Robotic lateral pelvic lymph node dissection after chemoradiation for rectal cancer: a Western perspective

Short-term Outcomes of Robotic Lateral Pelvic Lymph Node Dissection for Lower Rectal Cancer

INTRODUCTION

Rectal cancer is among the main causes of cancer-related mortalities worldwide, necessitating more effective treatment strategies.　It is considered that lateral pelvic lymph node dissection (LPND) for rectal cancer patients can contribute to local tumor control and that robotic LPND (Rob-LPND) may be more suitable for LPND, due to technical advantages of precise manipulation in a narrow pelvic space.

METHODS

In this retrospective study, we evaluated the short-term outcomes of laparoscopic-LPND (Lap-LPND) versus Rob-LPND in patients undergoing radical surgery for rectal cancer.　Operative time, blood loss, urethral catheter reinsertion, duration of pelvic drainage tube placement, drainage volume, and postoperative hospital stay were compared between Lap-LPND and Rob-LPND.

RESULTS

Our findings revealed that Rob-LPND was associated with longer total operation time, but there was no significant difference in operation time between the two LPND techniques.　Urinary catheter re-insertion rates were lower in Rob-LPND; also, significant reductions in drainage tube duration, total drainage volume, and postoperative hospital stay were observed.

CONCLUSION

Rob-LPND may reduce postoperative total drainage volume and shorten postoperative hospital stays.　These improvement in short-term outcomes suggest potential clinical advantages of Rob-LPND.

Rise in Minimally Invasive Surgery for Colorectal Cancer Is Associated With Adoption of Robotic Surgery

BACKGROUND

Minimally invasive surgery is associated with improved short-term outcomes and similar long-term oncologic outcomes for patients with colorectal cancer compared with open surgery. Although the robotic approach has ergonomic and technical benefits, how it has impacted the utilization of traditional laparoscopic surgery and minimally invasive surgery overall is unclear.

OBJECTIVE

Describe trends in open, robotic, and laparoscopic approaches for colorectal cancer resections and examine factors associated with minimally invasive surgery.

DESIGN

Retrospective cohort study using data from the National Cancer Database from 2010 to 2020.

SETTING

Commission on Cancer-accredited US facilities.

PATIENTS

Patients diagnosed with nonmetastatic colon or rectal adenocarcinoma.

MAIN OUTCOME MEASURES

Surgical approach rates (open, robotic, and laparoscopic).

RESULTS

We identified 475,001 patients diagnosed with nonmetastatic colorectal adenocarcinoma, of whom 192,237 (40.5%) underwent open surgery, 64,945 (13.7%) underwent robotic surgery, and 217,819 (45.9%) underwent laparoscopic surgery. For colon cancer, laparoscopic minimally invasive surgery use steadily increased, with a peak prevalence of 54.0% in 2016, and total minimally invasive surgery (robotic + laparoscopic) was performed more often than open surgery from 2013 through 2020. For rectal cancer, laparoscopic minimally invasive surgery had a peak prevalence of 37.2% in 2014 and declined from 2014 through 2020; robotic surgery prevalence increased throughout the study period (5.5% in 2010, 24.7% in 2015, and 48.8% in 2020). Minimally invasive surgery use increased in facilities performing robotic surgery every year during the study period. For both colon and rectal cancer, the use of open surgery decreased across all facilities throughout the study period.

LIMITATIONS

This study used the National Cancer Database, which may not be generalizable to non-Commission on Cancer institutions.

CONCLUSIONS

Minimally invasive surgery steadily increased across all facilities from 2010 through 2020. Open resections declined, laparoscopic resections plateaued, and robotic resections increased for colon and rectal cancer. Minimally invasive surgery increases may be driven by increases in robot-assisted surgery. See Video Abstract.

