Negative Circumferential Margin Research Articles

442. POSTOPERATIVE ADJUVANT RADIOTHERAPY REDUCES LOCOREGIONAL RECURRENCE IN PATIENTS WITH BORDERLINE RESECTABLE ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Background borderline resectable esophageal squamous cell carcinoma (Br-ESCC) patients who underwent R0 resection had a significantly improved prognosis. However, local recurrence cannot be ignored. We sought to investigate the efficacy of postoperative adjuvant radiotherapy in reducing locoregional recurrence in patients with Br-ESCC. Methods we established a new resection status, Rbr+, which was defined as no clear boundary between the mass/scar and the outer aortic/tracheal membrane, no visible cancer remaining on the outer aortic/tracheal membrane, and a pathologically negative circumferential margin. patients with Br-ESCC who underwent curative esophagectomy at our center from January 2018 to December 2021 were eligible for this study. Patient characteristics, and perioperative variables were included in this study. univariable and multivariable analyses were performed to compare locoregional recurrence based on the logistic regression model. The Kaplan-Meier method and Cox proportional hazard model were used to compare overall and cause-specific survival. Results A total of 99 patients were included, among whom 27 (27.3%) had a locoregional recurrence. 71.7% (71/99) were classified as Rbr+ resection, and 28.3% (28/99) were classified as Rbr- resection. With a median postoperative follow-up of 55.3 months (range, 24.3-70.8 months), 25 patients out of 71 with Rbr+ resection suffered from local recurrence. However, 2 patients out of 28 with Rbr- resection suffered from locally recurrence. The locoregional recurrence was 25%(7/28) and 41.9%(18/43) in Rbr+ resection with and without postoperative adjuvant radiotherapy. While, the locoregional recurrence was 8.33%(1/12) and 6.25%(1/16) in Rbr- resection patients with and without postoperative adjuvant radiotherapy. Conclusion Rbr+ resection was independently associated with locoregional recurrence in patients with Br-ESCC. postoperative adjuvant radiotherapy was independently associated with overall and cause-specific survival in patients with Br-ESCC.

Circumferential resection margin rates in esophageal cancer resection- oncological equivalency and comparable clinical outcomes between open versus minimally invasive techniques: A retrospective cohort study.

Radical surgery for esophageal cancer requires macroscopic and microscopic clearance of all malignant tissue. A critical element of the procedure is achieving a negative circumferential margin (CRM) to minimize local recurrence. The utility of minimally invasive surgery poses challenges in replicating techniques developed in open surgery, particularly for hiatal dissection in esophago-gastrectomy. In this study, the technical approach and clinical and oncological outcomes for open and laparoscopic esophago-gastrectomy are described with particular reference to CRM involvement. This cohort study included all patients undergoing either open or laparoscopic esophago-gastrectomy between January 2004 to June 2022 in a single tertiary center. A standard surgical technique for hiatal dissection of the esophago-gastric junction developed in open surgery was adapted for a laparoscopic approach. Clinical parameters, length of stay (LOS), post-operative complications and mortality data were collected and analyzed by a Mann-Whitney U or Fisher's exact method. Overall 447 patients underwent an esophago-gastrectomy in the study with 219 open and 228 laparoscopic procedures. The CRM involvement was 18.8% in open surgery and 13.6% in laparoscopic surgery. The 90-day-mortality for open surgery was 4.1% compared with 2.2% for laparoscopic procedures. Median Intensive care unit (ITU), inpatient LOS and 30-day readmission rates were shorter for laparoscopic compared with open esophago-gastrectomy (ITU: 5 versus 8 days, P=0.0004; LOS: 14 versus 20 days, P=0.022; 30-day re-admission 7.46% versus 10.50%). Post-operative complication rates were comparable across both cohorts. The rates of starting adjuvant chemotherapy were 51.8% after open and 74.4% in laparoscopic esophago-gastrectomy. This study presents a standardized surgical approach to hiatal dissection for esophageal cancer. We present equivalence between open and laparoscopic esophago-gastrectomy in clinical, oncological and survival outcomes with similar rates of CRM involvement. We also observe a significantly shorter hospital length of stay with the minimally invasive approach.

