S122: impact of fluorescence and 3D images to completeness of lateral pelvic node dissection

The role of lateral pelvic lymph node dissection in advanced rectal cancer: a review of current evidence and outcomes

Metastatic lateral pelvic lymph nodes (LPNs) in rectal cancer significantly impact the prognosis and treatment strategies. Western practices emphasize neoadjuvant chemoradiotherapy (CRT), whereas Eastern approaches often rely on LPN dissection (LPND). This review examines the evolving role of LPND in the context of modern treatments, including total neoadjuvant therapy (TNT), and the impact of CRT on the management of clinically suspicious LPNs. We comprehensively reviewed the key literature comparing the outcomes of LPND versus preoperative CRT for rectal cancer, focusing on recent advancements and ongoing debates. Key studies, including the JCOG0212 trial and recent multicenter trials, were analyzed to assess the efficacy of LPND, particularly in conjunction with preoperative CRT or TNT. Current evidence indicates that LPND can reduce local recurrence rates compared to total mesorectal excision alone in patients not receiving radiation therapy. However, the benefit of LPND in the context of neoadjuvant CRT is influenced by the size and pretreatment characteristics of LPNs. While CRT can effectively control smaller metastatic LPNs, larger or clinically suspicious LPNs may require LPND for optimal outcomes. Advances in surgical techniques, such as robotic-assisted LPND, offer potential benefits but also present challenges and complications. The role of TNT in controlling metastatic LPNs and improving patient outcomes is emerging but remains underexplored. The decision to perform LPND should be individualized based on patient-specific factors, including LPN size, response to neoadjuvant treatment, and surgeon expertise. Future research should focus on optimizing treatment protocols and further evaluating the role of TNT in managing metastatic LPNs.

Role of Lateral Pelvic Node Dissection in Rectal Cancer Surgery

The role of lateral pelvic lymph node dissection in the treatment of patients with locally advanced rectal cancer is a matter of controversy. Surgical practices in Korea and Japan have accepted this approach and are widely utilized; however, it is not routinely incorporated in the practice of countries in the Western hemisphere. This review will examine the role of lateral pelvic lymph node dissection.

The use of indocyanine green for lateral lymph node dissection in rectal cancer-preliminary data from an emerging procedure: a systematic review of the literature

INTRODUCTION

Lateral lymph node dissection (LLND) for rectal cancer is still not a widely established technique owing to the existing controversy between Eastern and Western countries and the lack of well-designed studies. The risk of complications and the paucity of long-term oncological results are significant drawbacks for further applying this technique. The use of indocyanine green (ICG) near-infrared (NIR) fluorescence for LLND appears as a promising technique for enhancing postoperative and oncological outcomes. This review aims to evaluate the emerging role of ICG during LLND and present the benefits of its application.

MATERIALS AND METHODS

Systematic electronic research was conducted in PubMed and Google Scholar using a combination of medical subject headings (MeSH). Studies presenting the use of ICG during LLND, especially in terms of harvested lymph nodes, were included and reviewed. Studies comparing LLND with ICG (LLND + ICG) or without ICG (LLND-alone) were further analyzed for the number of lymph nodes and postoperative outcomes.

RESULTS

In total, 13 studies were found eligible and analyzed for different parameters. LLND + ICG is associated with significantly increased number of harvested lateral lymph nodes (p < 0.05), minor blood loss, decreased operative time, and probably decreased urinary retention postoperatively compared with LLND-alone.

CONCLUSIONS

The use of ICG fluorescence during LLND is a safe and feasible technique for balancing postoperative outcomes and the number of harvested lymph nodes. Well-designed studies with long-term results are required to elucidate the oncological benefits and establish this promising technique.

Sequential Lateral Lymphatic Metastasis Shows Similar Oncologic Outcomes to Upward Spread in Advanced Rectal Cancer After Preoperative Chemoradiotherapy

BACKGROUND

Whether lateral pelvic node metastasis should be considered as a regional or systemic disease is a long-standing debate. Although previous Japanese studies have considered it to be locoregional disease, Western countries consider it a systemic disease and do not perform lateral pelvic node dissection after preoperative chemoradiotherapy.

OBJECTIVE

To evaluate whether lateral pelvic node metastasis is a systemic or regional disease that is amenable to curative resection.

DESIGN

Retrospective analysis of a prospectively collected database.

SETTING

This study was conducted at a tertiary cancer center.

PATIENTS

There were 616 consecutive patients who underwent curative total mesorectal excision alone or with lateral pelvic node dissection after preoperative chemoradiotherapy for locally advanced rectal cancer between 2011 and 2019.

MAIN OUTCOME MEASURES

Three-year disease-free and overall survival.

RESULTS

A total of 360 patients underwent total mesorectal excision, and 160 patients underwent total mesorectal excision with lateral pelvic node dissection. There was no difference in the 3-year disease-free survival (DFS; p = 0.844) or overall survival rates ( p = 0.921) between the groups. Patients with lateral pelvic node metastasis showed DFS similar to those with perirectal lymph node metastasis in the total mesorectal excision group. In a subgroup analysis, patients with internal iliac pelvic node metastasis showed a disease-free survival comparable to those with perirectal node involvement, and patients with other lateral pelvic node metastasis showed a DFS similar to those with intermediate node involvement. In the lateral pelvic node dissection group, the lateral pelvic node metastatic rate was 32.5%. On multivariate analysis, fewer than 8 of the unilateral harvested lateral pelvic nodes and advanced ypT stage were significantly associated with poor disease-free survival.

