The Impact of a Modular Robotic Total Mesorectal Excision Training Program on Perioperative and Oncological Outcomes in Robotic Rectal Cancer Surgery.

BACKGROUND: Structured training programs for robotic colorectal surgery are limited, and there are concerns about surgical outcomes and operating times. OBJECTIVE: To compare perioperative and oncological outcomes of robotic total mesorectal excision for rectal cancer performed by expert consultants and surgical trainees in a modular surgical training program. DESIGN: Retrospective cohort study. SETTINGS: Conducted at a colorectal training referral center for robotic surgery. PATIENTS: Consecutive robotic total mesorectal excision cases between May 2013 and December 2017 were evaluated retrospectively from a prospectively maintained institutional database and divided into 2 groups: group I comprised expert surgeons and group II comprised supervised trainees. Robotic total mesorectal excision training modules (5 modules) were performed stepwise with increasing complexity. Patients' demographic, perioperative, and oncological data were collected. INTERVENTIONS: Modular robotic training. MAIN OUTCOME MEASURES: Comparable R0 resection rate, lymph node harvest, and oncological outcomes between experts and trainees, suggesting good quality in oncological resection. RESULTS: A total of 177 robotic total mesorectal excision resections were performed (group I: n = 80, group II: n = 97). Four trainees completed 37.5 modules each. Patients' age, sex, and BMI were similar between groups. Group II had a higher ASA III score (6.3% vs 25.8%, p = 0.002). Clinical TNM and neoadjuvant chemoradiotherapy rates were similar. Group II had a longer operative time (225 [197.5-297.5] vs 250 [230-300] minutes, p = 0.004). No conversion occurred. There were no differences in intra- or postoperative outcomes between groups. The rate of R0 resection and the number of harvested lymph nodes were also similar between groups. The median follow-up was 75 (64.0-81.7) and 47 (38.0-55.0) months, respectively. Local and distant recurrence rates, 5-year overall survival (81.1% group I vs 81.3% group II, p = 0.832), and 5-year disease-free survival (79.7% group I vs 80.7% group II, p = 0.725) were similar between groups. LIMITATIONS: The groups operated in 2 consecutive periods. CONCLUSIONS: The robotic total mesorectal excision modular surgical training program maximizes training experience without significantly affecting the perioperative and oncological outcomes of patients with rectal cancer. See Video Abstract. EL IMPACTO DEL PROGRAMA MODULAR DE ENTRENAMIENTO EN ESCISIN MESORRECTAL TOTAL ROBTICA EN LOS RESULTADOS PERIOPERATORIOS Y ONCOLGICOS EN LA CIRUGA ROBTICA DEL CNCER DE RECTO: ANTECEDENTES:Los programas de entrenamiento estructurados para la cirugía colorrectal robótica están limitados debido a preocupaciones sobre los resultados quirúrgicos y los tiempos de operación.OBJETIVO:Comparar los resultados perioperatorios y oncológicos de la escisión mesorrectal total robótica para el cáncer de recto realizada por consultores expertos y aprendices de cirugía en un programa modular de entrenamiento quirúrgica.DISEÑO:Estudio de cohorte retrospectivo.AJUSTES:Realizado en un centro de referencia de entrenamiento colorrectal para cirugía robótica.PACIENTES:Se evaluaron retrospectivamente casos consecutivos de escisión mesorrectal total robótica entre mayo de 2013 y diciembre de 2017 a partir de una base de datos institucional mantenida prospectivamente y se dividieron en dos grupos: Grupo I: cirujanos expertos; Grupo II: aprendices supervisados. Los módulos de entrenamiento robótico de escisión mesorrectal total (cinco módulos) se realizaron paso a paso con complejidad creciente. Se recogieron datos demográficos, perioperatorios y oncológicos.INTERVENCIONES:Entrenamiento modular en robótica.PRINCIPALES MEDIDAS DE RESULTADO:Tasa de resección R0 comparable, extracción de ganglios linfáticos y resultados oncológicos entre expertos y aprendices que sugieren buena calidad en la resección oncológica.RESULTADOS:Se realizaron un total de 177 resecciones por escisión mesorrectal total robótica (Grupo I: n = 80, Grupo II: n = 97). Cuatro alumnos completaron 37,5 módulos cada uno. La edad, el sexo y el IMC fueron similares entre los grupos. El grupo II tuvo una puntuación más alta de la Sociedad Americana de Anestesiólogos III (6,3% frente a 25,8%, p = 0,002). Las tasas clínicas de TNM y quimiorradioterapia neoadyuvante fueron similares. El grupo II tuvo mayor tiempo operatorio (225 (197,5-297,5) vs 250 (230-300) minutos, p = 0,004). No se produjo ninguna conversión. No hubo diferencias en los resultados intra o posoperatorios entre los grupos. La tasa de resección R0 y el número de ganglios linfáticos extraídos también fueron similares entre los grupos. La mediana de seguimiento fue de 75 (64,0-81,7) y 47 (38,0-55,0) meses, respectivamente. Tasas de recurrencia local y a distancia, supervivencia general a 5 años (81,1% Grupo I vs. 81,3% Grupo II, p = 0,832) y supervivencia libre de enfermedad a 5 años (79,7% Grupo I vs. 80,7% Grupo II, p = 0,725) fueron similares entre los grupos.LIMITACIONES:Los grupos operaron en dos períodos consecutivos.CONCLUSIONES:El programa de entrenamiento quirúrgico modular para la escisión mesorrectal total robótica maximiza la experiencia de capacitación sin afectar significativamente los resultados perioperatorios y oncológicos de los pacientes con cáncer de recto. (Traducción-Dr. Aurian Garcia Gonzalez).