EL AUMENTO DE LA CIRUGA MNIMAMENTE INVASIVA PARA EL CNCER COLORRECTAL SE ASOCIA CON LA ADOPCIN A LA CIRUGA ROBTICA

ANTECEDENTES:La cirugía mínimamente invasiva se asocia con mejores resultados a corto plazo y resultados oncológicos similares a largo plazo para pacientes con cáncer colorrectal en comparación con la cirugía abierta. Aunque el abordaje robótico tiene beneficios ergonómicos y técnicos, no está claro cómo ha afectado la utilización de la cirugía laparoscópica tradicional y la cirugía mínimamente invasiva en general.OBJETIVO:Describir las tendencias en los abordajes abiertos, robóticos y laparoscópicos para las resecciones de cáncer colorrectal y examinar los factores asociados con la cirugía mínimamente invasiva.DISEÑO:Estudio de cohorte retrospectivo utilizando datos de la Base de Datos Nacional del Cáncer desde 2010 hasta 2020.ESCENARIO:Centros estadounidenses acreditados por la Comisión sobre el Cáncer.PACIENTES:Pacientes diagnosticados con adenocarcinoma de colon o recto no metastásico.PRINCIPALES MEDIDAS DE VALORACIÓN:Tasas de abordaje quirúrgico (abierto, robótico, laparoscópico).RESULTADOS:Identificamos 475.001 pacientes con diagnóstico de adenocarcinoma colorrectal no metastásico, de los cuales 192.237 (40,5%) se sometieron a cirugía abierta, 64.945 (13,7%) se sometieron a cirugía robótica y 217.819 (45,9%) se sometieron a cirugía laparoscópica. Para el cáncer de colon, el uso de cirugía mínimamente invasiva laparoscópica aumentó de manera constante, con una prevalencia máxima del 54,0% en 2016, y la cirugía mínimamente invasiva total (robótica + laparoscópica) se realizó con mayor frecuencia que la cirugía abierta desde 2013 hasta 2020. Para el cáncer de recto, la cirugía mínimamente invasiva laparoscópica tuvo una prevalencia máxima del 37,2% en 2014 y disminuyó desde 2014 hasta 2020; La prevalencia de la cirugía robótica aumentó durante el período de estudio (5,5 % en 2010, 24,7 % en 2015, 48,8 % en 2020). El uso de cirugía mínimamente invasiva aumentó en los centros que realizan cirugía robótica cada año durante el período de estudio. Tanto para el cáncer de colon como para el cáncer de recto, el uso de cirugía abierta disminuyó en todos los centros durante el período de estudio.LIMITACIONES:Se utilizó la base de datos nacional sobre el cáncer, que puede no ser generalizable a instituciones que no pertenecen a la Comisión sobre el Cáncer.CONCLUSIONES:La cirugía mínimamente invasiva aumentó de manera constante en todos los centros entre 2010 y 2020. Las resecciones abiertas disminuyeron, las resecciones laparoscópicas se estabilizaron y las resecciones robóticas aumentaron para el cáncer de colon y recto. Los aumentos de la cirugía mínimamente invasiva pueden estar impulsados por aumentos en la cirugía asistida por robot. (Traducción--Ingrid Melo ).

Surgical navigation for targeted retroperitoneal lymph-node removal: a randomised, controlled, phase 3 trial

Background

Metastatic retroperitoneal lymph node dissection (LND) for nodal recurrence is applied for a variety of cancers, such as urological, gynaecological and rectal cancer. Precise localisation and resection of these lymph nodes (LNs) during surgery can be challenging, especially after previous radiotherapy or surgery. The objective of this study was to assess the added value of surgical navigation for targeted LND in the retroperitoneum.

Methods

We performed an open-label randomised, controlled, phase 3 trial at the Netherlands Cancer Institute, Amsterdam. Eligible participants were over 18 years of age, scheduled for targeted retroperitoneal LND by laparotomy, with removal of one or more suspected (targeted) LN(s) as assessed by diagnostic imaging. Patients were randomised (1:1) between conventional LND and LND using surgical navigation, by means of a minimisation method stratified for tumour origin (urological, colorectal and other). For the surgical navigation, a digital 3D model of the patients' anatomy was created from diagnostic CT scans, including delineation of the targeted LN(s). The 3D model was linked to the patients' position in the operation room. Using an electromagnetic tracking system, with a sterile tracked pointer, the actual position of the pointer was shown in the 3D model, enabling the surgeon to localize the targeted LN(s). The primary outcome of the study was the percentage of successful procedures. Success was defined as no residual target LN(s) visible on postoperative CT imaging. This study was registered with ClinicalTrials.gov, NCT05867095.