LIMITATION

The retrospective design.

CONCLUSIONS

Lateral lymphatic metastasis showed oncologic outcomes similar to those of upward spread, especially perirectal lymph nodes metastasis. Large cohort studies with long-term follow-up are required to confirm these results. See Video Abstract .

LAS METSTASIS LINFTICAS SECUENCIALES LATERALES MUESTRAN RESULTADOS ONCOLGICOS SIMILARES EN LA PROPAGACIN ASCENDENTE DEL CNCER RECTAL AVANZADO DESPUS DE LA RADIOQUIMIOTERAPIA PREOPERATORIA

ANTECEDENTES:Es un debate muy antiguo si las metástasis en los ganglios pélvicos laterales deben considerarse una enfermedad regional o sistémica. Si bien estudios japoneses anteriores las consideran como una enfermedad locorregional, en los países de occidente se las considera como una enfermedad sistémica por la cual no se realiza disección de ganglios pélvicos laterales después de una radioquimioterapia preoperatoria.OBJETIVOS:Evaluar si la metástasis en los ganglios pélvicos laterales se consideran como enfermedad sistémica o enfermedad regional susceptible de resección curativa.DISEÑO:Análisis retrospectivo de una base de datos recopilada prospectivamente.AJUSTE:Este estudio se realizó en un centro oncológico terciario.PACIENTES:616 pacientes consecutivos se sometieron a excisión total del mesorrecto curativa sola o con disección de los ganglios pélvicos laterales después de radioquimioterapia preoperatoria en casos de cáncer de recto localmente avanzado entre 2011 y 2019.PRINCIPALES MEDIDAS DE RESULTADO:Sobrevida global y libre de enfermedad a 3 años.RESULTADOS:Un total de 360 pacientes se sometieron a excisión total del mesorrecto y 160 pacientes se sometieron a excisión total del mesorrecto con disección de ganglios pélvicos laterales.No hubo diferencias en la sobrevida libre de enfermedad a 3 años (p = 0,844) ni en las tasas de sobrevida general (p = 0,921) entre los grupos. Los pacientes con metástasis en los ganglios pélvicos laterales mostraron una sobrevida libre de enfermedad similar a aquellos con metástasis en los ganglios linfáticos perirrectales que se encontraban en el grupo de excisión total del mesorrecto.En el análisis de subgrupos, los pacientes con metástasis en los ganglios pélvicos ilíacos internos mostraron una sobrevida libre de enfermedad comparable a aquellos con afección de los ganglios perirrectales y los pacientes con otras metástasis en los ganglios pélvicos laterales mostraron una sobrevida libre de enfermedad similar a aquellos con afección de los ganglios intermedios.En el grupo de disección de los ganglios pélvicos laterales, la tasa de metástasis en dichos ganglios fué del 32,5%. En el análisis multivariado, < de 8 ganglios pélvicos laterales resecados unilateralmente y el estadio ypT avanzado se asociaron significativamente con una menor sobrevida libre de enfermedad.LIMITACIÓN:El diseño retrospectivo del estudio.CONCLUSIONES:Las metástasis linfáticas laterales mostraron resultados oncológicos similares a la diseminación ascendente, especialmente las metástasis en los ganglios linfáticos perirrectales. Se requieren grandes estudios de cohortes con seguimiento a largo plazo para confirmar estos resultados. (Traducción-Dr. Xavier Delgadillo ).

Applications of Near-Infrared Fluorescence Imaging and Angiography of Inferior Vesical Artery in Laparoscopic Lateral Lymph Node Dissection: A Prospective Nonrandomized Controlled Study

BACKGROUND

Near-infrared imaging with indocyanine green has been used to guide lateral lymph node dissection, yet its efficacy and benefits need further investigation.

OBJECTIVE

To investigate the efficacy and feasibility of near-infrared fluorescence imaging and angiography of the inferior vesical artery in laparoscopic lateral lymph node dissection.

DESIGN

A prospective nonrandomized controlled study.

SETTINGS

Single-center study.

PATIENTS

Patients with lower rectal cancer who underwent total mesorectal excision plus lateral lymph node dissection.

MAIN OUTCOME MEASURES

A cohort of 108 patients was enrolled. After propensity score matching, 29 patients in the near-infrared group and 50 patients in the non-near-infrared group were matched. The total number of harvested lateral lymph nodes, positive lateral lymph nodes, inferior vesical artery preservation, and postoperative urinary function were compared.

RESULTS

After propensity score matching, both groups had similar baseline characteristics. The total number of harvested lateral lymph nodes in the near-infrared group was significantly higher (12 vs 9, p = 0.013), but positive lateral lymph nodes were similar between the 2 groups (1 vs 1, p = 0.439). The inferior vesical artery preservation ratio was significantly increased with the aid of indocyanine green angiography (93.1% vs 56.0%, p < 0.001). The non-near-infrared group required more days for urinary catheter removal than the near-infrared group (5 vs 4, p = 0.046). Urinary recatheterization tended to occur more frequently in the non-near-infrared group, with a marginally significant trend (16% vs 0%, p = 0.059). The non-near-infrared group tended to have more cases with residual urine volume ≥50 mL than the near-infrared group (20.0% vs 3.4%, p = 0.087), especially in the bilateral dissection subgroup (41.2% vs 0%, p = 0.041).

