Transanal total mesorectal excision (taTME) for rectal cancer: beyond the learning curve

Transanal vs Laparoscopic Total Mesorectal Excision and 3-Year Disease-Free Survival in Rectal Cancer: The TaLaR Randomized Clinical Trial

Importance

Previous studies have demonstrated the advantages of short-term histopathological outcomes and complications associated with transanal total mesorectal excision (TME) compared with laparoscopic TME. However, the long-term oncological outcomes of transanal TME remain ambiguous. This study aims to compare 3-year disease-free survival of transanal TME with laparoscopic TME.

Objective

To evaluate 3-year disease-free survival between transanal TME and laparoscopic TME in patients with rectal cancer.

Design, Setting, and Participants

This randomized, open-label, noninferiority, phase 3 clinical trial was performed in 16 different centers in China. Between April 2016 and June 2021, a total of 1115 patients with clinical stage I to III mid-low rectal cancer were enrolled. The last date of participant follow-up was in June 2024.

Interventions

Participants were randomly assigned in a 1:1 ratio before their surgical procedure to undergo either transanal TME (n = 558) or laparoscopic TME (n = 557).

Main Outcomes and Measures

The primary end point was 3-year disease-free survival, with a noninferiority margin of -10% for the comparison between transanal TME and laparoscopic TME. Secondary outcomes included 3-year overall survival and 3-year local recurrence.

Results

In the primary analysis set, the median patient age was 60 years. A total of 692 male and 397 female patients were included in the analysis. Three-year disease-free survival was 82.1% (97.5% CI, 78.4%-85.8%) for the transanal TME group and 79.4% (97.5% CI, 75.6%-83.4%) for the laparoscopic TME group, with a difference of 2.7% (97.5% CI, -3.0% to 8.1%). The lower tail of a 2-tailed 97.5% CI for the group difference in 3-year disease-free survival was above the noninferiority margin of -10 percentage points. Furthermore, the 3-year local recurrence was 3.6% (95% CI, 2.0%-5.1%) for transanal TME and 4.4% (95% CI, 2.6%-6.1%) for laparoscopic TME. Three-year overall survival was 92.6% (95% CI, 90.4%-94.8%) for transanal TME and 90.7% (95% CI, 88.3%-93.2%) for laparoscopic TME.

Conclusions and Relevance

In patients with mid-low rectal cancer, 3-year disease-free survival for transanal TME was noninferior to that of laparoscopic TME.

Trial Registration

ClinicalTrials.gov Identifier: NCT02966483.

The integration of artificial intelligence in robotic surgery: A narrative review

BACKGROUND

The rise of high-definition imaging and robotic surgery has independently been associated with improved postoperative outcomes. However, steep learning curves and finite human cognitive ability limit the facility in imaging interpretation and interaction with the robotic surgery console interfaces. This review presents innovative ways in which artificial intelligence integrates preoperative imaging and surgery to help overcome these limitations and to further advance robotic operations.

METHODS

PubMed was queried for "artificial intelligence," "machine learning," and "robotic surgery." From the 182 publications in English, a further in-depth review of the cited literature was performed.

RESULTS

Artificial intelligence boasts efficiency and proclivity for large amounts of unwieldy and unstructured data. Its wide adoption has significant practice-changing implications throughout the perioperative period. Assessment of preoperative imaging can augment preoperative surgeon knowledge by accessing pathology data that have been traditionally only available postoperatively through analysis of preoperative imaging. Intraoperatively, the interaction of artificial intelligence with augmented reality through the dynamic overlay of preoperative anatomical knowledge atop the robotic operative field can outline safe dissection planes, helping surgeons make critical real-time intraoperative decisions. Finally, semi-independent artificial intelligence-assisted robotic operations may one day be performed by artificial intelligence with limited human intervention.

CONCLUSION

As artificial intelligence has allowed machines to think and problem-solve like humans, it promises further advancement of existing technologies and a revolution of individualized patient care. Further research and ethical precautions are necessary before the full implementation of artificial intelligence in robotic surgery.

Oncologic outcomes following transanal total mesorectal excision: the United States experience

AIM

The benefits and short-term outcomes of transanal total mesorectal excision (taTME) for rectal cancer have been demonstrated previously, but questions remain regarding the oncologic outcomes following this challenging procedure. The purpose of this study was to analyze the oncologic outcomes following taTME at high-volume centers in the USA.

METHODS

This was a multicenter, retrospective observational study of 8 tertiary care centers. All consecutive taTME cases for primary rectal cancer performed between 2011 and 2020 were included. Clinical, histopathologic, and oncologic data were analyzed. Primary endpoints were rate of local recurrence, distal recurrence, 3-year disease recurrence, and 3-year overall survival. Secondary endpoints included perioperative complications and TME specimen quality.

RESULTS

A total of 391 patients were included in the study. The median age was 57 years (IQR: 49, 66), 68% of patients were male, and the median BMI was 27.4 (IQR: 24.1, 31.0). TME specimen was complete or near complete in 94.5% of cases and the rates of positive circumferential radial margin and distal resection margin were 2.0% and 0.3%, respectively. Median follow-up time was 30.7 months as calculated using reverse-KM estimator (CI 28.1-33.8) and there were 9 cases (2.5%) of local recurrence not accounting for competing risk. The 3-year estimated rate of disease recurrence was 19% (CI 15-25%) and the 3-year estimated overall survival was 90% (CI 87-94%).

CONCLUSION

This large multicenter study confirms the oncologic safety and perioperative benefits of taTME for rectal cancer when performed by experienced surgeons at experienced referral centers.

Local Recurrence-Free Survival After TaTME: A Canadian Institutional Experience

BACKGROUND

Transanal total mesorectal excision is a novel surgical treatment for mid to low rectal cancers. Norwegian population data have raised concerns about local recurrence in patients treated with transanal total mesorectal excision.

OBJECTIVE

This study aimed to analyze local recurrence and disease-free survival in patients treated by transanal total mesorectal excision for rectal cancer at a high-volume tertiary center.

DESIGN

This retrospective study used a prospectively maintained institutional transanal total mesorectal excision database. Patient demographics, treatment, and outcomes data were analyzed. Local recurrence, disease-free survival, and overall survival were analyzed using Kaplan-Meier analysis.

SETTINGS

The study was conducted at a single academic institution in Vancouver, Canada.

PATIENTS

All patients treated by transanal total mesorectal excision for rectal adenocarcinoma between 2014 and 2022 were included.

MAIN OUTCOME MEASURES

The primary outcome was local recurrence-free survival.