Short-term clinical outcomes of a European training programme for robotic colorectal surgery.

BACKGROUND: Despite there being a considerable amount of published studies on robotic colorectal surgery (RCS) over the last few years, there is a lack of evidence regarding RCS training pathways. This study examines the short-term clinical outcomes of an international RCS training programme (the European Academy of Robotic Colorectal Surgery-EARCS). METHODS: Consecutive cases from 26 European colorectal units who conducted RCS between 2014 and 2018 were included in this study. The baseline characteristics and short-term outcomes of cases performed by EARCS delegates during training were analysed and compared with cases performed by EARCS graduates and proctors. RESULTS: Data from 1130 RCS procedures were collected and classified into three cohort groups (323 training, 626 graduates and 181 proctors). The training cases conversion rate was 2.2% and R1 resection rate was 1.5%. The three groups were similar in terms of baseline characteristics with the exception of malignant cases and rectal resections performed. With the exception of operative time, blood loss and hospital stay (training vs. graduate vs. proctor: operative time 302, 265, 255 min, p < 0.001; blood loss 50, 50, 30 ml, p < 0.001; hospital stay 7, 6, 6 days, p = 0.003), all remaining short-term outcomes (conversion, 30-day reoperation, 30-day readmission, 30-day mortality, clinical anastomotic leak, complications, R1 resection and lymph node yield) were comparable between the three groups. CONCLUSIONS: Colorectal surgeons learning how to perform RCS under the EARCS-structured training pathway can safely achieve short-term clinical outcomes comparable to their trainers and overcome the learning process in a way that minimises patient harm.

The split scar sign as an indicator of sustained complete response after neoadjuvant therapy in rectal cancer.