LIMITATIONS

Small sample size.

CONCLUSIONS

Near-infrared imaging increased the number of harvested lateral lymph nodes, whereas real-time indocyanine green fluorescence angiography ensured the preservation of the inferior vesical artery and tended to improve postoperative urinary function.

Fluorescence-guided colorectal surgery: applications, clinical results, and protocols

In recent years, the rise of minimally invasive surgery has driven the development of surgical devices. Indocyanine green (ICG) fluorescence imaging is receiving increased attention in colorectal surgery for improved intraoperative visualization and decision-making. ICG, approved by the U.S. Food and Drug Administration in 1959, rapidly binds to plasma proteins and is primarily intravascular. ICG absorption of near-infrared light (750-800 nm) and emission as fluorescence (830 nm) when bound to tissue proteins enhances deep tissue visualization. Applications include assessing anastomotic perfusion, identifying sentinel lymph nodes, and detecting colorectal cancer metastasis. However, standardized protocols and research on clinical outcomes remain limited. This study explores ICG's role, advantages, disadvantages, and potential clinical impact in colorectal surgery.

Long-term outcomes of indocyanine green fluorescence imaging-guided laparoscopic lateral pelvic lymph node dissection for clinical stage II/III middle-lower rectal cancer: a propensity score-matched cohort study

BACKGROUND

We previously reported that indocyanine green fluorescence imaging (ICG-FI)-guided laparoscopic lateral pelvic lymph node dissection (LPLND) was able to increase the total number of harvested lateral pelvic lymph nodes without impairing functional preservation. However, the long-term outcomes of ICG-FI-guided laparoscopic LPLND have not been evaluated. The aim of the present study was to compare the long-term outcomes of ICG-FI-guided laparoscopic LPLND to conventional laparoscopic LPLND without ICG-FI.

METHODS

This was a retrospective, multi-institutional study with propensity score matching. The study population included consecutive patients with middle-low rectal cancer (clinical stage II to III) who underwent laparoscopic LPLND between January 2013 and February 2018. The main evaluation items in this study were the 3-year overall survival, relapse-free survival (RFS), local recurrence rate, and lateral local recurrence (LLR) rate.

RESULTS

A total of 172 patients with middle-lower rectal cancer who had undergone laparoscopic LPLND were included in this study. After propensity score matching, 58 patients were matched in each of the ICG-FI and non-ICG-FI groups. There were no substantial differences in the baseline characteristics between the two groups. The ICG-FI group and non-ICG-FI group included 40 and 38 women and had a median age of 65 (IQR 60-72) and 66 (IQR 60-73) years, respectively. The median follow-up for all patients was 63.7 (IQR 51.3-76.8) months. The estimated respective 3-year overall survival, RFS, and local recurrence rates were 93.1%, 70.7%, and 5.2% in the ICG-FI group and 85.9%, 71.7%, and 12.8% in the non-ICG-FI group (p = 0.201, 0.653, 0.391). The 3-year cumulative LLR rate was 0% in the ICG-FI group and 9.3% in the non-ICG-FI group (p = 0.048).

CONCLUSIONS

This study revealed that laparoscopic LPLND combined with ICG-FI was able to decrease the LLR rate. It appears that ICG-FI could contribute to improving the quality of laparoscopic LPLND and strengthening local control of the lateral pelvis.

TRIALS REGISTRATION

This study was registered with the Japanese Clinical Trials Registry as UMIN000041372 ( http://www.umin.ac.jp/ctr/index.htm ).

Lateral pelvic sentinel lymph node biopsy using indocyanine green fluorescence navigation: can it be a powerful supplement tool for predicting the status of lateral pelvic lymph nodes in advanced lower rectal cancer

BACKGROUND

An innovative instrument for laparoscopy using indocyanine green (ICG) allows easy detection of sentinel lymph nodes (SLNs) in lateral pelvic lymph nodes (LPLNs). Here, we investigated the safety and efficacy of lateral pelvic SLN biopsy (SLNB) using ICG fluorescence navigation in advanced lower rectal cancer and evaluated the sensitivity and specificity of this technique to predict the status of LPLN.

METHODS

From April 1, 2017 to December 1, 2020, we conducted lateral pelvic SLNB using ICG fluorescence navigation during laparoscopic total mesorectal excision and lateral pelvic lymph node dissection (LLND) in 23 patients with advanced low rectal cancer who presented with LPLN but without LPLN enlargement. Data regarding clinical characteristics, surgical and pathological outcomes, lymph node findings, and postoperative complications were collected and analyzed.

RESULTS

We successfully performed the surgery using fluorescence navigation. One patient underwent bilateral LLND and 22 patients underwent unilateral LLND. The lateral pelvic SLN were clearly fluorescent before dissection in 21 patients. Lateral pelvic SLN metastasis was diagnosed in 3 patients and negative in 18 patients by frozen pathological examination. Among the 21 patients in whom lateral pelvic SLN was detected, the dissected lateral pelvic non-SLNs were all negative. All dissected LPLNs were negative in two patients without fluorescent lateral pelvic SLN.

CONCLUSION

This study indicated that lateral pelvic SLNB using ICG fluorescence navigation shows promise as a safe and feasible procedure for advanced lower rectal cancer with good accuracy, and no false-negative cases were found. No metastasis in SLNB seemed to reflect all negative LPLN metastases, and this technique can replace preventive LLND for advanced lower rectal cancer.