RESULTS

Between 2014 and 2022, 306 patients were treated by transanal total mesorectal excision at St. Paul's Hospital. Of these, 279 patients met the inclusion criteria. The mean age was 62 years (SD ± 12.3), and 66.7% of patients were men. Restorative resection was achieved in 97.5% of patients, with a conversion rate from laparoscopic to open surgery of 6.8%. The composite optimal pathological outcome was 93.9%. The median follow-up was 26 months (interquartile range, 12-47), and 82.8% of patients achieved reestablishment of GI continuity to date. The overall local recurrence rate was 4.7% (n = 13). The estimated 2-year local recurrence-free survival rate was 95.0% (95% CI, 92-98) and the estimated 5-year local recurrence-free survival rate was 94.5% (95% CI, 91-98).

LIMITATIONS

Limitations include the retrospective nature of the study and the generalizability of a Canadian population.

CONCLUSIONS

Recent European data have challenged the presumed oncologic safety of transanal total mesorectal excision. Although the learning curve for this procedure is challenging and poor outcomes are associated with low volume, this high-volume single-center study confirms acceptable oncologic outcomes consistent with the current standard. See Video Abstract .

SOBREVIDA SIN RECIDIVA DESPUS DE TATME EXPERIENCIA INSTITUCIONAL CANADIENSE

ANTECEDENTES:La excisión total del mesorecto por vía transanal es un tratamiento quirúrgico novedoso para los cánceres de recto medio a bajo. Estudios sobre la población noruega han generado preocupación debido a la recidiva local en pacientes tratados con excisión total del mesorecto por vía transanal.OBJETIVO:Nuestra finalidad fué de analizar la recidiva local y la sobrevida libre de enfermedad en pacientes tratados mediante la excisión total del mesorecto por vía transanal, debido a un cáncer de recto en un centro terciario de alto volúmen.DISEÑO:El presente estudio retrospectivo, utiliza una base de datos institucional sobre la excisión total del mesorecto por vía transanal mantenida prospectivamente. Se analizaron los datos demográficos, de tratamiento y los resultados de los pacientes sometidos a la técnica mencionada. La recidiva local, la sobrevida libre de enfermedad y la sobrevida global se analizaron mediante el modelo de Kaplan-Meier.AJUSTES:El estudio se llevó a cabo en una sola institución académica en Vancouver, Canadá.PARTICIPANTES:Se incluyeron todos los pacientes tratados mediante excisión total del mesorecto por vía transanal causado por adenocarcinomas de recto entre 2014 y 2022.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario fue la sobrevida libre de recidiva local.RESULTADOS:Entre 2014 y 2022, 306 pacientes fueron tratados mediante la excisión total del mesorecto por vía transanal en el Hospital St. Paul. De estos, 279 pacientes cumplieron los criterios de inclusión. La edad media fue de 62 años (DE ± 12,3) y el 66,7% de los pacientes eran varones. La resección restauradora se logró en el 97,5% de los pacientes con una tasa de conversión de cirugía laparoscópica en laparotomía del 6,8%. El resultado patológico óptimo combinado fué del 93,9%. La mediana de seguimiento fue de 26 meses (rango intercuartil 12-47) y el 82,8% logró el restablecimiento de la continuidad gastrointestinal hasta la fecha. La tasa global de recidiva local fué del 4,7% (n = 13). La sobrevida libre de recidiva local estimada a los 2 años fué del 95,0% (IC del 95%: 92-98) y del 94,5% a los 5 años (IC del 95%: 91-98).LIMITACIONES:Las limitaciones incluyen la naturaleza retrospectiva del estudio y la generalización de una población canadiense.CONCLUSIONES:Datos europeos recientes han cuestionado la supuesta seguridad oncológica de la excisión total del mesorecto por vía transanal. Si bien la curva de aprendizaje de este procedimiento es muy desafiante y los malos resultados se asocian con un volumen bajo, el presente estudio, unicéntrico de gran volumen confirma los resultados oncológicos aceptables consistentes con el estándar actual. (Traducción-Dr. Xavier Delgadillo ).

Differential Effects of Race, Socioeconomic Status, and Insurance on Disease-Specific Survival in Rectal Cancer

BACKGROUND

National Comprehensive Cancer Network guideline adherence improves cancer outcomes. In rectal cancer, guideline adherence is distributed differently by race/ethnicity, socioeconomic status, and insurance.

OBJECTIVE

This study aimed to determine the independent effects of race/ethnicity, socioeconomic status, and insurance status on rectal cancer survival after accounting for differences in guideline adherence.

DESIGN

This was a retrospective study.

SETTINGS

The study was conducted using the California Cancer Registry.

PATIENTS

This study included patients aged 18 to 79 years diagnosed with rectal adenocarcinoma between January 1, 2004, and December 31, 2017, with follow-up through November 30, 2018. Investigators determined whether patients received guideline-adherent care.

MAIN OUTCOME MEASURES

ORs and 95% CIs were used for logistic regression to analyze patients receiving guideline-adherent care. Disease-specific survival analysis was calculated using Cox regression models.

RESULTS

A total of 30,118 patients were examined. Factors associated with higher odds of guideline adherence included Asian and Hispanic race/ethnicity, managed care insurance, and high socioeconomic status. Asians (HR, 0.80; 95% CI, 0.72-0.88; p < 0.001) and Hispanics (HR, 0.91; 95% CI, 0.83-0.99; p = 0.0279) had better disease-specific survival in the nonadherent group. Race/ethnicity were not factors associated with disease-specific survival in the guideline adherent group. Medicaid disease-specific survival was worse in both the nonadherent group (HR, 1.56; 95% CI, 1.40-1.73; p < 0.0001) and the guideline-adherent group (HR, 1.18; 95% CI, 1.08-1.30; p = 0.0005). Disease-specific survival of the lowest socioeconomic status was worse in both the nonadherent group (HR, 1.42; 95% CI, 1.27-1.59) and the guideline-adherent group (HR, 1.20; 95% CI, 1.08-1.34).

LIMITATIONS

Limitations included unmeasured confounders and the retrospective nature of the review.

CONCLUSIONS

Race, socioeconomic status, and insurance are associated with guideline adherence in rectal cancer. Race/ethnicity was not associated with differences in disease-specific survival in the guideline-adherent group. Medicaid and lowest socioeconomic status had worse disease-specific survival in both the guideline nonadherent group and the guideline-adherent group. See Video Abstract at http://links.lww.com/DCR/B954 .