Primary Surgery Followed by Selective Chemoradiotherapy Versus Preoperative Chemoradiotherapy Followed by Surgery for Locally Advanced Rectal Cancer: A Randomized Clinical Trial

The aim of this work was to determine whether locally advanced rectal cancer (LARC) with negative mesorectal fascia (MRF) predicted by magnetic resonance imaging (MRI) can be excluded from preoperative radiation therapy treatment. This multicenter, open-label, non-inferiority, randomized clinical trial enrolled patients with LARC within 6 to 12 cm from the anal verge and with negative MRI-predicted MRF. Participants were randomized to the intervention group (primary surgery, in which the patients with positive pathologic [CRM] circumferential margins were subjected to chemoradiotherapy [CRT] and those with negative CRM underwent adjuvant chemotherapy according to pathologic staging) or the control group (preoperative CRT, in which all patients underwent subsequent surgery and adjuvant chemotherapy). The primary endpoint was 3-year disease-free survival (DFS). A total of 275 patients were randomly assigned to the intervention (n = 140) and control (n = 135) groups, in which 33.57% and 28.15% patients were at clinical T4 stage and 85.92% and 80.45% patients were at "bad" or "ugly" risk in the intervention and control groups, respectively. There were 2 patients (1.52%) and 1 patient (0.77%) with positive CRM in the intervention and control groups, respectively (P > .05). The non-adherence rates for the intervention and control groups were 3.6% and 23.7%, respectively. After a median follow-up of 34.6 months (IQR, 18.2-45.7), 43 patients had positive events (28 patients and 15 patients in the intervention and control groups, respectively). There were 6 patients (4.4%) with local recurrence in the intervention group and none in the control group, which led to the termination of the trial. The 3-year DFS rate was 81.82% in the intervention group (95% CI, 78.18%-85.46%) and 85.37% in the control group (95% CI, 81.75%-88.99%), with a difference of -3.55% (95% CI, -3.71% to -3.39%; hazard ratio, 1.76; 95% CI, 0.94-3.30). In the per-protocol data set, the difference between 3-year DFS rates was -5.44% (95% CI, -5.63% to -5.25%; hazard ratio, 2.02; 95% CI, 1.01-4.06). Based on the outcomes of this trial, in patients with LARC and MRI-negative MRF, primary surgery could negatively influence their DFS rates. Therefore, primary surgery was an inferior strategy compared with preoperative CRT followed by surgery and cannot be recommended for patients with LARC.

A Case of Synchronous Rectal Cancer and Right Sided Colon Cancer Treated with Transvaginal NOSES Technique

Introduction: We reported a 53 years old female patient with synchronous rectal cancer and right sided colon cancer who underwent transvaginal NOSES to resect two tumors with no serious postoperative complications. Case report: The patient underwent electronic colonoscopy and found two lesions in the intestine, located in the right colon and rectum. Pathological examination confirmed that both lesions were malignant tumors, and the patient was diagnosed with concurrent colon and rectal cancer. After diagnosis, the patient underwent transvaginal NOSES, and the intraoperative exploration results were consistent with electronic colonoscopy. The surgery completely resected two malignant tumors at same time. The pathological report staging of right colon cancer is AJCC stage II (pT3N0M0), with moderately differentiated adenocarcinoma and negative circumferential margin. The pathological report staging of rectal ancer is AJCC stage IIIpT2N1aM0), with moderately differentiated adenocarcinoma and negative circumferential margin. The patient recovered well after surgery and did not experience any serious postoperative complications. Patient receives XELOX chemotherapy after surgery. Discussion: Transvaginal NOSES is a safe and effective surgical method for synchronous multiple primary colorectal cancer. However, due to the complexity of the surgery and the increased anesthesia risks associated with additional surgical time, experienced surgical and anesthesia teams are required. Conclusion: The application of transvaginal NOSES in the treatment of synchronous multiple primary colorectal cancer is still in the exploratory stage, and more clinical studies are needed to prove its feasibility, safety, and effectiveness.

Patterns of Care and Outcomes of Rectal Cancer Patients from the Iowa Cancer Registry: Role of Hospital Volume and Tumor Location

BackgroundCentralization of rectal cancer surgery has been associated with high-quality oncologic care. However, several patient, disease and system-related factors can impact where patients receive care. We hypothesized that patients with low rectal tumors would undergo treatment at high-volume centers and would be more likely to receive guideline-based multidisciplinary treatment. MethodsAdults who underwent proctectomy for stage II/III rectal cancer were included from the Iowa Cancer Registry and supplemented with tumor location data. Multinomial logistic regression was employed to analyze factors associated with receiving care in high-volume hospital, while logistic regression for those associated with ≥ 12 lymph node yield, pre-operative chemoradiation and sphincter-preserving surgery. ResultsOf 414 patients, 38%, 39%, and 22% had low, mid, and high rectal cancers, respectively. Thirty-two percent were > 65 years, 38% female, and 68% had stage III tumors. Older age and rural residence, but not tumor location, were associated with surgical treatment in low-volume hospitals. Higher tumor location, high-volume, and NCI-designated hospitals had higher nodal yield (≥ 12). Hospital-volume was not associated with neoadjuvant chemoradiation rates or circumferential resection margin status. Sphincter-sparing surgery was independently associated with high tumor location, female sex, and stage III cancer, but not hospital volume. ConclusionsLow tumor location was not associated with care in high-volume hospitals. High-volume and NCI-designated hospitals had higher nodal yields, but not significantly higher neoadjuvant chemoradiation, negative circumferential margin, or sphincter preservation rates. Therefore, providing educational/quality improvement support in lower volume centers may be more pragmatic than attempting to centralize rectal cancer care among high-volume centers.

