Recent advances in the management of rectal cancer: No surgery, minimal surgery or minimally invasive surgery

Laparoscopic Versus Open Pre-Treatment Loop Colostomy for Fecal Diversion in Rectal Cancer Patients: Is Laparoscopic Colostomy Better?

Diversion colostomy plays a crucial role in the management of carcinoma rectum in low- and middle-income countries as significant number of patients present with partial intestinal obstruction. The aim of this study was to compare laparoscopic and open approaches for fecal diversion done in patients with adenocarcinoma of the rectum as a pretreatment procedure. The primary end point of our study was time to initiation of neoadjuvant chemo radiation. It was a retrospective study that included all patients diagnosed to have carcinoma rectum and underwent a pretreatment fecal diversion between 2012 and 2014. A total of 55 patients underwent pretreatment diversion colostomy of which 33 were performed via the laparoscopic approach while 22 had open diversion. The time for initiation of neoadjuvant therapy was shorter in the laparoscopic group compared to the open approach (16 days vs. 20.5 days, P = 0.31). The study concluded that pretreatment diversion colostomy using the laparoscopic approach was a safe option in low- and middle-income countries as it was associated with faster recovery and early initiation of neoadjuvant therapy in patients with partially obstructed locally advanced carcinoma rectum.

Transanal minimally invasive surgery - A single-center experience

Background

Transanal minimally invasive surgery (TAMIS) was described in the literature 10 years ago. This procedure requires laparoscopic technical skills. It has been well accepted widely worldwide. TAMIS has been applied to multiple procedures, including excision for rectal polyps and cancer, with acceptable outcomes. The study aimed to assess the outcomes of TAMIS in a large district general hospital.

Methodology

A retrospective study on prospectively collected data on 52 consecutive patients of TAMIS performed in a single unit was conducted between May 2014 and February 2020. Data were collected on patient demographics, clinical diagnosis, peri-operative findings, pathological findings, adequacy of excision and complications. Patients were followed up as per the trust and national post-polypectomy guidelines.

Results

Among the 52 patients, TAMIS procedures were completed in 50 patients, of which 31 were female. The procedure was successful in 96.5% but had to abandon in two cases. There was no conversion to another procedure. Pre-operative indications were rectal polyps and one case was an emergency TAMIS in a patient who was bleeding following incomplete colonoscopic polypectomy. The final histology reported that the majority were benign polyps (46), and only 11 cases were malignant. The median distance of the lesion from the anal verge was 6 cm (3-10 cm). The median operative time was 55 min (8-175 min). A total of 45 (77.5%) lesions were completely excised and had negative microscopic margins. Most patients (64%) were discharged home the same day. No complications were observed at a median follow-up of 20 months (6-48 months). There was no mortality.

Conclusions

Our data suggest that TAMIS can be safely performed in a district general hospital for both benign and early rectal cancer. TAMIS was also able to control post-polypectomy bleeding and completion of rectal polypectomy. In selected cases, day-case TAMIS is safe and feasible.

Endoluminal ultrasound versus magnetic resonance imaging in assessment of rectal cancer after neoadjuvant therapy

BACKGROUND

Accurate rectal tumor staging guides the choice of treatment options. EUS and MRI are the main modalities for staging.

AIM OF THE WORK

To compare the performance of EUS and MRI for loco-regional staging of anorectal cancer after neo-adjuvant therapy.

METHODS

Seventy-three (37 male, 36 female) patients with rectal cancer after neo-adjuvant chemoradiotherapy were enrolled. Histopathological staging after surgery were used as reference for comparing the yield of loco-regional staging for EUS and MRI. EUS and MRI were done 1 month after completion of neo-adjuvant therapy.

RESULTS

Regarding post-surgical T staging, eight patients had early tumor (T2 = 16 and T1 = 9) and thirty six were locally advanced (T3 = 36), while N staging, forty patients with negative nodes and 33 were positive (N1 = 22 and N2 = 11). Comparing EUS to MRI, it showed a higher sensitivity (95.7% vs. 78.7%), specificity (84.6% vs. 68.0%) and accuracy (91.8% vs. 75.3%) for staging early and locally advanced tumor. Also, it had a higher sensitivity (78.8% vs. 69.7%), specificity (75.0% vs. 65.0%) and accuracy (76.7% vs. 67.1%) for detection of lymph nodes.