OBJECTIVES: To measure the diagnostic performance of a new radiologic pattern on restaging magnetic resonance (MR) high-resolution T2-weighted imaging (T2-WI)-the split scar sign-for the identification of sustained complete response (SCR) after neoadjuvant therapy in rectal cancer. METHODS: Institutional review board approval was obtained for this retrospective study and the informed consent requirement was waived. Fifty-eight consecutive patients with rectal cancer who underwent neoadjuvant therapy were enrolled. Two radiologists blindly and independently reviewed restaging pelvic MR imaging and recorded the presence/absence of the split scar sign (mrSSS). On a second round, they also assessed the relative proportion of intermediate signal intensity on T2-WI (mrT2) and of high signal intensity on high b-value diffusion-weighted imaging (mrDWI). Endoscopic response grading records were retrieved. Qui-square test was employed in search for associations between SCR, defined as pathologic complete response or long-term recurrence-free clinical follow-up, and mrSSS, mrT2, mrDWI and endoscopy. Interobserver agreement for imaging parameters was estimated using Cohen's kappa (k). RESULTS: mrSSS was significantly associated with SCR, with specificity = 0.97/0.97, sensitivity = 0.52/0.64, PPV = 0.93/0.94, NPV = 0.73/0.78, and AuROC = 0.78/0.83, for observers 1/2, respectively. mrDWI was significantly associated with SCR for observer 2, with specificity = 0.76, sensitivity = 0.60, PPV = 0.65, NPV = 0.71, and AuROC = 0.69. mrT2 and endoscopy were not discriminative. Interobserver agreement was substantial for mrSSS (k = 0.69), moderate for mrDWI (k = 0.46), and poor for mrT2 (k = 0.17). CONCLUSION: The split scar sign is a simple morphologic pattern visible on restaging T2-WI which, although not sensitive, is very specific for the identification of sustained complete responders after neoadjuvant therapy in rectal cancer. KEY POINTS: • The split scar sign is a morphologic pattern visible on high-resolution T2-weighted MR imaging in rectal cancer patients after neoadjuvant therapy. It therefore does not require any changes to standard protocol. • At first restaging pelvic MR imaging (mean: 9.1 weeks after the end of radiotherapy), the split scar sign identified patients who sustained a complete response with very high specificity (0.97) and positive predictive value (0.93-0.94). • The split scar sign has the potential to improve patient selection for "watch-and-wait" after neoadjuvant therapy in rectal cancer.

Standardised approach to laparoscopic total mesorectal excision for rectal cancer: a prospective multi-centre analysis.

PURPOSE: Two non-inferiority randomised control trials have questioned the utility of laparoscopic surgery for rectal cancer by failing to prove that pathological markers of high-quality surgery are equivalent to those achieved by open technique. We present short- and long-term post-operative outcomes from the largest single surgeon series of consecutive patients undergoing laparoscopic TME for rectal cancer. We describe the standardised laparoscopic technique developed by the principal surgeon, and the short-term outcomes from three surgeons who were trained in and subsequently adopted the same approach. METHODS: Prospectively acquired data from consecutive patients undergoing surgery for rectal cancer by the principal surgeon at the minimally invasive colorectal unit in Portsmouth between 2006 and 2014 were analysed along with data acquired between 2010 and 2017 from surgeons at three further international centres. Endpoints were overall and disease-free survival at 5 years, and early post-operative clinical and pathological outcomes. RESULTS: Two hundred sixty-three consecutive patients underwent laparoscopic TME surgery by the principal surgeon. At 5 years, overall survival was 82.9% (Dukes' A = 94.4%; B = 81.6%; C = 73.7%); disease-free survival was 84.0% (Dukes' A = 93.3%; B = 86.8%; C = 72.6%). Post-operative length of stay, lymph node harvest, mean operating time, rate of conversion, major morbidity and 30-day mortality were not significantly different between the principal surgeon and those he had trained when subsequently in independent practices. CONCLUSION: Laparoscopic TME produces excellent long-term survival outcomes for patients with rectal cancer. A standardised approach has the potential to improve outcomes by setting benchmarks for surgical quality, and providing a step-by-step method for surgical training.

Oncological and Survival Outcomes in Watch and Wait Patients With a Clinical Complete Response After Neoadjuvant Chemoradiotherapy for Rectal Cancer: A Systematic Review and Pooled Analysis.

