Superior pathologic and clinical outcomes after minimally invasive rectal cancer resection, compared to open resection

Centromere protein A knockdown inhibits rectal cancer through O6-methylguanine DNA methyltransferase/protein tyrosine phosphatase nonreceptor type 4 axis

BACKGROUND

Centromere protein A (CENPA) exhibits an increased expression level in primary human rectal cancer tissues, but its role has not been investigated.

AIM

To clarify the specific role and mechanism of CENPA in rectal cancer progression.

METHODS

CENPA protein expression in rectal cancer tissues and cell lines were detected. CENPA was overexpressed and knocked down in SW837 and SW480 cells, and proliferation, invasion, apoptosis and epithelial-mesenchymal transition (EMT) marker protein levels were examined. O6-methylguanine DNA methyltransferase (MGMT) promoter methylation was assessed with methylation-specific polymerase chain reaction. Co-immunoprecipitation assay verified the interaction between MGMT and protein tyrosine phosphatase nonreceptor type 4 (PTPN4). SW837 cells with CENPA knockdown were injected subcutaneously into mice, and tumor growth was examined.

RESULTS

CENPA was upregulated in rectal cancer tissues and cell lines. CENPA overexpression promoted proliferation, invasion and EMT, and inhibited apoptosis in rectal cancer cells. Whereas CENPA knockdown showed the opposite results. Moreover, CENPA inhibited MGMT expression by promoting DNA methyltransferase 1-mediated MGMT promoter methylation. MGMT knockdown abolished the CENPA knockdown-mediated inhibition of rectal cancer cell progression. MGMT increased PTPN4 protein stability by inhibiting PTPN4 ubiquitination degradation via competing with ubiquitin-conjugating enzyme E2O for interacting with PTPN4. PTPN4 knockdown abolished the inhibitory effects of MGMT overexpression on rectal cancer cell progression. Moreover, CENPA knockdown inhibited xenograft tumor growth in vivo.

CONCLUSION

CENPA knockdown inhibited rectal cancer cell growth and attenuated xenograft tumor growth through regulating the MGMT/PTPN4 axis.

Nanomaterial-Based Autophagy Modulation: Multiple Weapons to Inflame Immune Systems and the Tumor Microenvironment

Autophagy, a fundamental cellular process, is a sensitive indicator of environmental shifts and is crucial for the clearance of cellular debris, the remodeling of cellular architecture, and the facilitation of cell growth and development. The interplay between stromal, tumor, and immune cells within the tumor microenvironment is intricately linked to autophagy. Therefore, the modulation of autophagy in these cell types is essential for developing effective cancer treatment strategies. This review describes the design and optimization of nanomaterials that modulate autophagy in tumor-associated and immune cells. This review elucidates the primary mechanisms by which nanomaterials induce autophagy and discusses their application in cancer therapy, underscoring the potential of these materials to eradicate cancer cells, bolster the immune response, and elicit robust, enduring antitumor immunity, thereby advancing the frontiers of oncological treatment.

Inhibition of the SERPINB5/HSP90AA1 axis restrains the proliferation and invasion of rectal cancer

BACKGROUND

The upregulation of serpin family B member 5 (SERPINB5) has been linked to the progression of rectal cancer. However, the specific roles and underlying mechanisms of SERPINB5 in rectal cancer are not fully understood.

AIM

To investigate the roles and mechanisms of SERPINB5 in rectal cancer.

METHODS

SERPINB5 protein level in rectal cancer tissues and cell lines was measured through western blot analysis. SW480 cells were transfected with pcDNA-SERPINB5 or short-hairpin RNA targeting SERPINB5 (sh-SERPINB5). Cell proliferation, invasion, and apoptosis were then evaluated. The interaction between SERPINB5 and heat shock protein 90 alpha class A member 1 (HSP90AA1) was confirmed through a co-immunoprecipitation assay. Subsequently, pcDNA-HSP90AA1 or sh-HSP90AA1 was transfected into SW480 cells, and cell progression was then detected. Moreover, rescue experiments were used to investigate the effect of the SERPINB5/HSP90AA1 axis on rectal cancer progression. Additionally, sh-SERPINB5-transfected SW480 cells were implanted into nude mice, and xenograft tumor growth was then evaluated.

