Short-term outcomes of complete mesocolic excision versus D2 dissection in patients undergoing laparoscopic colectomy for right colon cancer (RELARC): a randomised, controlled, phase 3, superiority trial

Nanomolecular machines: Pioneering precision medicine for neoplastic diseases through advanced diagnosis and treatment

Tumors pose a major threat to human health, accounting for nearly one-sixth of global deaths annually. The primary treatments include surgery, radiotherapy, chemotherapy, and immunotherapy, each associated with significant side effects. This has driven the search for new therapies with fewer side effects and greater specificity. Nanotechnology has emerged as a promising field in this regard, particularly nanomolecular machines at the nanoscale. Nanomolecular machines are typically constructed from biological macromolecules like proteins, DNA, and RNA. These machines can be programmed to perform specialized tasks with precise instructions. Recent research highlights their potential in tumor diagnostics-identifying susceptibility genes, detecting viruses, and pinpointing tumor markers. Nanomolecular machines also offer advancements in tumor therapy. They can reduce traditional treatment side effects by delivering chemotherapy drugs and enhancing immunotherapy, and they support innovative treatments like sonodynamic and phototherapy. Additionally, they can starve tumors by blocking blood vessels, and eliminate tumors by disrupting cell membranes or lysosomes. This review categorizes and explains the latest achievements in molecular machine research, explores their models, and practical clinical uses in tumor diagnosis and treatment. It aims to broaden the research perspective and accelerate the clinical adoption of these technologies.

Comparison of conventional resection to D3 lymphadenectomy in right-sided colon cancer: A retrospective cohort study

BACKGROUND

Lymphadenectomy during right hemicolectomy for colon cancer varies between the U.S. and Japan.

METHODS

Patients undergoing right hemicolectomy for non-metastatic right-sided colon cancer between 2010 and 2019 ​at U.S. and Japanese institutions were compared. Outcomes included survival, pathologic findings, and postoperative complications.

RESULTS

319 American patients (57 ​% female, mean age 70 years) underwent conventional resection and 308 Japanese patients (52 ​% female, mean age 70 years) underwent extended dissection. The conventional group underwent more laparotomies (26.6 ​% vs. 8.4 ​%, p ​< ​0.001), had more poorly differentiated histology (31.7 ​% vs. 11.0 ​%, p ​< ​0.01), lower lymph node yield (M ​= ​27 ​± ​11 vs. M ​= ​32 ​± ​14, p ​< ​0.001), and more 30-day readmissions (31 vs. 5, p ​< ​0.001). Adjusting for demographics, pathology, perioperative outcomes, and adjuvant chemotherapy, extended lymphadenectomy improved disease-free survival (HR 0.50; 95 ​% CI, 0.31-0.80; p ​= ​0.004), but not overall survival (HR 0.98; 95 ​% CI, 0.95-1.02; p ​= ​0.14).

CONCLUSIONS

Extended lymphadenectomy for right sided-colon cancer improves disease-free, but not overall, survival among Japanese patients.

Oncologic safety of transverse colon cancer surgery without central vessel ligation of middle colic artery

BACKGROUND

Surgical standardization for transverse colon cancers (TCC) has not been established, and the oncologic benefit of central vessel ligation (CVL) are still unclear. This study aimed to evaluate the oncologic safety of TCC surgery without CVL of the middle colic artery (MCA).

METHODS

This is a single-center, retrospective, observational, comparative study. The clinical, surgical, and pathological characteristics of the patients who underwent radical surgery for non-metastatic TCC between January 2012 and December 2020 were investigated, and the characteristic and oncologic outcomes of No CVL and CVL groups were compared.

RESULTS

The number of No CVL and CVL groups was 47 (44.3%) and 59 (55.7%), respectively. There was no statistically significant difference between the two groups in surgical complications, stage, mean number of retrieved lymph nodes (LN) (24.12 vs. 22.36 p = 0.464), mean number of metastatic LN (1.53 vs. 0.74, p = 0.163), mean proximal margin (19.2 cm vs. 16.7 cm, p = 0.139), mean distal margin (9.6 cm vs. 9.9 cm, p = 0.753), adjuvant chemotherapy, total recurrence rate (6.4 vs. 11.9%, p = 0.507), lymphatic recurrence rate (0.0% vs. 5.1%, p = 0.253), and local recurrence rate (2.1 vs. 1.7%, p = 0.984). Furthermore, there was no statistically significant difference of 5-year disease-free survival (DFS) and overall survival (OS) in stage II (DFS: 94.4 vs. 91.3%, p = 0.685, OS: 94.1 vs. 95.5%, p = 0.838) and stage III (DFS: 88.5 vs. 68.4%, p = 0.253, OS: 100.0% vs. 79.7, p = 0.328).

CONCLUSION

TCC surgery without CVL of the MCA showed comparable surgical and oncologic outcomes compared to surgery with CVL. Therefore, preservation of a branch of the MCA may be considered a safe option, when combined with adequate lymph node dissection, if necessary. A large, prospective, and controlled study will be necessary to provide solid evidence of the oncologic safety of this procedure.

Complete mesocolic excision (CME) impacts survival only for Stage III right-sided colon cancer: a systematic review and meta-analysis

INTRODUCTION

Complete mesocolic excision (CME) is widely adopted for its assumed superior oncological outcome. However, it's unclear if all right-sided colon cancer patients benefit from CME. The aim of this systematic review is to investigate whether CME contributes to postoperative outcomes and to determine the surgical indications for CME.

MATERIAL AND METHODS

We searched eligible articles about CME versus non-CME procedures for right-sided colon cancer in the OVID Medline, Embase, and Cochrane CENTRAL databases, and a meta-analysis was conducted.

RESULTS

Twenty-two articles and seven abstracts involving 8088 patients were included in this study. Among them, 3803 underwent CME and 4285 non-CME procedures. The analysis showed that CME was favoured for three-year disease-free survival (DFS) and overall survival (OS), for local, systemic, and total recurrence, and for hospital stay durations. However, increased vascular injury and longer surgery time were observed in CME. Regarding the three-year OS, the superiority of CME was observed only in Stage III. Additionally, no significant differences were observed between CME and non-CME groups regarding overall complications, 30-day readmission rates, reoperation, or postoperative mortality rates.

CONCLUSIONS

CME for right-sided colon cancer should be considered, particularly in Stage III patients, to contribute to improved oncological outcomes. However, careful attention must be paid to the increased risk of vascular injury.

Risk Factors for Postoperative Complications of Laparoscopic Right Colectomy: A Post Hoc Analysis of the RELARC Trial

BACKGROUND

There is concern regarding the possibility of postoperative complications for laparoscopic right colectomy.

OBJECTIVE

To evaluate the risk factors for postoperative complications for patients undergoing laparoscopic right colectomy.

DESIGN

This was an observational study.

SETTINGS

This was a post hoc analysis of a prospective, multicenter, randomized controlled trial (RELARC trial, NCT02619942).

PATIENTS

Patients included in the modified intention-to-treat analysis in the RELARC trial were all enrolled in this study.

MAIN OUTCOME MEASURES

Risk factors for postoperative complications were identified using univariate and multivariable logistic regression analysis.