OBJECTIVE: The aim of this study was to evaluate the oncological and survival outcomes of a Watch and Wait policy in rectal cancer after a clinical complete response (cCR) following neoadjuvant chemoradiotherapy. BACKGROUND: The detection of a cCR after neoadjuvant treatment may facilitate a nonoperative approach in selected patients. However, the long-term safety of this strategy remains to be validated. METHOD: This is a systematic review of the literature to determine the oncological outcomes in Watch and Wait patients. The primary outcome was the cumulative rate of local regrowth, success of salvage surgery, and incidence of metastases. We also evaluated survival outcomes. A pooled analysis of manually extracted summary statistics from individual studies was carried out using inverse variance weighting. RESULTS: Seventeen studies comprising 692 patients were identified; incidence of cCR was 22.4% [95% confidence interval (CI),14.3-31.8]. There were 153 (22.1%) local regrowths, of which 96% (n = 147/153) manifested in the first 3 years of surveillance. The 3-year cumulative risk of local regrowth was 21.6% (95% CI, 16.0-27.8). Salvage surgery was performed in 88% of patients, of which 121 (93%) had a complete (R0) resection. Fifty-seven metastases (8.2%) were detected, and 35 (60%) were isolated without evidence of synchronous regrowths; 3-year incidence was 6.8% (95% CI, 4.1-10.2). The 3-year overall survival was 93.5% (95% CI, 90.2-96.2). CONCLUSION: In rectal cancer patients with a cCR following neoadjuvant chemoradiotherapy, a Watch and Wait policy appears feasible and safe. Robust surveillance with early detection of regrowths allows a high rate of successful salvage surgery, without an increase in the risk of systemic disease, or adverse survival outcomes.

The Future of Rectal Cancer Surgery: A Narrative Review of an International Symposium.

Surgery remains the mainstay of curative treatment for primary rectal cancer. For mid and low rectal tumors, optimal oncologic surgery requires total mesorectal excision (TME) to ensure the tumor and locoregional lymph nodes are removed. Adequacy of surgery is directly linked to survival outcomes and, in particular, local recurrence. From a technical perspective, the more distal the tumor, the more challenging the surgery and consequently, the risk for oncologically incomplete surgery is higher. TME can be performed by an open, laparoscopic, robotic or transanal approach. There is a lack of consensus on the "gold standard" approach with each of these options offering specific advantages. The International Symposium on the Future of Rectal Cancer Surgery was convened to discuss the current challenges and future pathways of the 4 approaches for TME. This article reviews the findings and discussion from an expert, international panel.

Local Excision Techniques for Rectal Cancer After Neoadjuvant Chemoradiotherapy: What Are We Doing?

BACKGROUND: Recent evidence shows that the majority of rectal cancers demonstrate occult tumor scatter after neoadjuvant chemoradiotherapy that can extend for several centimeters under adjacent normal-appearing mucosa beside the residual mucosal abnormality or scar. OBJECTIVE: This systematic review aimed to determine all of the published selection criteria and technical descriptions for local excision to date with regard to this phenomenon. DATA SOURCES: PubMed, MEDLINE, and Embase were searched using the following key words: rectal cancer, local excision, radiotherapy, and neoadjuvant. STUDY SELECTION: Studies that assessed local excision of rectal cancer after neoadjuvant chemoradiotherapy were included. Duplicate series were excluded from final analysis. INTERVENTION: All of the data points were tabulated and analyzed using Microsoft Excel. MAIN OUTCOME MEASURES: Criteria for patient selection, surgical technique, clinical restaging, pathologic assessment, and indications for completion surgery were analyzed. RESULTS: After exclusions, data from 25 studies that in total evaluated local excision in 1001 patients were included. Compared with the single accepted technique of total mesorectal excision, described techniques for local excision after neoadjuvant therapy demonstrate significant variability in many critical technical issues, such as marking/tattooing original tumor margins before neoadjuvant therapy, using pretreatment tumor size/stage as exclusion criteria, and specifically stating lateral excision margins. Where detailed, the majority of local recurrences occurred in patients with clear pathological margins, yet significant variation existed for pathological assessment and reporting, with few studies detailing R status and some not reporting margin status at all. Significant variability also existed for adverse tumor features that mandated completion surgery, and, importantly, many series describe patients refusing completion surgery where indicated. LIMITATIONS: We were unable to perform meta-analysis because studies lacked sufficient methodologic homogeneity to synthesize. CONCLUSIONS: The observations from this study prompt additional study, standardization of technique, and cautious use of local excision of rectal cancer in the setting of neoadjuvant chemoradiotherapy.

