Metformin is a metabolic modulator and radiosensitiser in rectal cancer.

Resistance to neoadjuvant chemoradiation therapy, is a major challenge in the management of rectal cancer. Increasing evidence supports a role for altered energy metabolism in the resistance of tumours to anti-cancer therapy, suggesting that targeting tumour metabolism may have potential as a novel therapeutic strategy to boost treatment response. In this study, the impact of metformin on the radiosensitivity of colorectal cancer cells, and the potential mechanisms of action of metformin-mediated radiosensitisation were investigated. Metformin treatment was demonstrated to significantly radiosensitise both radiosensitive and radioresistant colorectal cancer cells in vitro. Transcriptomic and functional analysis demonstrated metformin-mediated alterations to energy metabolism, mitochondrial function, cell cycle distribution and progression, cell death and antioxidant levels in colorectal cancer cells. Using ex vivo models, metformin treatment significantly inhibited oxidative phosphorylation and glycolysis in treatment naïve rectal cancer biopsies, without affecting the real-time metabolic profile of non-cancer rectal tissue. Importantly, metformin treatment differentially altered the protein secretome of rectal cancer tissue when compared to non-cancer rectal tissue. Together these data highlight the potential utility of metformin as an anti-metabolic radiosensitiser in rectal cancer.

Attitudes and access of Irish general surgery trainees to robotic surgical training.

Background: Although the use of robotic-assisted surgery is now mainstream for procedures such as robotic prostatectomy and hysterectomy, its role in general surgery is less well established. Access to training in robotics for general surgery trainees in the Republic of Ireland is variable. Further, there are no data on specific attitudes of Irish trainees toward the role of robotics. We aimed to establish attitudes of Irish general surgery trainees toward the perceived utility of robotic surgery as well as access and satisfaction with training. Methods: A survey was disseminated to trainees in the Republic of Ireland enrolled in a General Surgery training scheme via email and social media. Data collected included stage of training, intended subspecialty, interest in developing robotic skills, previous exposure to robotic surgery, satisfaction with current access to robotic training, and opinion on formally incorporating training in robotics into the general surgery curriculum. Results: The response rate was 53.8%. Of these, 83% reported interest in training in robotics and 66% anticipated using the technology regularly in consultant practice. Previous exposure to robotic-assisted surgery was significantly predictive of interest in developing the skillset (P = .014). More than 71% of trainees reported that they were not satisfied with access to robotic training. Of those satisfied with access, 40% felt there was a role for incorporating robotic training into the curriculum compared to 68% of those dissatisfied. Conclusion: Irish general surgery trainees perceive robotic-assisted surgery to be highly relevant to their future practice. There is an unmet need to provide additional training in the skillset.

Robotic versus laparoscopic anterior resections for rectal and rectosigmoid cancer: an institutional experience.

INTRODUCTION: Colorectal surgery has evolved with the advent of laparoscopic techniques and now robotic-assisted surgery. There is significant literature supporting the use of laparoscopic techniques over open surgery with evidence of enhanced post-operative recovery, reduced use of opioids, smaller incisions and equivalent oncological outcomes. Robotic minimally invasive surgery addresses some of the limitations of laparoscopic surgery, providing surgical precision and improvements in perception and dexterity with a resulting decrease in tissue damage. METHODS: We retrospectively reviewed the medical records of patients who underwent robotic-assisted anterior resection for cancer of the rectum or rectosigmoid junction in our institution since our robotic programme began in 2017. Patient demographics were identified via electronic databases and patient charts. A matched cohort of laparoscopic cases was identified. RESULTS: A total of 51 consecutive robotic-assisted anterior resections were identified and case matched with laparoscopic resections for comparison. Robotic-assisted surgery was associated with a shorter length of stay (p = 0.04), reduced initial post-operative analgesia requirements (p < 0.01) and no significant difference in time to bowel movement or stoma functioning (p = 0.84). All patients had an R0 resection, and there was no statistical difference in lymph node yield between the groups (p = 0.14). Robotic surgery was associated with a longer operative duration (p < 0.001). CONCLUSION: In this early experience, robotic surgery has proven feasible and safe and is comparable to laparoscopic surgery in terms of completeness of resection and recovery. As costs and operating times decline and as technology progresses, robotic surgery may one day replace traditional laparoscopic techniques.

Safe adoption of robotic colorectal surgery using structured training: early Irish experience.