CONCLUSION

EUS appears to be more accurate than MRI in loco-regional staging of rectal carcinoma after neo-adjuvant therapy.

Functional Outcomes after Transanal Surgery

Transanal surgery has gained in popularity during the latter part of the last decade for both rectal cancer and benign disease. The current role for local excision of early rectal neoplastic lesions has expanded due to better understanding of risk factors for lymph node metastasis and heightened awareness for the long-term sequelae of radical surgery. Transanal resection of the rectum (both for cancer or inflammatory bowel diseases) has now been established as a successful procedure that overcomes some of the limitations of the abdominal approaches. Once the feasibility, safety, and the oncologic results of transanal minimally invasive approaches for patients with rectal cancer have been acknowledged, quality of life and functional outcomes have become increasingly important issues. This article provides an overview of the different techniques currently available for the minimally invasive transanal treatment of rectal lesions, particularly focusing on functional outcomes.

Changes in rectal cancer treatment after the introduction of a national screening program; Increasing use of less invasive strategies within a national cohort

AIM

Organ preserving treatment strategies and the introduction of a colorectal cancer-screening program have likely influenced the resection rates of rectal cancer. The aim of this study is to assess the influence of these developments on rectal cancer treatment and resection rates in the Netherlands.

METHODS

Patients diagnosed with non-metastatic rectal cancer between 2013 and 2018, were selected from the Netherlands Cancer Registry. The distribution of surgical and neo-adjuvant treatment and resection rates were analyzed and compared over time.

RESULTS

Between 2013 and 2018 22640 patients were diagnosed with non-metastatic rectal cancer. The incidence of early stage (cT1) disease increased from 141 (4%) in 2013 to 448 (12%) in 2018. The use of neoadjuvant radiotherapy and chemo-radiotherapy dropped from 39% to 21% and 34%-25%, respectively. A decrease in surgical resection rates (including TEM) was observed from 85% to 73%. The proportion of patients who underwent endoscopic resections increased from 3% to 10%. The decrease in surgical resection rates was larger in patients treated with neo-adjuvant chemo-radiotherapy.

CONCLUSION

An increase in stage I disease is noted after the introduction of the screening program. Surgical resection rates for rectal cancer have fallen over time. Endoscopic resections due to more early-stage disease probably accounts for a large part of this decline. Furthermore, a watch and wait approach after neo-adjuvant chemo-radiotherapy may play an important role as well.

Treatment of clinical T1 rectal cancer in the Netherlands; a population-based overview of clinical practice

INTRODUCTION

Local excision is increasingly used as an alternative treatment for radical surgery in patients with early stage clinical T1 (cT1) rectal cancer. This study provides an overview of incidence, staging accuracy and treatment strategies in patients with cT1 rectal cancer in the Netherlands.

MATERIALS AND METHODS

Patients with cT1 rectal cancer diagnosed between 2005 and 2018 were included from the Netherlands Cancer Registry. An overview per time period (2005-2009, 2010-2014 and 2015-2018) of the incidence and various treatment strategies used, e.g. local excision (LE) or major resection, with/without neoadjuvant treatment (NAT), were given and trends over time were analysed using the Chi Square for Trend test. In addition, accuracy of tumour staging was described, compared and analysed over time.

RESULTS

In total, 3033 patients with cT1 rectal cancer were diagnosed. The incidence of cT1 increased from 540 patients in 2005-2009 to 1643 patients in 2015-2018. There was a significant increased use of LE. In cT1N0/X patients, 9.2% received NAT, 25.5% were treated by total mesorectal excision (TME) and 11.4% received a completion TME (cTME) following prior LE. Overall accuracy in tumour staging (cT1 = pT1) was 77.3%, yet significantly worse in cN1/2 patients, as compared to cN0 patients (44.8% vs 77.9%, respectively, p < 0.001).

CONCLUSION

Over time, there was an increase in the incidence of cT1 tumours. Both the use of neoadjuvant therapy and TME surgery in clinically node negative patients decreased significantly. Clinical accuracy in T1 tumour staging improved over time, but remained significantly worse in clinical node positive patients.