RESULTS

Of 995 patients, 206 (20.7%) had postoperative complications. Comorbidity ( p = 0.02; OR: 1.544; 95% CI, 1.077-2.212) and operative time >180 minutes ( p = 0.03; OR: 1.453; 95% CI, 1.032-2.044) were independent risk factors for postoperative complications, whereas female sex ( p = 0.04; OR: 0.704; 95% CI, 0.506-0.980) and extracorporeal anastomosis ( p < 0.001; OR: 0.251; 95% CI, 0.166-0.378) were protective factors. Eighty patients (8.0%) had overall surgical site infection, 53 (5.3%) had incisional surgical site infection, and 33 (3.3%) had organ/space surgical site infection. Side-to-side anastomosis was a risk factor for overall surgical site infection ( p < 0.001; OR: 1.912; 95% CI, 1.118-3.268) and organ/space surgical site infection ( p = 0.005; OR: 3.579; 95% CI, 1.455-8.805). The extracorporeal anastomosis was associated with a reduced risk of overall surgical site infection ( p < 0.001; OR: 0.239; 95% CI, 0.138-0.413), organ/space surgical site infection ( p = 0.002; OR: 0.296; 95% CI, 0.136-0.646), and incisional surgical site infection ( p < 0.001; OR: 0.179; 95% CI, 0.099-0.322). Diabetes ( p = 0.039; OR: 2.090; 95% CI, 1.039-4.205) and conversion to open surgery ( p = 0.013; OR: 5.403; 95% CI, 1.437-20.319) were risk factors for incisional surgical site infection.

LIMITATIONS

Due to the retrospective nature, the key limitation is the lack of prospective documentation and standardization regarding the perioperative management of these patients, such as preoperative optimization, bowel preparation regimens, and antibiotic regimens, which may be confounder factors of complications. All surgeries were performed by experienced surgeons, and the patients enrolled were relatively young, generally healthy, and without obesity. It is unclear whether the results will be generalizable to obese and other populations worldwide.

CONCLUSIONS

Male sex, comorbidity, prolonged operative time, and intracorporeal anastomosis were independent risk factors for postoperative complications of laparoscopic right colectomy. Side-to-side anastomosis was associated with an increased risk of organ/space surgical site infection. Extracorporeal anastomosis could reduce the incidence of overall surgical site infection. Diabetes and conversion to open surgery were associated with an increased risk of incisional surgical site infection. See Video Abstract .

CLINICALTRIALSGOV IDENTIFIER

NCT02619942.

FACTORES DE RIESGO DE COMPLICACIONES POSOPERATORIAS EN COLECTOMA DERECHA LAPAROSCPICA UN ANLISIS POST HOC DEL ENSAYO RELARC

ANTECEDENTES:Existe preocupación con respecto a la posibilidad de complicaciones postoperatorias en colectomía derecha laparoscópica.OBJETIVO:Evaluar los factores de riesgo de complicaciones postoperatorias en pacientes sometidos a colectomía derecha laparoscópica.DISEÑO:Este fue un estudio observacional.ENTORNO CLINICO:Este fue un análisis post hoc de un ensayo controlado aleatorio, multicéntrico y prospectivo: ensayo RELARC (NCT02619942).PACIENTES:Todos los pacientes incluidos en el análisis de intención de tratar modificado en el ensayo RELARC fueron inscritos en este estudio.PRINCIPALES MEDIDAS DE RESULTADO:Los factores de riesgo de complicaciones posoperatorias se identificaron mediante análisis de regresión logística univariante y multivariable.RESULTADOS:De 995 pacientes, 206 (20,7%) tuvieron complicaciones postoperatorias. La comorbilidad ( p = 0,02, OR: 1,544, IC 95%: 1,077-2,212) y el tiempo operatorio >180 min ( p = 0,03, OR: 1,453, IC 95%: 1,032-2,044) fueron factores de riesgo independientes de complicaciones postoperatorias. Mientras que el sexo femenino ( p = 0,04, OR: 0,704, IC 95%: 0,506-0,980) y la anastomosis extracorpórea ( p < 0,001, OR: 0,251, IC 95%: 0,166-0,378) fueron factores protectores. 80 (8,0%) tenían infección general del sitio quirúrgico (ISQ), 53 (5,3%) tenían ISQ incisional y 33 (3,3%) tenían ISQ de órgano/espacio. Anastomosis latero-lateral fue un factor de riesgo para la ISQ general ( p < 0,001, OR: 1,912, IC 95%: 1,118-3,268) y ISQ órgano/espacio ( p = 0,005, OR: 3,579, IC 95%: 1,455-8.805). La anastomosis extracorpórea se asoció con un riesgo reducido de ISQ general ( p < 0,001, OR: 0,239, IC 95%: 0,138-0,413), ISQ órgano/espacio ( p = 0,002, OR: 0,296, IC 95%: 0,136-0,646), e ISQ incisional ( p < 0,001, OR: 0,179, IC 95%: 0,099-0,322). Diabetes ( p = 0,039, OR: 2,090, IC 95%: 1,039-4,205) y la conversión a cirugía abierta ( p = 0,013, OR: 5,403, IC 95%: 1,437-20,319) fueron factores de riesgo para ISQ incisional.LIMITACIONES:Debido a la naturaleza retrospectiva, la limitación clave es la falta de documentación prospectiva y estandarización sobre el manejo perioperatorio de estos pacientes, como la optimización preoperatoria, los regímenes de preparación intestinal y los regímenes de antibióticos, que pueden ser factores de confusión de las complicaciones. Todas las cirugías fueron realizadas por cirujanos experimentados y los pacientes inscritos eran relativamente jóvenes, generalmente sanos y no obesos. No está claro si los resultados serán generalizables a las poblaciones obesas y de otro tipo en todo el mundo.CONCLUSIONES:Sexo masculino, comorbilidad, el tiempo operatorio prolongado y anastomosis intracorpórea fueron factores de riesgo independientes de complicaciones postoperatorias de la colectomía derecha laparoscópica. Anastomosis latero-lateral se asoció con un mayor riesgo de SSI de órgano/espacio. La anastomosis extracorpórea podría reducir la incidencia de ISQ general. La diabetes y la conversión a cirugía abierta se asociaron con un mayor riesgo de ISQ incisional. (Traducción- Dr. Francisco M. Abarca-Rendon ).

Learning curve and safety of the implementation of laparoscopic complete mesocolic excision with intracorporeal anastomosis for right-sided colon cancer: results from a propensity score-matched study

BACKGROUND

Retrospective studies and randomized controlled trials support the safety of laparoscopic complete mesocolic excision (CME) for the treatment of right-sided colon cancer (RSCC). Few studies, however, examine the learning curve of this operation and its impact on safety during an implementation period. We aim to evaluate the learning curve and safety of the implementation of laparoscopic CME with intracorporeal anastomosis for RSCC.

METHODS

Consecutive patients undergoing a laparoscopic right colectomy with intracorporeal anastomosis for RSCC between January 2016 and June 2023 were included. Clinical, perioperative, and histopathological variables were collected. Correlation and cumulative sum (CUSUM) analyses between the operating time and case number were performed. Breakpoints of the learning curve were estimated using the broken-line model. CME and conventional laparoscopic right colectomy outcomes were compared after propensity score matching (PSM).