Findings

From January 2017 to December 2020, 69 participants were included in the study, 35 (51%) in the conventional arm and 34 (49%) in the navigation arm. Four patients were not evaluable and excluded from further analysis; three in the conventional arm (patients withdraw from study participation), one in the navigation arm (discontinued surgery, misclassified diagnosis). According to intention-to-treat analysis, 50% (16/32) of the surgical procedures was successful in the conventional arm, versus 85% (28/33) in the surgical navigation arm (one-tailed p = 0.0028, 90% CI: 14%-56%). Using the Clavien-Dindo classification, the overall complication rate was comparable between the conventional arm and the navigation arm. Surgeons judged the surgical navigation setup as valuable, the median preference score to use surgical navigation was 3.7 (3.3-4.0) (scale 1-5), and the median system usability score was 75 (70-85) (scale 0-100).

Interpretation

Surgical navigation allows for significantly better localisation and removal of target LN(s) in the retroperitoneum.

Funding

This research was supported by the KWF-Alpe d'HuZes (NKI 2014-6596) and by an institutional grant of The Dutch Cancer Society and of the Dutch Ministry of Health, Welfare and Sport.

The current multidisciplinary management of rectal cancer

Multidisciplinary management of rectal cancer has rapidly evolved over the last several years. This review describes recent data surrounding total neoadjuvant therapy, organ preservation, and management of lateral pelvic lymph nodes. It then presents our treatment algorithm for management of rectal cancer at The University of Texas MD Anderson Cancer Center in the context of this and other existing literature. As part of this discussion, the review describes how we tailor management based upon both patient and tumor-related factors in an effort to optimize patient outcomes.

Risk factors for lateral lymph node metastasis based on the molecular profiling of rectal cancer

AIM

The association between molecular profiles and lateral lymph node metastasis (LLNM) in patients with rectal cancer remains unclear. Therefore, this study aimed to identify the molecular profiles of rectal cancer associated with LLNM.

METHOD

We retrospectively examined patients who underwent rectal cancer surgery with lateral lymph node dissection without preoperative treatment and whose surgically resected specimens were evaluated using multiomics-based analyses from 2014 to 2019. We compared the clinical characteristics and molecular profiles of patients with pathological LLNM (pLLNM+) with those of patients without (pLLNM-) and identified risk factors for LLNM.

RESULTS

We evaluated a total of 123 patients: 18 with and 105 without pLLNM. The accumulation of mutations in genes key for the development of colorectal cancer were similar between the groups, as was the tumour mutation burden. The distribution of consensus molecular subtypes (CMS) was significantly different between the groups (p = 0.0497). The pLLNM+ patients had a higher prevalance of CMS4 than the pLLNM- patients (77.8% vs. 51.4%). According to the multivariate analysis, the independent risk factors for LLNM were a short-axis diameter of the lateral lymph node of ≥6.0 mm and CMS4; furthermore, the presence of either or both had a sensitivity of 100% for the diagnosis of LLNM.

CONCLUSION

Lateral lymph node size and CMS4 are useful predictors of LLNM. The combination of CMS classification and size criteria was remarkably sensitive for the diagnosis of LLNM.

Robot-assisted lateral pelvic lymph node dissection in patients with advanced rectal cancer: a single-center experience of 65 cases

The treatment of lateral pelvic lymph node (LPLN) metastasis of rectal cancer has evolved because of technical difficulties from open surgery to laparoscopy and, recently, robot-assisted surgery. This study aimed to evaluate the technical feasibility and short- and long-term outcomes of robot-assisted LPLN dissection (LPND) following total mesorectal excision (TME) in advanced rectal cancer. Clinical data of 65 patients who underwent robotic-assisted TME with LPND from April 2014 to July 2022 were reviewed. Data regarding operative details, postoperative morbidity (within 90 postoperative days) for short-term outcomes and lateral recurrence as long-term outcomes were analyzed. Among the 65 patients with LPND, preoperative chemoradiotherapy was performed in 49 (75.4%). The mean operative time was 306.8 (range 191-477) min, and the mean time of unilateral LPND was 38.6 (range 16-66) min. LPND was bilaterally performed in 19 (29.2%) patients. The mean number of each side of harvested LPLNs was 6.8. Lymph node metastasis was observed in 15 (23.0%) patients, and 10 (15.4%) patients had postoperative complications. Lymphocele (n = 3) and pelvic abscess (n = 3) were the most common, followed by voiding difficulty, erectile dysfunction, obturator neuropathy, and sciatic neuropathy (all n = 1). During the 25 months of median follow-up, no lateral recurrence of the LPND site was noted. Robot-assisted LPND following TME is safe and feasible and showed acceptable short- and long-term outcomes. Despite some study limitations, we may be able to apply this strategy more widely through subsequent prospective controlled studies.