RESULTS

SERPINB5 was prominently upregulated in rectal cancer tissues and cells. SERPINB5 overexpression increased SW480 cell proliferation and invasion while reducing apoptosis. In contrast, SERPINB5 knockdown had the opposite effects. Moreover, SERPINB5 could interact with HSP90AA1 and promote HSP90AA1 expression in SW480 cells. HSP90AA1 overexpression facilitated SW480 cell proliferation and invasion and restrained apoptosis. By contrast, HSP90AA1 knockdown suppressed cell progression. The upregulation of HSP90AA1 reversed the SERPINB5 silencing-mediated inhibition of SW480 cell progression. Additionally, SERPINB5 knockdown retarded the growth of rectal cancer tumors in vivo.

CONCLUSION

SERPINB5 knockdown inhibited rectal cancer cell proliferation and invasion and retarded xenograft tumor growth by inhibiting HSP90AA1 expression.

Effect of Robotic Inferior Mesenteric Artery Ligation Level on Low Anterior Resection Syndrome in Rectum Cancer

Background: Life expectancy of patients with rectal cancer is increasing day by day with innovative treatments. Low anterior resection syndrome (LARS), which disrupts the comfort of life in these patients, has become a serious problem. We aimed to evaluate the effect of high ligation (HL) and low ligation (LL) techniques on LARS in rectal cancer surgery performed with the robotic method. Materials and Methods: The data of patients diagnosed with mid-distal rectal cancer between 2016 and 2021 who underwent robotic low anterior resection by the same team in the same center with neoadjuvant chemoradiotherapy were retrospectively evaluated. Patients were divided into two groups as those who underwent HL and LL procedures. Preoperative, 8 weeks after neoadjuvant treatment, 3 and 12 months after ileostomy closure were evaluated. Results: A total of 84 patients (41 HL, 43 LL) were included in the study. There was no statistically significant difference between the demographic characteristics and pathology data of the patients. Although there was a decrease in LARS scores after neoadjuvant treatment, there was a statistically significant difference between the two groups at 3 and 12 months after ileostomy closure (P: .001, P: .015). Conclusions: In patients who underwent robotic low anterior resection, there is a statistically significant difference in the LARS score in the first 1 year with the LL technique compared with that of the HL technique, and the LL technique has superiority in reducing the development of LARS between the two oncologically indistinguishable methods.

Robotic Total Mesorectal Excision for Low Rectal Cancer: A Narrative Review and Description of the Technique

Robotic surgery may offer significant advantages for treating extraperitoneal rectal cancer. Although laparoscopy has been shown to be safe and effective, laparoscopic total mesorectal excision (TME) remains technically challenging and is still performed in selected centers. Robotic anterior resection (RAR) may overcome the drawback of conventional laparoscopy, providing high-quality surgery with favorable oncological outcomes. Moreover, recent data show how RAR offers clinical and oncological benefits when affording difficult TMEs, such as low and advanced rectal tumors, in terms of complication rate, specimen quality, recurrence rate, and survival. This series aims to review the most recent and relevant literature, reporting mid- and long-term oncological outcomes and focusing on minimally invasive RAR for low rectal cancer.

The learning curve of laparoscopic rectal cancer surgery of millennial surgeons: Lessons for a safe implementation in low- and middle-income countries

Objective

This study aimed to analyse the learning curve (LC) in laparoscopic rectal cancer resections of 2 millennial surgeons during the implementation of the first laparoscopic rectal cancer surgery programme in low- and middle-income country (LMIC) cancer centre.