RESULTS

Two hundred and ninety patients underwent laparoscopic right colectomy during study period. One hundred and eight met inclusion criteria. After PSM, 56 non-CME and 28 CME patients were compared. CME group had a non-statistically significant tendency to a longer operating time (201 versus 195 min; p = 0.657) and a shorter hospital stay (3 versus 4 days; p = 0.279). No significant differences were found in total complication rates or their profile. Correlation analysis identified a significant trend toward operating time reduction with increasing case numbers (Pearson correlation coefficient =  - 0.624; p = 0.001). According to the CUSUM analysis, an institutional learning curve was deemed completed after 13 cases and the broken-line model identified three phases: learning (1-6 cases), consolidation (7-13 cases), and mastery (after 13 cases).

CONCLUSION

The learning curve of laparoscopic CME for RSCC can be achieved after 13 cases in centers with experience in advanced laparoscopic surgery and surgeons with familiarity with this technique. Its implementation within this setting seems to be as safe as performing a conventional right colectomy.

Extent of Lymphadenectomy for Surgical Management of Right-Sided Colon Cancer: The Randomized Phase III RELARC Trial

PURPOSE

Complete mesocolic excision (CME) is being increasingly used for the treatment of right-sided colon cancer, although there is still no strong evidence that CME provides better long-term oncological outcomes than D2 dissection. The controversy is mainly regarding the survival benefit from extended lymph node dissection emphasized by CME.

METHODS

This multicenter, open-label, randomized controlled trial (ClinicalTrials.gov identifier: NCT02619942) was performed across 17 hospitals in China. Patients diagnosed with stage T2-T4aNanyM0 or TanyN + M0 right-sided colon cancer were randomly assigned (1:1) to undergo either CME or D2 dissection during laparoscopic right colectomy. The primary outcome was the 3-year disease-free survival (DFS), and the main secondary outcome was the 3-year overall survival (OS).

RESULTS

Between January 11, 2016, and December 26, 2019, 1,072 patients were randomly assigned (536 patients to CME and 536 patients to D2 dissection). In total, 995 patients (median age 61 years, 59% male) were included in the primary analysis (CME [n = 495] v D2 dissection [n = 500]). No significant differences were found between the groups in 3-year DFS (hazard ratio [HR], 0.74 [95% CI, 0.54 to 1.02]; P = .06; 86.1% in the CME group v 81.9% in the D2 group) or in 3-year OS (HR, 0.70 [95% CI, 0.43 to 1.16]; P = .17; 94.7% in the CME group v 92.6% in the D2 group).

CONCLUSION

This trial failed to find evidence of superior DFS outcome for CME compared with standard D2 lymph node dissection in primary surgical excision of right-sided colon cancer. Standard D2 dissection should be the routine procedure for these patients. CME should only be considered in patients with obvious mesocolic lymph node involvement.

Laparoscopic right colectomy: correct technique based on key anatomical principles

Since the early1990s, laparoscopic right colon resections have been the most performed advanced laparoscopic procedures just after laparoscopic left colectomies and sigmoid resections. Indications for laparoscopic right colectomies are either benign or malignant diseases. Despite its many indications, a laparoscopic right or extended right colectomy is mostly performed for cancer of the caecum, the ascending colon, the hepatic flexure or the proximal transverse colon. Worldwide, colorectal cancer is the third most diagnosed cancer: an estimated 1,880,725 people were diagnosed with colorectal cancer in 2020, out of which 1,148,515 were colon cancer cases and 40% were located in the right colon. These figures make an oncologic sound surgery for right colon cancer of the utmost relevance. More recently, complete mesocolic excision has been advocated as the optimal choice in term of radicality, especially in node-positive patients with right colon cancer. Laparoscopic standard right colectomy and extended right colectomy with or without CME should be performed according to defined principles based on a close knowledge of key anatomical landmarks. This knowledge will allow to trace anatomical structures and drive instruments along the correct surgical planes and has its foundations in teachings from surgeons and scientists of past and present time.

Comparing cranial-caudal-medial and medial-lateral approaches for laparoscopic right hemicolectomy: a propensity score-matched analysis

BACKGROUND

The cranial-caudal-medial approach (CCMA) has been proposed for laparoscopic right hemicolectomy nowadays. This study aimed to investigate the safety and oncological efficacy of CCMA in the treatment of right-sided colon cancer compared to the medial-lateral approach (MLA).

METHODS

Patients diagnosed with right-sided colon cancer were included from February 2015 to June 2018, retrospectively, dividing into the CCMA group and the MLA group. We compared the basic characteristics and the short-term and long-term outcomes in two groups.

RESULTS

Two hundred and ninety-six patients were included in this study. The baseline characteristics were similar in two groups. Compared with MLA group, CCMA group exhibited shorter operation time (136.3 ± 25.3 min vs. 151.6 ± 21.5 min, P < 0.001), lower estimated blood loss (44.1 ± 15.2 ml vs. 51.4 ± 26.9 min, P = 0.010), and more harvested lymph nodes (18.5 ± 7.1 vs. 16.5 ± 5.7, P = 0.021). The 5-year overall survival (OS) rate for the CCMA group was 76.5%, and the 5-year disease-free survival (DFS) rate was 72.3%, both of which were not inferior to the MLA group. No significant difference was found between two groups in terms of other clinical parameters.

CONCLUSION

The CCMA in laparoscopic right hemicolectomy is safe and feasible, making the anatomical plane clearer. This approach can shorten the operation time, reduce intraoperative blood loss, harvest more lymph nodes, and yield satisfactory oncological outcomes.

The effect of combined head and tail approach during laparoscopic D3 lymph node dissection on pain severity and complications in patients with right colon cancer

OBJECTIVE

To examine the impact of a combined craniocaudal approach on pain and complications during laparoscopic D3 lymph node dissection in clients diagnosed with right colon cancer (RCC).

METHODS

100 RCC patients were divided into Group A and Group B. Both groups underwent laparoscopic D3 lymph node dissection, with Group A undergoing an intermediate approach and Group B undergoing a combined head and tail approach. Two groups of patients' perioperative (surgical time, intraoperative blood loss, number of lymph node dissection) indicators, postoperative recovery (postoperative exhaust time, postoperative hospital stay, drainage tube removal time) indicators, perioperative pain level (VAS scores 1, 3, and 5 days following surgery), and incidence of complications (vascular injury, intestinal obstruction, anastomotic bleeding, incision infection), and the therapeutic efficacy [CEA, CA19-9] indicators were compared.

RESULTS

Clients in the B team had substantially shorter operating times and considerably fewer intraoperative hemorrhage than those in the A team. The VAS grades of clients in the B team were considerably lower than those in the A team the day following surgery. Clients in the B team experienced vascular injury at a substantially lower rate than those in the A team. The overall incidence rate of problems did not differ statistically significantly between the A team and the B team. Following therapy, teams A and B's CEA and CA19-9 levels were considerably lower than those of the same team prior to therapy.

CONCLUSION

Combined craniocaudal technique can significantly reduce intraoperative bleeding, postoperative pain, and the risk of sequelae from vascular injuries.

Comparison of D2 vs D3 lymph node dissection for RIght COloN cancer (RICON): study protocol for an international multicenter open-label randomized controlled trial

BACKGROUND

Colon cancer is a global health concern, ranking fifth in both new diagnoses and deaths among tumors worldwide. Surgical intervention remains the primary treatment for localized cases, with a historical evolution marked by a focus on short-term outcomes. While Japan pioneered radical tumor removal with a systematic categorization of lymph nodes (D1, D2, D3), the dissemination of Japanese practices to the West was delayed until 90th of last century. Discrepancies between Japanese D3 dissection and the CME with CVL principle persist, with variations in longitudinal margins and recommended procedures. Non-randomized trials indicate the superiority of D3 over D2, but a consensus is lacking.