Quality of life in restorative versus non-restorative resections for rectal cancer: systematic review

Background

Low rectal cancers could be treated using restorative (anterior resection, AR) or non-restorative procedures with an end/permanent stoma (Hartmann’s, HE; or abdominoperineal excision, APE). Although the surgical choice is determined by tumour and patient factors, quality of life (QoL) will also influence the patient's future beyond cancer. This systematic review of the literature compared postoperative QoL between the restorative and non-restorative techniques using validated measurement tools.

Methods

The review was registered on PROSPERO (CRD42020131492). Embase and MEDLINE, along with grey literature and trials websites, were searched comprehensively for papers published since 2012. Inclusion criteria were original research in an adult population with rectal cancer that reported QoL using a validated tool, including the European Organization for Research and Treatment of Cancer QLQ-CR30, QLQ-CR29, and QLQ-CR38. Studies were included if they compared AR with APE (or HE), independent of study design. Risk of bias was assessed using the Risk Of Bias In Non-Randomized Studies of Interventions (ROBINS-I) tool. Outcomes of interest were: QoL, pain, gastrointestinal (GI) symptoms (stool frequency, flatulence, diarrhoea and constipation), and body image.

Results

Nineteen studies met the inclusion criteria with a total of 6453 patients; all papers were observational and just four included preoperative evaluations. There was no identifiable difference in global QoL and pain between the two surgical techniques. Reported results regarding GI symptoms and body image documented similar findings. The ROBINS-I tool highlighted a significant risk of bias across the studies.

Conclusion

Currently, it is not possible to draw a firm conclusion on postoperative QoL, pain, GI symptoms, and body image following restorative or non-restorative surgery. The included studies were generally of poor quality, lacked preoperative evaluations, and showed considerable bias in the data.

A systematic review and meta-analysis of robotic-assisted transabdominal total mesorectal excision and transanal total mesorectal excision: which approach offers optimal short-term outcomes for mid-to-low rectal adenocarcinoma?

BACKGROUND

Resection of low rectal adenocarcinoma can be challenging in the narrow pelvis of male patients. Transanal total mesorectal excision (TaTME) appears to offer technical advantages for distal rectal tumours, and robotic-assisted transabdominal TME (rTME) was introduced in effort to improve operative precision and ergonomics. However, no study has comprehensively compared these approaches. The aim of the present study was to perform a systematic review of the literature to compare postoperative short-term outcomes in rTME and TaTME.

METHODS

A systematic online search (1974-July 2020) of MEDLINE, Embase, web of science and google scholar was conducted for trials, prospective or retrospective studies involving rTME, or TaTME for rectal cancer. Outcome variables included: hospital stay; operation duration, blood loss; resection margins; proportion of histologically complete resected specimens; lymph nodes; overall complications; anastomotic leak, and 30-day mortality.

RESULTS

Sixty-two articles met the inclusion criteria, including 37 studies (3835 patients) assessing rTME resection, 23 studies (1326 patients) involving TaTME and 2 comparing both (165 patients). Operating time was longer in rTME (309.2 min, 95% CI 285.5-332.8) than in TaTME studies (256.2 min, 95% CI 231.5-280.9) (p = 0.002). rTME resected specimens had a larger distal resection margin (2.62 cm, 95% CI 2.35-2.88) than in TaTME studies (2.10 cm, 95% CI 1.83-2.36) (p = 0.007). Other outcome variables did not significantly differ between the two techniques.

CONCLUSIONS

rTME provides similar pathological and short-term outcomes to TaTME and both are reasonable surgical approaches for patients with mid-to-low rectal cancer. To definitively answer the question of the optimal TME technique, we suggest a prospective trial comparing both techniques assessing long-term survival as a primary outcome.

Influence of age on surgical treatment and postoperative outcomes of patients with colorectal cancer in Denmark and Yorkshire, England

AIM

Denmark and Yorkshire are demographically similar and both have undergone changes in their management of colorectal cancer to improve outcomes. The differential provision of surgical treatment, especially in the older age groups, may contribute to the magnitude of improved survival rates. This study aimed to identify differences in the management of colorectal cancer surgery and postoperative outcomes according to patient age between Denmark and Yorkshire.

