Optimal Total Mesorectal Excision for Rectal Cancer: the Role of Robotic Surgery from an Expert's View

Total mesorectal excision (TME) has gained worldwide acceptance as a standard surgical technique in the treatment of rectal cancer. Ever since laparoscopic surgery was first applied to TME for rectal cancer, with increasing penetration rates, especially in Asia, an unstable camera platform, the limited mobility of straight laparoscopic instruments, the two-dimensional imaging, and a poor ergonomic position for surgeons have been regarded as limitations. Robotic technology was developed in an attempt to reduce the limitations of laparoscopic surgery. The robotic system has many advantages, including a more ergonomic position, stable camera platform and stereoscopic view, as well as elimination of tremor and subsequent improved dexterity. Current comparison data between robotic and laparoscopic rectal cancer surgery show similar intraoperative results and morbidity, postoperative recovery, and short-term oncologic outcomes. Potential benefits of a robotic system include reduction of surgeon's fatigue during surgery, improved performance and safety for intracorporeal suture, reduction of postoperative complications, sharper and more meticulous dissection, and completion of autonomic nerve preservation techniques. However, the higher cost for a robotic system still remains an obstacle to wide application, and many socioeconomic issues remain to be solved in the future. In addition, we need more concrete evidence regarding the merits for both patients and surgeons, as well as the merits compared to conventional laparoscopic techniques. Therefore, we need large-scale prospective randomized clinical trials to prove the potential benefits of robot TME for the treatment of rectal cancer

PI 3 Kinase Related Kinases-Independent Proteolysis of BRCA1 Regulates Rad51 Recruitment during Genotoxic Stress in Human Cells

The function of BRCA1 in response to ionizing radiation, which directly generates DNA double strand breaks, has been extensively characterized. However previous investigations have produced conflicting data on mutagens that initially induce other classes of DNA adducts. Because of the fundamental and clinical importance of understanding BRCA1 function, we sought to rigorously evaluate the role of this tumor suppressor in response to diverse forms of genotoxic stress.We investigated BRCA1 stability and localization in various human cells treated with model mutagens that trigger different DNA damage signaling pathways. We established that, unlike ionizing radiation, either UVC or methylmethanesulfonate (MMS) (generating bulky DNA adducts or alkylated bases respectively) induces a transient downregulation of BRCA1 protein which is neither prevented nor enhanced by inhibition of PIKKs. Moreover, we found that the proteasome mediates early degradation of BRCA1, BARD1, BACH1, and Rad52 implying that critical components of the homologous recombination machinery need to be functionally abrogated as part of the early response to UV or MMS. Significantly, we found that inhibition of BRCA1/BARD1 downregulation is accompanied by the unscheduled recruitment of both proteins to chromatin along with Rad51. Consistently, treatment of cells with MMS engendered complete disassembly of Rad51 from pre-formed ionizing radiation-induced foci. Following the initial phase of BRCA1/BARD1 downregulation, we found that the recovery of these proteins in foci coincides with the formation of RPA and Rad51 foci. This indicates that homologous recombination is reactivated at later stage of the cellular response to MMS, most likely to repair DSBs generated by replication blocks.Taken together our results demonstrate that (i) the stabilities of BRCA1/BARD1 complexes are regulated in a mutagen-specific manner, and (ii) indicate the existence of mechanisms that may be required to prevent the simultaneous recruitment of conflicting signaling pathways to sites of DNA damage

Operative Management of Small Bowel Fistulae Associated with Open Abdomen

Gastrointestinal fistulae associated with open abdomen are serious complications following trauma or other major abdominal surgery. Management is extremely difficult and the mortality is still high in spite of modern medical advances. Patients who survive initial physiological and metabolic derangements require operative closure of the fistula, which is technically demanding and poorly described in the literature. Methods: A retrospective study of patients with small bowel fistulae associated with open abdomen was performed. Only patients who were stabilized sufficiently to undergo surgical closure of the fistula were enrolled in the study. The operative techniques comprised three important steps: exploratory laparotomy and resection of small bowel fistulae with end-to-end anastomosis; bridging the abdominal wall defect with a sheet of polyglycolic acid mesh; and covering the mesh with bilateral bipedicle anterior abdominal skin flaps. Results: Eight patients were included in the study. The number of operations before surgical closure of the fistula ranged from one to six (mean, 3.6). The time from first operation to surgery for fistula closure ranged from 2.5 to 7.5 months (mean, 4.4 months). Three patients had recurrent fistula, and one died (mortality, 12.5%). Hospital stay ranged from 101 to 311 days (mean, 187 days). Conclusion: We present a method of closure of small bowel fistulae associated with open abdomen and hope that this will provide surgeons encountering such complications with a good alternative for surgical management

Pancreaticoduodenectomy with External Drainage of the Pancreatic Remnant

Leakage of the pancreaticojejunal anastomosis is a serious complication after pancreaticoduodenectomy. External drainage of the pancreatic remnant is one of several methods for reducing pancreaticojejunal anastomotic leakage or fistula. We investigated complications after pancreaticoduodenectomy with and without external drainage of the pancreatic remnant. METHODS: Patients who underwent pancreaticoduodenectomy at King Chulalongkorn Memorial Hospital, Bangkok, Thailand from November 1991 to October 2007 were enrolled. Before 2001, no external pancreatic drainage was employed during pancreaticojejunal anastomosis (non-stented group). Since 2001, external drainage of the pancreatic remnant has been routinely performed with a paediatric feeding tube (stented group). RESULTS: There were 28 patients in the non-stented group and 45 in the stented group. Stented patients had undergone significantly more previous abdominal operations, pylorus preserving pancreaticoduodenectomy, and end to end anastomosis of the pancreatic remnant and jejunal limb. Leakage of the pancreaticojejunal anastomosis or pancreatic fistula, overall complications, and re-laparotomy rate were significantly higher in the non-stented group (leakage or fistula 21.4% vs. 6.7%, overall complications 50% vs. 33.3%, and re-laparotomy 18% vs. 2.2%). The only death was in the non-stented group. CONCLUSION: External drainage of the pancreatic remnant after pancreaticoduodenectomy is an effective method for prevention of pancreaticojejunal anastomosis leakage and other related complications

Colorectal adenocarcinoma in cirrhotic patients

Colorectal carcinoma in cirrhotic patients is different from that in patients without the liver disease. The aims of this study were to evaluate the incidence of liver metastasis, postoperative mortality, and the predictors of longterm survival