METHODS

This prospective, international, multicenter, randomized controlled trial employs a two-arm, parallel-group, open-label design to rigorously compare the 5-year overall survival outcomes between D2 and D3 lymph node dissection in stage II-III right colon cancer. Building on prior studies, the trial aims to address existing knowledge gaps and provide a comprehensive evaluation of the outcomes associated with D3 dissection. The study population comprises patients with right colon cancer, ensuring a focused investigation into the specific context of this disease. The trial design emphasizes its global scope and collaboration across multiple centers, enhancing the generalizability of the findings.

DISCUSSION

This study's primary objective is to elucidate the potential superiority in 5-year overall survival benefits of D3 lymph node dissection compared to the conventional D2 approach in patients with stage II-III right colon cancer. By examining this specific subset of patients, the research aims to contribute valuable insights into optimizing surgical strategies for improved long-term outcomes. The trial's international and multicenter nature enhances its applicability across diverse populations. The outcomes of this study may inform future guidelines and contribute to the ongoing discourse surrounding the standardization of colon cancer surgery, particularly in the context of right colon cancer.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03200834. Registered on June 27, 2017.

Statistical Fragility in Minimally Invasive Colorectal Surgery Studies: A Review of Randomized Trials

Purpose: The P value has been used as a statistical tool in randomized controlled trials (RCTs) to establish significance but does not provide information on the robustness of a study when used alone. The fragility index (FI) provides a supplemental approach for demonstrating robustness in RCTs that report dichotomous outcomes. This study aims to determine the statistical fragility of RCTs that compare minimally invasive techniques with open techniques in managing benign and malignant colorectal diseases. Methods: Dichotomous outcomes of minimally invasive surgery versus open surgery in RCTs from 2000 to 2023 were assessed. The overall FI and fragility quotient (FQ) of each study were calculated. Results: Of the 1377 screened studies, 50 met the inclusion criteria. In total, 820 outcomes were recorded with 747 outcomes reported as not significant (P ≥ .05) and 73 as significant (P < .05). The overall FI for all studies including all outcomes was 5 (interquartile range [IQR] 4-7) with a FQ of 0.031 (IQR 0.014-0.062). Of the 50 RCTs, 6 (12%) reported a loss to follow-up that was greater than the overall FI of 5. Conclusions: As RCTs are judged increasingly beyond just the P value, practicing colorectal surgeons will benefit from using and interpreting the FI, FQ, and the P value of studies both in analyzing future RCTs and in determining whether or not to make a change in their clinical practice if there is an efficiently true discovery.

Clinical characteristics and risk factors of post-operative intestinal flora disorder following laparoscopic colonic surgery: A propensity-score-matching analysis

BACKGROUND

Intestinal flora disorder (IFD) poses a significant challenge after laparoscopic colonic surgery, and no standard criteria exists for its diagnosis and treatment.

AIM

To analyze the clinical features and risk factors of IFD.

METHODS

Patients with colon cancer receiving laparoscopic surgery were included using propensity-score-matching (PSM) methods. Based on the occurrence of IFD, patients were categorized into IFD and non-IFD groups. The clinical characteristics and treatment approaches for patients with IFD were analyzed. Multivariate regression analysis was performed to identify the risk factors of IFD.

RESULTS

The IFD incidence after laparoscopic surgery was 9.0% (97 of 1073 patients). After PSM, 97 and 194 patients were identified in the IFD and non-IFD groups, respectively. The most common symptoms of IFD were diarrhea and abdominal, typically occurring on post-operative days 3 and 4. All patients were managed conservatively, including modulation of the intestinal flora (90.7%), oral/intravenous application of vancomycin (74.2%), and insertion of a gastric/ileus tube for decompression (23.7%). Multivariate regression analysis identified that pre-operative intestinal obstruction [odds ratio (OR) = 2.79, 95%CI: 1.04-7.47, P = 0.041] and post-operative antibiotics (OR = 8.57, 95%CI: 3.31-23.49, P < 0.001) were independent risk factors for IFD, whereas pre-operative parenteral nutrition (OR = 0.12, 95%CI: 0.06-0.26, P < 0.001) emerged as a protective factor.

CONCLUSION

A stepwise approach of probiotics, vancomycin, and decompression could be an alternative treatment for IFD. Special attention is warranted post-operatively for patients with pre-operative obstruction or early use of antibiotics.

Utility of articulating instruments as an alternative to robotic devices in laparoscopic right hemicolectomy

Laparoscopic complete mesocolic excision with central vessel ligation has been widely accepted for its oncological benefits in colon cancer surgery. However, laparoscopic right hemicolectomy involves a risk for vascular injury during dissection around the surgical trunk. This technical difficulty has been attributed to the limited movement of conventional laparoscopic forceps. Although robotic devices can overcome the restricted motion of laparoscopic devices, they are not yet widely used. The ArtiSential is an articulating laparoscopic instrument that has a two-joint end-effector that enables a wide range of motion precisely reflecting the surgeon's finger movements, and is designed to compensate for the drawbacks of conventional laparoscopic tools. The present study demonstrated the utility of articulating instruments in laparoscopic right hemicolectomy by comparing the authors' laparoscopic procedures, using articulating instruments, with robotic procedures. Articulating laparoscopic instruments can be successfully maneuvered in virtually the same manner as robotic devices and, as such, represent a viable alternative to robotic surgery.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13691-024-00654-w.

Effect of complete mesocolic excision (cme) on long-term survival after right colectomy for cancer: multivariate meta-analysis and restricted mean survival time estimation

INTRODUCTION

Debate exists concerning the impact of complete mesocolic excision (CME) on long-term oncological outcomes. The aim of this review was to condense the updated literature and assess the effect of CME on long-term survival after right colectomy for cancer.

METHODS

PubMed, MEDLINE, Scopus, and Web of Science were searched through July 2023. The included studies evaluated the effect of CME on survival. The primary outcome was long-term overall survival. Restricted mean survival time difference (RMSTD), hazard ratio (HR), and 95% confidence intervals (CI) were used as pooled effect size measures. GRADE methodology was used to summarize the certainty of evidence.

RESULTS

Ten studies (3665 patients) were included. Overall, 1443 (39.4%) underwent CME. The RMSTD analysis shows that at 60-month follow-up, stage I-III CME patients lived 2.5 months (95% CI 1.1-4.1) more on average compared with noCME patients. Similarly, stage III patients that underwent CME lived longer compared to noCME patients at 55-month follow-up (6.1 months; 95% CI 3.4-8.5). The time-dependent HRs analysis for CME vs. noCME (stage I-III disease) shows a higher mortality hazard in patients with noCME at 6 months (HR 0.46, 95% CI 0.29-0.71), 12 months (HR 0.57, 95% CI 0.43-0.73), and 24 months (HR 0.73, 95% CI 0.57-0.92) up to 27 months.

CONCLUSIONS

This study suggests that CME is associated with unclear OS benefit in stage I-III disease. Caution is recommended to avoid overestimation of the effect of CME in stage III disease since the marginal benefit of a more extended resection may have been influenced by tumor biology/molecular profile and multimodal adjuvant treatments.