The Perfect Total Mesorectal Excision Obviates the Need for Anything Else in the Management of Most Rectal Cancers.

This article discusses the local control of primary rectal cancer and its locoregional spread in the light of modern advances. In recent years, the use of neoadjuvant chemoradiation has spread widely. However, its true benefit is not always balanced with its morbidities. Often total mesorectal excision (TME) is the best option. We will discuss the indications for immediate surgery for chemoradiation in advance and the importance of a delay in the management plan. To understand this selection, it is mandatory to know the true extent of tissue at risk for tumor dissemination and spread. Considering that TME may be enough for many patients and that most local recurrences are failures of surgical technique we introduce a new concept of total mesorectal irradiation. This exploits the new reality that precise, focused neoadjuvant therapy can offer a better response with fewer complications. Together these important changes in cancer board (multidisciplinary team) planning can also offer selected patients complete control of their cancer with no need for surgery.

The prognostic significance of postchemoradiotherapy high-resolution MRI and histopathology detected extramural venous invasion in rectal cancer.

OBJECTIVE: This study aimed to determine the prognostic significance of extramural venous invasion (EMVI) after chemoradiotherapy (CRT) by both magnetic resonance imaging (MRI) (ymrEMVI) and histopathology (ypEMVI). BACKGROUND: EMVI is a prognostic factor in rectal cancer but whether this remains so after CRT preoperative is unknown. Histopathological definitions of EMVI are variable and lead to underreporting particularly after CRT. METHODS: All consecutive patients staged on initial MRI as EMVI-positive undergoing preoperative CRT and curative surgery between Jan 2006 and Jan 2012 were included. Posttreatment EMVI status (yEMVI) was reevaluated for both MRI and pathology. The primary endpoint of disease-free survival (DFS) for ymrEMVI and ypEMVI was calculated using the Kaplan-Meier product limit and compared with a Mantel-Cox log-rank test. A P < 0.05 was considered significant. Hazard ratios (HRs) for disease recurrence were generated using Cox proportional hazard regression for MRI and histopathology tumor characteristics. RESULTS: A total of 188 patients who had evidence of EMVI on initial baseline MRI staging were included. MRI detected significantly more patients with persistent EMVI than histopathology (53% vs 19%) but both were prognostic for worse survival-ymrEMVI (HR 1.97) and ypEMVI (HR 2.39). Patients with persistent ymrEMVI-positivity had significantly worse DFS at 3 years (42.7%) compared with ymrEMVI-negative tumors (79.8%); DFS for was 36.9% versus 65.9% positive and negative ypEMVI, respectively. CONCLUSIONS: Detection of EMVI post-CRT is prognostically significant whether detected by MRI or histopathology. EMVI status after treatment may be used to counsel patients regarding ongoing risks of metastatic disease, implications for surveillance, and systemic chemotherapy.

Can the Heald anal stent help to reduce anastomotic or rectal stump leak in elective and emergency colorectal surgery? A single-center experience.