METHOD

This was a retrospective population-based study of colorectal cancer patients diagnosed in Denmark and Yorkshire between 2005 and 2016. Proportions of patients undergoing major surgical resection, postoperative mortality and relative survival were compared between Denmark and Yorkshire across several age groups (18-59, 60-69, 70-79 and ≥80 years) and over time.

RESULTS

The use of major surgical resection was higher in Denmark than in Yorkshire, especially for patients aged ≥80 years (70.5% versus 50.5% for colon cancer, 49.3% versus 38.1% for rectal cancer). Thirty-day postoperative mortality for Danish patients aged ≥80 years was significantly higher than that for Yorkshire patients with colonic cancer [OR (95% CI) = 1.22 (1.07, 1.38)] but not for rectal cancer or for 1-year postoperative mortality. Relative survival significantly increased in all patients aged ≥80 years except for Yorkshire patients with colonic cancer.

CONCLUSION

This study suggests that there are major differences between the management of elderly patients with colorectal cancer between the two populations. Improved selection for surgery and better peri- and postoperative care in these patients appears to improve long-term outcomes, but may come at the cost of a higher 30-day mortality.

Validation of the standardized index of shape tool to analyze DCE-MRI data in the assessment of neo-adjuvant therapy in locally advanced rectal cancer

PURPOSE

Standardized index of shape (SIS) tool validation to examine dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) in preoperative chemo-radiation therapy (pCRT) assessment of locally advanced rectal cancer (LARC) in order to guide the surgeon versus more or less conservative treatment.

MATERIALS AND METHODS

A total of 194 patients (January 2008-November 2020), with III-IV locally advanced rectal cancer and subjected to pCRT were included. Three expert radiologists performed DCE-MRI analysis using SIS tool. Degree of absolute agreement among measurements, degree of consistency among measurements, degree of reliability and level of variability were calculated. Patients with a pathological tumour regression grade (TRG) 1 or 2 were classified as major responders (complete responders have TRG 1).

RESULTS

Good significant correlation was obtained between SIS measurements (range 0.97-0.99). The degree of absolute agreement ranges from 0.93 to 0.99, the degree of consistency from 0.81 to 0.9 and the reliability from 0.98 to 1.00 (p value <  < 0.001). The variability coefficient ranges from 3.5% to 26%. SIS value obtained to discriminate responders by non-responders a sensitivity of 95.9%, a specificity of 84.7% and an accuracy of 91.8% while to detect complete responders, a sensitivity of 99.2%, a specificity of 63.9% and an accuracy of 86.1%.

CONCLUSION

SIS tool is suitable to assess pCRT response both to identify major responders and complete responders in order to guide the surgeon versus more or less conservative treatment.

Communication in decision aids for stage I-III colorectal cancer patients: a systematic review

OBJECTIVES

To assess the communicative quality of colorectal cancer patient decision aids (DAs) about treatment options, the current systematic review was conducted.

DESIGN

Systematic review.

DATA SOURCES

DAs (published between 2006 and 2019) were identified through academic literature (MEDLINE, Embase, CINAHL, Cochrane Library and PsycINFO) and online sources.

ELIGIBILITY CRITERIA

DAs were only included if they supported the decision-making process of patients with colon, rectal or colorectal cancer in stages I-III.

DATA EXTRACTION AND SYNTHESIS

After the search strategy was adapted from similar systematic reviews and checked by a colorectal cancer surgeon, two independent reviewers screened and selected the articles. After initial screening, disagreements were resolved with a third reviewer. The review was conducted in concordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DAs were assessed using the International Patient Decision Aid Standards (IPDAS) and Communicative Aspects (CA) checklist.

RESULTS

In total, 18 DAs were selected. Both the IPDAS and CA checklist revealed that there was a lot of variation in the (communicative) quality of DAs. The findings highlight that (1) personalisation of treatment information in DAs is lacking, (2) outcome probability information is mostly communicated verbally and (3) information in DAs is generally biased towards a specific treatment. Additionally, (4) DAs about colorectal cancer are lengthy and (5) many DAs are not written in plain language.