Methods

All consecutive patients operated by two millennial surgeons for primary rectal adenocarcinoma between January 2018 and March 2020 were included. The LC was analysed for operative duration and conversion to open surgery using both cumulative sum (CUSUM) and/or variable life-adjusted display (VLAD) charts.

Results

Eighty-four patients were included, 45 (53.6%) men with a mean age of 57.3 years. Abdominoperineal resection was performed in 31 (36.9%) cases and resections were extended to other organs in 20 (23.8%) patients. Thirteen patients (15.5%) had conversion to open surgery. Using CUSUM, Learning curve based on conversion was completed at 12 cases for the first surgeon versus 10 cases for the second. While using VLAD and learning curve-CUSUM (LC-CUSUM), the cases needed were 26 vs 24 respectively. The median operative duration was 314 min with a LC completed at cases (17 vs. 26), and (18 vs. 29) using, respectively, standard and LC-CUSUM.

Conclusions

This study shows a safe and short LC of millennial surgeons during the implementation of a laparoscopic rectal cancer surgery in an LMIC cancer centre, and the valuable use of modern statistical methods in the prospective assessment of LC safety during surgical training.

A Narrative Review of the Usefulness of Indocyanine Green Fluorescence Angiography for Perfusion Assessment in Colorectal Surgery

Anastomotic leakage is one of the most dreaded complications of colorectal surgery and is strongly associated with tissue perfusion. Indocyanine green fluorescence angiography (ICG-FA) using indocyanine green and near-infrared systems is an innovative technique that allows the visualization of anastomotic perfusion. Based on this information on tissue perfusion status, surgeons will be able to clearly identify colorectal segments with good blood flow for safer colorectal anastomosis. The results of several clinical trials indicate that ICG-FA may reduce the risk of AL in colorectal resection; however, the level of evidence is not high, as several other studies have failed to demonstrate a reduction in the risk of AL. Several large-scale RCTs are currently underway, and their results will determine whether ICG-FA is, indeed, useful. The major limitation of the current ICG-FA evaluation method, however, is that it is subjective and based on visual assessment by the surgeon. To complement this, the utility of objective evaluation methods for fluorescence using quantitative parameters is being investigated. Promising results have been reported from several clinical trials, but all trials are preliminary owing to their small sample size and lack of standardized protocols for quantitative evaluation. Therefore, appropriately standardized, high-quality, large-scale studies are warranted.

Endoscopic vacuum-assisted surgical closure (EVASC) of anastomotic defects after low anterior resection for rectal cancer; lessons learned

BACKGROUND

Endoscopic vacuum-assisted surgical closure (EVASC) is an emerging treatment for AL, and early initiation of treatment seems to be crucial. The objective of this study was to report on the efficacy of EVASC for anastomotic leakage (AL) after rectal cancer resection and determine factors for success.

METHODS

This retrospective cohort study included all rectal cancer patients treated with EVASC for a leaking primary anastomosis after LAR at a tertiary referral centre (July 2012-April 2020). Early initiation (≤ 21 days) or late initiation of the EVASC protocol was compared. Primary outcomes were healed and functional anastomosis at end of follow-up.

RESULTS

Sixty-two patients were included, of whom 38 were referred. Median follow-up was 25 months (IQR 14-38). Early initiation of EVASC (≤ 21 days) resulted in a higher rate of healed anastomosis (87% vs 59%, OR 4.43 [1.25-15.9]) and functional anastomosis (80% vs 56%, OR 3.11 [1.00-9.71]) if compared to late initiation. Median interval from AL diagnosis to initiation of EVASC was significantly shorter in the early group (11 days (IQR 6-15) vs 70 days (IQR 39-322), p < 0.001). A permanent end-colostomy was created in 7% and 28%, respectively (OR 0.18 [0.04-0.93]). In 17 patients with a non-defunctioned anastomosis, and AL diagnosis within 2 weeks, EVASC resulted in 100% healed and functional anastomosis.

