Circumferential Resection Margin Involvement Rate Research Articles

Impact of robotic total mesorectal excision upon pathology metrics in overweight males with low rectal cancer: a pooled analysis of 836 cases.

The aim of this pooled analysis was to evaluate the impact of robotic total mesorectal excision (TME) on pathology metrics in Male Overweight patients with Low rectal cancer (MOL). This was a multicenter retrospective pooled analysis of data. Two groups were defined: MOL (Male, Overweight, Low rectal cancer) and non-MOL. Overweight was defined as BMI ≥ 25kg/m2. Low rectal cancer was defined as cancer within 6cm from the anal verge. The primary endpoints of this study were histopathological metrics, namely circumferential resection margin (CRM) (mm), CRM involvement rate (%), and the quality of TME. Circumferential resection margin (CRM) was involved if < 1mm. 836 (106 MOL and 730 non-MOL) patients that underwent robotic TME by six surgeons over 3years were compared. No significant differences in demographics and perioperative variables were found, except for operating time, distal margin, and number of lymph nodes harvested. CRM involvement rate did not significantly differ (7.5% vs. 5.5%, p = 0.395). Mean CRM was statistically significantly narrower in MOL patients (6.6 vs. 7.7mm, p = 0.04). Quality of TME did not differ. Distance of tumor from the anal verge was the only independent predictor of CRM involvement. Robotic TME may provide optimal pathology metrics in overweight males with low rectal cancer. Although CRM was a few millimeters narrower in MOL, the values were within the range of uninvolved margins making the difference statistically significant, but not clinically. Being MOL was not a risk factor for involvement of circumferential resection margin.

Surgical Techniques for Abdominoperineal Resection for Rectal Cancer: One Size Does Not Fit All.

Abdominoperineal resection (APR) of rectal cancer is associated with poorer oncological outcomes than anterior resection. This may be due to higher rates of intra-operative perforation (IOP) and circumferential resection margin (CRM) involvement causing higher recurrence rates and surgical complications. To address these concerns, several centers advocated a change in technique from a standard APR to a more radical extra-levator abdominoperineal excision (ELAPE). Initial reports showed that ELAPE reduced IOP rates and CRM involvement but increased wound complications and longer surgical duration. However, many of these studies had unacceptable rates of IOP and CRM before retraining in ELAPE. This may indicate that it was a sub-optimal surgical technique, which improved upon training, that had influenced the high CRM and IOP rates rather than the technique itself. Subsequent studies demonstrated that the CRM involvement rate for ELAPE was not always lower than for standard APR and, in some cases, significantly higher. The morbidity of ELAPE can be high, with studies reporting higher adverse events than APR, especially in terms of wound complications from the larger perineal incision required in ELAPE. Whether ELAPE improves short- or long-term oncological outcomes for patients has not been clearly demonstrated. The authors propose that all centers performing rectal cancer surgery audit surgical outcomes of patients undergoing APR or ELAPE and examine CRM involvement, IOP rates, and local recurrence rates, preferably through a national body. If rates of adverse technical or oncological outcomes exceed acceptable levels, then retraining in the appropriate surgical techniques may be indicated.

Does the learning curve in robotic rectal cancer surgery impact circumferential resection margin involvement and reoperation rates? A risk-adjusted cumulative sum analysis.

The aim of this study was to evaluate the impact of surgeons' learning curve in robotic surgery for rectal cancer on circumferential resection margin (CRM) involvement and reoperation rates. Learning curve data were prospectively collected from four centers. Patients undergoing robotic proctectomy for resectable rectal cancer were included. CRM was involved when ≥1 mm. TME quality was classified as complete, nearly complete, or incomplete. T-test and χ2 tests were used to compare continuous and categorical variables, respectively. Risk-adjusted cumulative sum (RA-CUSUM) analysis was utilized to evaluate the effect of the learning curve on primary endpoints. Univariate analysis of potential risk factors for CRM involvement and reoperation was performed. Factors with the P value ≤0.2 were included in the multivariate logistic regression model for further RA-CUSUM analysis. A total of 221 patients (80, 36, 62, and 43 patients operated on by surgeons 1, 2, 3, and 4, respectively) who underwent robotic surgery for rectal cancer during the surgeons' learning curves were included. CRM involvement rate was 0%, 11%, 3%, and 5% in surgeons 1, 2, 3, and 4, respectively. Reoperation rate was 3.7%, 8.3%, 4.8%, and 11.6%, respectively. RA-CUSUM analysis of CRM involvement (R2=0.9886) and reoperation (R2=0.9891) found a statistically significant decreasing trend in aggregate CUSUM values throughout the learning curve. This study found a continued significant decrease in CRM involvement and reoperation rates throughout the learning curve in robotic rectal cancer surgery.