Outcomes of Robot-Assisted Surgery in Rectal Cancer Compared with Open and Laparoscopic Surgery.

With increasing trends for the adoption of robotic surgery, many centers are considering changing their practices from open or laparoscopic to robot-assisted surgery for rectal cancer. We compared the outcomes of robot-assisted rectal resection with those of open and laparoscopic surgery. We searched Medline, Web of Science, and CENTRAL databases until October 2022. All randomized controlled trials (RCTs) and prospective studies comparing robotic surgery with open or laparoscopic rectal resection were included. Fifteen RCTs and 11 prospective studies involving 6922 patients were included. The meta-analysis revealed that robotic surgery has lower blood loss, less surgical site infection, shorter hospital stays, and higher negative resection margins than open resection. Robotic surgery also has lower conversion rates, lower blood loss, lower rates of reoperation, and higher negative circumferential margins than laparoscopic surgery. Robotic surgery had longer operation times and higher costs than open and laparoscopic surgery. There were no differences in other complications, mortality, and survival between robotic surgery and the open or laparoscopic approach. However, heterogeneity between studies was moderate to high in some analyses. The robotic approach can be the method of choice for centers planning to change from open to minimally invasive rectal surgery. The higher costs of robotic surgery should be considered as a substitute for laparoscopic surgery (PROSPERO: CRD42022381468).

New trends in criteria indicative of neoadjuvant oncological therapy of lower and middle rectal cancers.

The indication for primary surgical resection or neoadjuvant therapy in lower and middle rectal cancers is often disputable. The aim of the study was to evaluate the occurrence of local recurrence of rectal cancer as for aperiod of at least 4 years after radical resection. The second aim was to evaluate and compare the results of preoperative magnetic resonance (MR) staging with definitive histology.From September 2013 to December 2017, we, at the 3rd Surgical Department Comenius University, Bratislava, prospectively evaluated patients with lower and middle rectal cancers with the distal tumor border being in a12-cm distance from the anal verge. All patients underwent MR examination at the same MRI department and were operated on at the 3rd Surgical Department, Comenius University, Bratislava. Inclusion criteria included parameters based on MRI examination, i.e., T-staging of T1-T3b, negative extramural vascular infiltration (EMVI), negative circumferential margin (CRM), no mesorectal fascia infiltration with a distance of more than 2 mm. We did not take lymph node staging into account in the indication for primary surgical resection. We performed a radical primary resection procedure (R0 resection) in all patients. The group consisted of 87 patients, of whom 49 were men and 38 were women. The mean age of the patients was 66 years (min. 36 - max. 86 years). Our study also shows significant differences in preoperative T and N staging as compared to definitive histology. The incidence of local recurrence during aperiod of at least 4 years after surgery was 6.76 %. Study also shows that the indication for preoperative radiotherapy for lower and middle rectal cancers based on N status is inaccurate and leads to unnecessary indications for preoperative radiotherapy which may decrease the patients´ quality of life and increase the post‑operative complications. We have also shown that leaving out the N-based radiotherapy from indications does not lead to an increase in the number of local recurrences in lower and middle rectal cancers (Tab. 1, Fig. 5, Ref. 22). Text in PDF www.elis.sk Keywords: rectal cancer, neoadjuvant therapy, local recurrence.

OGC P46 Positive Circumferential margins are associated with poorer survival following surgery in gastro-oesophageal junctional cancers

Abstract Background Adenocarcinoma of the gastro-oesophageal junction (GOJ) remains a significant clinical problem that is increasing in incidence and is associated with a poor prognosis. The aim of this study is to determine the effects of the resection margins on survival and recurrence. Methods A retrospective study was conducted at our hospital from March 2001 till December 2022. All the patients that had oesophagectomy for gastro-oesophageal junctional (GOJ) adenocarcinoma were included in this study. Demography, staging, margins, type of neo-adjuvant chemotherapy and survival data were collected. Results Over the study, 174 patients had Gastro-oesophageal junctional adenocarcinoma. 42 of the patients had circumferential margins positive and 132 had negative circumferential margins. The median for survival is 18 months in circumferential margins positive and 31 months for the circumferential negative patients with a P value of <0.001 There were no patients with longitudinal margins positive enough to calculate any statical analysis The median of recurrence is 13.4 months for the circumferential margins positive and 26.8 months for the circumferential margins negative patients with a P value on 0.003 Conclusions The presence of any circumferential margin tumour will significantly affect the survival rate and recurrence rate.

Primary surgery followed by selective radiochemotherapy versus conventional preoperative radiochemotherapy for patients with locally advanced rectal cancer with MRI-negative circumferential margin (PSSR): A multicenter, randomized, open-label, noninferiority, phase 3 trial.