EFECTOS DIFERENCIALES DE LA RAZA, EL NIVEL SOCIOECONMICO COBERTURA SOBRE LA SUPERVIVENCIA ESPECFICA DE LA ENFERMEDAD EN EL CNCER DE RECTO

ANTECEDENTES: El cumplimiento de las guías de la National Comprehensive Cancer Network mejora los resultados del cáncer. En el cáncer de recto, el cumplimiento de las guías se distribuye de manera diferente según la raza/origen étnico, nivel socioeconómico y el cobertura médica.OBJETIVO: Determinar los efectos independientes de la raza/origen étnico, el nivel socioeconómico y el estado de cobertura médica en la supervivencia del cáncer de recto después de tener en cuenta las diferencias en el cumplimiento de las guías.DISEÑO: Este fue un estudio retrospectivo.ENTORNO CLINICO: El estudio se realizó utilizando el Registro de Cáncer de California.PACIENTES: Pacientes de 18 a 79 años diagnosticados con adenocarcinoma rectal entre el 1 de enero de 2004 y el 31 de diciembre de 2017 con seguimiento hasta el 30 de noviembre de 2018. Los investigadores determinaron si los pacientes recibieron atención siguiendo las guías.PRINCIPALES MEDIDAS DE RESULTADO: Se utilizaron razones de probabilidad e intervalos de confianza del 95 % para la regresión logística para analizar a los pacientes que recibían atención con adherencia a las guías. El análisis de supervivencia específico de la enfermedad se calculó utilizando modelos de regresión de Cox.RESULTADOS: Se analizaron un total de 30.118 pacientes. Los factores asociados con mayores probabilidades de cumplimiento de las guías incluyeron raza/etnicidad asiática e hispana, seguro de atención administrada y nivel socioeconómico alto. Los asiáticos e hispanos tuvieron una mejor supervivencia específica de la enfermedad en el grupo no adherente HR 0,80 (95 % CI 0,72 - 0,88, p < 0,001) y HR 0,91 (95 % CI 0,83 - 0,99, p = 0,0279). La raza o el origen étnico no fueron factores asociados con la supervivencia específica de la enfermedad en el grupo que cumplió con las guías. La supervivencia específica de la enfermedad de Medicaid fue peor tanto en el grupo no adherente HR 1,56 (IC del 95 % 1,40 - 1,73, p < 0,0001) como en el grupo adherente a las guías HR 1,18 (IC del 95 % 1,08 - 1,30, p = 0,0005). La supervivencia específica de la enfermedad del nivel socioeconómico más bajo fue peor tanto en el grupo no adherente HR 1,42 (IC del 95 %: 1,27 a 1,59) como en el grupo adherente a las guías HR 1,20 (IC del 95 %: 1,08 a 1,34).LIMITACIONES: Las limitaciones incluyeron factores de confusión no medidos y la naturaleza retrospectiva de la revisión.CONCLUSIONES: La raza, el nivel socioeconómico y cobertura médica están asociados con la adherencia a las guías en el cáncer de recto. La raza/etnicidad no se asoció con diferencias en la supervivencia específica de la enfermedad en el grupo que cumplió con las guías. Medicaid y el nivel socioeconómico más bajo tuvieron peor supervivencia específica de la enfermedad tanto en el grupo que no cumplió con las guías como en los grupos que cumplieron. Consulte Video Resumen en http://links.lww.com/DCR/B954 . (Traducción- Dr. Francisco M. Abarca-Rendon).

Recurrence following transanal total mesorectal excision for rectal cancer: a monocentric retrospective series of technically difficult cases

PURPOSE

Transanal total mesorectal excision (TaTME) has been proposed to overcome surgical difficulties encountered during rectal resection, especially for patients having high body mass index or low rectal cancer. The aim of this study was to evaluate oncologic outcomes following TaTME.

METHODS

This retrospective study included all consecutive patients with rectal cancer who had a TaTME from 2013 to 2019. The main outcome was the incidence of locoregional recurrence by the end of the follow-up period.

RESULTS

Among a total of 81 patients, 96.3% were male, and their mean age was 63±9 years. The mean body mass index was 30.3±5.7 kg/m2, and the median distance from tumor to anal verge was 5.0 cm (interquartile range [IQR], 4.0-6.0 cm). Most patients had a low anterior resection performed (n=80, 98.8%) with a diverting ileostomy (n=64, 79.0%). Distal and circumferential resection margins were positive in 2.5% and 6.2% of patients, respectively. Total mesorectal excision was complete or near complete in 95.1% of patients. A successful resection was achieved in 72 patients (88.9%). After a median follow-up of 27.5 months (IQR, 16.7-48.1 months), 4 patients (4.9%) experienced locoregional recurrence. Anastomotic leaks were observed in 21 patients (25.9%). At the end of the follow-up, 69 patients (85.2%) were stoma-free.

CONCLUSION

TaTME was associated with acceptable oncological outcomes, including low locoregional recurrence rates in selected patients with low rectal cancer. Although associated with a high incidence of postoperative morbidities, the use of TaTME enabled a high rate of successful sphincter-saving procedures in selected patients who posed a technical challenge.

Outcomes of open vs laparoscopic vs robotic vs transanal total mesorectal excision (TME) for rectal cancer: a network meta-analysis

BACKGROUND

Total mesorectal excision (TME) for rectal cancer can be achieved using open (OpTME), laparoscopic (LapTME), robotic (RoTME), or transanal techniques (TaTME). However, the optimal approach for access remains controversial. The aim of this network meta-analysis was to assess operative and oncological outcomes of all four surgical techniques.

METHODS

Ovid MEDLINE, EMBASE, and PubMed databases were searched systematically from inception to September 2020, for randomised controlled trials (RCTs) comparing any two TME surgical techniques. A network meta-analysis using a Bayesian random-effects framework and mixed treatment comparison was performed. Primary outcomes were the rate of clear circumferential resection margin (CRM), defined as > 1 mm from the closest tumour to the cut edge of the tissue, and completeness of mesorectal excision. Secondary outcomes included radial and distal resection margin distance, postoperative complications, locoregional recurrence, disease-free survival, and overall survival. Surface under cumulative ranking (SUCRA) was used to rank the relative effectiveness of each intervention for each outcome. The higher the SUCRA value, the higher the likelihood that the intervention is in the top rank or one of the top ranks.