A Randomized Phase III Trial of Complete Mesocolic Excision Compared with Conventional Surgery for Right Colon Cancer: Interim Analysis of a Nationwide Multicenter Study of the Italian Society of Surgical Oncology Colorectal Cancer Network (CoME-in trial)

BACKGROUND

Although complete mesocolic excision (CME) is supposed to be associated with a higher lymph node (LN) yield, decreased local recurrence, and survival improvement, its implementation currently is debated because the evidence level of these data is rather low and still not supported by randomized controlled trials.

METHOD

This is a multicenter, randomized, superiority trial (NCT04871399). The 3-year disease-free survival (DFS) was the primary end point of the study. The secondary end points were safety (duration of operation, perioperative complications, hospital length of stay), oncologic outcomes (number of LNs retrieved, 3- and 5-year overall survival, 5-year DFS), and surgery quality (specimen length, area and integrity rate of mesentery, length of ileocolic and middle-colic vessels). The trial design required the LN yield to be higher in the CME group at interim analysis.

RESULTS

Interim data analysis is presented in this report. The study enrolled 258 patients in nine referral centers. The number of LNs retrieved was significantly higher after CME (25 vs. 20; p = 0.012). No differences were observed with respect to intra- or post-operative complications, postoperative mortality, or duration of surgery. The hospital stay was even shorter after CME (p = 0.039). Quality of surgery indicators were higher in the CME arm of the study. Survival data still were not available.

CONCLUSIONS

Interim data show that CME for right colon cancer in referral centers is safe and feasible and does not increase perioperative complications. The study documented with evidence that quality of surgery and LN yield are higher after CME, and this is essential for continuation of patient recruitment and implementation of an optimal comparison. Trial registration The trial was registered at ClinicalTrials.gov with the code NCT04871399 and with the acronym CoME-In trial.

Surgical quality assessment for the prospective study of oncologic outcomes after laparoscopic modified complete mesocolic excision for nonmetastatic right colon cancer (PIONEER study)

BACKGROUND

The modified complete mesocolic excision (mCME) procedure for right-sided colon cancer is a tailored approach based on the original complete mesocolic excision (CME) methodology. Limited studies evaluated the safety and feasibility of laparoscopic mCME using objective surgical quality assessments in patients with right colon cancer. The objectives of the PIONEER study were to evaluate oncologic outcomes after laparoscopic mCME and to identify optimal clinically relevant endpoints and values for standardizing laparoscopic right colon cancer surgery based on short-term outcomes of procedures performed by expert laparoscopic surgeons.

MATERIALS AND METHODS

This is an ongoing prospective, multi-institutional, single-arm study conducted at five tertiary colorectal cancer centers in South Korea. Study registrants included 250 patients scheduled for laparoscopic mCME with right-sided colon adenocarcinoma (from the appendix to the proximal half of the transverse colon). The primary endpoint was 3-year disease-free survival. Secondary outcomes included 3-year overall survival, incidence of morbidity in the first 4 weeks postoperatively, completeness of mCME, central radicality, and distribution of metastatic lymph nodes. Survival data will be available after the final follow-up date (June 2024).

RESULTS

The postoperative complication rate was 12.9%, with a major complication rate of 2.7%. In 87% of patients, central radicality was achieved with dissection at or beyond the level of complete exposure of the superior mesenteric vein. Mesocolic plane resection with an intact mesocolon was achieved in 75.9% of patients, as assessed through photographs. Metastatic lymph node distribution varied by tumor location and extent. Seven optimal clinically relevant endpoints and values were identified based on the analysis of complications in low-risk patients.

CONCLUSIONS

Laparoscopic mCME for right-sided colon cancer produced favorable short-term postoperative outcomes. The identified optimal clinically relevant endpoints and values can serve as a reference for evaluating surgical performance of this procedure.

Complete mesocolic excision for colon cancer: current status and controversies

According to Hohenberger's original description, complete mesocolic excision for colon cancer involves precise dissection of the avascular embryonic plane between the parietal retroperitoneum and visceral peritoneum of the mesocolon. This ensures mesocolic integrity, access to high ligation of the supplying vessels at their origin and an associated extended lymphadenectomy. Results from centres which have adopted this approach routinely have demonstrated that oncological outcomes can be improved by the rigorous implementation of established principles of cancer surgery. Meticulous anatomical dissection along embryonic planes is a well-established principle of precision cancer surgery used routinely by the specialist colorectal surgeon. Therefore, the real question concerns the need for true central vascular ligation and associated extended (D3) lymphadenectomy or otherwise, particularly along the superior mesenteric vessels when performing a right colectomy. Whether this approach results in improved overall or disease-free survival remains unclear and its role remains controversial particularly given the potential for significant morbidity associated with a more extensive central vascular dissection. Current literature is limited by considerable bias, as well as inconsistent and variable terminology, and the results of established randomized trials are awaited. As a result of the current state of equipoise, various national guidelines have disparate recommendations as to when complete mesocolic excision should be performed if at all. This article aims to review the rationale for and technical aspects of complete mesocolic excision, summarize available short and long term outcome data and address current controversies.

Laparoscopic right hemicolectomy: a SICE (Società Italiana di Chirurgia Endoscopica e Nuove tecnologie) network prospective study on the approach to right colon lymphadenectomy in Italy: is there a standard?-CoDIG 2 (ColonDx Italian Group)

BACKGROUND

Colon cancer is a disease with a worldwide spread. Surgery is the best option for the treatment of advanced colon cancer, but some aspects are still debated, such as the extent of lymphadenectomy. In Japanese guidelines, the gold standard was D3 dissection to remove the central lymph nodes (203, 213, and 223), but in 2009, Hoenberger et al. introduced the concept of complete mesocolic excision, in which surgical dissection follows the embryological planes to remove the mesentery entirely to prevent leakage of cancer cells and collect more lymph nodes. Our study describes how lymphadenectomy is currently performed in major Italian centers with an unclear indication on the type of lymphadenectomy that should be performed during right hemicolectomy (RH).

METHODS

CoDIG 2 is an observational multicenter national study that involves 76 Italian general surgery wards highly specialized in colorectal surgery. Each center was asked not to modify their usual surgical and clinical practices. The aim of the study was to assess the preference of Italian surgeons on the type of lymphadenectomy to perform during RH and the rise of any new trends or modifications in habits compared to the findings of the CoDIG 1 study conducted 4 years ago.

RESULTS

A total of 788 patients were enrolled. The most commonly used surgical technique was laparoscopic (82.1%) with intracorporeal (73.4%), side-to-side (98.7%), or isoperistaltic (96.0%) anastomosis. The lymph nodes at the origin of the vessels were harvested in an inferior number of cases (203, 213, and 223: 42.4%, 31.1%, and 20.3%, respectively). A comparison between CoDIG 1 and CoDIG 2 showed a stable trend in surgical techniques and complications, with an increase in the robotic approach (7.7% vs. 12.3%).

CONCLUSIONS

This analysis shows how lymphadenectomy is performed in Italy to achieve oncological outcomes in RH, although the technique to achieve a higher lymph node count has not yet been standardized. Trial registration (ClinicalTrials.gov) ID: NCT05943951.