Robotic surgery enhances the precision of minimally invasive surgery through improved three-dimensional views and articulated instruments. There has been increasing interest in adopting this technology to colorectal surgery and this has recently been introduced to the Irish health system. This paper gives an account of our early institutional experience with adoption of robotic colorectal surgery using structured training. Analysis was conducted of a prospectively maintained database of our first 55 consecutive robotic colorectal cases, performed by four colorectal surgeons, each at the beginning of his robotic surgery experience, using the Da Vinci Si® system and undergoing training as per the European Academy of Robotic Colorectal Surgery (EARCS) programme. Overall surgical and oncological outcomes were interrogated. Fifty-five patients underwent robotic surgery between January 2017 and January 2018, M:F 34:21, median age (range) 60 (35-87) years. Thirty-three patients had colorectal cancer and 22 had benign pathologies. Eleven rectal cancer patients had neoadjuvant chemoradiotherapy. BMI was > 30 in 21.8% of patients and 56.4% of patients had previous abdominal surgery. Operative procedures performed were low anterior resection (n = 19), sigmoid colectomy (n = 9), right colectomy (n = 22), ventral mesh rectopexy (n = 3), abdominoperineal resection (n = 1) and reversal of Hartmann's procedure (n = 1). Median blood loss was 40 ml (range 0-400). Mean operative time (minutes) was 233 (SD 79) for right colectomy and 368 (SD 105) for anterior resection. Median length of hospital stay was 6 days (IQR 5-7). There was no 30-day mortality, intraoperative complications, conversion to laparoscopic or open, or anastomotic leakage. Median lymph nodes harvest was 15 in non-neoadjuvant cases (range 7-23) and 8 in neoadjuvant cases (2-14). Our early results demonstrate that colorectal robotic surgery can be adopted safely for both benign and neoplastic conditions using a structured training programme without compromising clinical or oncological outcomes. The early learning curve can be time intensive.

Clinical research of holmium laser therapy in extramammary Paget's disease.

This study aims to investigate the safety and efficiency of the holmium laser therapy in extramammary Paget's disease. The clinical data of 61 patients was collected since 2002 to 2012, confirmed as non-subcutaneous invasive extramammary Paget's disease by biopsy and underwent surgery. All patients were divided into two groups. Group A included 30 patients who underwent the holmium laser therapy. Group B included 31 patients who underwent the traditional surgical therapy. The clinical data of all patients included preoperative, intraoperative, and postoperative management and follow-up records. Compared with the traditional operation group, the holmium laser group had a shorter operation time and was easier to perform. There were no significant differences between the two groups in cases of intraoperative and postoperative complications, the recurrence-free survival, and the disease-specific survival. But the holmium laser group had a longer recovery time than the traditional operation group in large and deep nidus. Multiple-factor analysis of prognostic parameters of 61 patients confirmed that any of these two methods chosen was not a prognostic parameter for recurrence-free survival. The holmium laser therapy might prove to be a preferable alternative to the traditional operative therapy of extramammary Paget's disease. However, the holmium laser therapy did not demonstrate to have an obvious advantage over traditional operative therapy in the recurrence-free survival and the disease-specific survival.

Development and evaluation of a simulator-based laparoscopic training program for surgical novices.

BACKGROUND: The use of simulation to train novice surgeons in laparoscopic skills is becoming increasingly popular. To maximize benefit from simulation, training needs to be delivered and assessed in a structured manner. This study aimed to define performance goals, demonstrate construct validity of the training program, and evaluate whether novice surgeons could reach the preset performance goals. METHODS: Nine expert laparoscopic surgeons established performance goals for three basic modules of an augmented-reality laparoscopic simulator. The three laparoscopic modules were used by 40 novice surgeons and 40 surgical trainees (postgraduate years [PGYs] 1-4). The performance outcomes were analyzed across the different groups (novice, PGYs 1 and 2, PGYs 3 and 4, expert) to determine construct validity. Then 26 recruited novices trained on the three modules with the aim of reaching the performance goals. RESULTS: The results demonstrated a significant difference in performance between all levels of experience for time (p < 0.001), motion analysis (p < 0.001), and error score (p < 0.001), thus demonstrating construct validity. All 26 novice surgeons significantly improved in performance with repetition for the metrics of time (p < 0.001) and motion analysis (p < 0.001). For two of the modules, the proficiency goals were reached in fewer than 10 trials by 80% of the study participants. CONCLUSION: Basic skills in laparoscopic surgery can be learned and improved using proficiency-based simulation training. It is possible for novice surgeons to achieve predefined performance goals in a reasonable time frame.