CONCLUSIONS

Both instruments (IPDAS and CA) revealed great variation in the (communicative) quality of colorectal cancer DAs. Developers of patient DAs should focus on personalisation techniques and could use both the IPDAS and CA checklist in the developmental process to ensure personalised health communication and facilitate shared decision making in clinical practice.

Endorectal Ultrasound and Magnetic Resonance Imaging for Rectal Cancer Staging: A Modern Multimodality Approach

Preoperative staging represents a crucial point for the management, type of surgery, and candidacy for neoadjuvant therapy in patient with rectal cancer. The most recent clinical guidelines in oncology recommend an accurate preoperative evaluation in order to address early and advanced tumors to different therapeutic options. In particular, potential pitfalls may occur in the assessment of T3 tumors, which represents the most common stage at diagnosis. The depth of tumor invasion is known to be an important prognostic factor in rectal carcinoma; as a consequence, the T3 imaging classification has a substantial importance for treatment strategy and patient survival. However, the differentiation between tumor invasion of perirectal fat and mesorectal desmoplastic reactions remains a main goal for radiologists. Magnetic resonance imaging (MRI) is actually considered as the best imaging modality for rectal cancer staging. Although the endorectal ultrasound (ERUS) is the preferred staging method for early tumors, it could also be useful in identifying perirectal fat invasion. Moreover, the addiction of diffusion weighted imaging (DWI) improves the diagnostic performance of MRI in rectal cancer staging by adding functional information about rectal tumor and adjacent mesorectal tissues. This study investigated the diagnostic performance of conventional MRI alone, in combination with the DWI technique and ERUS in order to assess the best diagnostic imaging combination for rectal cancer staging.

End-to-end versus end-to-side anastomosis for low anterior resection: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Numerous randomized controlled trials comparing end-to-end and end-to-side anastomoses after low anterior resection have been performed. Rates of anastomotic leakage and overall postoperative morbidity, as well as reported quality of postoperative bowel function, vary across individual studies. As such, this study meta-analyzes pooled data comparing end-to-end and end-to-side anastomosis after low anterior resection in terms of anastomotic leak rate and postoperative bowel function.

METHODS

A search of Medline, EMBASE, and Cochrane Central Register of Controlled Trials was performed. Articles were included if they were randomized controlled trials that compared end-to-end and end-to-side anastomosis after low anterior resection for benign or malignant disease. The primary outcome was anastomotic leak rate. A pairwise meta-analysis was performed using inverse variance random effects.

RESULTS

From 1,452 citations, 6 randomized controlled trials with 270 patients undergoing end-to-end anastomosis (45.9% female, mean age: 63.5 years) and 268 patients undergoing end-to-side anastomosis (52.4% female, mean age: 64.0 years) met inclusion criteria. Patients undergoing end-to-side anastomosis had a significantly lower rate of anastomotic leak (RR 0.37, 95% CI 0.15-0.93, P = .04, I²=0%). There were no differences in rate of anastomotic stenosis (RR 1.03, 95% CI 0.21-5.19, P = .97) or overall postoperative morbidity (RR 0.60, 95% CI 0.33-1.07, P = .08). Narrative review of postoperative bowel function demonstrated evidence of improved Wexner scores for 6 months postoperatively in patients undergoing end-to-side anastomosis.

CONCLUSION

End-to-side anastomosis significantly reduces the risk of anastomotic leak after low anterior resection. Additional prospective trials are warranted to confirm the findings of this review and to contribute to the growing evidence-base aimed at optimization of bowel function after low anterior resection.

The Older Adults With Rectal Cancer-Does Age Matter?: A Single-center Experience

OBJECTIVES

Oncological treatments of older patients have many unresolved questions mainly because of the fact that these patients were not eligible to be included in most clinical trials. The aim of this study was to evaluate the treatment approach to localized rectal cancer in the older population, including complication rates and overall survival in patients treated with curative intent.

MATERIALS AND METHODS

A retrospective review of patients older than 80 years old (group A) who were treated for clinical stages II to III rectal cancer. The data collection included demographics, comorbidities, treatment protocols, adverse events, time of death, and a comparison with a group of patients aged 65 to 75 years (group B).