Indocyanine Green Fluorescence Guided Surgery in Colorectal Surgery

BACKGROUND

Indocyanine green (ICG) imaging has been increasingly used for intraoperative guidance in colorectal surgery over the past decade. The aim of this study was to review and organize, according to different type of use, all available literature on ICG guided colorectal surgery and highlight areas in need of further research and discuss future perspectives.

METHODS

PubMed, Scopus, and Google Scholar databases were searched systematically through November 2022 for all available studies on fluorescence-guided surgery in colorectal surgery.

RESULTS

Available studies described ICG use in colorectal surgery for perfusion assessment, ureteral and urethral assessment, lymphatic mapping, and hepatic and peritoneal metastases assessment. Although the level of evidence is low, results are promising, especially in the role of ICG in reducing anastomotic leaks.

CONCLUSIONS

ICG imaging is a safe and relatively cheap imaging modality in colorectal surgery, especially for perfusion assessment. Work is underway regarding its use in lymphatic mapping, ureter identification, and the assessment of intraperitoneal metastatic disease.

Short-term outcomes of near-infrared imaging using indocyanine green in laparoscopic lateral pelvic lymph node dissection for middle-lower rectal cancer: A propensity score-matched cohort analysis

Laparoscopic lateral pelvic lymph node dissection (LPND) is limited by complex neurovascular bundles in the narrow pelvic sidewall and various post-operative complications. Indocyanine green (ICG) has been applied to increase the number of harvested lymph nodes and reduce the injury of irrelevant vessels in patients with rectal cancer. However, few studies on the recurrence rate of ICG fluorescence imaging-guided laparoscopic LPND were reported. This retrospective study enrolled 50 middle- low rectal cancer patients who were treated by LPND. After propensity score matching, 20 patients were matched in each of the indocyanine green (ICG) guided imaging group (ICG group) and non-ICG guided imaging group (non-ICG group). The average follow-up time was 13.5 months (12-15 months). Our results showed that the total number of harvested lymph nodes in the ICG group was significantly higher than that in the non-ICG group (P < 0.05), and intraoperative blood loss and post-operative hospital stay times in the ICG group were less than those in the non-ICG group (P < 0.05). After 12 months of follow-up, no residual lymph node and local tumor recurrence were found for patients in the ICG group. Four patients in the non-ICG group detected residual lymph nodes at the 3-month visit. Our findings highlighted the importance of ICG fluorescence-guided imaging in LPND because it has unique advantages in improving the number of lymph node dissections, surgical accuracy, and decreasing the residual lymph nodes and local tumor recurrence. In addition, ICG fluorescence guidance technology can effectively shorten the operation time, and it is simple to operate, which is worth popularizing.

Near-Infrared Imaging Using Indocyanine Green for Laparoscopic Lateral Pelvic Lymph Node Dissection for Clinical Stage II/III Middle-Lower Rectal Cancer: A Propensity Score-Matched Cohort Study

BACKGROUND

The examination of the efficacy of near-infrared imaging using indocyanine green in laparoscopic lateral pelvic lymph node dissection remains insufficient.

OBJECTIVE

The aim of this study was to examine whether near-infrared imaging contributed to an increase in the total number of harvested lateral pelvic lymph nodes in laparoscopic lateral pelvic lymph node dissection.

DESIGN

This was a retrospective, multi-institutional study with propensity score matching.

SETTINGS

We conducted this study within the framework of the Yokohama Clinical Oncology Group in Japan.

PATIENTS

The study population included consecutive patients with middle-low rectal cancer (clinical stage II to III) who underwent laparoscopic lateral pelvic lymph node dissection between January 2013 and February 2018.

MAIN OUTCOME MEASURES

The total number of harvested lateral pelvic lymph nodes was compared in laparoscopic lateral pelvic lymph node dissection with and without near-infrared imaging.

RESULTS

A total of 172 eligible patients were included; 84 of these patients underwent laparoscopic surgery with near-infrared imaging. After propensity score matching, 58 patients were matched in each of the near-infrared and the non-near-infrared groups. The operation time in the near-infrared group was significantly longer than that in the non-near-infrared group (426 vs 369 min), and the amount of intraoperative blood loss in the near-infrared group was significantly smaller than that in the non-near-infrared group (13 vs 110 mL). The total number of harvested lateral pelvic lymph nodes in the near-infrared group was significantly higher than that in the non-near-infrared group (14 vs 9). There were no significant differences in the postoperative complication rates of the 2 groups.

LIMITATIONS

The limitations of the present study include its retrospective design.