3515 Background: Neoadjuvant radiochemotherapy is the standard treatment for locally advanced rectal cancer. However, radiation therapy can lead to bowel, urinary and sexual dysfunction. The study aims to clarify whether locally advanced rectal cancer with a distance of 6 to 12 cm from the anus with negative circumferential margins (CRM) predicted by MRI can be exempted from preoperative radiotherapy. Methods: PSSR (NCT02121405), a multicentre, randomized, open-label, non-inferiority, phase 3 trial, was done across 10 hospitals in China. Patients aged from 18 to 75 years with locally advanced rectal cancer (including all cT3/4 and/or Nany) with negative MRI-predicted CRM and tumor distance of 6 to 12 cm from anus were randomly assigned (1:1), by central randomization, to intervention group (surgery directly, in which positive CRM was supplemented with chemoradiotherapy, negative CRM received adjuvant chemotherapy according to surgical pathologic staging), or control group (neoadjuvant chemoradiotherapy then underwent surgery and adjuvant chemotherapy). The primary endpoint is the rate of 3-year disease-free survival (DFS). A sample size of 350 was set according to the original non-inferiority margin of 15% for the difference of rates for 3-year DFS, which was changed to 5% under the Data Safety Monitoring Board (DSMB) suggestion after an interim analysis. The efficacy analysis followed the per-protocol (PP) principle. Results: From December 2015 to February 2021, 299 patients were recruited. DSMB stopped this trial due to the difference of 3-year DFS’s rate between two groups more than 5% at the interim analysis in July 2021. A total of 275 were included for the final analysis. Based on the PP dataset, 238 patients followed the original protocol (135 patients in the intervention group and 103 patients in the control group). Patients who had positive CRM were 2(1.5%) and 1(1.0%) in two groups, respectively ( P= 1.00). After a median follow-up of 34.6 (IQR: 18.2-45.7) months, a total of 42 patients had positive events (30 patients in the intervention group and 12 patients in the control group). There were 5 (3.7%) patients with local recurrence in the intervention group ( P= 0.062). Patients with pathological complete response (pCR) and near pCR were 19 (18.4%) and 21 (20.4%) in the control group. The rate of 3-year DFS was 81.1% (77.3%-84.9%) (HR = 2.02, 95%CI: 1.01-4.06, P= 0.048) in the intervention group and 86.6% (82.7%-90.5%) in the control group, with difference of 5.4% (5.3%-5.6%), which did not meet the criteria for non-inferiority. Conclusions: In terms of DFS, initial surgery was inferior to conventional preoperative radiochemotherapy for locally advanced middle rectal cancer with MRI negative circumferential margin. Clinical trial information: NCT02121405.

Surgical management of splenic flexure colon cancer: a retrospective propensity-matched study comparing open and minimally invasive approaches using the national cancer database

Minimally invasive resection of colon cancer at the splenic flexure can be technically challenging with concerns for a suboptimal oncologic outcome. We aimed to compare open and minimally invasive approaches following curative resection. The National Cancer Database was queried for patients with non-metastatic colon adenocarcinoma at the splenic flexure who underwent resection from 2010 to 2016. Cohorts were separated into open and minimally invasive approaches, and demographic and clinicopathologic variables were compared. Propensity-score matching (PSM) was utilized to balance potential confounding covariates between cohorts to elucidate the independent association between surgical approach and outcomes. Kaplan-Meier estimation and Cox-proportional hazards regression were used to analyze survival. Secondary outcomes were analyzed by way of logistic regression or Mann-Whitney U test. After matching, 842 patients were compared between approaches. Patients who underwent minimally invasive surgery had no significant difference in regional nodes ≥ 12 examined, positive margins, negative circumferential margins, unplanned 30-day readmission, or time from surgery to initiation of chemotherapy when compared to patients who underwent open surgery. Minimally invasive surgery was significantly associated with decreased odds of 30-day mortality, 90-day mortality, and decreased mortality hazard for 5-year overall survival compared to open surgery. The optimal approach for surgical management of splenic flexure colon cancer has not been standardized given its rarity and exclusion from randomized controlled trials. Our retrospective review suggests that minimally invasive resection of splenic flexure colon cancers in carefully selected patients is associated with equivalent oncologic outcomes as well as improved short and long-term survival compared to an open approach.