RESULTS

A total of 88 patients were included in the analysis (group A, 35; group B, 53). The groups were balanced with regards to sex, comorbidities, pretreatment albumin, and hemoglobin levels (for all categories P>0.05). More patients in group A (25%) received preoperative treatment as in-patients (P=0.022) and were treated with radiation only (P<0.0001) as the initial treatment approach. In group A, in 82% of patients the initial chemotherapy dose was reduced to 75% or less of the calculated dose compared with 7% in group B (P<0.001). Discontinuation of chemotherapy was needed in 55% in group A and 31% in group B (P=0.07). Median overall survival was 33 months in group A and 55 months in group B (P=0.06), 5-year overall survival was 27% and 60%, respectively (P=0.004).

CONCLUSIONS

The age has a significant implication on preoperative treatment, chemotherapy dose, hospitalization rates, and survival.

Comparison of the transanal surgical techniques for local excision of rectal tumors: a network meta-analysis

BACKGROUND

In order to assess the various surgical modalities for local resection of rectal tumors, a systematic review of the current literature and a network meta-analysis (NMA) was designed and conducted.

METHODS

The present study adhered to the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions principles. Scholar databases (Medline, Scopus, Web of Science) were systematically screened up to 23/12/2019. A Bayesian NMA, implementing a Markov chain Monte Carlo analysis, was introduced for the probability ranking of the available surgical methods. Odds ratio (OR) and weighted mean difference (WMD) of the categorical and continuous variables, respectively, were reported with the corresponding 95% confidence interval (95%CI).

RESULTS

Overall, 16 studies and 2146 patients were introduced in our study. Transanal minimal invasive surgery (TAMIS) displayed the highest performance regarding the overall postoperative morbidity, the perioperative blood loss, the length of hospitalization, and the peritoneal violation rate. Transanal endoscopic microsurgery (TEM) was the most efficient modality for resecting an intact specimen. Although transanal local excision (TAE) had the highest ranking considering operative duration, it was associated with a significant risk for positive resection margins and tumor recurrence.

CONCLUSIONS

In conclusion, TEM and TAMIS display superior oncological results over TAE. Due to several limitations, validation of these results requires further RCTs of a higher methodological level.

Management of rectal cancer in Canada: an evidence-based comparison of clinical practice guidelines

Background

Rectal cancer requires a multidisciplinary and multimodality treatment approach. Clinical practice guidelines (CPGs) provide a framework for delivering consistent, evidence-based health care. We compared provincial/territorial CPGs across Canada to identify areas of variability and evaluate their quality.

Methods

We retrieved CPGs from Canadian organizations responsible for cancer care oversight and evaluated their quality and developmental methodology using the AGREE-II instrument. Recommendations for diagnostic and staging investigations, treatment by stage, and post-treatment surveillance of stage I–III rectal cancers were abstracted and compared.

Results

We identified 7 sets of CPGs for analysis, varying in content, presentation, quality, and year last updated. Differences were noted in locoregional staging: 4 recommended magnetic resonance imaging over endorectal ultrasonography, 2 recommended either modality, and 3 specified scenarios for one over the other. Recommendations also varied for use of staging computed tomography of the chest versus chest radiography and for surgical management and indications for transanal excision. Recommendations for neoadjuvant therapy in stage II/III disease also differed: 3 guidelines recommended long-course chemoradiation over short-course radiation therapy alone, while 3 others recommended short-course radiation in specific clinical scenarios. Adjuvant chemotherapy for stage II/III disease was uniformly recommended, with variable protocols. The use of proctosigmoidoscopy and interval/duration of endoscopic post-treatment surveillance varied among guidelines.

Conclusion

Canadian CPGs vary in their recommendations for staging, treatment, and surveillance of rectal cancer. Some of these differences reflect areas with limited definitive evidence. Consistent guidelines with uniform implementation across provinces/territories may lead to more equitable care to patients.