RESULTS

Thirty-two RCTs with a total of 6151 patients were included. Compared with OpTME, there was no difference in the rates of clear CRM: LapTME RR = 0.99 (95% (Credible interval) CrI 0.97-1.0); RoTME RR = 1.0 (95% CrI 0.96-1.1); TaTME RR = 1.0 (95% CrI 0.96-1.1). There was no difference in the rates of complete mesorectal excision: LapTME RR = 0.98 (95% CrI 0.98-1.1); RoTME RR = 1.1 (95% CrI 0.98-1.4); TaTME RR = 1.0 (95% CrI 0.91-1.2). RoTME was associated with improved distal resection margin distance compared to other techniques (SUCRA 99%). LapTME had a higher rate of conversion to open surgery when compared with RoTME: RoTME RR = 0.23 (95% CrI 0.034-0.70). Length of stay was shortest in RoTME compared to other surgical approaches: OpTME mean difference in days (MD) 3.3 (95% CrI 0.12-6.0); LapTME MD 1.7 (95% CrI - 1.1-4.4); TaTME MD 1.3 (95% CrI - 5.2-7.4). There were no differences in 5-year overall survival (LapTME HR 1.1, 95% CrI 0.74, 1.4; TaTME HR 1.7, 95% CrI 0.79, 3.4), disease-free survival rates (LapTME HR 1.1, 95% CrI 0.76, 1.4; TaTME HR 1.1, 95% CrI 0.52, 2.4), or anastomotic leakage (LapTME RR = 0.92 (95% CrI 0.63, 1.1); RoTME RR = 1.0 (95% CrI 0.48, 1.8); TaTME RR = 0.53 (95% CrI 0.19, 1.2). The overall quality of evidence as per Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessments across all outcomes including primary and secondary outcomes was deemed low.

CONCLUSIONS

In selected patients eligible for a RCT, RoTME achieved improved distal resection margin distance and a shorter length of hospital stay. No other differences were observed in oncological or recovery parameters between (OpTME), laparoscopic (LapTME), robotic (RoTME), or trans-anal TME (TaTME). However, the overall quality of evidence across all outcomes was deemed low.

Learning Curve for Transanal Total Mesorectal Excision for Low Rectal Malignancy

BACKGROUND

Although transanal total mesorectal excision (TaTME) is a promising treatment for low rectal cancer, it is considered technically demanding, and the number of cases required to become proficient in TaTME remains unknown. The purpose of this study was to assess the TaTME learning curve based on the total mesorectal excision completion time.

STUDY DESIGN

This retrospective analysis comprised 128 individuals who received TaTME between September 2016 and December 2021. The cumulative sum method was used to generate the learning curve. The duration of the procedure from the beginning to the end of the circumferential rendezvous was used to define the total mesorectal excision completion time.

RESULTS

The learning curve consists of 3 phases: phase I (learning phase: cases 1 to 38), phase II (consolidation phase: cases 39 to 70), and phase III (maturing phase: cases 71 to 128). As the phases varied, both the overall operative time and total mesorectal excision completion time decreased considerably. Through the 3 phases of TaTME, intraoperative adverse events decreased, and in phase III, none occurred. Only 1 instance of local recurrence occurred during phase III, and none occurred during phase I or II.

CONCLUSIONS

After 70 operations, the surgeon could join the mastery phase of TaTME based on the total mesorectal excision completion time. After the mastering phase began, there were no intraoperative negative occurrences. From the beginning, the oncological safety could be guaranteed.

Impact of the approach on conversion to open surgery during minimally invasive restorative total mesorectal excision for rectal cancer

BACKGROUND

The aim of this study is to explore the impact of the approach on conversion in patients undergoing minimally invasive restorative total mesorectal excision within a single unit.

METHODS

A retrospective cohort study was conducted. Patients with rectal cancer undergoing minimally invasive restorative total mesorectal excision between January 2006 and June 2020 were included. Subjects were classified according to the presence or absence of conversion. Baseline variables and short-term outcomes were compared. Regression analyses were conducted to assess the relationship between the approach and conversion.

RESULTS

During the study period, 318 patients underwent a restorative proctectomy. Of these, 240 met the inclusion criteria. Robotic and laparoscopic approaches were undertaken in 147 (61.3%) and 93 (38.8%) cases, respectively. A transanal approach was utilised in 62 (25.8%) cases (58.1% in combination with a robotic transabdominal approach). Conversion to open surgery occurred in 30 cases (12.5%). Conversion was associated with an increased overall complication rate (P = 0.003), surgical complications (P = 0.009), superficial surgical site infections (P = 0.02) and an increased length of hospital stay (P = 0.006). Robotic and transanal approaches were both associated with decreased conversion rates. The multiple logistic regression analysis, however, showed that only a transanal approach was independently associated with a lower risk of conversion (OR 0.147, 0.023-0.532; P = 0.01), whilst obesity was an independent risk factor for conversion (OR 4.388, 1.852-10.56; P < 0.00).

CONCLUSIONS

A transanal component is associated with a reduced conversion rate in minimally invasive restorative total mesorectal excision, regardless of the transabdominal approach utilised. Larger studies will be required to confirm these findings and define which subgroup of patients could benefit from transanal component when a robotic approach is undertaken.

Transanal Total Mesorectal Excision (TaTME) versus Laparoscopic Total Mesorectal Excision for Lower Rectal Cancer: A Propensity Score-Matched Analysis

Studies have reported positive short-term and histopathological results of transanal total mesorectal excision (TaTME) for mid-low rectal cancer. The long-term oncological outcomes are diverse, and concerns regarding the high local recurrence (LR) rate of TaTME have recently increased. We retrospectively analyzed 298 consecutive patients who underwent Laparoscopic TME (LapTME) or TaTME between January 2015 and December 2019. Propensity score-matching (PSM) was performed with patients matched for demographics and stage. After PSM, 63 patients were included in each group. The TaTME group had a longer mean operative time (394 vs. 333 min, p < 0.001). The blood loss, diverting stoma rate, and conversion rate were similar. Postoperatively, TaTME and LapTME had compatible complications, recovery, and hospital stay. A similar specimen quality was detected in both groups. After a mean follow-up period of 41−47 months, TaTME had less LR than LapTME (9.5% vs. 23.8%, p = 0.031). The 3-year overall survival was 80.3% in the TaTME group and 73.6% in the LapTME group (p = 0.331). The 3-year disease-free survival (DFS) rate was 72.0% in the TaTME group and 56.6% in the LapTME group (p = 0.038). In conclusion, better DFS and fewer LR events were observed after TaTME; thus, TaTME can be considered a safe and feasible approach in patients with low rectal cancer.

Implementation of robot-assisted curative resection for rare anorectal tumours on the basis of individualised treatment

PURPOSE

To evaluate the validity of robot-assisted curative operation for rare anorectal tumours, characterised by biological heterogeneity and anatomical complexity.

