Diagnostic transgastric endoscopic peritoneoscopy: extension of the initial human trial for staging of pancreatic head masses.

BACKGROUND: The validity of natural orifice transluminal endoscopic surgery (NOTES) was confirmed in a human trial of 10 patients undergoing diagnostic transgastric endoscopic peritoneoscopy (DTEP) for staging of pancreatic head masses. This report is an update with 10 additional patients in the series and includes bacterial contamination data. METHODS: The patients in this human trial were scheduled to undergo diagnostic laparoscopy for abdominal staging of a pancreatic head mass. A second surgeon, blinded to the laparoscopic findings, performed a transgastric endoscopic peritoneoscopy (TEP). The findings of laparoscopic exploration were compared with that those of the TEP. Diagnostic findings, operative times, and clinical course were recorded. Bacterial contamination data were collected for the second cohort of 10 patients. Bacterial samples were collected from the scope before use and the abdominal cavity before and after creation of the gastrotomy. Samples were assessed for bacterial counts and species identification. Definitive care was rendered based on the findings from laparoscopy. RESULTS: In this study, 20 patients underwent diagnostic laparoscopy followed by DTEP. The average time for completion of diagnostic laparoscopy was 10 min compared with 21 min for TEP. The experience acquired during the initial 10 procedures translated to a 7-min decrease in TEP time for the second 10 cases. For 19 of the 20 patients, DTEP corroborated laparoscopic findings for surgical decision making. One endoscopic and five laparoscopic biopsies were performed. Pancreaticoduodenectomy was performed for 14 patients and palliative gastrojejunostomy for 6 patients. No cross-contamination of the peritoneum or infectious complications were noted. No significant complications related to either the endoscopic or laparoscopic approach occurred. CONCLUSIONS: This study supports the authors' previous conclusions that the transgastric approach to diagnostic peritoneoscopy is feasible, safe, and accurate. The lack of documented bacterial contamination further supports the use of this technique. Technical issues, including intraabdominal manipulation and gastric closure, require further investigation.

Carbonic anhydrase IX is expressed in mesothelioma and metastatic clear cell renal cell carcinoma of the lung.

High immunohistochemical expression of carbonic anhydrase IX (CAIX) is found in clear cell renal cell carcinoma (ccRCC), but no studies have assessed CAIX in metastatic ccRCC (mccRCC) of the lung. As 75% of patients with mccRCC show lung involvement, characterization of protein expression in these lesions is warranted. This investigation analyzed CAIX immunohistochemical expression in pulmonary/pleural tumors including mccRCC (n = 22), mesothelioma (n = 19), squamous cell carcinoma (n = 27), small cell carcinoma (n = 9), and adenocarcinoma (n = 49), as well as other mesothelial lesions (n = 4). Membranous immunoreactivity was semiquantitatively evaluated for percent of cells stained and intensity. All cases of mccRCC (1+, 4.5%; 3+, 95.5%) and mesothelioma (2+, 10.5%; 3+, 89.5%) expressed CAIX. Most cases of lung squamous cell carcinoma (0, 11.1%; 1+, 25.9%; 2+, 22.2%; 3+, 40.7%) and small cell carcinoma were reactive (0, 11.1%; 1+, 22.2%; 2+, 33.3%; 3+, 33.3%), while CAIX was detected less frequently in pulmonary adenocarcinoma (0, 61.2%; 1+, 16.3%; 2+, 12.2%; 3+, 10.2%). In addition, CAIX was positive in adenomatoid tumor (3+, 100%) and mesothelial hyperplasia (3+, 100%). We demonstrate that CAIX is sensitive for mccRCC within the lung and a novel immunohistochemical marker for mesothelial proliferations, notably mesothelioma. Variable immunoreactivity is present among primary pulmonary epithelial tumors. Knowledge of expression overlap between these entities may prevent an incorrect interpretation of immunohistochemical results, particularly when limited tissue is available. As new carbonic anhydrase inhibitors are being evaluated, testing additional tumors for CAIX may lead to novel treatment options.

Safe alternative transgastric peritoneal access in humans: NOTES.

BACKGROUND: Diagnostic transgastric endoscopic peritoneoscopy has been used to evaluate the abdomen. We present our experience with transgastric endoscopic peritoneoscopy (TEP) to access the peritoneum, direct trocar placement, and perform adhesiolysis without laparoscopic visualization in patients undergoing laparoscopic Roux-en-Y gastric bypass. METHODS: Forty patients participated. There are 2 arms to the study. The initial 20 patients underwent pre-insufflation of the abdomen prior to TEP. The second 20 had no pre-insufflation. Ten patients in each arm had no surgical history. The other 10 had previous intra-abdominal procedures. TEP was performed through a gastrotomy created without laparoscopic visualization. Adhesions were visualized and taken down endoscopically prior to trocar placement. Diagnostic findings, operative times, and clinical course were recorded. RESULTS: Average TEP time was 19 min. Three patients had limited visualization due to intra-abdominal adhesions (2) and omental fat (1). Three of the 20 without and 17 of 20 with a history of intra-abdominal surgery had adhesions visualized endoscopically. Endoscopic adhesiolysis was performed in 1 and 4 patients in these groups respectively. Six occult umbilical hernias, 1 inguinal hernia, and 1 hiatal hernia were noted on endoscopic exploration. There were no complications related to intubation of the stomach, accessing the peritoneum, or endoscopic exploration. CONCLUSION: TEP is a safe and accurate means to access the peritoneum, visualize the abdominal wall, perform adhesiolysis, and direct trocar placement without laparoscopic guidance. Safe and reliable gastric closure remains the sole limitation to its clinical use outside of a protocol necessitating a gastrotomy.