CONCLUSIONS

This study revealed that laparoscopic lateral pelvic lymph node dissection combined with near-infrared imaging could increase the total number of harvested lateral pelvic lymph nodes without impairing functional preservation. See Video Abstract at http://links.lww.com/DCR/B800.This study was registered with the Japanese Clinical Trials Registry as UMIN000041372 (http://www.umin.ac.jp/ctr/index.htm).IMÁGENES CASI-INFRARROJAS UTILIZANDO VERDE DE INDOCIANINA EN LA DISECCIÓN LAPAROSCÓPICA DE GANGLIOS LINFÁTICOS PÉLVICOS LATERALES EN CASOS DE CÁNCER DE RECTO MEDIO-INFERIOR DE ESTADIO CLÍNICO II / III: ESTUDIO DE COHORTES CON PUNTUACIÓN DE PROPENSIÓNANTECEDENTES:El examen de la eficacia de las imágenes casi-infrarrojas utilizando le verde de indocianina en la disección laparoscópica de los ganglios linfáticos pélvicos laterales sigue siendo insuficiente.OBJETIVO:El objetivo de este estudio fue examinar si las imágenes casi-infrarrojas contribuyeron a un aumento en el número total de ganglios linfáticos pélvicos laterales recolectados durante su disección laparoscópica.DISEÑO:Estudio retrospectivo, multi-institucional con emparejamiento por puntuación de propensión.AJUSTES:Estudio realizado dentro el marco establecido por el Grupo de Oncología Clínica de Yokohama, Japón.PACIENTES:La población estudiada incluyó pacientes consecutivos con cáncer de recto medio-bajo (estadio clínico II a III) que se sometieron a una disección laparoscópica de los ganglios linfáticos pélvicos laterales entre enero de 2013 y febrero de 2018.PRINCIPALES RESULTADOS MEDIDAS:El número total de ganglios linfáticos pélvicos laterales extraídos se comparó en la disección laparoscópica de ganglios linfáticos pélvicos laterales con y sin imágenes casi-infrarrojas.RESULTADOS:Se incluyeron un total de 172 pacientes elegibles; 84 de estos pacientes se sometieron a cirugía laparoscópica con imágenes casi-infrarrojas. Después del emparejamiento por puntuación de propensión, 58 pacientes fueron emparejados en cada uno de los grupos de luz casi-infrarroja y los sin luz. El tiempo de operación en el grupo de luz casi-infrarroja fue significativamente más largo que en el grupo sin luz (426 frente a 369 min), y la cantidad de pérdida de sangre intraoperatoria en el grupo de luz casi-infrarroja fue significativamente menor que en el grupo sin luz (13 frente a 110 ml). El número total de ganglios linfáticos pélvicos laterales recolectados en el grupo de luz casi-infrarroja fue significativamente mayor que en el grupo sin luz (14 frente a 9). No hubo diferencias significativas en las tasas de complicaciones posoperatorias de los dos grupos.LIMITACIONES:Las limitaciones del presente estudio incluyen su diseño retrospectivo.CONCLUSIONES:Este estudio reveló que la disección laparoscópica de los ganglios linfáticos pélvicos laterales combinada con imágenes casi-infrarrojas podría aumentar el número total de ganglios linfáticos pélvicos laterales recolectados sin afectar la preservación funcional. Consulte Video Resumen en http://links.lww.com/DCR/B800. (Traducción-Dr. Xavier Delgadillo)Este estudio se registró en el Registro de Ensayos Clínicos de Japón como UMIN000041372 (http://www.umin.ac.jp/ctr/index.htm).

Minimally invasive surgery for colorectal cancer, a look back to look forward: a personal history

While laparoscopic colonoscopy was reported by several surgeons in the early 1990s, laparoscopic colorectal surgery has been attempted sporadically since 1992 in Korea. Then, in 2000, the Korean Laparoscopic Colorectal Surgery Study Group was established. Didactic lectures, videos, and live surgery by the early pioneers of this group inspired and helped many surgeons initiate the laparoscopic approach to the treatment of colorectal disease. As a result, the penetration rate of minimally invasive colorectal cancer surgery nationwide is increasing to 80% in 2018. As a witness on this journey, I would like to share my personal minimally invasive colorectal cancer surgery history and perspectives on future surgery in this field.

Learning curve analysis for lateral pelvic lymph node dissection in rectal cancers - Outcomes improve with experience

INTRODUCTION

Lateral pelvic lymph node dissection (LPLND) is a technically challenging procedure and its learning curve has not been analysed against an oncologically relevant outcome. The purpose of the study was to determine the learning curve for LPLND in rectal cancers using nodal retrieval as performance measure.

METHODS

Consecutive LPLND for rectal adenocarcinomas from a single institution were retrospectively analysed. Cumulative sum (CUSUM) control charts were used to detect difference in performance with respect to lymph node yield. Negative binomial regression was used to determine factors influencing nodal harvest using Incidence Risk Ratios (IRR). Separate CUSUM curves were generated for open and minimally invasive surgeries (MIS).

RESULTS

One-hundred and twenty patients were included and all received preoperative radiation. MIS was used in 53.3%. Median lymph node yield was 6 with 20% nodal positivity. Increasing experience (IRR - 1.196) and MIS (IRR - 1.586) were the only factors that influenced nodal harvest. CUSUM charts revealed that learning curve was achieved after the 83rd case overall and after the 19 operations in MIS. There was a 20% increase in nodal yield after every 30 MIS LPLND performed.

CONCLUSIONS

Learning curve for LPLND is relatively long and only increasing experience and minimally invasive operations increased nodal yield.

Colorectal cancer: Artificial intelligence and its role in surgical decision making

Despite several advances in the oncological management of colorectal cancer (CRC), there still remains a lacuna in the treatment strategy, which differs from center to center and on the philosophy of the treating clinician that is not without bias. Personalized treatment is essential for the treatment of CRC to achieve better long-term outcomes and to reduce morbidity. Surgery has an important role to play in the treatment. Surgical treatment of CRC is decided based on clinical parameters and investigations and hence likely to have judgmental errors. Artificial intelligence has been reported to be useful in the surveillance, diagnosis, treatment, and follow-up with accuracy in several malignancies. However, it is still evolving and yet to be established in surgical decision making in CRC. It is not only useful preoperatively but also intraoperatively. Artificial intelligence helps to rectify the human surgical decision when clinical data and radiological and laboratory parameters are fed into the computer and may guide correct surgical treatment.

