Standard diagnostic laparoscopy is superior to NOTES approaches: results of a blinded, randomized controlled porcine study

Primary and metastatic peritoneal surface malignancies

Peritoneal surface malignancies comprise a heterogeneous group of primary tumours, including peritoneal mesothelioma, and peritoneal metastases of other tumours, including ovarian, gastric, colorectal, appendicular or pancreatic cancers. The pathophysiology of peritoneal malignancy is complex and not fully understood. The two main hypotheses are the transformation of mesothelial cells (peritoneal primary tumour) and shedding of cells from a primary tumour with implantation of cells in the peritoneal cavity (peritoneal metastasis). Diagnosis is challenging and often requires modern imaging and interventional techniques, including surgical exploration. In the past decade, new treatments and multimodal strategies helped to improve patient survival and quality of life and the premise that peritoneal malignancies are fatal diseases has been dismissed as management strategies, including complete cytoreductive surgery embedded in perioperative systemic chemotherapy, can provide cure in selected patients. Furthermore, intraperitoneal chemotherapy has become an important part of combination treatments. Improving locoregional treatment delivery to enhance penetration to tumour nodules and reduce systemic uptake is one of the most active research areas. The current main challenges involve not only offering the best treatment option and developing intraperitoneal therapies that are equivalent to current systemic therapies but also defining the optimal treatment sequence according to primary tumour, disease extent and patient preferences. New imaging modalities, less invasive surgery, nanomedicines and targeted therapies are the basis for a new era of intraperitoneal therapy and are beginning to show encouraging outcomes.

Comparison in efficacy between pure NOTES peritoneoscopy with small or large endoscope and laparoscopy

OBJECTIVE

To evaluate the efficacy and systematic impact of different sized endoscopes for pure transgastric natural orifice transluminal endoscopic surgery (NOTES) peritoneoscopy relative to laparoscopy.

METHODS

A total of 15 dogs were randomly assigned to the small-sized endoscope (SS), large-sized endoscope (LS) and standard laparoscopy (SL) groups. The procedure time, visualization scores for abdominal organs, gastric incision healing times and procedure-associated complications were recorded. Blood samples were collected at 1 h preoperation and at 1 h, 12 h, 2 days and 7 days postoperation. Serum tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels as well as peripheral white blood cell (WBC) counts were analyzed.

RESULTS

Peritoneoscopy was successfully performed with both pure transgastric NOTES and laparoscopy. The peritoneoscopy required less time to complete in the SL group (44.0 ± 7.0 min) than the LS (83.0 ± 28.9 min) and SS (106.6 ± 81.3 min) groups (P < 0.01), but no statistical difference was observed between the SS and LS groups (P > 0.05). The visualization scores of peritoneal organs among the three groups did not differ significantly (P > 0.05). The gastric incision exhibited satisfactory healing in both the SS and LS groups. Moreover, serum TNF-α and IL-6 levels and WBC counts at each time point were similar among the three groups (P > 0.05).

CONCLUSIONS

Small-sized endoscope is not superior to a large-sized one for pure transgastric NOTES peritoneoscopy. Pure transgastric NOTES is not less invasive or less time-consuming than laparoscopy.

Natural orifice transluminal endoscopic surgery and upper gastrointestinal tract

Since the first transgastric natural orifice transluminal endoscopic surgery was described, various applications and modified procedures have been investigated. Transgastric natural orifice transluminal endoscopic surgery for periotoneoscopy, cholecystectomy, and appendectomy all seem viable in humans, but additional studies are required to demonstrate their benefits and roles in clinical practice. The submucosal tunneling method enhances the safety of peritoneal access and gastric closure and minimizes the risk of intraperitoneal leakage of gastric air and juice. Submucosal tunneling involves submucosal tumor resection and peroral endoscopic myotomy. Peroral endoscopic myotomy is a safe and effective treatment option for achalasia, and the most promising natural orifice transluminal endoscopic surgery procedure. Endoscopic full-thickness resection is a rapidly developing natural orifice transluminal endoscopic surgery procedure for the upper gastrointestinal tract and can be performed with a hybrid natural orifice transluminal endoscopic surgery technique (combining a laparoscopic approach) to overcome some limitations of pure natural orifice transluminal endoscopic surgery. Studies to identify the most appropriate role of endoscopic full-thickness resection are anticipated. In this article, I review the procedures of natural orifice transluminal endoscopic surgery associated with the upper gastrointestinal tract.

Use of natural orifice translumenal endoscopic surgery in the diagnosis of suspected tuberculous peritonitis: a retrospective case series of 7 patients

BACKGROUND AND OBJECTIVE

In cases of ascites of unknown etiology, tuberculosis peritonitis (TBP) is a possible cause but a diagnostic challenge. This retrospective case series assessed the effectiveness and safety of diagnostic natural orifice translumenal endoscopic surgery (NOTES(®); American Society for Gastrointestinal Endoscopy [Oak Brook, IL] and the Society of American Gastrointestinal and Endoscopic Surgeons [Los Angeles, CA]) in 7 consecutive patients with suspected TBP.

SUBJECTS AND METHODS

Between September 2011 and August 2012, peritoneal biopsy was performed using transgastric NOTES for subsequent histology in 7 consecutive hospitalized patients who presented with ascites and were diagnosed with suspected TBP. The outcome measures included diagnostic accuracy and procedure-related morbidities.

RESULTS

Diagnostic NOTES was successfully completed in all 7 patients. Peritoneoscopy with NOTES went uneventfully and lasted 5-10 minutes. Typical peritoneal nodules characteristic of TBP were identified in all patients and confirmed pathologically as TBP. No clinically significant adverse events occurred in any patients following NOTES, except for 1 patient who experienced mild and transient pyrexia. Postoperative blood culture detected no microbial growth. Follow-up upper gastrointestinal endoscopy showed that the gastric wall wound healed well with minimal scarring. All patients were prescribed a standard four-drug antituberculosis chemotherapy regimen. The treatment outcomes were determined to be effective or curative, and no relapse was detected within the follow-up period.

CONCLUSIONS

NOTES is an effective and safe diagnostic technique in patients with suspected TBP presenting as ascites of unknown etiology.

Natural orifice translumenal endoscopic surgery (NOTES) second-look peritoneoscopy for staging of limited peritoneal carcinomatosis

BACKGROUND

Over the past decades, staging laparoscopy evolved as a useful tool in multimodality treatment of patients with abdominal malignancies, especially for detection of incurable peritoneal and liver metastasis. Natural orifice translumenal endoscopic surgery (NOTES) is a new, evolving technique which represents the next logical progression in minimally invasive surgery and has theoretical advantages in comparison with standard laparoscopic surgery. A review of the current literature revealed a continuous increasing number of fundamental and clinical studies addressing NOTES approach in multimodal management of oncologic patients. Technical possibility to use this new minimally invasive approach for oncological resection of abdominal malignancies was proved by some investigators.

HYPOTHESIS

NOTES can be used as an alternative method for staging patients with limited peritoneal carcinomatosis and may have better results compared to current imaging techniques for small diameter metastatic disease.

CONCLUSIONS

With the continuous development of the NOTES techniques and technology, the second-look peritoneoscopy by NOTES may become an alternative method for staging in patients with peritoneal carcinomatosis. Nevertheless, NOTES is at a very early stage of its development, and its implementation in oncologic surgery should be made very caution, and only after careful evaluation.