Robotic abdominal resection of tailgut cysts – A technical note with step‐by‐step description

Abstract Aim Here, we describe a step‐by‐step standardized technique for tailgut cyst resection using a single‐docking robotic approach. Method Each step of the technique is illustrated using a composite collection of four operative patient videos to demonstrate the advantages and feasibility of this technique. The robot platform utilised is Da Vinci Xi. Results Five female patients have undergone this operation in our unit. The size of tumours ranged from 12 to 45 mm. Median operating time was 100 min (range 90–150). Mean blood loss in all the patients was less than 50 ml. There were no major intraoperative complications. One patient had a postoperative presacral collection which required radiological drainage. Length of stay in all patients was one day. Conclusions This technique using a single‐docking robotic approach appears safe and feasible. The robotic approach results in improved dexterity and more accurate dissection, better retraction and excellent vision which improves the ease of operating in the pelvis. Therefore, this approach can be replicated for use in a wide variety of patients with tailgut cysts.


ME THOD
We present our case series of five patients who underwent robotic abdominal resection of a tailgut cyst via the anterior approach with a step-by-step video showing the technique using the da Vinci Xi ® surgical system [7]. Patient data was collected prospectively between June 2020 and February 2021.

Patient positioning
The patient is placed in modified Lloyd Davies position.

Port placement
The anatomical landmarks -pubic symphysis, xiphoid process, costal margins and anterior-superior iliac spines are identified. A line is drawn between the pubic symphysis and xiphoid process. Midclavicular lines are drawn at a distance of 6-8 cm from midline.
A curved line between the umbilicus and both iliac spines is created which demarcates the line at which the trocars will be placed.
Pneumoperitoneum is formed using a Veress needle at Palmer's point and achieved with carbon dioxide insufflation at pressures

Surgical steps
The patient is placed in Trendelenburg position with a right-side tilt and manual displacement of small bowel and greater omentum towards the upper abdomen is performed.

Docking
The robot is positioned on the left side of the patient at a 90° angle.
The robot arms are aligned with the trocars and targeting performed.
Robotic instruments are introduced under direct vision.

Lateral mobilization of the rectum
The tip up grasper in R1 is used to retract the sigmoid colon cranially

Pelvic dissection
Once the tumour is identified, care must be taken when separating the tumour from the posterior rectum to avoid damage or perforation. Dissection is carefully performed whilst maintaining adequate traction when mobilising the cyst to avoid tumour perforation. After the cyst is fully mobilised, washout of the surgical bed is performed and haemostasis confirmed. The specimen is extracted via a bag through a small Pfannenstiel incision, and the trocars are removed under direct vision.

COMPARISON WITH OTHER ME THODS , ADVANTAG E S , AND DISADVANTAG E S
Other surgical approaches described in the literature include the anterior, posterior, or combined approach depending on the size and location of the tumour [4]. The combined approach is preferred when there is nerve involvement as it allows for improved visualization of ureters, vessels, pelvic nerves, and rectum in the anterior approach and good exposure of the nerve roots provided by the posterior approach [8,9]. However, the posterior approach is also associated with a risk of injury to lateral pelvic nerves or haemorrhage [10]. A posterior approach is more commonly used for lesions distal to S3, and most patients require resection of the coccyx, which can prolong the length of stay and cause chronic pain. Different minimally invasive approaches have been described including laparoscopic, robotic and transanal minimally invasive surgery (TAMIS). TAMIS is associated with a higher risk of pelvic infection [11]. Laparoscopic or robotic surgery with anterior approach allows for enhanced visualization of pelvic structures and precise dissection. Robotic surgery specifically provides three-dimensional views, superior dexterity with multiarticulated instruments and good retraction [5]. Tumours located close to levator ani and coccygeal muscles are easily accessible and if there is an injury to the surrounding organs, repair is often much easier with this approach [12].

RE SULTS
We describe data from five female patients. Their symptoms ranged from abdominal pain or proctalgia to asymptomatic patients with incidental findings. Demographic and operative details of the patients are listed in Table 1. There were no major complications. Histology in all the patients confirmed retrorectal cystic hamartomas. An intraoperative air-leak test was performed in all cases and no rectal injuries were detected. Mean length of stay was one day.
The postoperative discomfort of the patients was minimal in two patients, two patients had no postoperative pain, and one patient reported the same preoperative discomfort (Table 2). One patient was diagnosed with presacral collection a month after surgery, which required radiology guided drainage.

CON CLUS ION
This technique seems safe and feasible and might be adopted as an alternative when the surgeon is experienced in minimally invasive surgery especially if the cysts are located above the levator muscles.
Studies with larger samples are necessary to confirm the outcomes of this technique against other surgical approaches.

ACK N OWLED G EM ENT
Open Access Funding provided by Universita degli Studi della Campania Luigi Vanvitelli within the CRUI-CARE Agreement.
[Correction added on 23 May 2022, after first online publication: Open access Funding statement has been added.]

CO N FLI C T O F I NTE R E S T
The authors declare that they have no conflict of interests.

E TH I C A L A PPROVA L
All patients gave written informed consent before undergoing the procedure and for recording and publication. This study was performed in compliance with the Declaration of Helsinki.

DATA AVA I L A B I L I T Y S TAT E M E N T
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.