Does the learning curve in robotic rectal cancer surgery impact circumferential resection margin involvement and reoperation rates? A risk-adjusted cumulative sum analysis

Background The aim of this study was to evaluate the impact of surgeons' learning curve in robotic surgery for rectal cancer on circumferential resection margin (CRM) involvement and reoperation rates. Methods Learning curve data were prospectively collected from four centers. Patients undergoing robotic proctectomy for resectable rectal cancer were included. CRM was involved when ≥1 mm. TME quality was classified as complete, nearly complete, or incomplete. T-test and Chi-square tests were used to compare continuous and categorical variables, respectively. Risk-adjusted cumulative sum (RA-CUSUM) analysis was utilized to evaluate the effect of the learning curve on primary endpoints. Univariate analysis of potential risk factors for CRM involvement and reoperation was performed. Factors with the p-value ≤0.2 were included in the multivariate logistic regression model for further RA-CUSUM analysis. Results A total of 221 patients (80, 36, 62, and 43 patients operated on by surgeons 1, 2, 3, and 4, respectively) who underwent robotic surgery for rectal cancer during the surgeons' learning curves were included. CRM involvement rate was 0%, 11%, 3%, and 5% in surgeons 1, 2, 3, and 4, respectively. Reoperation rate was 3.7%, 8.3%, 4.8%, and 11.6%, respectively. RA-CUSUM analysis of CRM involvement (R2=0.9886) and reoperation (R2=0.9891) found a statistically significant decreasing trend in aggregate CUSUM values throughout the learning curve. Conclusions This study found a continued significant decrease in CRM involvement and reoperation rates throughout the learning curve in robotic rectal cancer surgery.

The quality of lymph node harvests in extralevator abdominoperineal excisions

BackgroundLymph node (LN) harvest in colorectal cancer resections is a well-recognised prognostic factor for disease staging and determining survival, particularly for node-negative (N0) diseases. Extralevator abdominoperineal excisions (ELAPE) aim to prevent “waisting” that occurs during conventional abdominoperineal resections (APR) for low rectal cancers, and reducing circumferential resection margin (CRM) infiltration rate. Our study investigates whether ELAPE may also improve the quality of LN harvests, addressing gaps in the literature.MethodsThis retrospective observational study reviewed 2 sets of 30 consecutive APRs before and after the adoption of ELAPE in our unit. The primary outcomes are the total LN counts and rates of meeting the standard of 12-minimum, particularly for those with node-negative disease. The secondary outcomes are the CRM involvement rates. Baseline characteristics including age, sex, laparoscopic or open surgery and the use of neoadjuvant chemoradiotherapy were accounted for in our analyses.ResultsMedian LN counts were slightly higher in the ELAPE group (16.5 vs. 15). Specimens failing the minimum 12-LN requirements were almost significantly fewer in the ELAPE group (OR 0.456, P = 0.085). Among node-negative rectal cancers, significantly fewer resections failed the 12-LN standard in the ELAPE group than APR group (OR 0.211, P = 0.044). ELAPE led to a near-significant decrease in CRM involvement (OR 0.365, P = 0.088). These improvements were persistently observed after taking into account baselines and potential confounders in regression analyses.ConclusionELAPE provides higher quality of LN harvests that meet the 12-minimal requirements than conventional APR, particularly in node-negative rectal cancers. The superiority is independent of potential confounding factors, and may implicate better clinical outcomes.

Oncological outcomes for transanal total mesorectal excision

: Total mesorectal excision (TME) has become the gold standard technique for rectal cancer surgery with curative intent. Advantages in technology and surgical innovation lead to the introduction of minimally invasive techniques including laparoscopic, robotic and, more recently, transanal TME (TaTME). The concept of TaTME has been proposed to overcome the technical challenges encountered with the transabdominal approaches (open, laparoscopic, robotic) in the most difficult cases (obese, male patients with mid-low rectal cancer and a narrow, radiated pelvis and bulky mesorectum). Additionally, it has been recently claimed that TaTME offers at least 3 oncological advantages: (I) a longer distal resection margin (DRM), (II) a decreased rate of positive circumferential resection margin (CRM), (III) improved quality of TME. However, the oncological outcomes of TaTME compared to those of laparoscopic and robotic TMEs, remain controversial. Hence, a review of all the literature examining oncological outcomes after TaTME was performed. Two reviewers independently conducted a search of electronic databases (PubMed, MEDLINE, Cochrane Library). The last search was performed on August, 30th 2019. After the initial screen of 326 articles, 32 papers were selected for review, of these 19 were comparative studies and 1 a randomized controlled trial. TaTME resulted to provide oncologic outcomes at least comparable with the other minimally invasive approaches (laparoscopic, robotic) and seems to be associated with a lower rate of CRM involvement and TME incompleteness when compared to the laparoscopic, robotic, open approaches. Scarcity of data and short follow-up time made it impossible to draw conclusions on long-term oncologic outcomes. Hopefully, the COLOR III multicenter RCTs will shed a light on short- and long-term oncologic outcomes after TaTME.