Developing a phantom for simulating robotic-assisted complete mesocolic excision using 3D printing and medical imaging

BACKGROUND

Robotic-assisted complete mesocolic excision is an advanced procedure mainly because of the great variability in anatomy. Phantoms can be used for simulation-based training and assessment of competency when learning new surgical procedures. However, no phantoms for robotic complete mesocolic excision have previously been described. This study aimed to develop an anatomically true-to-life phantom, which can be used for training with a robotic system situated in the clinical setting and can be used for the assessment of surgical competency.

METHODS

Established pathology and surgical assessment tools for complete mesocolic excision and specimens were used for the phantom development. Each assessment item was translated into an engineering development task and evaluated for relevance. Anatomical realism was obtained by extracting relevant organs from preoperative patient scans and 3D printing casting moulds for each organ. Each element of the phantom was evaluated by two experienced complete mesocolic excision surgeons without influencing each other's answers and their feedback was used in an iterative process of prototype development and testing.

RESULTS

It was possible to integrate 35 out of 48 procedure-specific items from the surgical assessment tool and all elements from the pathological evaluation tool. By adding fluorophores to the mesocolic tissue, we developed an easy way to assess the integrity of the mesocolon using ultraviolet light. The phantom was built using silicone, is easy to store, and can be used in robotic systems designated for patient procedures as it does not contain animal-derived parts.

CONCLUSIONS

The newly developed phantom could be used for training and competency assessment for robotic-assisted complete mesocolic excision surgery in a simulated setting.

Complete mesocolic excision and extended lymphadenectomy: Where should we stand?

Debate regarding the risks and merits of complete mesocolic excision and extended lymphadenectomy is ongoing, particularly for right-sided colon cancers. In this article, we hope to provide a succinct yet encompassing review of the relevant literature. We posit that complete mesocolic excision with D3 dissection is indicated in select patients with colon cancers, particularly those distal to the cecum.

[D2 and D3 lymph node dissection for colon cancer]

OBJECTIVE

To evaluate surgical and oncological results of standard and extended lymph node dissection (D2 and D3) in patients with colon cancer.

MATERIAL AND METHODS

We analyzed treatment outcomes in 74 patients with colon cancer stage T1-4aN0-2M0 who underwent right- and left-sided hemicolectomy, resection of sigmoid colon with standard and extended lymph node dissection (D2 and D3).

RESULTS

Surgical approach and level of D3 lymph node dissection did not increase intra- and postoperative morbidity. Laparoscopic interventions were followed by significantly lower intraoperative blood loss and earlier gas discharge. Metastatic lesion of apical lymph nodes was observed in 5 out of 36 patients who underwent D3 lymph node dissection (13.8%), and metastases in regional lymph nodes rN1-2 were found in all these patients. Overall 5-year survival was 86%. Disease-free and overall 5-year survival were similar after D2 and D3 lymph node dissection.

CONCLUSION

D3 lymph node dissection is safe for colon cancer. Metastatic lesions of apical lymph nodes during D3 lymph node dissection were detected only in patients with lesions of regional lymph nodes (rN1-2). Disease-free and overall 5-year survival were similar after D2 and D3 lymph node dissection.

Early recurrence after complete mesocolic excision for right-sided colon cancer with D3 lymphadenectomy: pattern, risk factors, prognostic impact, and individualized follow-up

The definition of early recurrence (ER) for right-sided colon cancer patients after complete mesocolic excision (CME) with D3 lymphadenectomy remains unclear. This study aimed to define the optimal time for ER and clarify risk factors for ER and post-recurrence survival (PRS). A total of 578 right-sided colon cancer patients who underwent CME with D3 lymphadenectomy were included. The minimum p value method was used to evaluate theme optimal time of recurrence-free survival to discriminate between ER and late recurrence (LR). Risk factors for ER were determined by a logistics regression model. The PRS was compared between ER and LR. The optimal time to define ER was 15 months (P = 1.8697E-7). 93 patients developed tumor recurrence, 46 patients had ER (≤15 months) and 47 patients had LR (>15 months). Preoperative serum CA19-9 > 37 U/mL (OR = 3.185, P = 0.001), pathological N+ stage (OR = 3.042, P = 0.027), and lymphovascular invasion (OR = 2.182, P = 0.027) were identified as independent risk factors associated with ER. Age > 75 years (HR = 1.828, P = 0.040), pathological N2 stage (HR = 1.850, P = 0.009), multiple sites of recurrence (HR = 1.680, P = 0.024), and time to recurrence ≤15 months (HR = 2.018, P = 0.043) were significantly associated with worse PRS in patients with recurrence. 15 months was the optimal time to distinguish ER and LR. ER was associated with a poor PRS. Elevated preoperative serum CA19-9 level, pathological N+ stage, and lymphovascular invasion were significantly predictive of ER.

Complete mesocolic excision for right colon cancer: Is D3 lymphadenectomy necessary?

AIM

Although complete mesocolic excision (CME) for colon cancer is oncologically sound, to date, there has been no consensus on the extent of lymphadenectomy in radical right colectomy. This study essentially compared the perioperative and survival outcomes of CME with two templates of lymphadenectomy for right colon cancer.

METHOD

This was a propensity matched, retrospective analysis of a single centre, prospectively maintained database of all patients undergoing elective right colectomy for nonmetastatic, biopsy-proven adenocarcinoma from November 2013 to October 2018. CME + D3 was adopted selectively, documented prospectively, and compared with patients undergoing CME + central vascular ligation (CVL). The only technical difference between the groups was the excision of the surgical trunk of Gillot in the CME + D3 group. Postoperative, long-term outcomes and patterns of recurrence were compared between the groups.

RESULTS

Of the 244 eligible patients, 88 (36.1%) and 156 (63.9%) underwent CME + D3 and CME + CVL, respectively. Matched groups (72 [CME + D3] vs. 108 [CME + CVL]) showed no difference in histology, tumour grade, postoperative complications, mortality, and hospital stay. CME + D3 was preferentially performed laparoscopically (35.2% vs. 9%), was associated with lower blood loss (215 mL vs. 297 mL, p = 0.001), higher nodal yield (31 vs. 25 nodes, p = 0.003) and a higher incidence of chyle leak (4 vs. 0, p = 0.013). At a median follow-up of more than 57 months, there was no significant difference in local recurrence, disease-free or overall survival.

CONCLUSION

In this retrospective study, lymphadenectomy along the superior mesenteric vein, as a component of CME for right colon cancer, offered a higher nodal yield with no improvement in oncological outcome. Dissection of the SMV, over and above a D2 dissection, could therefore be restricted to specialized colorectal units until further studies establish the incremental oncological benefit of this extended lymphadenectomy or define a patient group in whom it is beneficial.

Tata Memorial Centre Evidence Based Management of Colorectal cancer

ABSTRACT

This review article examines the evidence-based management of colorectal cancers, focusing on topics characterized by ongoing debates and evolving evidence. To contribute to the scientific discourse, we intentionally exclude subjects with established guidelines, concentrating instead on areas where the current understanding is dynamic. Our analysis encompasses a thorough exploration of critical themes, including the evidence surrounding complete mesocolic excision and D3 lymphadenectomy in colon cancers. Additionally, we delve into the evolving landscape of perioperative chemotherapy in both colon and rectal cancers, considering its nuanced role in the context of contemporary treatment strategies. Advancements in surgical techniques are a pivotal aspect of our discussion, with an emphasis on the utilization of minimally invasive approaches such as laparoscopy and robotic surgery in both colon and rectal cancers, including advanced rectal cases. Moving beyond conventional radical procedures, we scrutinize the feasibility and implications of endoscopic resections for small tumors, explore the paradigm of organ preservation in locally advanced rectal cancers, and assess the utility of total neoadjuvant therapy in the current treatment landscape. Our final segment reviews pivotal trials that have significantly influenced the management of colorectal liver and peritoneal metastasis.