Association of Transanal Total Mesorectal Excision With Local Recurrence of Rectal Cancer

Proponents of novel transanal total mesorectal excision (TME) suggest the procedure overcomes the technical and oncologic challenges of conventional approaches for treating rectal cancer. Recently, however, there has been controversy regarding the oncologic safety of the procedure. To assess the association of transanal TME with the incidence of local recurrence (LR) of cancer and the probability of remaining free of LR during follow-up. This multicenter cohort study used data from 8 high-volume rectal cancer academic institutions from across Canada on all consecutive patients with primary rectal cancer treated by transanal TME at the participating centers. The study was conducted between January 2014 and December 2018, and data were analyzed from April 1, 2020, to September 15, 2020. Transanal TME. The incidence of LR was reported as a direct measure of quality of resection. The cumulative probability of LR- and systemic recurrence (SR)-free survival at 36 months was estimated. Local recurrence and SR were defined as radiologic or endoscopic evidence of 1 or more new lesions in or outside the pelvis, respectively, documented during surveillance after the removal of the primary tumor. Of 608 total patients included in the analysis, 423 (69.6%) were male; the median age was 63 years (interquartile range [IQR], 54-70 years). Local recurrence was identified in 22 patients (3.6%) after a median follow-up of 27 months (IQR, 18-38 months). The median time to LR was 13 months (IQR, 9-19 months). Sixteen of the 22 patients with LR (72.7%) were male, 14 (63.6%) received neoadjuvant chemoradiation, and 12 (54.5%) had American Joint Committee on Cancer stage III disease. Of those with LR, 16 (72.7%) had a negative circumferential radial margin and 20 (90.9%) had a negative distal resection margin, 2 (9.1%) experienced conversion to open surgery, and 15 (68.2%) also developed SR. The probability of LR-free survival at 36 months was 96% (95% CI, 94%-98%). According to the Cox proportional hazards regression model, the hazard ratio of LR was estimated to be 4.2 (95% CI, 2.9-6.2) times higher among patients with a positive circumferential radial margin than among those with a negative circumferential radial margin. In this cohort study, transanal TME performed by experienced surgeons was associated with an incidence of LR and SR that is in line with the published literature on open and laparoscopic TME, suggesting that transanal TME may be an acceptable approach for management of rectal cancer.

Impact of Preoperative Care for Rectal Adenocarcinoma on Pathologic Specimen Quality and Postoperative Morbidity: A NSQIP Analysis

Comprehensive and multidisciplinary care are critical in rectal cancer treatment. We sought to determine if completeness of preoperative care was associated with pathologic specimen quality and postoperative morbidity. Clinical stage I-III rectal adenocarcinoma patients who underwent elective low anterior resection or abdominoperineal resection were identified from the 2016-2017 American College of Surgeons-National Surgical Quality Improvement Project (ACS-NSQIP) database. The 3 preoperative NSQIP variables (colonoscopy, stoma marking, and neoadjuvant chemoradiation) were used to divide patients into 2 cohorts: complete vs incomplete preoperative care. The primary outcome was a composite higher pathologic specimen quality score (>12 lymph nodes, negative circumferential, and negative distal margins). The secondary outcome was 30-day morbidity. Preoperative characteristics were compared with ANOVAs and chi-square tests. Outcomes measures were evaluated with logistic regression. We identified 1,125 patients: 591 (52.5%) complete and 534 (47.5%) incomplete. The complete group was younger, had more women, lower-third rectal tumors, clinical stage III disease, and neoadjuvant treatment. The complete group had higher odds of better pathologic specimen quality after adjusting for age, sex, tumor location, stage, and neoadjuvant therapy (adjusted odds ratio [aOR] 1.75, p= 0.001). The complete group had decreased rates of transfusions (odds ratio [OR] 0.47, p < 0.001), postoperative ileus (OR 0.67, p= 0.01), sepsis (OR 0.32, p= 0.01), and readmissions (OR 0.60, p= 0.003). Other complications did not statistically differ between groups. Complete preoperative care in rectal adenocarcinoma is associated with higher pathologic specimen quality and reduced postoperative morbidity. This highlights the importance of adherence to guideline-directed care.

Clinicopathological factors associated with positive circumferential margins in rectal cancers

Positive circumferential resections are associated with local disease recurrence and reduced survival in rectal cancer. We studied a cohort of consecutive rectal cancer resections to assess for clinicopathological differences and survival in patients with positive and negative circumferential margins. Rectal cancers were identified from a retrospective histopathology database of colorectal resections performed at five western Sydney hospitals from 2010 to 2016. Univariate and multivariate analysis with binary logistic regression were performed on histopathology data matched with survival times from the New South Wales Registry of Births Deaths and Marriages. A total of 502 rectal cancer patients were identified including 66 (13.1%) with involved circumferential margins. Patients with positive and negative circumferential margins had a similar distribution of age, gender and use of neoadjuvant radiotherapy. Tumours with involved circumferential margin comprised 98.5% T3 and T4 disease of which 51.5% received neoadjuvant radiotherapy. These were significantly associated with metastatic disease, increasing tumour size, circumferential and perforated tumours on univariate analysis. Multivariate analysis identified abdomino-perineal resection (odds ratio (OR) 3.35; P = 0.003), en-bloc multivisceral resection (OR 2.56; P = 0.032), T4 stage (OR 6.99; P < 0.001), perineural (OR 5.61; P < 0.001) and vascular invasion (OR 2.46; P = 0.022) as independent risk factors. Five-year survival was significantly worse for patients with involved circumferential margins (26% versus 69%; P < 0.001). Circumferential margin status reflects not only technical success but also aggressive disease phenotypes which require adjuvant therapy. Further work is needed to determine whether omission of radiotherapy has had an effect on long-term outcomes in some of our at-risk patients.