The outcomes of two robotic platforms performing transanal minimally invasive surgery for rectal neoplasia: a case series of 21 patients

Colorectal cancer remains the third most common cancer effecting adults. Surgical guidelines recommend transanal excision of early rectal neoplasia up to 8 cm from the anal verge. A retrospective review of two novel approaches for transanal robotic local excision with R0 resections of rectal cancers which was, on average, higher than 8 cm. Twenty-one cases of robotic assisted transanal surgery for early stage disease (T0-T1, N0) were reviewed. The first 10 cases performed with the da Vinci^® Si robotic platform between 2013 and 2016, and the first 11 cases performed using the Flex^® Medrobotics platform between August 2017 and August 2018. The average distance from the anal verge was 11.1 cm and 9.5 cm for the da Vinci^® Si and Flex^® Colorectal Drive, respectively. The average operative time was 167.6 min for the da Vinci^® Si and 110.1 min for the Flex^® Colorectal Drive; the average EBL was 37.5 cc and 9.1 cc for the da Vinci^® Si and Flex^® Colorectal Drive. In the da Vinci^® series, four cases required intraoperative conversion. In the Flex^® series, one case was aborted due to unfavorable robotic positioning. All margins were histologically negative when surgically complete with no recurrences to date. Transanal robotic surgery may provide a method to address rectal lesions farther from the anal verge than previously described. The Flex^® Colorectal Drive platform may provide superior ability to navigate the nonlinear anatomy of the rectum and distal sigmoid colon.

The accuracy of trans rectal ultrasonography (TRUS) in early-stage rectal cancer or benign adenomas

Background: Screening for colorectal cancer in Denmark has resulted in more patients being diagnosed with benign adenomas and early-stage rectal cancer. In general, TRUS is accepted as a good modality for evaluating the above mentioned before deciding on surgery. Objective: To investigate the accuracy of TRUS in a clinical setting at the Region Hospital in Herning, Denmark. Study design: Retrospective cohort study from January 2016 to June 2018. Methods: Quantitative method. The cohort (117 patients) was recruited by searching for specific procedure codes. Data were collected by going through the electronic patient files. Results: TRUS predicted T0, T1, T2 and T3 with an accuracy of 91%, 35%, 43% and 20% respectively and an overall accuracy of 68%. A weighted Cohens kappa value of 0.30 (p  ≤  .05). TRUS differentiated between T0/T1 with a sensitivity of 70%, specificity of 85% and an accuracy of 85% and kappa value of 0.44 (p  ≤  .05). Conclusion: TRUS can with great precision establish whether the tumor is benign so correct local treatment can be instituted.

Stability of radiomic features of apparent diffusion coefficient (ADC) maps for locally advanced rectal cancer in response to image pre-processing

Quantitative imaging features (radiomics) extracted from apparent diffusion coefficient (ADC) maps of rectal cancer patients can provide additional information to support treatment decision. Most available radiomic computational packages allow extraction of hundreds to thousands of features. However, two major factors can influence the reproducibility of radiomic features: interobserver variability, and imaging filtering applied prior to features extraction. In this exploratory study we seek to determine to what extent various commonly-used features are reproducible with regards to the mentioned factors using ADC maps from two different clinics (56 patients). Features derived from intensity distribution histograms are less sensitive to manual tumour delineation differences, noise in ADC images, pixel size resampling and intensity discretization. Shape features appear to be strongly affected by delineation quality. On the whole, textural features appear to be poorly or moderately reproducible with respect to the image pre-processing perturbations we reproduced.

Assessing response to neo-adjuvant therapy in locally advanced rectal cancer using Intra-voxel Incoherent Motion modelling by DWI data and Standardized Index of Shape from DCE-MRI

Background:

Our aim was to investigate preoperative chemoradiation therapy (pCRT) response in locally advanced rectal cancer (LARC) comparing standardized index of shape (SIS) obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with intravoxel-incoherent-motion-modelling-derived parameters by diffusion-weighted imaging (DWI).

Materials and methods:

Eighty-eight patients with LARC were subjected to MRI before and after pCRT. Apparent diffusion coefficient (ADC), tissue diffusion (D_t), pseudodiffusion (D_p) and perfusion fraction (f) were calculated and percentage changes ∆ADC, ∆D_t, ∆D_p, ∆f were computed. SIS was derived comparing DCE-MRI pre- and post-pCRT. Nonparametric tests and receiver operating characteristic (ROC) curves were performed.