Stepwise Improvement of Surgical Quality in Robotic Lateral Pelvic Node Dissection: Lessons From 100 Consecutive Patients With Locally Advanced Rectal Cancer

BACKGROUND

Lateral pelvic node dissection has significant technical difficulty and a high incidence of surgical morbidity. A steep learning curve is anticipated in performing lateral pelvic node dissection. However, no study has previously analyzed the learning curve and surgical skill acquisition for this complex procedure.

OBJECTIVES

We aimed to evaluate the learning process for performing robotic total mesorectal excision with lateral pelvic node dissection in patients with rectal cancer.

DESIGN

This is a retrospective analysis of a prospectively collected database.

SETTING

This study was conducted at a tertiary cancer center.

PATIENTS

A total of 100 patients who underwent robotic total mesorectal excision with lateral pelvic node dissection between 2011 and 2017 were included.

MAIN OUTCOME MEASURES

A cumulative sum analysis was calculated based on the number of unilateral retrieved lateral pelvic nodes. Operative time, estimated bloodloss, lateral pelvic node metastatic rate, postoperative morbidities, and local recurrence were also analyzed.

RESULTS

Cumulative sum modeling suggested 4 learning phases: learning I (33 patients), learning II (19 patients), consolidation (30 patients), and competence (18 patients). In the consolidation and competence phases, we adopted fluorescence imaging and standardized the surgical procedure on the basis of anatomical planes. The competence phase had the greatest number of unilateral retrieved lateral pelvic nodes (12.8 vs 4.9, 8.2, and 10.4; p < 0.001). Urinary complications, including urinary retention and postoperative α-blocker usage, were more frequently observed in learning phase I than in the competence phase (39.4% vs 16.7%, p = 0.034). During the median follow-up of 44.2 months, local recurrence in the pelvic sidewall was observed in 4 patients from learning phase I and in 1 patient from learning phase II.

LIMITATIONS

This study was limited by its retrospective design.

CONCLUSION

Completeness of the lateral pelvic node dissection procedure increased with the surgeon's experience and as new imaging systems and surgical technique standardization were implemented. Further studies are warranted to determine the oncologic outcomes associated with each phase. See Video Abstract at http://links.lww.com/DCR/B774.

MEJORA GRADUAL DE LA CALIDAD QUIRRGICA EN LA DISECCIN LINFTICA PLVICA LATERAL ROBTICA LECCIONES DE PACIENTES CONSECUTIVOS CON CNCER DE RECTO LOCALMENTE AVANZADO

ANTECEDENTES:La disección linfática pélvica lateral tiene una dificultad técnica significativa y una alta incidencia de morbilidad quirúrgica. Se prevé una curva de aprendizaje muy pronunciada al realizar la disección linfática pélvica lateral. Sin embargo, ningún estudio ha analizado previamente la curva de aprendizaje y la adquisición de habilidades quirúrgicas para este procedimiento.OBJETIVOS:Nuestro objetivo fue evaluar el proceso de aprendizaje para realizar la escisión total de mesorrecto robótica con disección linfática pélvica lateral en pacientes con cáncer de recto.DISEÑO:Este es un análisis retrospectivo de una base de datos recopilada prospectivamente.AJUSTE:Este estudio se realizó en un centro oncológico terciario.PACIENTES:Un total de 100 pacientes fueron sometidos a escisión total de mesorrecto robótica con disección linfática pélvica lateral entre 2011 y 2017.PRINCIPALES MEDIDAS DE DESENLACE:Se calculó un análisis de suma acumulativa basado en el número unilateral de ganglios pélvicos laterales recuperados. También se analizaron el tiempo operatorio, la pérdida de sangre estimada, la tasa de metástasis ganglionares pélvicas laterales, las morbilidades postoperatorias y la recidiva local.RESULTADOS:El modelado total acumulativo sugirió cuatro fases de aprendizaje: aprendizaje I (33 pacientes), aprendizaje II (19 pacientes), consolidación (30 pacientes) y competencia (18 pacientes). En las fases de consolidación y competencia, adoptamos imágenes de fluorescencia y estandarizamos el procedimiento quirúrgico basado en planos anatómicos, respectivamente. La fase de competencia tuvo el mayor número de ganglios pélvicos laterales recuperados unilateralmente (12,8 frente a 4,9, 8,2 y 10,4; p < 0,001). Las complicaciones urinarias, incluida la retención urinaria y el uso posoperatorio de bloqueadores beta, se observaron con más frecuencia en la fase de aprendizaje I que en la fase de competencia (39,4% frente a 16,7%, p = 0,034). Durante la mediana de seguimiento de 44,2 meses, se observó una recidiva local en la pared lateral pélvica en cuatro pacientes de la fase de aprendizaje I y en un paciente de la fase de aprendizaje II.LIMITACIONES:Este estudio estuvo limitado por su diseño retrospectivo.CONCLUSIÓNES:La completitud del procedimiento de disección linfática pélvica lateral aumentó con la experiencia del cirujano y a medida que se implementaron nuevos sistemas de imágenes y estandarización de técnicas quirúrgicas. Se necesitan más estudios para determinar los resultados oncológicos asociados con cada fase. Consulte Video Resumen en http://links.lww.com/DCR/B774.