Association of hemicolectomy with survival in stage II colorectal cancer: a retrospective cohort study

To compare the oncological survival outcomes of partial colectomy (PC) and hemicolectomy (HC) in patients with stage II colon cancer. A total of 18,795 patients with stage II colon cancer who underwent hemicolectomy (n = 12,022) or partial colectomy (n = 6773) from 2010 to 2019 were included in the the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific survival (CSS) were compared between the two groups, and the threshold of harvested lymph nodes was determined. The results showed that age, gender, race, tumor site, scope of regional lymph nodes, postoperative chemotherapy, postoperative radiotherapy, harvested lymph nodes, and tumor size were significantly different between the PC and HC groups (all P < 0.05). The OS rate was slightly lower in hemicolectomy patients than in partial colectomy patients (69.9% vs. 74.5%, respectively, P < 0.001), but CSS was similar between the two groups (87.9% vs. 88.1%, respectively, P = 0.32). After propensity score matching (PSM) was performed, the OS and CSS rates in the two groups were significantly different (CSS 84.3% vs. 88.0%, P < 0.001; OS 62.2% vs. 72.5%, P < 0.001). The survminer R package determined that the optimum threshold for the harvested lymph node count in stage II colon cancer patients was 16. CSS was significantly different between patients with ≥ 12 lymph nodes harvested and patients with ≥ 16 lymph nodes harvested (P = 0.043). Univariate and multivariate Cox regression and survival analyses of stage II colon cancer patients showed that the survival benefit of stage II colon cancer patients receiving partial colectomy was superior to that of patients receiving hemicolectomy. Partial colectomy has significant oncological benefits over hemicolectomy in the treatment of stage II colon cancer patients, even in the case of pT4b or tumor deposits. Removal of 16 lymph nodes during colectomy for stage II colon cancer correlated with improved survival, and this threshold was more effective than the standard threshold of 12 lymph nodes in distinguishing between patients with good and poor prognoses.

Best Evidence for Each Surgical Step in Minimally Invasive Right Hemicolectomy: A Systematic Review

Objective

The aim of this study was to systematically review the literature for each surgical step of the minimally invasive right hemicolectomy (MIRH) for non-locally advanced colon cancer, to define the most optimal procedure with the highest level of evidence.

Background

High variability exists in the way MIRH is performed between surgeons and hospitals, which could affect patients' postoperative and oncological outcomes.

Methods

A systematic search using PubMed was performed to first identify systematic reviews and meta-analyses, and if there were none then landmark papers and consensus statements were systematically searched for each key step of MIRH. Systematic reviews were assessed using the AMSTAR-2 tool, and selection was based on highest quality followed by year of publication.

Results

Low (less than 12 mmHg) intra-abdominal pressure (IAP) gives higher mean quality of recovery compared to standard IAP. Complete mesocolic excision (CME) is associated with lowest recurrence and highest 5-year overall survival rates, without worsening short-term outcomes. Routine D3 versus D2 lymphadenectomy showed higher LN yield, but more vascular injuries, and no difference in overall and disease-free survival. Intracorporeal anastomosis is associated with better intra- and postoperative outcomes. The Pfannenstiel incision gives the lowest chance of incisional hernias compared to all other extraction sites.

Conclusion

According to the best available evidence, the most optimal MIRH for colon cancer without clinically involved D3 nodes entails at least low IAP, CME with D2 lymphadenectomy, an intracorporeal anastomosis and specimen extraction through a Pfannenstiel incision.

Complete mesocolic excision versus standard resection for colon cancer: a systematic review and meta-analysis of perioperative safety and an evaluation of the use of a robotic approach

PURPOSE

Complete mesocolic excision (CME) has been associated with improved oncological outcomes in treatment of colon cancer. However, widespread adoption is limited partly because of the technical complexity and perceived risks of the approach. The aim of out study was to evaluate the safety of CME compared to standard resection and to compare robotic versus laparoscopic approaches.

METHODS

Two parallel searches were undertaken in MEDLINE, Embase and Web of Science databases 12 December 2021. The first was to evaluate IDEAL stage 3 evidence to compare complication rates as a surrogate marker of perioperative safety between CME and standard resection. The second independent search compared lymph node yield and survival outcomes between minimally invasive approaches.

RESULTS

There were four randomized control trials (n = 1422) comparing CME to standard resection, and three studies comparing laparoscopic (n = 164) to robotic (n = 161) approaches. Compared to standard resection, CME was associated with a reduction in Clavien-Dindo grade 3 or higher complication rates (3.56% vs. 7.24%, p = 0.002), reduced blood loss (113.1 ml vs. 137.6 ml, p < 0.0001) and greater mean lymph node harvest (25.6 vs. 20.9 nodes, p = 0.001). Between the robotic and laparoscopic groups, there were no significant differences in complication rates, blood loss, lymph node yield, 5-year disease-free survival (OR 1.05, p = 0.87) and overall survival (OR 0.83, p = 0.54).

CONCLUSIONS

Our study demonstrated improved safety with CME. There was no difference in safety or survival outcomes between robotic and laparoscopic CME. The advantage of a robotic approach may lie in the reduced learning curve and an increased penetration of minimally invasive approach to CME. Further studies are required to explore this.

PROSPERO ID

CRD42021287065.

A multicenter prospective observational study of lymph node metastasis patterns and short-term outcomes of extended lymphadenectomy in right-sided colon cancer

Background

The lymph node metastasis rate in right-sided colon cancer is unknown, and the optimal central vascular ligation level remains controversial. We aimed to determine the lymph node metastasis rate and short-term results of radical surgery with extended lymph node dissection in right-sided colon cancer.

Methods

This prospective multicenter observational study included patients with stage II/III right-sided colon cancer from five cancer hospitals. The metastasis rate of each node station was analyzed according to tumor location and main feeding artery.

Results

Between April 2018 and August 2021, 208 patients underwent dissection around the superior mesenteric artery (SMA) and vein (SMV). In transverse colon cancer, 7.5% and 2.5% of metastases occurred around the SMV and SMA at the root of the middle colic artery (MCA), respectively; 6.7% and 6.7% at the root of the right colic artery. In caecal cancer, 1.9% of metastases occurred around the SMV and 1.9% around the SMA. In ascending colon cancer, the rate was 1.1% around the SMV. Of the tumors, 17% fed mainly by the ileocolic artery had node metastases along the middle or right colic artery, as did 66.7% fed mainly by the right colic artery and 41.2% fed by the MCA (p = 0.01). Postoperative complications occurred in 42 patients (20.2%).

Conclusion

Routine prophylactic extended lymphadenectomy around the SMA might not be necessary in caecum and ascending colon cancer. Dissection around the SMA may be necessary in cases of transverse colon cancer or when the feeding artery is the MCA.