Anastomotic and rectal stump leaks are feared complications of colorectal surgery. Diverting stomas are commonly used to protect low rectal anastomoses but can have adverse effects. Studies have reported favorable outcomes for transanal drainage devices instead of diverting stomas. We describe our use of the Heald anal stent and its potential impact in reducing anastomotic or rectal stump leak after elective or emergency colorectal surgery. We performed a single-center retrospective analysis of patients in whom a Heald anal stent had been used to "protect" a colorectal anastomosis or a rectal stump, in an elective or emergency context, for benign and malignant pathology. Intraoperative and postoperative outcomes were reviewed using clinical and radiological records. The Heald anal stent was used in 93 patients over 4 years. Forty-six cases (49%) had a colorectal anastomosis, and 47 (51%) had an end stoma with a rectal stump. No anastomotic or rectal stump leaks were recorded. We recommend the Heald anal stent as a simple and affordable adjunct that may decrease anastomotic and rectal stump leak by reducing intraluminal pressure through drainage of fluid and gas.

Detection and characterization of colorectal cancer by autofluorescence lifetime imaging on surgical specimens.

Colorectal cancer (CRC) ranks among the most prevalent malignancies worldwide, driving a quest for comprehensive characterization methods. We report a characterization of the ex vivo autofluorescence lifetime fingerprint of colorectal tissues obtained from 73 patients that underwent surgical resection. We specifically target the autofluorescence characteristics of collagens, reduced nicotine adenine (phosphate) dinucleotide (NAD(P)H), and flavins employing a fiber-based dual excitation (375 nm and 445 nm) optical imaging system. Autofluorescence-derived parameters obtained from normal tissues, adenomatous lesions, and adenocarcinomas were analyzed considering the underlying clinicopathological features. Our results indicate that differences between tissues are primarily driven by collagen and flavins autofluorescence parameters. We also report changes in the autofluorescence parameters associated with NAD(P)H that we tentatively attribute to intratumoral heterogeneity, potentially associated to the presence of distinct metabolic subpopulations. Changes in autofluorescence signatures of malignant tumors were also observed with lymphatic and venous invasion, differentiation grade, and microsatellite instability. Finally, we characterized the impact of radiative treatment in the autofluorescence fingerprints of rectal tissues and observed a generalized increase in the mean lifetime of radiated adenocarcinomas, which is suggestive of altered metabolism and structural remodeling. Overall, our preliminary findings indicate that multiparametric autofluorescence lifetime measurements have the potential to significantly enhance clinical decision-making in CRC, spanning from initial diagnosis to ongoing management. We believe that our results will provide a foundational framework for future investigations to further understand and combat CRC exploiting autofluorescence measurements.

Preoperative high-resolution magnetic resonance imaging can identify good prognosis stage I, II, and III rectal cancer best managed by surgery alone: a prospective, multicenter, European study.

OBJECTIVE: To assess local recurrence, disease-free survival, and overall survival in magnetic resonance imaging (MRI)-predicted good prognosis tumors treated by surgery alone. BACKGROUND: The MERCURY study reported that high-resolution MRI can accurately stage rectal cancer. The routine policy in most centers involved in the MERCURY study was primary surgery alone in MRI-predicted stage II or less and in MRI "good prognosis" stage III with selective avoidance of neoadjuvant therapy. PATIENTS AND METHODS: Data were collected prospectively on all patients included in the MERCURY study who were staged as MRI-defined "good" prognosis tumors. "Good" prognosis included MRI-predicted safe circumferential resection margins, with MRI-predicted T2/T3a/T3b (less than 5 mm spread from muscularis propria), regardless of MRI N stage. None received preoperative or postoperative radiotherapy. Overall survival, disease-free survival, and local recurrence were calculated. RESULTS: Of 374 patients followed up in the MERCURY study, 122 (33%) were defined as "good prognosis" stage III or less on MRI. Overall and disease-free survival for all patients with MRI "good prognosis" stage I, II and III disease at 5 years was 68% and 85%, respectively. The local recurrence rate for this series of patients predicted to have a good prognosis tumor on MRI was 3%. CONCLUSIONS: The preoperative identification of good prognosis tumors using MRI will allow stratification of patients and better targeting of preoperative therapy. This study confirms the ability of MRI to select patients who are likely to have a good outcome with primary surgery alone.