Fluorescence Imaging in Colorectal Surgery: An Updated Review and Future Trends

Fluorescence imaging in colorectal surgery is considered a novel predominantly intraoperative method of ensuring a greater surgical success. The use of fluorescence is linked to advanced tumor visualization and projection of its lymphatics, both vessels and nodes, which results in a higher chance of achieving a total excision. Additionally, iatrogenic complications prove to be reduced using fluorescence during the surgical excision. The combination of fluorescence and artificial intelligence to better facilitate oncological surgery will soon become an established approach in operating rooms worldwide.

Current and future role of three-dimensional modelling technology in rectal cancer surgery: A systematic review

BACKGROUND

Three-dimensional (3D) modelling technology translates the patient-specific anatomical information derived from two-dimensional radiological images into virtual or physical 3D models, which more closely resemble the complex environment encountered during surgery. It has been successfully applied to surgical planning and navigation, as well as surgical training and patient education in several surgical specialties, but its uptake lags behind in colorectal surgery. Rectal cancer surgery poses specific challenges due to the complex anatomy of the pelvis, which is difficult to comprehend and visualise.

AIM

To review the current and emerging applications of the 3D models, both virtual and physical, in rectal cancer surgery.

METHODS

Medline/PubMed, Embase and Scopus databases were searched using the keywords “rectal surgery”, “colorectal surgery”, “three-dimensional”, “3D”, “modelling”, “3D printing”, “surgical planning”, “surgical navigation”, “surgical education”, “patient education” to identify the eligible full-text studies published in English between 2001 and 2020. Reference list from each article was manually reviewed to identify additional relevant papers. The conference abstracts, animal and cadaveric studies and studies describing 3D pelvimetry or radiotherapy planning were excluded. Data were extracted from the retrieved manuscripts and summarised in a descriptive way. The manuscript was prepared and revised in accordance with PRISMA 2009 checklist.

RESULTS

Sixteen studies, including 9 feasibility studies, were included in the systematic review. The studies were classified into four categories: feasibility of the use of 3D modelling technology in rectal cancer surgery, preoperative planning and intraoperative navigation, surgical education and surgical device design. Thirteen studies used virtual models, one 3D printed model and 2 both types of models. The construction of virtual and physical models depicting the normal pelvic anatomy and rectal cancer, was shown to be feasible. Within the clinical context, 3D models were used to identify vascular anomalies, for surgical planning and navigation in lateral pelvic wall lymph node dissection and in management of recurrent rectal cancer. Both physical and virtual 3D models were found to be valuable in surgical education, with a preference for 3D printed models. The main limitations of the current technology identified in the studies were related to the restrictions of the segmentation process and the lack of 3D printing materials that could mimic the soft and deformable tissues.

CONCLUSION

3D modelling technology has potential to be utilised in multiple aspects of rectal cancer surgery, however, it is still at the experimental stage of application in this setting.

Fluorescence vessel and ureter navigation during laparoscopic lateral lymph node dissection

BACKGROUND

Lateral lymph node metastasis in lower rectal cancer is considered a local disease in Japan, and guidelines suggest lateral lymph node dissection (LLND). However, laparoscopic procedures are relatively difficult. The ureter and hypogastric fascia must be dissected from the vesicohypogastric fascia to preserve the autonomic nerve and ureter. Additionally, lymph node dissection around the internal iliac artery is complex because many patterns of branching from the internal iliac artery exist. We investigated the utility of fluorescence ureter and vessel navigation using a near-infrared ray fluorescent ureteral catheter (NIRFUC) and indocyanine green (ICG).

METHODS

Fourteen patients who underwent laparoscopic LLND using fluorescence navigation were included. Eleven patients had rectal cancer, 1 had anal cancer, and 2 exhibited recurrence of rectal cancer. Eleven patients underwent NIRFUC insertion before surgery. Fluorescence vessel navigation (FVN) was performed with intraoperative ICG injections in 14 patients, with a total of 18 sides. The outcome measures were ureter navigation visibility, detection of the branch form from the internal iliac artery with FVN, differences between the fluorescence findings and anatomy of the internal iliac artery determined after LLND, and the surgical outcome.

RESULTS

In all 11 patients, the ureters were clearly identified as fluorescent before dissection around the ureter. FVN revealed the internal iliac, umbilical, and superior vesical arteries in all patients. The branch from the internal iliac artery according to the Adachi classification was revealed on 16 sides (89%). The time from intravenous ICG injection to fluorescence of the internal iliac artery was 38 (17-57) s. The time from intravenous injection to when the vessels were observed as fluorescent was 113 (65-661) s. No ureteral or vessel injuries occurred.

CONCLUSIONS

Fluorescence navigation of vessels and the ureter is feasible in laparoscopic LLND and has the potential to increase safety.

CLINICAL TRIAL REGISTRATION

Examination of fluorescence navigation for laparoscopic colorectal cancer surgery Research Ethics Committee of the Kawaguchi Municipal Medical Center (Saitama, Japan) approval number: 2020-3. https://kawaguchi-mmc.org/wp-content/uploads/clinicalresearch-r02.pdf.

Evaluation of bone erosion in rheumatoid arthritis patients by high-resolution peripheral quantitative computed tomography scans: Comparison between two semi-automated programs in a three-dimensional setting

AIM

The aim of this study was to compare OsiriX software with the previous published Medical Image Analysis Framework (MIAF) method to assess the volume of erosion in patients with rheumatoid arthritis (RA).

