoids using the sigmoid for pouch creation, which has been associated with more anastomotic leaks and inferior function.[10]

Delivering the pouch through the disconnected anal canal would lead to loss of the pneumoperitoneum. This was avoided by using a transanal balloon port. A grasper through the balloon port was used to deliver the pouch using the previously placed stay sutures. This technique would ensure delivery of the pouch under vision avoiding any twist or unnecessary traction.

Excellent long-term oncological outcome of such sphincter preserving surgery in low rectal cancers has been shown by Marks et al., 2010 with local recurrence rates of 2.5% over 34 months.[2]

CONCLUSIONS

This technique can be used for sphincter salvage while performing an ultra low laparoscopic anterior resection.