CONCLUSION

Early initiation of EVASC for anastomotic leakage after rectal cancer resection yields high rates of healed and functional anastomosis. EVASC showed to be progressively more successful with the implementation of highly selective diversion and early diagnosis of the leak.

Analysis of bowel function, urogenital function, and long-term follow-up outcomes associated with robotic and laparoscopic sphincter-preserving surgical approaches to total mesorectal excision in low rectal cancer: a retrospective cohort study

OBJECTIVE

The present study comparatively analyzed short-term clinical effectiveness and long-term follow-up endpoints associated with robotic-assisted sphincter-preserving surgery (RAS) and laparoscopic-assisted sphincter-preserving surgery (LAS) when used to treat low rectal cancer.

METHOD

Within such a single-center retrospective cohort analysis, low rectal cancer patients that underwent RAS (n=200) or LAS (n=486) between January 2015 and beginning of July 2018 were enrolled.

RESULTS

The mean operative durations in the RAS and LAS cohorts were 249±64 min and 203±47 min, respectively (P<0.001). Temporary ileostomy rates in the RAS and LAS cohorts were 64.5% and 51.6% (P = 0.002). In addition, major variations across such cohorts regarding catheter removal timing, time to liquid intake, time to first leaving bed, and length of hospitalization (all P<0.001). This distal resection margin distance within the RAS cohort was diminished in comparison to LAS cohort (P=0.004). For patients within the LAS cohort, the time required to recover from reduced urinary/female sexual function was > 6 months post-surgery (P<0.0001), whereas within the RAS cohort this interval was 3 months (P<0.0001). At 6 months post-surgery, male sexual function within RAS cohort was improved in comparison to LAS cohort (P<0.001). At 6 months post-surgery, Wexner scores revealed similar results (P<0.001). No major variations within overall or disease-free survival were identified across these cohorts at 3 or 5 years post-surgery.

CONCLUSION

Robotic sphincter-preserving surgery is a safe and effective surgical technique in low rectal patients in terms of postoperative oncological safety and long-term endpoints. And the RAS strategy provides certain additional benefits with respect to short-term urogenital/anorectal functional recovery in treated patients compared to LAS.

Potentials of long non-coding RNAs as biomarkers of colorectal cancer

Colorectal cancer (CRC) is the third most common malignant tumor worldwide and the fourth major cause of cancer-related death, with high morbidity and increased mortality year by year. Although significant progress has been made in the therapy strategies for CRC, the great difficulty in early diagnosis, feeble susceptibility to radiotherapy and chemotherapy, and high recurrence rates have reduced therapeutic efficacy resulting in poor prognosis. Therefore, it is urgent to understand the pathogenesis of CRC and unravel novel biomarkers to improve the early diagnosis, treatment and prediction of CRC recurrence. Long non-coding RNAs (lncRNAs) are non-coding RNAs with a length of more than 200 nucleotides, which are abnormally expressed in tumor tissues and cell lines, activating or inhibiting specific genes through multiple mechanisms including transcription and translation. A growing number of studies have shown that lncRNAs are important regulators of microRNAs (miRNAs, miRs) expression in CRC and may be promising biomarkers and potential therapeutic targets in the research field of CRC. This review mainly summarizes the potential application value of lncRNAs as novel biomarkers in CRC diagnosis, radiotherapy, chemotherapy and prognosis. Additionally, the significance of lncRNA SNHGs family and lncRNA-miRNA networks in regulating the occurrence and development of CRC is mentioned, aiming to provide some insights for understanding the pathogenesis of CRC and developing new diagnostic and therapeutic strategies.

Comparison of Survival Among Adults With Rectal Cancer Who Have Undergone Laparoscopic vs Open Surgery: A Meta-analysis

IMPORTANCE

Two large randomized clinical trials (RCTs) found that laparoscopic surgery failed to yield noninferior pathologic outcomes compared with open surgery for patients with rectal cancer. The results raised concerns regarding the effectiveness of the laparoscopic approach for patients with rectal cancer.