Magnetic Resonance Imaging Directed Surgical Decision Making for Lateral Pelvic Lymph Node Dissection in Rectal Cancer After Total Neoadjuvant Therapy (TNT)

OBJECTIVE

Lateral pelvic lymph node (LPLN) metastases are an important cause of preventable local failure in rectal cancer. The aim of this study was to evaluate clinical and oncological outcomes following magnetic resonance imaging (MRI)-directed surgical selection for lateral pelvic lymph node dissection (LPLND) after total neoadjuvant therapy (TNT).

METHODS

A retrospective consecutive cohort analysis was performed of rectal cancer patients with enlarged LPLN on pretreatment MRI. Patients were categorized as LPLND or non-LPLND. The main outcomes were lateral local recurrence rate, perioperative and oncological outcomes and factors associated with decision making for LPLND.

RESULTS

A total of 158 patients with enlarged pretreatment LPLN and treated with TNT were identified. Median follow-up was 20 months (interquartile range 10-32). After multidisciplinary review, 88 patients (56.0%) underwent LPLND. Mean age was 53 (SD±12) years, and 54 (34.2%) were female. Total operative time (509 vs 429 minutes; P =0.003) was greater in the LPLND group, but median blood loss ( P =0.70) or rates of major morbidity (19.3% vs 17.0%) did not differ. LPLNs were pathologically positive in 34.1%. The 3-year lateral local recurrence rates (3.4% vs 4.6%; P =0.85) did not differ between groups. Patients with LPLNs demonstrating pretreatment heterogeneity and irregular margin (odds ratio, 3.82; 95% confidence interval: 1.65-8.82) or with short-axis ≥5 mm post-TNT (odds ratio 2.69; 95% confidence interval: 1.19-6.08) were more likely to undergo LPLND.

CONCLUSIONS

For rectal cancer patients with evidence of LPLN metastasis, the appropriate selection of patients for LPLND can be facilitated by a multidisciplinary MRI-directed approach with no significant difference in perioperative or oncologic outcomes.

Current status and role of robotic approach in patients with low-lying rectal cancer

Utilization of robotic surgical systems has increased over the years. Robotic surgery is presumed to have advantages of enhanced visualization, improved dexterity, and reduced tremor, which is purported to be more suitable for rectal cancer surgery in a confined space than laparoscopic or open surgery. However, evidence supporting improved clinical and oncologic outcomes after robotic surgery remains controversial and limited despite the widespread adoption of robotic surgical systems. To date, numerous observational studies and a few randomized controlled trials have failed to demonstrate that short-term, oncological, and functional outcomes after a robotic surgery are superior to those of laparoscopic surgery for low rectal cancer patients. The objective of this review is to summarize the current state of robotic surgery and its impact on low-lying rectal cancer.

The Effectiveness of Machine Learning in Predicting Lateral Lymph Node Metastasis From Lower Rectal Cancer: A Single Center Development and Validation Study

AIM

Accurate preoperative diagnosis of lateral lymph node metastasis (LLNM) from lower rectal cancer is important to identify patients who require lateral lymph node dissection (LLND). We aimed to create an effective prediction model for LLNM using machine learning by combining preoperative information.

METHODS

We retrospectively examined patients who underwent primary rectal cancer surgery with unilateral or bilateral LLND between April 2010 and March 2020 at a single institution. Using the machine learning software "Prediction One" (Sony Network Communications), we developed a prediction model in the training cohort that included 267 consecutive patients (500 sides) from April 2010. Clinicopathological data obtained from the preoperative examinations were used as the learning items. In the validation cohort that included subsequent patients until March 2020, we compared the discriminating powers of the prediction model and the conventional method using the short-axis diameter of the largest lateral lymph node, as detected on magnetic resonance imaging.

RESULTS

The area under the receiver operating characteristic curve (AUC) of the prediction model was 0.903 in the validation cohort comprising 56 patients (107 sides). This indicated significantly higher predictive power than that of the conventional method (AUC = 0.754; P = .022). Using the cutoff values defined in the training cohort, the accuracy, sensitivity, and specificity of the prediction model were 80.4%, 90.0%, and 79.4%, respectively. The model was able to correctly predict four of five sides comprising LLNM with the short-axis diameters ≤4 mm.

CONCLUSION

Machine learning contributed to the creation of an effective prediction model for LLNM.