MRI predictive factors for long-term outcomes of low rectal tumours.

BACKGROUND: Low rectal cancers have poor outcomes. It has been suggested that low tumours are biologically more aggressive and tend to be more locally advanced at presentation. Pre-operative identification of prognostic factors will enable use of selective neoadjuvant therapies and possibly increase sphincter-sparing rates where oncologically safe. METHODS: A subset of 101 patients with low rectal cancer (within 5 cm of the anal verge) in a multicentre trial were studied. MRI images were reviewed by a senior radiologist, blinded to outcome. MRI-predicted tumour spread and MRI tumour regression grade (TRG) were analysed for 5-year recurrence and survival rates using a Cox regression model. RESULTS: On univariate analysis, advanced MRI low rectal tumour stage correlated with greater incidence of recurrence (p=0.013) and death (p=0.029) compared with earlier stage tumours. Good MRI TRG score (good response to pre-operative therapy) correlated with significantly reduced tumour recurrence rates (p=0.008) and increased survival (p=0.008) versus the poor MRI TRG score group. On multivariate analysis, good MRI TRG score was associated with reduced recurrence (p=0.003) but not survival rates. CONCLUSIONS: This study confirms that MRI can be used to predict patients at increased risk of recurrence following surgery in low rectal cancer. This information can be used to direct pre-operative therapies and plan operative strategies. This is the first study to confirm the association between MRI TRG and long-term outcome. Poor response to neoadjuvant therapy can be used to plan use of further therapies prior to surgery to attempt to improve outcome.

Deep pelvic anatomy revisited for a description of crucial steps in extralevator abdominoperineal excision for rectal cancer.

BACKGROUND: Extralevator abdominoperineal excision results in superior oncologic outcome for advanced low rectal cancer. The exact definition of surgical resection planes is pivotal to achieving negative circumferential resection margins. OBJECTIVE: This study aims to describe the surrounding anatomical structures that are at risk for inadvertent damage during extralevator abdominoperineal excision. DESIGN AND SETTING: Joint surgical and macroanatomical dissection was performed in a university laboratory of clinical anatomy. METHODS: A stepwise dissection study was conducted according to the technique of extralevator abdominoperineal excision by abdominal and perineal approaches in 4 human cadaveric pelvises. Muscular, fascial, tendinous, and neural structures were carefully exposed and related to the corresponding surgical resection planes. RESULTS: In addition to the autonomic nerves to be identified and preserved during total mesorectal excision, further structures endangered during extralevator abdominoperineal excision can be clearly identified. Terminal pudendal nerve branches come close to the surgical resection plane at the outer surface of the puborectal sling. Likewise, the pelvic plexus and its neurovascular bundles embedded within the parietal pelvic fascia extend close to the apex of the prostate where the parietal pelvic fascia has to be divided. These neural structures converge in the region of the perineal body, an area that provides no "self-opening" planes for surgical dissection. Thus, the necessity to sharply detach the anorectal specimen anteriorly from the perineal body and the superficial transverse perineal muscle bears the risk of both inadvertent damage of the aforementioned anatomical structures and perforation of the specimen. LIMITATIONS: The study focused primarily on the macroscopic topography relevant to the surgical procedure, so that previously published histologic examinations were not performed. CONCLUSION: The present anatomical dissection study highlights those anatomical landmarks that require clear identification for the successful achievement of both negative circumferential resection margins and preservation of urogenital functions during extralevator abdominoperineal excision.

Can a novel MRI staging system for low rectal cancer aid surgical planning?