Long-term efficacy of pure transanal total mesorectal excision for middle-low rectal cancer

Objective To investigate the long-term efficacy of pure transanal total mesorectal excision (PtaTME) for middle-low rectal cancer. Methods The retrospective descriptive study was conducted. The clinicopathological data of 18 patients with middle-low rectal cancer who were admitted to the Sixth Affiliated Hospital of Sun Yat-sen University from July 2014 to August 2016 were collected. There were 7 males and 11 females, aged (58±13) years, with a range from 40 to 84 years. The body mass index was (22±3)kg/m2. All the 18 patients underwent PtaTME. Observation indicators: (1) surgical and postoperative conditions; (2) postoperative pathological examination; (3) follow-up and survival. Follow-up using inpatient reexamination, outpatient examination, and telephone interview were performed to detect anastomotic complications, anal function, urinary retention, sexual dysfunction, survival and tumor recurrence and metastasis once every 3 months within postoperative 6 months, once every 6 months from 6 months to 3 years, and once a year after 3 years up to June 2019. The measurement data with normal distribution were represented as Mean±SD, and the measurement data with skewed distribution were represented as M (range). Count data were expressed as percentages. Survival rates were calculated by the Kaplan-Meier method. Results (1) Surgical and postoperative conditions: 18 patients successfully underwent PtaTME, without conversion to open surgery. The operation time, volume of intraoperative blood loss, distance between anastomosis and anal verge, time to first flatus, time to urinary catheter removal, and duration of postoperative hospital stay were (202±68)minutes, 50 mL (range, 20-400 mL), (4.5±2.0)cm, 2 days (range, 2-7 days), 3 days (range, 2-5 days), and 7 days (range, 5-10 days) in the 18 patients, respectively. There was no perioperative complication. Among 18 patients, 4 underwent preventive ileostomy. (2) Postoperative pathological examinations: the length of surgical specimens, the number of lymph node dissection, distance from tumor to the distal margin were (11.0±3.0)cm, 12±6, and 1.0 cm (range, 0.8-3.7 cm), respectively. The 18 patients had complete mesorectal membrane excision, with negative proximal margin, distal margin, and circumferential margin. Tumor pathological staging: there were 2 cases in Tis stage, 4 in T1 stage, 7 in T2 stage, and 5 in T3 stage; 16 in N0 stage, 1 in N1 stage, and 1 in N2 stage. Tumor histological classification: 2 patients had carcinoma in situ, 9 had moderately differentiated adenocarcinoma, and 7 had high-differentiated adenocarcinoma. (3) Follow-up and survival: 18 patients were followed up for 34.0-59.0 months, with a median follow-up time of 57.5 months. During the follow-up, 4 patients developed grade B anastomotic leakage and were cured after conservative treatment. One patient developed anastomotic recurrence at 2 years after surgery, and no recurrence was found after surgical resection of the recurrent lesion. Four patients with prophylactic ileostomy had the stoma closured, and the anus function was satisfactory after surgery. There was no urinary retention or sexual dysfunction in the 18 patients. Of the 18 patients, 17 had tumor free survival after surgery. The 3-year disease-free survival rate was 94.4%, and the 3-year overall survival rate was 100.0% in 18 patients. Conclusion PtaTME can achieve high quality of specimen, which is safe and feasible for the treatment of rectal cancer. Key words: Rectal neoplasms; Rectal cancer; Total mesorectal excision; Pure transanal total mesorectal excision; Long-term efficacy

Minimally Invasive Surgery for Rectal Adenocarcinoma Shows Promising Outcomes Compared to Laparotomy, a National Cancer Database Observational Analysis