METHODS

The present study evaluated 16 consecutive patients including three with anorectal squamous cell carcinoma (ARSCC), four with anorectal mucosal melanoma (ARMM), seven with anorectal neuroendocrine tumour (ARNET), and two with other types of anorectal tumours.

RESULTS

Of the three patients with ARSCC after chemoradiotherapy, two underwent abdominoperineal resection (APR), and one underwent ultralow anterior resection (uLAR)/total intersphincteric resection (ISR), surviving 56-76 months without recurrence. Of the four ARMM patients, APR and uLAR/total ISR were conducted in two patients, respectively, with variable survival outcomes. All seven patients with ARNET were treated with uLAR/ISR and LAR, surviving for 5-106 months to date.

CONCLUSIONS

Because most anorectal tumours are confined to the dermal and submucosal layers, robotic anorectal function preserving ISR is expected to achieve R0 resection.

Evaluation of the learning curve for conformal sphincter preservation operation in the treatment of ultralow rectal cancer

BACKGROUND

To investigate the learning curve of conformal sphincter preservation operation (CSPO) in the treatment of ultralow rectal cancer and to further explore the influencing factors of operation time.

METHODS

From August 2011 to April 2020, 108 consecutive patients with ultralow rectal cancer underwent CSPO by the same surgeon in the Department of Colorectal Surgery of Changhai Hospital. The moving average and cumulative sum control chart (CUSUM) curve were used to analyze the learning curve. The preoperative clinical baseline data, postoperative pathological data, postoperative complications, and survival data were compared before and after the completion of learning curve. The influencing factors of CSPO operation time were analyzed by univariate and multivariate analysis.

RESULTS

According to the results of moving average and CUSUM method, CSPO learning curve was divided into learning period (1-45 cases) and learning completion period (46-108 cases). There was no significant difference in preoperative clinical baseline data, postoperative pathological data, postoperative complications, and survival data between the two stages. Compared with the learning period, the operation time (P < 0.05), blood loss (P < 0.05), postoperative flatus and defecation time (P < 0.05), liquid diet time (P < 0.05), and postoperative hospital stay (P < 0.05) in the learning completion period were significantly reduced, and the difference was statistically significant. Univariate and multivariate analysis showed that distance of tumor from anal verge (≥ 4cm vs. < 4cm, P = 0.039) and T stage (T3 vs. T1-2, P = 0.022) was independent risk factors for prolonging the operation time of CSPO.

CONCLUSIONS

For surgeons with laparoscopic surgery experience, about 45 cases of CSPO are needed to cross the learning curve. At the initial stage of CSPO, beginners are recommended to select patients with ultralow rectal cancer whose distance of tumor from anal verge is less than 4 cm and tumor stage is less than T3 for practice, which can enable beginners to reduce the operation time, accumulate experience, build self-confidence, and shorten the learning curve on the premise of safety.

Surgical Training for Transanal Total Mesorectal Excision in a Live Animal Model: A Preliminary Experience

Background: In this preliminary experience, the feasibility and effectiveness of surgical training with an animal model for transanal total mesorectal excision (TaTME) were evaluated. Methods: The training was conducted in two experimental animal laboratories in Italy authorized by the Italian Ministry of Health, using female Danish Landrace pigs under the supervision of surgeons with extensive experience in TaTME, animal laboratory training and cadaver laboratory training. The procedure was divided into separate steps, and all the participants were guided step-by-step throughout the entirety of the procedure. Results: During all the editions of the animal laboratory, all the procedures were completed with no major damage to the anatomical structures or intraoperative death of the animals. Live animal tissue is very similar to human tissue, helping trainees improve their tactile feedback. The bleeding effect improved the value of the training and taught the participants how to address this complication. The lack of mesorectal tissue in pigs compared with humans was the main difference. Animal laboratories should not be considered alternatives to cadaver laboratories but as complementary training activities due to their effectiveness and lower costs. Conclusions: Surgical training in animal models for TaTME seems to be effective and could be an opportunity to improve training alongside the use of a cadaver laboratory and proctoring.

Computer-aided anatomy recognition in intrathoracic and -abdominal surgery: a systematic review

BACKGROUND

Minimally invasive surgery is complex and associated with substantial learning curves. Computer-aided anatomy recognition, such as artificial intelligence-based algorithms, may improve anatomical orientation, prevent tissue injury, and improve learning curves. The study objective was to provide a comprehensive overview of current literature on the accuracy of anatomy recognition algorithms in intrathoracic and -abdominal surgery.

METHODS

This systematic review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Pubmed, Embase, and IEEE Xplore were searched for original studies up until January 2022 on computer-aided anatomy recognition, without requiring intraoperative imaging or calibration equipment. Extracted features included surgical procedure, study population and design, algorithm type, pre-training methods, pre- and post-processing methods, data augmentation, anatomy annotation, training data, testing data, model validation strategy, goal of the algorithm, target anatomical structure, accuracy, and inference time.

RESULTS

After full-text screening, 23 out of 7124 articles were included. Included studies showed a wide diversity, with six possible recognition tasks in 15 different surgical procedures, and 14 different accuracy measures used. Risk of bias in the included studies was high, especially regarding patient selection and annotation of the reference standard. Dice and intersection over union (IoU) scores of the algorithms ranged from 0.50 to 0.98 and from 74 to 98%, respectively, for various anatomy recognition tasks. High-accuracy algorithms were typically trained using larger datasets annotated by expert surgeons and focused on less-complex anatomy. Some of the high-accuracy algorithms were developed using pre-training and data augmentation.

CONCLUSIONS

The accuracy of included anatomy recognition algorithms varied substantially, ranging from moderate to good. Solid comparison between algorithms was complicated by the wide variety of applied methodology, target anatomical structures, and reported accuracy measures. Computer-aided intraoperative anatomy recognition is an upcoming research discipline, but still at its infancy. Larger datasets and methodological guidelines are required to improve accuracy and clinical applicability in future research.

TRIAL REGISTRATION

PROSPERO registration number: CRD42021264226.

Quality Indicators of Transanal Total Mesorectal Excision (TaTME) for Rectal Cancer

Introduction Transanal total mesorectal excision (TaTME) has revolutionized the surgical techniques for lower-third rectal cancer. The aim of the present study was to analyze the outcomes of quality indicators of TaTME for rectal cancer compared with laparoscopic TME (LaTME).

Methods A cohort prospective study with 50 (14 female and 36 male) patients, with a mean age of 67 (range: 55.75 to 75.25) years, who underwent surgery for rectal cancer. In total, 20 patients underwent TaTME, and 30, LaTME. Every TaTME procedure was performed by experienced colorectal surgeons. The sample was divided into two groups (TaTME and LaTME), and the quality indicators of the surgery for rectal cancer were analyzed.