Can pathological reports of rectal cancer provide national quality indicators?

Rectal cancer care has become increasingly complex and requires accurate information. The pathology report is a vital tool for accessing information to gauge a patient's prognosis and to guide treatment decisions. The aim of this study was to assess the quality of histopathological reporting and surgery for rectal cancer in New Zealand using defined quality indicators. This is a retrospective audit of pathological reports of all resected rectal cancer pathology reports submitted to the New Zealand Cancer Registry (NZCR) in 2015. The quality of reporting was assessed using specified criteria: synoptic report, adequate lymph node retrieval, reporting of circumferential resection margin (CRM) and mesorectal excision quality. Surgical outcomes were sphincter preservation rate, CRM clearance and complete mesorectal excision. A total of 803 patients with rectal cancer were reported to the NZCR in 2015, 505 underwent proctectomy. A total of 89.5% of reports were structured, 81.8% reported mesorectal excision quality and 86.7% reported CRM status. Adequate lymph node retrieval was obtained in 65.1%, complete mesorectal excision in 84.6% and positive CRM in 6.2% of cases. Quality varied between laboratories and district health boards. High-volume laboratories had higher quality reporting. Surgeon volume and training was related to adequate lymph node retrieval but not CRM clearance nor mesorectal excision quality. High-quality pathological reporting is associated with the use of synoptic reporting templates. Surgical outcomes for rectal cancer in New Zealand, especially the low rate of CRM involvement, compare favourably with international audits.

Robot-assisted versus conventional laparoscopic operation in anus-preserving rectal cancer: a meta-analysis

ObjectiveThe aim of this meta-analysis is to provide recommendations for clinical practice and prevention of postoperative complications, such as circumferential resection margin (CRM) involvement, and compare the amount of intraoperative bleeding, safety, operative time, recovery, outcomes, and clinical significance of robot-assisted and conventional laparoscopic procedures in anus-preserving rectal cancer.MethodsA literature search (PubMed) was performed to identify biomedical research papers and abstracts of studies comparing robot-assisted and conventional laparoscopic procedures. We attempted to obtain the full-text link for papers published between 2000 and 2016, and hand-searched references for relevant literature. RevMan 5.3 software was used for the meta-analysis.ResultsNine papers (949 patients) were eligible for inclusion; there were 473 patients (49.8%) in the robotic group and 476 patients (50.2%) in the laparoscopic group. According to the data provided in the literature, seven indicators were used to complete the evaluation. The results of the meta-analysis suggested that robot-assisted procedure was associated with lower intraoperative blood loss (mean difference [MD] −41.15; 95% confidence interval [CI] −77.51, −4.79; P=0.03), lower open conversion rate (risk difference [RD] −0.05; 95% CI −0.09, −0.01; P=0.02), lower hospital stay (MD −1.07; 95% CI −1.80, −0.33; P=0.005), lower overall complication rate (odds ratio 0.58; 95% CI 0.41, 0.83; P=0.003), and longer operative time (MD 33.73; 95% CI 8.48, 58.99; P=0.009) compared with conventional laparoscopy. There were no differences in the rate of CRM involvement (RD −0.02; 95% CI −0.05, 0.01; P=0.23) and days to return of bowel function (MD −0.03; 95% CI −0.40, 0.34; P=0.89).ConclusionThe Da Vinci robot was superior to laparoscopy with respect to blood loss, open conversion, hospital stay, and postoperative complications during anus-preserving rectal cancer procedures; however, conventional laparoscopy had an advantage regarding operative time. The remaining indicators (CRMs and recovery from intestinal peristalsis) did not differ.

A pilot randomized study comparing extralevator with conventional abdominoperineal excision for low rectal cancer after neoadjuvant chemoradiation.