OBJECTIVE

To compare the long-term oncologic outcomes of laparoscopic and open surgery for patients with rectal cancer.

DATA SOURCES

PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials were searched from database inception to August 13, 2021. Studies published in English were retrieved.

STUDY SELECTION

The meta-analysis included RCTs that compared laparoscopic surgery with open surgery for patients with rectal cancer and reported the outcome of disease-free survival (DFS) or overall survival (OS). The following exclusion criteria were used: (1) non-RCTs, (2) studies without long-term survival outcomes of interest, and (3) studies that did not report Kaplan-Meier survival curves.

DATA EXTRACTION AND SYNTHESIS

This meta-analysis was performed in line with the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline for individual participant data development groups. Individual participant data on DFS and OS were extracted from the published Kaplan-Meier survival curves. One-stage and 2-stage meta-analyses were performed.

MAIN OUTCOMES AND MEASURES

Meta-analyses were conducted for DFS and OS. Hazard ratios (HRs) were used as effective measures.

RESULTS

Of 8471 records screened, 10 articles with 12 RCTs and 3709 participants were selected. The reconstructed survival curves for the combined population showed that the 5-year estimated DFS rates were 72.2% (95% CI, 69.4%-74.8%) for the laparoscopic group and 70.1% (95% CI, 67.0%-73.0%) for the open surgery group, and the 5-year estimated OS rates were 76.2% (95% CI, 73.8%-78.5%) for the laparoscopic group and 72.7% (95% CI, 69.8%-75.3%) for open surgery group. In 1-stage meta-analyses, DFS had a nonsignificant HR of 0.92 (95% CI, 0.80-1.06; P = .26), which suggested that DFS in the laparoscopic and open surgery groups was comparable; however, OS was significantly better in the laparoscopic group (HR, 0.85; 95% CI, 0.74-0.97; P = .02). The results were confirmed by 2-stage meta-analyses and were validated by sensitivity analysis with large RCTs.

CONCLUSIONS AND RELEVANCE

A similar DFS but significantly better OS were found for patients who have undergone laparoscopic surgery compared with open surgery for rectal cancer. These findings address concerns regarding the effectiveness of laparoscopic surgery and support the routine use of laparoscopic surgery for patients with rectal cancer.

Temporary vs. permanent stoma: factors associated with the development of complications and costs for rectal cancer patients

OBJECTIVE

To compare in-hospital complication rates and treatment costs between rectal cancer patients receiving permanent and temporary stomas. Surgical complications and costs associated with permanent stoma formation are still poorly understood. While choosing between the two stoma options is usually based on clinical and technical factors, disparities exist.

METHODS

Patients with rectal cancer, stoma formation, complications, and cost of care were identified from the Florida Agency for Health Care Administration Discharge Database. Rectal cancer patients who underwent elective surgery and received a permanent or temporary stoma were identified using ICD-10 codes. Patients who underwent colostomy with resection were included in the "Permanent stoma" group, and those who underwent "resection with ileostomy" were included in the "temporary stoma" group. Multivariable models compared patients receiving temporary vs. permanent stomas.

RESULTS

Regression models revealed no difference in the odds of having a complication between patients who obtained permanent versus temporary stoma (OR 0.96, 95% CI: 0.70-1.32). Further, after adjusting for the number of surgeries, demographic variables, socioeconomic and regional factors, comorbidities, and type of surgery, there was a significant difference between permanent and temporary stomas for rectal cancer (ß - 0.05, p = 0.03) in the log cost of creating a permanent stoma.

CONCLUSION

Our findings suggest there are no differences associated with complications, and reduced cost for permanent compared to temporary stomas. Increased costs are also associated with receiving minimally invasive surgery. As a result, disparities associated with receipt of MIS could ultimately influence the type of stoma received.

Update on Minimally Invasive Surgical Approaches for Rectal Cancer

PURPOSE OF REVIEW

This review aims to clarify the current role of minimally invasive surgery in the treatment of rectal cancer, highlighting short- and long-term outcomes from the latest trials and studies.