Results There were no statistically significant differences regarding the patients and the main characteristics of the tumor (age, gender, American Society of Anesthesiologists [ASA] score, body mass index [BMI], tumoral stage, neoadjuvant therapy, and distance from the tumor to the external anal margin) between the two groups. The rates of: postoperative morbidity (TaTME: 35%; LaTME: 30%; p = 0.763); mortality (0%); anastomotic leak (TaTME: 10%; LaTME: 13%; p = 0.722); wound infection (TaTME: 0%; LaTME: 3.3%; p = 0.409); reoperation (TaTME: 5%; LaTME: 6.6%; p = 0.808); and readmission (TaTME: 5%; LaTME: 0%; p = 0.400), as well as the length of the hospital stay (TaTME: 13.5 days; LaTME: 11 days; p = 0.538), were similar in both groups. There were no statistically significant differences in the rates of positive circumferential resection margin (TaTME: 5%; LaTME: 3.3%; p = 0.989) and positive distal resection margin (TaTME: 0%; LaTME: 3.3%; p = 0.400), the completeness of the TME (TaTME: 100%; LaTME: 100%), and the number of lymph nodes harvested (TaTME: 15; LaTME: 15.5; p = 0.882) between two groups.

Conclusion Transanal total mesorectal excision is a safe and feasible surgical procedure for middle/lower-third rectal cancer.

Transanal total mesorectal excision and transabdominal robotic surgery for rectal cancer: A retrospective study

BACKGROUND

Transabdominal robotic surgery and transanal total mesorectal excision (TaTME) are newly introduced strategies for rectal cancer. These procedures might have many advantages in rectal cancer treatment in terms of improving oncological and functional outcomes, especially in cases involving advanced cancer or technical difficulty. In the present study, we aimed to clarify the advantages and disadvantages of transabdominal robotic surgery and laparoscopic TaTME as a hybrid surgery for rectal cancer.

MATERIALS AND METHODS

We retrospectively evaluated six patients who underwent hybrid surgery for rectal cancer from August 2018 to April 2020. Both clinical and pathological outcomes were assessed.

RESULTS

Two patients showed circumferential margin involvement both before and after neoadjuvant therapy. Three patients were planned to undergo hybrid surgery with intersphincteric resection because of a narrow pelvis. One patient was planned to undergo hybrid surgery for a giant tumor of >10 cm. The median length of hospitalization was 17 days. No patients required conversion to an open procedure. All patients underwent formation of defunctioning ileostomies. Two patients had a stapled anastomosis and four had a hand-sewn coloanal anastomosis. Complications included one case of anastomotic leakage, which was managed conservatively with ultrasound- and computed tomography-guided drainage and antibiotics. Histological analysis revealed that all specimens had a negative radial margin and distal margin. The median number of lymph nodes harvested was 17.5. Two patients showed extensive lymph node metastases, including lateral node metastasis.

CONCLUSION

Hybrid surgery was performed safely and may improve oncological outcomes for rectal cancer. This technique has many potential benefits and would be alternative option in multimodal strategies for rectal cancer.

A systematic review and meta-analysis on complications of transanal total mesorectal excision

AIM

Transanal total mesorectal excision (TaTME) is a surgical approach for treating mid to low rectal cancer as well as other colorectal diseases. Since the procedure is difficult to master, perioperative complications of TaTME should be examined precisely, especially during the early implementation phase of this procedure. The primary aim of this review was to determine a pooled morbidity and anastomotic leakage (AL) rate after TaTME surgery, and the secondary aim was to show the completeness of reporting of complications among the included studies, as well as the correlation between completeness and reported incidence of complications.

METHOD

A systematic review of literature was conducted using Medline, Embase and Cochrane databases, searching for observational studies reporting on complications after TaTME. Studies published between 1 January 2010 and 15 October 2019 were included. Meta-analysis on the proportion of morbidity, AL and intraoperative complications was performed.

RESULTS

Forty-one studies (2446 TaTME cases), consisting of 27 noncomparative studies and 14 comparative studies, were included, after screening 1711 possible studies. The pooled rates of overall morbidity and AL were 30.0% (95% CI 26.4%-34.0%) and 6.8% (95% CI 5.2%-8.9%), respectively. Subgroup analysis showed that the morbidity rate in studies that reported 30-day results (35.5%; 95% CI 31.8%-39.4%) was significantly higher than the rate in studies that did not define the follow-up length for complications (23.4%; 95% CI 17.8%-30.1%; p = 0.003). The rates of intraoperative urethral injury, rectal injury, vaginal injury and bladder injury were 0.3% (95% CI 0.1%-1.7%), 0.4% (95% CI 0.1%-2.2%), 0.3% (95% CI 0.1%-0.8%) and 0.3% (95% CI 0.1%-1.7%), respectively.

CONCLUSION

This meta-analysis shows that pooled perioperative complication rates were within acceptable ranges. However, the significant difference in overall morbidity rate between the studies with 30-day results and the studies without a specified follow-up time, indicates a large under-reporting of complications in many studies.

Predictors of Positive Circumferential Resection Margin in Rectal Cancer: A Current Audit of the National Cancer Database

BACKGROUND

Positive circumferential resection margin is a predictor of local recurrence and worse survival in rectal cancer. National programs aimed to improve rectal cancer outcomes were first created in 2011 and continue to evolve. The impact on circumferential resection margin during this time frame has not been fully evaluated in the United States.

OBJECTIVE

The purpose of this study was to determine the incidence and predictors of positive circumferential resection margin after rectal cancer resection, across patient, provider, and tumor characteristics.

DESIGN

This was a retrospective cohort study.

SETTINGS

The study was conducted using the National Cancer Database, 2011-2016.

PATIENTS

Adults who underwent proctectomy for pathologic stage I to III rectal adenocarcinoma were included.

MAIN OUTCOME MEASURES

Rate and predictors of positive circumferential resection margin, defined as resection margin ≤1 mm, were measured.

RESULTS

Of 52,620 cases, circumferential resection margin status was reported in 90% (n = 47,331) and positive in 18.4% (n = 8719). Unadjusted analysis showed that patients with positive circumferential resection margin were more often men, had public insurance and shorter travel, underwent total proctectomy via open and robotic approaches, and were treated in Southern and Western regions at integrated cancer networks (all p < 0.001). Multivariate analysis noted that positive proximal and/or distal margin on resected specimen had the strongest association with positive circumferential resection margin (OR = 15.6 (95% CI, 13.6-18.1); p < 0.001). Perineural invasion, total proctectomy, robotic approach, neoadjuvant chemoradiation, integrated cancer network, advanced tumor size and grade, and Black race had increased risk of positive circumferential resection margin (all p < 0.050). Laparoscopic approach, surgery in North, South, and Midwest regions, greater hospital volume and travel distance, lower T-stage, and higher income were associated with decreased risk (all p < 0.028).