The aims of this study were to assess the feasibility of performing an extralevator abdominoperineal excision (ELAPE) after neoadjuvant chemoradiation (NCRT), to compare the rates of circumferential resection margin (CRM) involvement and intra-operative perforation (IOP) of the specimen, and to assess the amount of tissue removed around the muscularis propria (MP)/internal sphincter (IS) of the lower rectum in patients with low rectal cancer undergoing ELAPE compared with conventional abdominoperineal excision (CAPE) after NCRT. This was an open-label, parallel-arm pilot randomized trial conducted in India. Twenty patients were randomized to one of the study arms. The surgical specimens were fixed, serially cross-sectioned and photographed. Using specialized morphometry software, the amount of tissue resected with each operation was measured. There was a nonsignificant trend towards more IOPs (30% vs 0%, P=0.06) and a higher CRM involvement rate (40% vs 20%, P=0.32) in the CAPE arm. ELAPE removed a significantly greater amount of tissue around the IS/MP when compared with CAPE (mean±SD: 1911.39±382mm2 vs 1132.03±371mm2 , P<0.001). The mean distance from the IS/MP to the CRM was significantly greater in the ELAPE arm both in the posterior (mean±SD: 28.28±3mm vs 9.63±3mm, P<0.001) and lateral (mean±SD: 13.69±3mm vs 9.72±3mm, P=0.009) parts of the rectum but not in the anterior part (mean±SD: 6.74±2mm vs 6.10±4mm, P=0.64). The short-term morbidity was not significantly different between the two procedures. ELAPE removed more tissue in the lower rectum and resulted in a lower rate of IOP and CRM involvement when compared with CAPE, even after NCRT.

The meta analysis of pathological and long-term outcomes of laparoscopic vs. open surgery for rectal cancer.

e15039 Background: The non-inferiority of laparoscopic surgery (LS) for rectal cancer remains controversial. This study aimed to compare pathological and long-term outcomes of LS and open surgery (OS). Methods: We searched eligible randomized clinical trials (RCTs), published between Jan 1990 and Nov 2015, to compare LS and OS for rectal cancer. For dichotomous and continuous variables, the outcomes were summarized as odds ratios (ORs) and weighted mean differences (WMDs) respectively. The combined survival outcomes were expressed as hazard ratios (HRs). Subgroup analysis was conducted for patients underwent total mesorectal excision (TME). The PRISMA statement was complied. Results: Fifteen RCTs enrolling 4112 patients were included. The patients’ baseline characteristics of two groups were similar. The incomplete resection of mesorectal fascia was significantly more common in LS patients (OR, 1.49). There were no significant differences in circumferential resection margin (CRM) involvement, number of lymph nodes harvested, distal resection margin clearance. The TME subgroup analysis showed a higher rate of CRM involvement in LS group (OR, 1.56). The disease free survival and overall survival were equivalent. The inferior pathological results were led by the latest trials of ALaCaRT and ACOSOGZ6051, which had not reported the long-term results. Conclusions: This study demonstrated that laparoscopic rectal cancer resection related with the inferiority for pathological outcomes, especially in patients received TME. More long-term results of RCTs are mandatory to evaluate the safety of LS for rectal cancer. Meta-analysis results of pathological and long-term outcomes. Outcomes Overall Analysis Subgroup Analysis (TME) Number (LS/OS) OR, WMD or HR (95% CI) P Number (LS/OS) OR, WMD or HR (95% CI) P Incomplete Mesorectal Fascia 1348/989 1.49 (1.17,1.90) 0.001 682/ 658 1.52 (1.14,2.03) 0.004 CRM Involvement 1780/ 1377 1.22 (0.92,1.61) 0.17 840/ 818 1.56 (1.03,2.38) 0.04 Disease Free Survival 1348/880 0.94 (0.83,1.08) 0.39 343/ 338 0.97 (0.79,1.19) 0.78 Overall Survival 1517/ 1054 0.90 (0.80,1.02) 0.11 512/ 512 0.99 (0.84,1.16) 0.89 I 2 value of above outcomes were 0 % indicating no heterogeneity.

Short-term Outcomes of an Extralevator Abdominoperineal Resection in the Prone Position Compared With a Conventional Abdominoperineal Resection for Advanced Low Rectal Cancer: The Early Experience at a Single Institution.