BACKGROUND: Low rectal cancers are associated with worse outcomes in comparison with mid and upper rectal tumors. OBJECTIVE: This study aimed to assess the predictive accuracy of MRI in identifying the correct surgical approach based on the mesorectal and extralevator planes. DESIGN: This study involved the retrospective analysis of MRI and histopathology data of 33 patients with low rectal cancer, with the use of an anatomically based staging system. Three radiologists reported on the available surgical planes of excision based on the predicted relationship of tumor to key anatomical features. MRI-predicted planes of excision were then compared with the histopathological planes actually required, with the use of the same staging criteria. SETTINGS: The study was conducted at 4 English district general hospitals. PATIENTS: Unselected patients with low rectal cancer, all of whom were participants in a multicenter study, were eligible for this study. MAIN OUTCOME MEASURES: : The main outcome measured was the accuracy of operative plane prediction on MRI. RESULTS: : On pathological analysis, the mesorectal plane would have been sufficient to achieve a clear margin in 28 of 33 (84.9%) of cases. The extralevator plane was required in 5 of 33 (15.1%). Planes were correctly predicted by MRI in 29 of 33 cases by radiologist 1 and 24 of 33 cases by radiologists 2 and 3 with an accuracy of 87.9% and 72.7%. Overstaging (extralevator plane predicted when a mesorectal plane would have sufficed) occurred in 3 of 33 and 7 of 33 cases. Understaging (mesorectal plane predicted when an extralevator plane was required) occurred in 1 of 33 and 2 of 33 cases. The positive and negative predictive values of MRI in determining the histopathological plane of excision required were 57% and 96% for radiologist 1 and 30% and 91% for radiologists 2 and 3. LIMITATIONS: This study was limited by its retrospective nature and its relatively small patient numbers. No account was taken of postoperative function when recommending the surgical plane. CONCLUSIONS: This supports an anatomically based MRI staging system for low rectal cancer to predict the planes of surgical excision. This may help to reduce margin positivity and to improve outcome in patients with low rectal cancer.

Transanal Transection and Single-Stapled Anastomosis (TTSS): A comparison of anastomotic leak rates with the double-stapled technique and with transanal total mesorectal excision (TaTME) for rectal cancer.

BACKGROUND: in the literature on rectal cancer (RC) surgery many studies have focused on the quality of total mesorectal excision (TME) dissection, while there is a scarcity of comparative data on transection and anastomosis. No anastomosis has so far proved to be superior to any other. The aim of this study was to compare anastomotic leak (AL) rates between conventional laparoscopic double-stapled (DS), transanal total mesorectal excision (TaTME) and Transanal Transection and Single-Stapled anastomosis (TTSS) techniques. METHODS: consecutive mid-low RC patients undergoing elective laparoscopic TME with stapled anastomosis and protective stoma, by either DS, TaTME or TTSS techniques were retrieved from a prospectively collected database. RESULTS: 127 DS; 100 TaTME and 50 TTSS were included. Demographics, distance of the tumor from anal verge and neoadjuvant therapy were comparable. Operative time was longer in TaTME over DS and TTSS (p < 0.0001). More 90-days complications occurred in DS group vs TTSS (p = 0.029). The AL rate was 17.5% in DS, 6% in TaTME and 2% in TTSS group (p = 0.005). AL grade was: one B (2%) in TTSS; 2 grade B (2%) and 4 grade C (4%) in TaTME; 6 grade A (4.7%), 7 grade B (5.5%) and 9 grade C (7.1%) in DS group. Reintervention rate after AL was higher in DS group over TTSS (12.6% vs 2%; p = 0.003). The rate of stoma closure, pathology data and margin positivity did not differ. CONCLUSIONS: TTSS strategy is feasible, safe and leads to very low AL rates after TME for RC.

Patients with low rectal cancer treated by abdominoperineal excision have worse tumors and higher involved margin rates compared with patients treated by anterior resection.

PURPOSE: Patients with low rectal cancer have worse outcomes compared to those with upper rectal cancer. Reports suggest that low anterior resection may be oncologically superior to abdominoperineal excision, although no good evidence exists to support this. We looked at a recent series of patients with low rectal cancer to explore some of the issues. METHODS: We analyzed 153 patients from the MERCURY study with low rectal cancer (