LIMITATIONS

This was a retrospective cohort study with limited variables available for analysis.

CONCLUSIONS

Despite creation of national initiatives, positive circumferential resection margin rate remains an alarming 18.4%. The persistently high rate with predictors of positive circumferential resection margin identified calls for additional education, targeted quality improvement assessments, and publicized auditing to improve rectal cancer care in the United States. See Video Abstract at http://links.lww.com/DCR/B584.

PREDICTORES PARA UN MARGEN POSITIVO DE RESECCIN CIRCUNFERENCIAL EN EL CNCER DE RECTO UNA AUDITORA VIGENTE DE LA BASE DE DATOS NACIONAL DE CANCER

ANTECEDENTES:El margen positivo de resección circunferencial es un predictor de recurrencia local y peor sobrevida en el cáncer de recto. Los programas nacionales destinados a mejorar los resultados del cáncer de recto se crearon por primera vez en 2011 y continúan evolucionando. La repercusión del margen de resección circunferencial durante este período de tiempo no se ha evaluado completamente en los Estados Unidos.OBJETIVO:Determinar la incidencia y los predictores para un margen positivo de resección circunferencial posterior a la resección del cáncer de recto, según las características del paciente, el proveedor y el tumor.DISEÑO:Estudio de cohorte retrospectivo.AMBITO:Base de datos nacional de cáncer, 2011-2016.PACIENTES:Adultos que se sometieron a proctectomía por adenocarcinoma de recto con un estadío por patología I-III.PRINCIPALES VARIABLES EVALUADAS:Tasa y predictores para un margen positivo de resección circunferencial, definido como margen de resección ≤ 1 mm.RESULTADOS:De 52,620 casos, la condición del margen de resección circunferencial se informó en el 90% (n = 47,331) y positivo en el 18.4% (n = 8,719). El análisis no ajustado mostró que los pacientes con margen positivo de resección circunferencial se presentó con mayor frecuencia en hombres, tenían un seguro social y viajes más cortos, se operaron de proctectomía total abierta y robótica, y fueron tratados en las regiones del sur y el oeste en redes integradas de cáncer (todos p <0,001). El análisis multivariado destacó que el margen proximal y / o distal positivo de la pieza resecada tenía la asociación más fuerte con el margen postivo de resección circunferencial (OR 15,6; IC del 95%: 13,6-18,1, p <0,001). La invasión perineural, la proctectomía total, el abordaje robótico, la quimioradioterapia neoadyuvante, la red de cáncer integrada, el tamaño y grado del tumor avanzado y la raza afroamericana tenían un mayor riesgo de un margen de una resección positiva circunferencial (todos p <0,050). El abordaje laparoscópico, la cirugía en las regiones Norte, Sur y Medio Oeste, un mayor volumen hospitalario y distancia de viaje, estadio T más bajo y mayores ingresos se asociaron con una disminución del riesgo (todos p <0,028).LIMITACIONES:Estudio de cohorte retrospectivo con variables limitadas disponibles para análisis.CONCLUSIONES:A pesar del establecimiento de iniciativas nacionales, la tasa de margen positivo de resección circunferencial continúa siendo alarmante, 18,4%. El índice continuamente elevado junto a los predictores de un margen positivo de resección circunferencial hace un llamado para una mayor educación, evaluaciones específicas de mejora de la calidad y difusión de las auditorías para mejorar la atención del cáncer de recto en los Estados Unidos. Vea el resumen de video en http://links.lww.com/DCR/B584. Consulte Video Resumen en http://links.lww.com/DCR/B584.

Statistical, Clinical, Methodological Evaluation of Local Recurrence Following Transanal Total Mesorectal Excision for Rectal Cancer: A Systematic Review

BACKGROUND

A recent Norwegian moratorium challenged the status quo of transanal total mesorectal excision for rectal cancer by reporting increased early multifocal local recurrences.

OBJECTIVE

The aim of this systematic review and meta-analysis was to evaluate the local recurrence rates following transanal total mesorectal excision as well as to assess statistical, clinical, and methodological bias in reports published to date.

DATA SOURCES

The PubMed and MEDLINE (via Ovid) databases were systematically searched.

STUDY SELECTION

Descriptive or comparative studies reporting rates of local recurrence at a median follow-up of 6 months (or more) after transanal total mesorectal excision were included.

INTERVENTIONS

Patients underwent transanal total mesorectal excision.

MAIN OUTCOME MEASURES

Local recurrence was any recurrence located in the pelvic surgery site. The untransformed proportion method of 1-arm meta-analysis was utilized. Untransformed percent proportion with 95% confidence interval was reported. Ad hoc meta-regression with the Omnibus test was utilized to assess risk factors for local recurrence. Among-study heterogeneity was evaluated: statistically by I2 and τ2, clinically by summary tables, and methodologically by a 33-item questionnaire.

RESULTS

Twenty-nine studies totaling 2906 patients were included. The pooled rate of local recurrence was 3.4% (2.7%-4.0%) at an average of 20.1 months with low statistical heterogeneity (I2 = 0%). Meta-regression yielded no correlation between complete total mesorectal excision quality (p = 0.855), circumferential resection margin (p = 0.268), distal margin (p = 0.886), and local recurrence rates. Clinical heterogeneity was substantial. Methodological heterogeneity was linked to the excitement of novelty, loss aversion, reactivity to criticism, indication for transanal total mesorectal excision, nonprobability sampling, circular reasoning, misclassification, inadequate follow-up, reporting bias, conflict of interest, and self-licensing.

LIMITATIONS

The studies included had an observational design and limited sample and follow-up.

CONCLUSION

This systematic review found a pooled rate of local recurrence of 3.4% at 20 months. However, given the substantial clinical and methodological heterogeneity across the studies, the evidence for or against transanal total mesorectal excision is inconclusive at this time.

Robotic Transanal Total Mesorectal Excision (RTaTME): State of the Art

Total mesorectal excision (TME) is the gold standard technique for the surgical management of rectal cancer. The transanal approach to the mesorectum was introduced to overcome the technical difficulties related to the distal rectal dissection. Since its inception, interest in transanal mesorectal excision has grown exponentially and it appears that the benefits are maximal in patients with mid-low rectal cancer where anatomical and pathological features represent the greatest challenges. Current evidence demonstrates that this approach is safe and feasible, with oncological and functional outcome comparable to conventional approaches, but with specific complications related to the technique. Robotics might potentially simplify the technical steps of distal rectal dissection, with a shorter learning curve compared to the laparoscopic transanal approach, but with higher costs. The objective of this review is to critically analyze the available literature concerning robotic transanal TME in order to define its role in the management of rectal cancer and to depict future perspectives in this field of research.