PurposeThis study compared the perioperative and pathologic outcomes between an extralevator abdominoperineal resection (APR) in the prone position and a conventional APR.MethodsBetween September 2011 and March 2014, an extralevator APR in the prone position was performed on 13 patients with rectal cancer and a conventional APR on 26 such patients. Patients' demographics and perioperative and pathologic outcomes were obtained from the colorectal cancer database and electronic medical charts.ResultsAge and preoperative carcinoembryonic antigen (CEA) level were significantly different between the conventional and the extralevator APR in the prone position (median age, 65 years vs. 55 years [P = 0.001]; median preoperative CEA level, 4.94 ng/mL vs. 1.81 ng/mL [P = 0.011]). For perioperative outcomes, 1 (3.8%) intraoperative bowel perforation occurred in the conventional APR group and 2 (15.3%) in the extralevator APR group. In the conventional and extralevator APR groups, 12 (46.2%) and 6 patients (46.2%) had postoperative complications, and 8 (66.7%) and 2 patients (33.4%) had major complications (Clavien-Dindo III/IV), respectively. The circumferential resection margin involvement rate was higher in the extralevator APR group compared with the conventional APR group (3 of 13 [23.1%] vs. 3 of 26 [11.5%]).ConclusionThe extralevator APR in the prone position for patients with advanced low rectal cancer has no advantages in perioperative and pathologic outcomes over a conventional APR for such patients. However, through early experience with a new surgical technique, we identified various reasons for the lack of favorable outcomes and expect sufficient experience to produce better peri- or postoperative outcomes.

Extralevator Abdominoperineal Resection in the Prone Position.

See Article on Page 12-19 The conventional abdominoperineal resection (APR) has been the gold standard for the surgical treatment of low rectal cancer. Regardless of the approach, the APR represented a uniquely challenging procedure where the surgeon is expected to reduce the circumferential resection margin (CRM), local recurrence (LR) and wound complications. For cancer patients, excision of the anal canal with a wide circumferential margin, including a cylindrical cuff of the levator, muscle was introduced. As described by West et al. [1], compared with standard surgery, the extralevator APR (ELAPR) may reduce CRM involvement (from 49.6% to 20.3%, P < 0.001) and intraoperative perforation (IOP) (from 28.2% to 8.2%, P < 0.001), but with an increase in perineal wound complications (from 20% to 38.0%, P = 0.019). In contrast, they did not demonstrate the statistically differences in CRMs and wound complications between the groups. A metaanalysis study by De Nardi et al. [2] found significant differences in the CRM involvement rate (odds ratio [OR], 2.9; P < 0.001), intraoperative perforation (OR, 4.30; P < 0.001), local recurrence rate (OR, 2.52; P = 0.02), and length of hospital stay (OR, 1.06; P < 0.001) in favor of the ELAPR group. Additionally, perineal wound complications were higher in the extended group (OR, 0.62; P = 0.007). Yang et al. [3] reported that ELAPR had a lower rate of intraoperative perforation and local recurrence than APR in terms of short follow-up time. Yang et al. [4] reported better results in laparoscopic ELAPR: a 6.1% CRM rate, 15.2% morbidity, and no mortality. The perineal dissection can be performed in the lithotomy position or in the prone position after closure of the abdomen and creation of the colostomy. The author [5] reported that compared to the conventional APR, the ELAPR in the prone position did not have advantages in terms of perioperative complications and pathologic outcomes such as the CRM. In my opinion, the ELAPR in the prone position for treating patients with lower rectal or locally-recurrent pelvic cancer allows better exposure of the operative field and more precise perineal dissection according to the tissue plane and leaves open the possibility of an en-bloc combined resection of the sacrum or coccyx in difficult cases with sacral invasion. However, we need further randomized controlled studies to clearly identify the advantages and the disadvantages of the ELAPR in the prone position.

PWE-274 Robotic rectal cancer surgery offers significant benefits over the laparoscopic technique

Introduction Robotic surgery provides unique potential benefits when performing rectal surgery such as a stable 3D view and precision dissection with wristed instruments and improved access to the pelvis. Previous studies have reported equivalent outcomes to laparoscopic surgery but no benefit has yet been identified. We aimed to review our unselected cohort of rectal cancer resections. Method Analysis of a prospectively collected database was conducted covering a consecutive five-year period from 2009 to 2014. All patients were treated by one of two robotic surgeons and had a tumour within 15 cm of the anal verge and underwent either robotic or laparoscopic resection. The decision to offer robotic surgery was based on surgeon preference for the individual case and influenced by availability of the robot and in some cases the results of randomization in an international trial. For robotic resections a hybrid technique was employed with laparoscopic abdominal surgery followed by 4-arm robotic rectal mobilisation. Results 156 cases were analysed, 88 robotic and 68 laparoscopic, with a median follow up of 20 months. There was no significant difference between the groups in terms of gender, BMI, ASA classification, pathological staging or the use of pre-operative long-course chemo-radiotherapy. Robotic patients were significantly younger (65.7 yrs (SD 10.8) vs 69.7 yrs (SD 11.3); p = 0.029). Distance of the tumour from the anal verge was significantly shorter in the robotic group (height (7.7 cm (SD 3.7) vs. 9.2cm (SD 3.6); p = 0.01) and this was reflected in a greater number of abdomino-perineal resections in the robotic versus laparoscopic group (17.0% vs. 7.4% respectively). The rate of conversion to open surgery (defined as any part of the procedure performed open apart from specimen extraction and stapler anvil insertion) was significantly lower in the robotic (11.4%) versus laparoscopic group (39%), p = 0.004, and there was a non-significant trend towards a shorter length of stay in the robotic group (median (IQR): robotic 6(5–9.75) days vs. laparoscopic 7(4.25–11), p = 0.60). There were no significant differences in other short-term outcomes including operative mortality, readmission and circumferential resection margin involvement rates. Conclusion In this unselected group, robotic surgery for rectal cancer provided equivalent oncological outcomes to laparoscopic surgery and a significantly lower rate of conversion to open surgery, despite lower tumours being treated. There was no difference in short-term adverse events. There may be a benefit in terms of shorter hospital stay and the results of a major international trial are awaited to determine whether there are any potential quality of life benefits. Disclosure of interest None Declared.

