Transanal endoscopic microsurgical platform for natural orifice surgery

[Transanal resection using a single port trocar: a new approach to NOTES]

INTRODUCTION

The morbidity and mortality, along with the functional changes that arise from radical surgery of rectal cancer, has led to an increasing interest in local treatment in the early stages of cancer of the rectum. Conventional transanal surgery has a high recurrence rate, for this reason transanal endoscopic microsurgery (TEM) is considered the treatment of choice in the last few years in large rectal adenomas and in early rectal cancer (low risk T1).

PATIENTS AND METHOD

We have intervened five patients, four with a diagnosis of villous adenoma of the rectum, and one in situ rectal carcinoma, using this new transanal approach, with a single port device.

RESULTS

The locations of the lesions were in the mid-rectum, at a mean distance of 9 cm (range 6-10) from the anal margin. All of them were situated in the posterior side. The resection margins were negative in all cases. The mean size of the adenomas was 4 cm, three being sessile shaped, and one with a short, thick pedicle (>1cm); the size of the carcinoma was 3 cm. The mean surgical time was 55 minutes. All the patients were discharged 48 hours after the surgical procedure.

CONCLUSION

We believe that the transanal endoscopic approach with a single port device is a simple, easily reproducible and cost-effective procedure when compared to TEM.

Transanal minimally invasive surgery: a giant leap forward

BACKGROUND

Our novel approach is a hybrid between transanal endoscopic microsurgery (TEM) and single-port laparoscopy that we have termed TransAnal Minimally Invasive Surgery (TAMIS). We report the clinical application of this technique and present preliminary data that show TAMIS to be an effective tool for resection of both malignant and benign lesions of the rectum.

METHODS

Over a 3-month period (May-July 2009) all patients with rectal lesions who were candidates for conventional transanal excision were offered the option to undergo TAMIS resection. Patients with biopsy-proven malignant lesions were required to undergo endorectal ultrasound preoperatively to determine tumor stage. To perform TAMIS, a single-incision laparoscopic surgery port (SILS Port, Covidien) is introduced into the anal canal by applying steady manual pressure. Once seated in position, endoscopic access to the rectal vault is gained and pneumorectum is established. With this access, ordinary laparoscopic instruments, including graspers, thermal energy devices, and needle drives, are used to perform the transanal excisions.

RESULTS

Six patients, aged 43-85 years old (mean = 59.8), underwent TAMIS resection of rectal lesions. The average distance from the anal verge was 9.3 cm and the mean tumor diameter confirmed by pathology measured 2.93 cm. There were no conversions from TAMIS to conventional transanal excision. While the average operating time was 86 min, four of the six TAMIS resections (67%) were completed in less than 1 h. The mean set-up time was only 1.9 min and this may be one reason that the mean operative time was considerably less than the average operative time for TEM surgery (120-140 min). In short-term follow-up, there was no morbidity or mortality observed.

CONCLUSIONS

TAMIS is a feasible alternative to TEM, providing its benefits at a fraction of the cost.