Results:

A total of 52 patients were classified as responders (tumour regression grade; TRG ⩽ 2) and 36 as not-responders (TRG > 3). Mann–Whitney U test showed statistically significant differences in SIS, ∆ADC and ∆D_t between responders and not-responders and between complete responders (19 patients with TRG = 1) versus incomplete responders. The best parameters to discriminate responders by nonresponders were SIS and ∆ADC, with an accuracy of 91% and 82% (cutoffs of −5.2% and 18.7%, respectively); the best parameters to detect pathological complete responders were SIS, ∆f and ∆D_p with an accuracy of 78% (cutoffs of 38.5%, 60.0% and 83.0%, respectively). No increase of performance was observed by combining linearly each possible couple of parameters or combining all parameters.

Conclusion:

SIS allows assessment of preoperative treatment response with high accuracy guiding the surgeon versus more or less conservative treatment. DWI-derived parameters reached less accuracy compared with SIS and combining linearly DCE- and DWI-derived parameters; no increase of accuracy was obtained.

Robotic transanal microsurgery for high early rectal neoplasia (T0-T1, N0 lesions), case series of 10 patients

PURPOSE/BACKGROUND

In 2017, an estimated 39 910 people will receive a new diagnosis of rectal cancer. Current surgical guidelines limit transanal excision of early rectal neoplasia to 8 cm from the anal verge. We report that R0 resection of higher rectal cancers is possible using transanal robotic microsurgery.

METHODS/INTERVENTIONS

Ten cases of robotic assisted transanal surgery for early stage disease (T0-T1, N0) between 2013 and 2016 were reviewed.

RESULTS/OUTCOMES

All cases were diagnosed preoperatively with colonoscopy, and the average distance from the anal verge was 11.1 cm. The average operative time was 167 minutes, and the average blood loss was 37.5 cc. Four cases required intraoperative conversion; one conversion required robotic abdominal access to repair a proctotomy. All margins were histologically negative, and 6-month follow-up showed no recurrences.

CONCLUSION/DISCUSSION

Transanal robotic surgery may provide the colorectal surgeon a method to address rectal lesions farther from the anal verge.

Transanal Total Mesorectal Excision for Treatment of Carcinoma in the Middle or Lower Third Rectum: the Technical Feasibility of the Procedure, Pathological Results, and Clinical Outcome

We are trying to illustrate operative, short-term, and pathological outcomes of transanal total mesorectal excision (TaTME) as a surgical procedure for patients who are suffering cancer in the lower or middle rectum. This study included 25 consecutive patients who underwent TaTME for the mid and low cancer rectum. The primary outcome measures included frequency of postoperative (PO) bleeding, leakage, ileus, days to regain bowel function, days for Foley's removal, and erectile function. The secondary outcome measures included operation time, status of resection margins, number, the quality of TME, and duration PO hospital stay. No recorded intraoperative complications. The mean hospital stay was 6.9 ± 2.6 days. The mean duration need for urinary catheter removal and flatus passage were 2.4 ± 2.1 and 1.5 + 0.9 days, respectively. The mean IPSS was returned to normal 12 months after surgery. The mean distal margin distance was 1.9 ± 1.1. Circumferential margin distance was > 1 mm in 23 (92%) patients. The mesorectum was complete in 22 (88%) patients. The survival rate was 88% over 3 years. TaTME could be considered as a safe, feasible, and effective surgical modality for patients who had mid and lower rectal tumors with an excellent pathological outcome.

Redo transanal total mesorectal excision (Re-TaTME) after initial TaTME; is it possible?

Rectal cancer is one of the commonest human malignancies. Treatment of this serious disease conventionally involves resection with/without anastomosis. Anastomotic site stenosis is a serious complication of rectal resection for which treatment is still evolving. We report a male patient treated with minimally invasive abdominal and anal approach for stenosis after initial transanal total mesorectal excision (TaTME) for rectal cancer. Surgeons are encouraged to put this technique in their mind while treating similar cases.