PWE-303 The accuracy of magnetic resonance imaging in the management of rectal cancer – are we meeting the standard?

Introduction Magnetic Resonance Imaging (MRI) of the pelvis informs treatment strategy in rectal cancer. Complex multidisciplinary treatment plans are formulated on the basis of TNM status and proximity of the tumour to the circumferential resection margin (CRM). Previous studies 1 report a high degree of MRI accuracy. We sought to assess the regional performance of MRI assessment of CRM. Method A total of 150 consecutive patients with rectal cancer who underwent staging MRI were identified from a prospectively collected audit database comprising 6 units within Greater Glasgow and Clyde (West of Scotland Colorectal Cancer Managed Clinical Network) between April 2012 and March 2013. Pre-operative MRI prediction of circumferential resection margin (CRM) involvement was studied in both groups receiving neoadjuvant therapy and those proceeding directly to surgical resection. In all cases the MRI prediction of CRM was compared with final pathological assessment of CRM status. Patients who had metastatic disease at initial diagnosis, did not undergo MRI or did not proceed to surgical resection were excluded. Results Of 102 patients who underwent resection of rectal cancer (either APR or anterior resection) 74 patients proceeded directly to surgery and 28 underwent neoadjuvant chemoradiotherapy prior to resection. Four patients were found to have an involved CRM at final pathological analysis (4%) (2 in the group proceeding direct to resection and 2 in the neodjuvant therapy group). The specificity of MRI prediction of CRM involvement, in the direct-to-surgery cohort was 100% (95% CI 95–100), and negative predictive value (NPV) was 97% (95% CI 90–99). However in the group receiving neoadjuvant therapy prior to resection, the post-treatment MRI had a specificity of 53% (95% CI 33–73) and NPV of 100% (95% CI 76–100). Conclusion Pelvic MRI has become commonplace in the staging of rectal cancer. The prediction of CRM involvement is critical to complex decision making 2 about treatment modalities and in particular whether neoadjuvant therapy is instituted. Local institution of MRI assessment has resulted in a favourably low rate of CRM involvement at final pathology (4%). A high NPV allows selective use of neoadjuvant therapy for those at risk of an involved CRM. Disclosure of interest None Declared. References Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study. MERCURY Study Group. BMJ. 2006 Oct 14;333(7572):779 Multicenter Evaluation of Rectal cancer ReImaging pOst Neoadjuvant (MERRION) Therapy. Hanly AM, Ryan EM, Rogers AC, McNamara DA, Madoff RD, Winter DC; MERRION Study Group. Ann Surg . 2014. Apr;259(4):723–7. doi: 10.1097/SLA.0b013e31828f6c91. PMID:23744576

PWE-311 Extra-levator abdomino-perineal resection for low rectal cancer

Introduction Extra-levator abdomino-perineal resection (eLAP) has superseded standard abdomino-perineal excision (APER) for low rectal cancer. Reduction in rates of circumferential resection margin (CRM) involvement and tumour perforation offer improved oncological outcome. There is no consensus regarding management of the larger perineal defect that results. We report outcomes following primary closure following an eLAP. Method All eLAPs undertaken in a single centre over five years were identified. eLAP and primary closure is the local standard of care. A retrospective review recorded CRM involvement, primary wound healing and infection rates, the incidence of perineal herniae, and subsequent intervention if required. Results Fifty-one patients were identified, with a mean age of 70.2, and a male preponderance of 63%. Ten patients were classified ASA 3 (19.6%); the remainder were ASA 1–2. Thirty-two patients had a laparoscopic operation (63%), with a further 6 converted to open (12%). 14 patients had an open operation (27%). 38/51 patients (75%) had a clear CRM. There were no tumour perforations. EMVI was present in 13 patients (25%). Wound healing problems were identified in 12 patients (24%), with 6 requiring intervention (12%). The incidence of perineal hernia was 9/51 (18%) of which 5 (9.8%) were repaired surgically. Conclusion This series suggests that eLAP combined with primary closure of the perineum may offer the benefits of low rates of CRM involvement and tumour perforation yet minimal perineal wound related morbidity compared to published data. Disclosure of interest None Declared.