The surgical approach to adenocarcinoma of the rectum remains a controversial topic. Although current data focus on the noninferiority of minimally invasive surgery (MIS) for rectal cancer compared with laparotomy, conclusions are drawn from smaller sample sizes and may be underpowered. Methods/Interventions: The National Cancer Database (NCDB) from 2010 to 2014 was reviewed for all cases of invasive adenocarcinoma of the rectum (SEER Histology Codes 8140) who underwent surgical resection for malignancy. Groups were separated based on laparotomy or an MIS approach and stratified by NCDB Analytic Stage. Multivariate Cox regression analysis was used to evaluate for survival after diagnosis of adenocarcinoma of the rectum. Results/Outcomes: The inclusion criteria identified 29,199 cases of adenocarcinoma of the rectum managed surgically. After controlling for differences in the cohorts, survival after diagnosis and definitive surgical treatment for adenocarcinoma of the rectum is improved when an MIS approach was used (adjusted hazard ratio [HR] = 0.82, 95% confidence interval [CI] = 0.77-0.88, P < .001). The protective effect of an MIS approach applied to Stages I, II, III, and IV adenocarcinoma of the rectum. The protective effect of a minimally invasive surgical approach applies to Stages I, II, III, and IV adenocarcinoma of the rectum. The rate of negative circumferential margins (86.2% versus 83.5%, P < .001), proximal and distal margins (94.7% versus 92.1%, P < .001), and lymph node yield >12 (73.2% versus 70.1%, P < .001) was higher in the minimally invasive group compared with laparotomy. The intraoperative conversion rate from MIS to laparotomy was 13.9%. Minimally invasive resection for adenocarcinoma of the rectum shows promising survival benefit compared with open surgery after adjusting for measured confounds.

Transanal Total Mesorectal Excision (taTME) for Rectal Cancer: A Case Series Report of a Natural Orifice Surgical Technique

In the treatment of colorectal cancer, total mesorectal excision (TME) has risen as the gold standard in the surgical treatment of this disease in order to obtain negative distal and circumferential radial margins. Since introduction in 2010, transanal TME has aimed to decrease the rate of positive margins and improve the quality of the dissection while decreasing the complications associated with a transabdominal low pelvic dissection. We retrospectively reviewed 25 cases of transanal TME completed between December 2014 and August 2017. Most of the patients in our case series were male (60%) with an average age of 57.1 years, BMI of 28.4 kg/m², and with an American Society of Anesthesiologists score of II. The average tumor was midrectal (about 5.9 cm from the anal verge), clinically T3-T4 (92%), and had undergone neoadjuvant therapy (96%). The average operation was about six hours and 44 minutes with ileostomy placed most of the time (92%). In all the cases where the TME quality was graded, the specimens were reported to have been complete (grade I). There were no positive distal, radial, or proximal margins. The average hospital stay was about 5.9 days. The rate of minor complications was about 48 per cent and major complications occurred about 16 per cent of the time.

Single-Docking Full Robotic Surgery for Rectal Cancer: A Single-Center Experience.

Robotic surgery has gradually gained importance in the treatment of rectal cancer. However, recent studies have not shown any advantages when compared with laparoscopy. The objective of this study is to report a single surgeon's experience in robotic rectal surgery focusing on short-term and long-term outcomes. Sixty consecutive robotic rectal resections for adenocarcinoma, over a 4-year period, were retrospectively reviewed. Patients' characteristics and perioperative outcomes were analyzed. Oncological outcomes and surgical resection quality as well as overall and disease-free survival were also assessed. Thirty patients out of 60 (50%) underwent neoadjuvant therapy. Anterior rectal resection was performed in 52 cases (86.7%), and abdominoperineal resection was done in 8 cases (13.3%). Mean operative time was 283 (±68.6) minutes. The conversion rate was 5% (3 patients). Postoperative complications occurred in 10 cases (16.7%), and reoperation was required in 1 case (1.7%). Mean hospital stay was 9 days, while 30-day mortality was 1.7% (1 patients). The histopathological analysis reported a negative circumferential radial margin and distal margins in 100% of cases with a complete or near complete total mesorectal excision in 98.3% of patients. Mean follow-up was 32.8 months with a recurrence rate of 3.4% (2 patients). Overall survival and disease-free survival were 94% and 87%, respectively. Robotic surgery for rectal cancer proves to be safe and feasible when performed by highly skilled surgeons. It offers acceptable perioperative outcomes with a conversion rate notably lower than with the laparoscopic approach. Adequate pathological results and long-term oncological outcomes were also obtained.

A New Prediction Model for Local Recurrence After Curative Rectal Cancer Surgery: Development and Validation as an Asian Collaborative Study.

Local recurrence is one of the remaining problems in rectal and rectosigmoid cancer, and it is sometimes difficult to treat. This study aimed to explore various factors that are highly related to local recurrence and to develop a new prediction model for local recurrence after curative resection. This is a retrospective cohort study SETTINGS:: This study was conducted at 2 academic hospitals in Japan and Korea. A total of 2237 patients with stage I to III rectal and rectosigmoid cancer who underwent a curative operation with a negative circumferential margin were selected. Surgical treatment was the intervention. Local recurrence was the primary outcome measure. A total of 1232 patients were selected, and rectosigmoid cancer with rare local recurrence (2/221) was excluded. A different set of 792 patients with rectal cancer were chosen for validation. Multivariate analysis showed the following factors as significant for local recurrence: poorly differentiated tumor (HR, 11.2; 95% CI, 4.5-28.0), tumor depth (HR, 5.0), lymph node metastasis (HR, 4.1), operative procedure (HR, 3.2), postoperative complications (HR, 2.9), tumor location (HR, 2.6), and CEA level (HR, 2.4); a new prediction score was created by using these factors. A poorly differentiated tumor was assigned 2 points, and all other factors were assigned 1 point each. Patients who scored more than 5 points (n = 21) were judged as "high risk," with a 2-year local recurrence rate of 66.5%. The new predictive model could also separate the patients into different risk groups in the validation set. The high-risk group had higher recurrence rates than medium- and low-risk groups (2-year local recurrence rate: 41%, 15%, and 2.1%). This study was limited by its retrospective nature and potential for selection bias. Seven factors were shown to be significantly correlated with the local recurrence of rectal cancer, and the usefulness of this new prediction model was demonstrated. See Video Abstract at http://links.lww.com/DCR/A429.