METHODS

Forty RA patients underwent high-resolution peripheral quantitative computed tomography scans of the second and third metacarpophalangeal joints, and thirty-four patients with any bone erosion were enrolled. Two techniques were applied to erosion evaluation: (a) semi-automated MIAF software, and (b) semi-automated segmentation by free open-source Digital Imaging and Communications in Medicine viewer, OsiriX software. MIAF has been published before, but this is the first time that OsiriX has been used in this way in rheumatology. Bland & Altman plots described agreement between methods.

RESULTS

Forty-eight erosions from 34 patients were analyzed. Mean age was 40.74 ± 5.32 years and mean disease duration was 10.68 ± 4.96 years. Both methods demonstrated a strong correlation regarding erosion volume (r = 0.96, P < 0.001). Median (interquartile range) of erosion volume was 12.14 (4.5-36.07) when MIAF was considered, and 11.80 (3.45-29.42) when the OsiriX tool was used (P = 0.139). MIAF and OsiriX showed good agreement when the Bland & Altman plot was performed. Evaluation by MIAF took 22.69 ± 6.71 minutes, whereas OsiriX took only 2.62 ± 1.09 minutes (P < 0.001).

CONCLUSION

The three-dimensional segmentation of bone erosions can be done by both MIAF and OsiriX software with good agreement. However, because OsiriX is a widespread tool and faster, its method seems to be more feasible for evaluating peripheral bone damage, especially bone erosions.

Optimizing outcomes of colorectal cancer surgery with robotic platforms

Advanced robotic technology makes it easier to perform total mesorectal excision procedures in the narrow pelvis for rectal cancer while maintaining the advantages of minimally invasive surgery. Robotic surgery for rectal cancer leads to lower conversion rates and faster recovery of urogenital function than conventional laparoscopic surgery. However, longer operative time and high cost are major weaknesses of robotic surgery. To date, most other short-term surgical outcomes, pathologic outcomes, and long-term oncologic outcomes of robotic surgery have not shown significant advantages over laparoscopic surgery. However, robotic surgery is still a valid and highly anticipated surgical approach for rectal cancer because it greatly reduces the surgeon's workload and learning curve. There are also advantages when robotic techniques are applied to technically demanding procedures such as lateral pelvic lymph node dissection or intersphincteric resection. The introduction of new surgical robot systems, including the da Vinci® SP system, is expected to expand the applications of robotic surgery and provide new advantages.

[Evidence of indocyanine green fluorescence in robotically assisted colorectal surgery : What is the status?]

BACKGROUND

Indocyanine green (ICG) fluorescence imaging is increasingly being used in various areas of abdominal surgery. The constant improvement in the technology enables easy intraoperative use and progressively influences operative decision-making, also in robotically assisted colorectal surgery.

OBJECTIVE

Summation of current evidence on the use of ICG fluorescence imaging in robotically assisted colorectal surgery.

MATERIAL AND METHODS

The assessment of evidence is based on a comprehensive literature search (PubMed).

RESULTS

First individual studies (feasibility, case matched, prospective cohort, multicenter phase II, single center randomized controlled study/trial) showed a significant reduction in the incidence of anastomotic leakage (AL) after colorectal anastomosis through the use of ICG fluorescence angiography (FA, 9.1% vs. 16.3%; p = 0.04). First feasibility studies demonstrated lymph node detection or navigation as well as ureter visualization.

CONCLUSION

The ICG-FA reliably detects tissue perfusion, quickly and effectively with few side effects. It can influence intraoperative decision-making and reduce AL rates. In addition, patients may be offered more precise tumor therapy via ICG sentinel lymph node (SLN) detection and lateral pelvic lymph node (LPN) mapping and navigation. Iatrogenic lesions, such as ureteral injuries can be sufficiently prevented by appropriate visualization; however, valid data in order to be able to derive standardized operative consequences require further convincing multicenter, randomized controlled trials (mRCT).

Robotic Surgery for Rectal Cancer: Operative Technique and Review of the Literature

The number of patients undergoing robotic surgery for rectal cancer has rapidly increased in Japan, since the government approved the procedure for national insurance coverage in April 2018. Robotic surgery has the potential to overcome some limitations of laparoscopic surgery, especially in the narrow pelvis, providing a three-dimensional view, articulated instruments, and a stable camera platform. Although meta-analyses and randomized controlled trials have failed to demonstrate the superiority of robotic surgery over laparoscopic surgery with respect to the short-term clinical outcomes, the published findings suggest that robotic surgery may be potentially beneficial for patients who are obese, male, or patients undergoing sphincter-preserving surgery for rectal cancer. The safety and feasibility of robotic surgery for lateral lymph node dissection, the standard procedure for locally advanced lower rectal cancer in Japan, have been demonstrated in some retrospective studies. However, additional prospective, randomized trials are required to determine the actual benefits of robotic surgery to ameliorate the urogenital and oncological outcomes. The cost of this approach is a long-standing principal concern. A literature search showed that the cost of robotic surgery for rectal cancer was 1.3-2.5 times higher per patient than that for the laparoscopic approach. We herein describe our surgical technique using a da Vinci Surgical System (S/Si/Xi) with 10 years of experience in performing robotic surgery. We also review current evidence regarding short-term clinical and long-term oncological outcomes, lateral lymph node dissection, and the cost of the procedure.