SP rTaTME: initial clinical experience with single-port robotic transanal total mesorectal excision (SP rTaTME)

BACKGROUND

The technical difficulty and steep learning curve of transanal total mesorectal excision (taTME) has limited widespread adoption. The single-port (SP) daVinci robot is designed to facilitate single-incision and natural-orifice transluminal endoscopic surgery (NOTES). This paper describes the first clinical experience of single-port robotic taTME (SP rTaTME).

METHODS

This was a prospective study on consecutive patients with rectal cancer who underwent SP rTaTME proctosigmoidectomy with handsewn coloanal anastomosis in December 2018 and January 2019. The primary outcome was technical feasibility of the procedure. The secondary outcomes include blood loss, intraoperative complications, length of hospital stay, quality of the TME specimen, short- and long-term morbidity and mortality, as well as short-term oncologic follow -up.

RESULTS

There were two patients, a 48-year-old male and a 38-year-old female. Both operations were completed successfully without complications or conversion. Estimated blood loss was 200 mL and 130 mL. In both cases the TME was completed transanally using the SP robot. In the first patient, the abdominal portion was completed through an abdominal single-incision; in the second patient the operation was entirely performed transanally as a pure NOTES procedure. In both cases, the final pathology report showed a complete TME with negative margins. Patients were discharged on postoperative day 3 and 4,respectively. There was no long-term morbidity or mortality.

CONCLUSIONS

SP rTaTME is feasible and can be safely performed. It provides excellent optics and dexterity to work in a limited space. Future studies are required to further define the safety profile and the ultimate utility of the SP robot for taTME.

Survival following surgical treatment for anorectal melanoma seems similar for local excision and extensive resection regardless of nodal involvement

BACKGROUND

Anorectal melanoma is a rare malignancy with a dismal prognosis. The purpose of this study was to investigate whether the survival per stage is influenced by the surgical approaches (local excision or extensive resection), to assess prognostic factors of survival, and to answer the question whether the practiced surgical approaches changed over time.

METHODS

Dutch cancer registry organizations (IKNL and PALGA) were queried for all patients with a diagnosis of anorectal melanoma (1989-2019). Patients with disseminated disease at diagnosis were excluded. Survival outcomes were compared for the two surgical approaches stratified by stage (clinical node negative (cN0) and clinical node positive (cN+)) and date of diagnosis.

RESULTS

A total of 103 patients were included in this study. In both cN0 and cN+ patients the surgical strategy did not significantly influence survival (cN0: 21.7% 5-year survival, median 25 months for local excision versus 13.7% 5-year survival, median 17 months for extensive resection (p = 0.228), cN+: 11.1% 5-year survival for local excision, median 17 months versus 8.7% 5-year survival, median 14 months for extensive resection (p = 0.741)). Stage and date of diagnosis showed to be prognostic factors of survival. The ratio between the two surgical approaches was unchanged over three decades.

CONCLUSIONS

Extensive resection does not seem to improve survival in both cN0 and cN+ anorectal melanoma patients compared to local excision. However in the past three decades no shift towards local excision has been found. cN+ stage and an older date of diagnosis are predictors for worse survival.

Transanal total mesorectal excision outcomes for advanced rectal cancer in a complex surgical population

BACKGROUND

Total mesorectal excision (TME) is the gold standard for oncologic resection in low and mid rectal cancers. However, abdominal approaches to TME can be hampered by poor visibility, inadequate retraction, and distal margin delineation. Transanal TME (taTME) is a promising hybrid technique that was developed to mitigate the difficulties of operating in the low pelvis and to optimize the circumferential resection and distal margins.

METHODS

The objective of this study was to characterize our experience implementing taTME at our institution in a technically challenging patient population. We performed a retrospective review of consecutive patients who underwent taTMEs between November 2013 and May 2019 for rectal cancer at a tertiary community cancer center. Outcome measures included pathologic grading of TME specimen, post-operative complications, and oncologic outcomes.

RESULTS

Forty-four patients with mid and low rectal cancer underwent low anterior resection via taTME. The most common staging modality was rectal MRI which demonstrated T3 or T4 tumors in 89% of our patients prior to neoadjuvant. Eighty-six percent of patients underwent neoadjuvant chemoradiation. The initial cases were performed sequentially as a single team, but we later transitioned to a synchronous, two-team approach. Ninety-one percent of TME grades were complete or near complete. Only one patient (2.3%) had a positive circumferential margin. Six patients developed anastomotic leaks with an overall anastomotic complication rate of 18.2%. Two patients (4.5%) with primary rectal cancer developed local recurrence, one of which developed multifocal local recurrence.

CONCLUSIONS

Using the taTME approach on selected locally advanced low rectal cancers, especially in technically complex irradiated and obese male patients, has yielded comparably safe and effective outcomes to laparoscopic proctectomy.

Locoregional recurrences after transanal total mesorectal excision of rectal cancer during implementation

Background

Transanal total mesorectal excision (TaTME) has been proposed as an approach in patients with mid and low rectal cancer. The TaTME procedure has been introduced in the Netherlands in a structured training pathway, including proctoring. This study evaluated the local recurrence rate during the implementation phase of TaTME.

Methods

Oncological outcomes of the first ten TaTME procedures in each of 12 participating centres were collected as part of an external audit of procedure implementation. Data collected from a cohort of patients treated over a prolonged period in four centres were also collected to analyse learning curve effects. The primary outcome was the presence of locoregional recurrence.

Results

The implementation cohort of 120 patients had a median follow up of 21·9 months. Short‐term outcomes included a positive circumferential resection margin rate of 5·0 per cent and anastomotic leakage rate of 17 per cent. The overall local recurrence rate in the implementation cohort was 10·0 per cent (12 of 120), with a mean(s.d.) interval to recurrence of 15·2(7·0) months. Multifocal local recurrence was present in eight of 12 patients. In the prolonged cohort (266 patients), the overall recurrence rate was 5·6 per cent (4·0 per cent after excluding the first 10 procedures at each centre).

Conclusion

TaTME was associated with a multifocal local recurrence rate that may be related to suboptimal execution rather than the technique itself. Prolonged proctoring, optimization of the technique to avoid spillage, and quality control is recommended.