Meta-analysis of the impact of surgical approach on the grade of mesorectal excision in rectal cancer

The subspecialization of colorectal surgeons, and improvements in the quality of mesorectal excision have revolutionized rectal cancer surgery. With the increasing use of minimally invasive techniques, the completeness of the mesorectal excision has been questioned. This study aimed to assess the pathological outcomes of open versus laparoscopic rectal resection. A meta-analysis of RCTs was undertaken. The primary endpoint was the adequacy of the mesorectal excision. Secondary endpoints included circumferential resection margin and distance to resection margins. Four studies were included, reporting on 2319 patients; 972 (41·9 per cent) had open and 1347 (58·1 per cent) had laparoscopic resections. Meta-analysis of adequacy of the mesorectal excision showed a small difference in achieving an intact mesorectum in favour of open surgery (risk ratio (RR) 1·06, 95 per cent c.i. 1·02 to 1·10; P = 0·001). Superficial defects were more common in laparoscopic surgery (RR 0·70, 0·54 to 0·89; P = 0·004). Deep mesorectal defects (RR 0·78, 0·51 to 1·20; P = 0·256), circumferential margin (CRM) positivity (RR 0·85, 0·62 to 1·16; P = 0·310), and distance to radial (mean difference (MD) -0·06, 95 per cent c.i. -0·10 to 0·23; P = 0·443) and distal (MD 0·03, -0·06 to 0·12; P = 0·497) margins were all similar. A complete resection (intact mesorectum, negative CRM and distal margin) was achieved in 350 of 478 patients (73·2 per cent) in the laparoscopic group and 372 of 457 (81·4 per cent) in the open group (risk difference (RD) 8 (95 per cent c.i. 3 to 13) per cent; P = 0·003). However, an acceptable mesorectum (intact or superficial defects only) was present in 1254 of 1308 (95·9 per cent) and 916 of 949 (96·5 per cent) in the laparoscopic and open groups respectively (RD 1 (-1 to 3) per cent; P = 0·263). Small differences in mesorectal quality were evident between open and laparoscopic rectal resections. This may be attributable to use of laparoscopic instruments; however, to date minor defects have not affected oncological outcomes.

Clinical efficacy of single-port Da Vinci robotic surgical system in the radical resection of rectal cancer

Objective To explore the clinical efficacy of single-port Da Vinci robotic surgical system in the radical resection of rectal cancer. Methods The retrospective descriptive study was conducted. The clinical data of one patient with rectal cancer who was admitted to the Southwest Hospital of the Third Military Medical University in June 2017 was collected. The patient underwent the first case of radical resection of rectal cancer with the single-port Da Vinci robotic surgical system, and intraoperatively received laparoscopy-assisted digestive tract reconstruction. Observation indicators: (1) intra- and post-operative situations; (2) follow-up and survival. Follow-up using outpatient examination and telephone interview was performed to detect patients′ survival up to July 2017. Results (1) Intra- and post-operative situations: the patient underwent successful single-port Da Vinci robotic radical resection of rectal cancer. The operation time and volume of intraoperative blood loss were 145 minutes and 20 mL, without blood transfusion. The using time of nonsteroidal analgesic drug, time for out-of-bed activity, time to anal exsufflation, time of fluid diet intake and time of pelvic drainage tube removal were 1 day, 24 hours, 48 hours, 72 hours and 4 days after operation, respectively. No postoperative complication was detected. Results of postoperative pathological examination: moderate-differentiated rectal adenocarcinoma invaded serosal layer, with negative circumferential margin, negative distal margin of rectum and mesenteric lymph node metastasis (1 of 16 harvested lymph nodes was positive). Pathologic staging was T4aN1M0 (stage Ⅲb). The patient was discharged from hospital at postoperative day 6. (2) Follow-up and survival: the patient was followed up for 1 month, with a good survival. Conclusion Single-port Da Vinci robotic surgical system in the radical resection of rectal cancer is safe and feasible, with good short-term outcomes. Key words: Rectal neoplasms; Radical section; Da Vinci robotic surgical system; Single site