The role of the laparoscopy on circumferential resection margin positivity in patients with rectal cancer: long-term outcomes at a single high-volume institution.

The aim of this study was to evaluate the influence of laparoscopic rectal cancer surgery on circumferential resection margin (CRM) involvement. The data from 579 consecutive patients who underwent laparoscopic or open resection of rectal cancer from October 2002 to August 2008 were analyzed retrospectively. The primary endpoint was CRM status. The secondary endpoints were morbidity, local recurrence rate, overall survival, and disease-free survival. Laparoscopic resections were performed in 266 patients (46%), and the remainder of the patients underwent open resection. The rates of CRM involvement were similar between the laparoscopic and open groups (5.6% vs. 5.4%). The perioperative morbidity rates between the 2 groups were not significantly different (P=0.2). The incidence of local recurrence for the CRM-negative group was 8.4% (8.3% laparoscopic vs. 8.45% open; P=0.99), whereas the local recurrence rate was 34.3% for the CRM-positive group. The local recurrence rate was 20% for the CRM-positive patients in the laparoscopic group and 47% for the CRM-positive patients in the open group (P<0.001). We did not observe any significant differences in local recurrence rates between the Lap R and Open R groups after omitting CRM status. CRM positivity was correlated with both 5-year survival and the 5-year disease-free survival rate (P=0.009 and P=0.001, respectively). We did not observe any significant differences in morbidity, local recurrence, or overall or disease-free survival rates between the overall laparoscopic and open resection groups. Laparoscopic surgery for rectal cancer is associated with similar complication rates, CRM involvement status, and long-term outcomes as those associated with open surgery but with the advantages of minimally invasive surgery. Although laparoscopic surgery might necessitate more advanced technical skills, similar long-term oncological results can be obtained with this technique.

Meta-analysis of oncological outcome after abdominoperineal resection or low anterior resection for lower rectal cancer.

In lower rectal cancer, postoperative outcome is still subject of controversy between the advocates of abdominoperineal resection (APR) and low anterior resection (LAR). Reports suggest that low anterior resection may be oncologically superior to abdominoperineal excision, although no good evidence exists to support this. Publications were identified which assessed the differences comparing 5-year survival, local recurrence, circumferential resection margin rate, complications and so on. A meta-analysis was performed to clarify the safety and feasibility of the two procedures with several types of outcome measures. A total of 13 studies met the inclusion criteria, and comprised 6,850 cases. Analysis of these data showed that LAR group was highly correlated with 5-year survival (pooled OR = 1.73, 95%CI: 1.30–2.29, P = 0.0002 random-effect). And local recurrence rate of APR group was significantly higher than that in LAR group (pooled OR = 0.63, 95%CI: 0.53–0.75, P < 0.00001 fixed-effect). Also, the circumferential resection margin (CRM) were high involved in APR group than in LAR group. (5 trials reported the data, pooled OR = 0.43, 95%CI: 0.36–0.52, P < 0.00001 fixed-effect). Besides, the incidents of overall complications of APR group was higher compared with LAR group (pooled OR = 0.52, 95%CI: 0.29–0.92, P = 0.03 random-effect). Patients treated by APR have a higher rate of CRM involvement, a higher local recurrence, and poorer prognosis than LAR. And there is evidence that in selected low rectal cancer patients, LAR can be used safely with a better oncological outcome than APR. due to the inherent limitations of the present study, for example, the trails available for this systematic review are limited and the finite retrospective data, future prospective randomized controlled trials will be useful to fully investigate these outcome measures and to confirm this conclusion.