RECENT FINDINGS

Data from previous trials has been conflicting, with some failing to demonstrate non-inferiority of laparoscopic surgical resection of rectal cancer compared to an open approach and others demonstrating similar clinical outcomes. Robot-assisted surgery was thought to be a promising solution to the challenges faced by laparoscopic surgery, and even though the only randomized controlled trial to date comparing these two techniques did not show superiority of robot-assisted surgery over laparoscopy, more recent retrospective data suggests a statistically significant higher negative circumferential resection margin rate, decreased frequency of conversion to open, and less sexual and urinary complications. Minimally invasive surgery techniques for resection of rectal cancer, particularly robot-assisted, offer clear short-term peri-operative benefits over an open approach; however, current data has yet to display non-inferiority in terms of oncological outcomes.

Improving postoperative outcome in rectal cancer surgery: Enhanced Recovery After Surgery in an era of increasing laparoscopic resection

PURPOSE

The Enhanced Recovery After Surgery (ERAS) protocol reduces complications and length of stay (LOS) in colon cancer, but implementation in rectal cancer is different because of neo-adjuvant therapy and surgical differences. Laparoscopic resection may further improve outcome. The aim of this study was to evaluate the effects of introducing ERAS on postoperative outcome after rectal cancer resection in an era of increasing laparoscopic resections.

MATERIALS AND METHODS

Patients who underwent elective rectal cancer surgery from 2009 till 2015 were included in this observational cohort study. In 2010, ERAS was introduced and adherence to the protocol was registered. Open and laparoscopic resections were compared. With regression analysis, predictive factors for postoperative outcome and LOS were identified.

RESULTS

A total of 499 patients were included. The LOS decreased from 12.3 days in 2009 to 5.7 days in 2015 (p = 0.000). Surgical site infections were reduced from 24% in 2009 to 5% in 2015 (p = 0.013) and postoperative ileus from 39% in 2009 to 6% in 2015 (p = 0.000). Only postoperative ERAS items and laparoscopic surgery were associated with an improved postoperative outcome and shorter LOS.

CONCLUSIONS

ERAS proved to be feasible, safe, and contributed to improving short-term outcome in rectal cancer resections. The benefits of laparoscopic surgery may in part be explained by reaching better ERAS adherence rates. However, the laparoscopic approach was also associated with anastomotic leakage. Despite the potential of bias, this study provides an insight in effects of ERAS and laparoscopic surgery in a non-randomized real-time setting.

LncRNA EGOT/miR-211-5p Affected Radiosensitivity of Rectal Cancer by Competitively Regulating ErbB4

BACKGROUND/AIMS

Long non-coding ribonucleic acids (lncRNAs) are involved in the progression of cancers and affect the response to radiation therapy. This study was to investigate the mechanism of lncRNA EGOT in the radiosensitivity of rectal cancer.

METHODS

The mRNA expression of EGOT, miR-211-5p and ErbB4 in rectal cancer tissues and cells was detected by qRT-PCR. The protein expression of ErbB4 was detected by Western blot. Dual-luciferase reporter assay and ribonucleic acid immunoprecipitation (RIP) were used to confirm the interaction between EGOT and miR-211-5p or miR-211-5p and ErbB4. Transfection technology was used to down-regulate and up-regulate the expression of EGOT and miR-211-5p in rectal cancer cells, respectively. MTT, colony formation and flow cytometry were used to detect the effect of EGOT and miR-211-5p on proliferation, invasion, migration and apoptosis of rectal cancer cells.

RESULTS

The expression of EGOT was up-regulated in rectal cancer tissues and cells, and the expression of EGOT was related to the late stage of pathology. EGOT knockdown inhibited the proliferation and colony formation of rectal cancer cells and induced the apoptosis of rectal cancer cells. Moreover, EGOT knockdown was significantly enhanced the effects of radiotherapy on rectal cancer in vivo and in vitro. Furthermore, EGOT was found to serve as a sponge of miR-211-5p, and ErbB4 was a downstream target of miR-211-5p. EGOT enhanced the expression of ErbB4 by regulating miR-211-5p. MiR-211-5p inhibitor restored the effect of EGOT knockdown on the radiosensitivity of rectal cancer.