Permanent stoma rates: a misleading marker of quality in rectal cancer surgery

The latest National Bowel Cancer Audit Programme (NBOCAP) audit identified our colorectal unit as an outlier with regard to the high permanent stoma rate. The aim of this study was to perform an audit of the rationale for stoma formation in patients undergoing rectal cancer resection in our unit. A review was conducted of all rectal cancer operations between April 2011 and March 2013. Preoperative staging investigations and operation reports were reviewed to identify the reasons for nonrestorative surgery. Postoperative histology reports were used to identify circumferential resection margin (CRM) involvement and tumour height. One-hundred and twenty-five patients underwent surgery for rectal cancer, of whom 102 underwent elective resection with curative intent. The permanent stoma rate was 63.2% when emergency and palliative procedures were included and 54.9% when only elective curative cases were considered. Tertiary referrals made up 31.4% of elective cases. The main reasons for nonrestorative surgery included multivisceral resection (n = 24) for locally advanced cancer and operations for lesions close to the anal sphincter (n = 21). The median length of stay was 8 days, the 90-day mortality was 2.9% and the rate of CRM involvement was 2.0%. Our unit provides multivisceral surgery for locally advanced rectal cancer and receives a substantial number of tertiary referrals. Many of the rectal cancers referred are locally advanced or threaten the anal sphincter. This study demonstrates that the complexity of a unit's case-mix can have a profound effect on the permanent stoma rate. Stoma rates taken at face value do not therefore provide an accurate representation of surgical quality. What does this paper add to the literature? The study reviews the practice of a colorectal surgical unit with an interest in multivisceral surgery with regard to the permanent stoma rate. The reasons for nonrestorative surgery are analysed, and the problems associated with the use of stoma rates as a marker of quality in colorectal surgery are highlighted.

Oncological superiority of extralevator abdominoperineal resection over conventional abdominoperineal resection: a meta-analysis

The oncological superiority, i.e., lower circumferential resection margin (CRM) involvement, lower intraoperative perforation (IOP), and local recurrence (LR) rates, of extralevator abdominoperineal resection (EAPR) over conventional abdominoperineal resection (APR) for rectal cancer is inconclusive. This meta-analysis systematically compared the rates of CRM involvement, IOP, and LR of rectal cancer patients treated by EAPR and APR, respectively. An electronic literature search of MEDLINE, EMBASE, and Cochrane Library through May 2013 was performed by two investigators independently to identify studies evaluating the CRM involvement, IOP, and LR rates of EAPR and APR, and search results were cross-checked to reach a consensus. Data was extracted accordingly. A Mantel-Haenszel random effects model was used to calculate the odds ratio (OR) with 95 % confidence intervals (95 % CI). Six studies with a total of 881 patients were included. Meta-analysis of CRM involvement and IOP data from all six studies demonstrated significant lower CRM involvement (OR, 0.36; 95%CI, 0.23-0.58; P < 0.0001) and IOP (OR, 0.31; 95%CI, 0.12-0.80; P = 0.02) rates of EAPR. Data from four studies also showed that EAPR was associated with a lower LR rate than APR (OR, 0.27; 95%CI, 0.08-0.95; P = 0.04). No differences of between-study heterogeneity or publication bias were seen in any of the meta-analyses. Extralevator abdominoperineal resection could achieve better CRM involvement outcome and lower IOP and LR rates, demonstrating an oncological superiority over conventional abdominoperineal resection.

Systematic review and meta-analysis of the influence of circumferential resection margin involvement on survival in patients with operable oesophageal cancer

The prognostic role and definition of circumferential resection margin (CRM) involvement in operable oesophageal cancer remain controversial. The College of American Pathologists (CAP) and Royal College of Pathologists (RCP) define CRM involvement as tumour found at the cut resection margin and within 1 mm of the cut margin respectively. This systematic review and meta-analysis was performed to determine the influence of CRM involvement on survival in operable oesophageal cancer. PubMed, MEDLINE and the Cochrane Library (January 1990 to June 2012) were searched for studies correlating CRM involvement with 5-year mortality. Statistical analysis of dichotomous variables was performed using the odds ratio (OR) as the summary statistic. Fourteen studies involving 2433 patients with oesophageal cancer who had undergone potentially curative oesophagectomy were analysed. Rates of CRM involvement were 15·3 per cent (173 of 1133) and 36·5 per cent (889 of 2433) according to the CAP and RCP criteria respectively. Overall 5-year mortality rates were significantly higher in patients with CRM involvement compared with CRM-negative patients according to both CAP (OR 4·02, 95 per cent confidence interval (c.i.) 2·25 to 7·20; P < 0·001) and RCP (OR 2·52, 1·96 to 3·25; P < 0·001) criteria. CRM involvement between 0·1 and 1 mm was associated with a significantly higher 5-year mortality rate than CRM-negative status (involvement more than 1 mm from CRM) (OR 2·05, 95 per cent c.i. 1·41 to 2·99; P < 0·001). CRM involvement is an important predictor of poor prognosis. CAP criteria differentiate a higher-risk group than RCP criteria, but overlook a patient group with similar poor outcomes.