CONCLUSION

Down-regulation of EGOT could inhibit the growth of rectal cancer cells by regulating the miR-211-5p/ErbB4 axis and improve the radiosensitivity of rectal cancer cells. EGOT may be a new therapeutic target for rectal cancer.

Real-world comparison of curative open, laparoscopic and robotic resections for sigmoid and rectal cancer-single center experience

There has been an increase in the utilization of robotic surgery in addition to traditional open or laparoscopic approaches. Aim of this study is to compare the short-term outcomes for open, laparoscopic, and robotic surgery for rectal and sigmoid cancer. One hundred and forty-seven patients (open n = 48, laparoscopic n = 49, robotic n = 50) undergoing curative resections by two surgeons between 2013 and 2020 were included. Data analyzed included patient demographics, tumor characteristics, length of stay, post-operative outcomes, and pathologic surrogates of oncologic results, including total mesorectal excision (TME) quality, circumferential resection margin (CRM) involvement and lymph node (LN) yield. Median age of population was 68 years (IQR 59-73), majority (68%) were males. Median distance from anal verge in the robotic surgery group was 8 cm, compared to 15 and 14.5 cm in the open and laparoscopic groups, respectively, p = 0.029, (laparoscopic vs robotic, p = 0.005 and open vs robotic, p = 0.027). Proportion of patients who received neoadjuvant radiotherapy in robotic surgery group was higher, p = 0.04. In sub-group of tumors between 3 and 7 cm from anal verge more patients in the robotic surgery group had sphincter preservation, p = 0.006. Length of stay, maximum C-reactive protein, and white blood cell rise favored minimally invasive approaches compared to open surgery. There were no differences in post-operative complications, lymph node yield or CRM positivity rate between the three groups. Robotic surgery approach is safe and allows sphincter preservation without compromising TME quality in rectal cancer surgery.

Development and validation of a porcine organ model for training in essential laparoscopic surgical skills

OBJECTIVES

To develop a wet laboratory training model for learning core laparoscopic surgical skills and evaluating learners' competency level outside the operating room.

METHODS

Participants completed three tasks (task 1: tissue dissection around the aorta; task 2: tissue dissection and division of the renal artery; task 3: renal parenchymal closure). Each performance was video recorded and subsequently evaluated by two experts, according to the Global Operative Assessment of Laparoscopic Skills and task-specific metrics that we developed (Assessment Sheet of Laparoscopic Skills in Wet Lab score). Mean scores were used for analyses. The subjective mental workload was also assessed (NASA Task Load Index).

RESULTS

The 54 participants included 32 urologists, eight young trainees and 14 medical students. A total of 13 participants were categorized as experts (≥50 laparoscopic surgeries), eight as intermediates (10-49) and 33 as novices (0-9). There were significant differences in the Global Operative Assessment of Laparoscopic Skills and Assessment Sheet of Laparoscopic Skills in Wet Lab scores among the three groups in all three tasks. Higher NASA Task Load Index scores were observed in novices, and there were significant differences in tasks 1 (Kruskal-Wallis test, P = 0.0004) and 2 (P = 0.0002), and marginal differences in task 3 (P = 0.0745) among the three groups.

CONCLUSIONS

Our training model has good construct validity, and differences in the NASA Task Load Index score reflect previous laparoscopic surgical experiences. Our findings show the ability to assess both laparoscopic surgical skills and mental workloads, which could help educators comprehend trainees' level outside the operating room. Given the decreasing opportunity to carry out pure laparoscopic surgeries because of the dissemination of robotic surgery, especially in urology, our model can offer practical training opportunities.