Complete mesocolic excision for right hemicolectomy: an updated systematic review and meta-analysis

PURPOSE

Complete mesocolic excision improves lymphadenectomy for right hemicolectomy and respects the embryological planes. However, its effect on cancer-free and overall survival is questioned. Therefore, we aimed to determine the potential benefits of the technique by performing a systematic review of the literature and meta-analysis of the available evidence.

METHODS

Web of Science, PubMed/Medline, and Embase were searched on February 22, 2023. Original studies on short- and long-term oncological outcomes of adult patients undergoing right hemicolectomy with complete mesocolic excision as a treatment for primary colon cancer were considered for inclusion. Outcomes were extracted and pooled using a model with random effects.

RESULTS

A total of 586 publications were identified through database searching, and 18 from citation searching. Exclusion of 552 articles left 24 articles for inclusion. Meta-analysis showed that complete mesocolic excision increased the lymph node harvest (5 studies, 1479 patients, MD 9.62, 95% CI 5.83-13.41, p > 0.0001, I2 84%), 5-year overall survival (5 studies, 2381 patients, OR 1.88, 95% CI 1.14-3.09, p = 0.01, I2 66%), 5-year disease-free survival (4 studies, 1376 patients, OR 2.21, 95% CI 1.51-3.23, p < 0.0001, I2 0%) and decreased the incidence of local recurrence (4 studies, 818 patients, OR 0.27, 95% CI 0.09-0.79, p = 0.02, I2 0%) when compared to standard right hemicolectomy. Perioperative morbidity was similar between the techniques (8 studies, 3899 patients, OR 1.04, 95% CI 0.89-1.22, p = 0.97, I2 0%).

CONCLUSION

Meta-analysis of observational and randomised studies showed that right hemicolectomy with complete mesocolic excision for primary right colon cancer improves oncologic results without increasing morbidity/mortality. These results need to be confirmed by high-quality evidence and randomised trials in selected patients to assess who may benefit from the procedure.

Preoperative Local Staging of Colon Cancer by CT: Radiological Staging Criteria Based on Membrane Anatomy and Visceral Adipose Tissue

BACKGROUND

Accuracy of preoperative T staging for colon cancer remains disappointing.

OBJECTIVE

This study aimed to propose specially designed radiological staging criteria based on membrane anatomy and visceral adipose tissue and compare the staging performance with the routinely used method.

DESIGN

This is a prospective observational study.

SETTING

This study was conducted at a high-volume colorectal center.

PARTICIPANTS

Consecutive patients with colonoscopy-proven colon carcinoma referred for clinical staging and elective resection were enrolled.

INTERVENTION

The preoperative CT data were separately reviewed by 2 teams of radiologists for assigning T-stage categories (T1-2, T3, or T4) using the routine staging method or the newly proposed radiological criteria.

MEASURES

Diagnostic performance for T staging was compared between the 2 criteria.

RESULTS

Between October 2019 and August 2020, 190 patients were included. Compared with pathological results, T stage was correctly determined in 113 of 190 patients (59.5%) with the conventional CT criteria. With the newly developed criteria, 160 patients (84.2%) were found to be correctly staged. Accuracies between the 2 criteria significantly differed ( p < 0.001). For T1-2 staging, there were no significant differences between the sensitivities of conventional and new criteria (57.1% vs 61.9%; p = 0.990) or between their specificities (95.3% vs 98.2%; p = 0.131). However, for T3 and T4 staging, the newly developed CT criteria exhibited significantly higher sensitivity (T3: 85.2% vs 57.4%; p < 0.001; T4: 90.7% vs 64.8%; p < 0.001) and specificity (T3: 82.7% vs 64%; p = 0.006; T4: 89.7% vs 69.1%; p < 0.001) than the conventional criteria. Moreover, the new criteria (area under the curve = 0.902) performed significantly better than the conventional criteria (area under the curve = 0.670; p < 0.001), for identifying the T4-stage tumor.

LIMITATIONS

The limitations are that it is a single-center study and there was no external validation.

CONCLUSIONS

The specially designed radiological criteria can offer more accurate T staging than the routine method in colon cancer. See Video Abstract at http://links.lww.com/DCR/B992 .

PREDICCIN DE LA MORTALIDAD A DAS POSTERIORES A LA PRIMERA CIRUGA EN PACIENTES CON CNCER DE COLON OBSTRUCTIVO DEL LADO IZQUIERDO

ANTECEDENTES:Se cree que la resección aguda para el carcinoma de colon obstructivo del lado izquierdo está asociada con un mayor riesgo de mortalidad que un enfoque puente a la cirugía que utiliza un estoma de descompresión o un stent metálico autoexpandible, pero faltan modelos de predicción.OBJETIVO:Determinar la influencia de la estrategia de tratamiento sobre la mortalidad dentro de los 90 días desde la primera intervención utilizando un modelo de predicción en pacientes que presentan carcinoma de colon obstructivo del lado izquierdo.DISEÑO:Un estudio de cohorte multicéntrico nacional, utilizando datos de una auditoría nacional prospectiva.ENTORNO CLINICO:El estudio se realizó en 75 hospitales holandeses.PACIENTES:Se incluyeron los pacientes que se sometieron a una resección con intención curativa de un carcinoma de colon obstructivo del lado izquierdo entre 2009 y 2016.INTERVENCIONES:La primera intervención fue resección aguda, puente a cirugía con stent metálico autoexpandible o puente a cirugía con estoma descompresor.PRINCIPALES MEDIDAS DE VALORACIÓN:La principal medida de resultado fue la mortalidad a los 90 días después de la primera intervención. Los factores de riesgo se identificaron mediante análisis logístico multivariable. Posteriormente se desarrolló un modelo de riesgo.RESULTADOS:En total se incluyeron 2395 pacientes, siendo la primera intervención resección aguda en 1848 (77%) pacientes, estoma como puente a la cirugía en 332 (14%) pacientes y stent como puente a la cirugía en 215 (9%) pacientes. En general, 152 pacientes (6,3%) fallecieron dentro de los 90 días posteriores a la primera intervención. Un estoma de descompresión se asoció de forma independiente con un menor riesgo de mortalidad a los 90 días (HR: 0,27, IC: 0,094-0,62). Otros predictores independientes de mortalidad fueron la edad, la clasificación ASA, la ubicación del tumor y los niveles índice de creatinina sérica y proteína C reactiva. El modelo de riesgo construido tuvo un área bajo la curva de 0,84 (IC: 0,81-0,87).LIMITACIONES:Solo se incluyeron pacientes que se sometieron a resección quirúrgica.CONCLUSIONES:La estrategia de tratamiento tuvo un impacto significativo en la mortalidad a los 90 días. Un estoma descompresor reduce considerablemente el riesgo de mortalidad, especialmente en pacientes mayores y frágiles. Se desarrolló un modelo de riesgo, que necesita una mayor validación externa. Consulte Video Resumen en http://links.lww.com/DCR/B992 . (Traducción-Dr. Ingrid Melo ).

Right Colectomy with Intracorporeal Anastomosis: A European Multicenter Propensity Score Matching Retrospective Study of Robotic Versus Laparoscopic Procedures

BACKGROUND

This study aimed to compare the short- and long-term outcomes of robotic (RRC-IA) versus laparoscopic (LRC-IA) right colectomy with intracorporeal anastomosis using a propensity score matching (PSM) analysis based on a large European multicentric cohort of patients with nonmetastatic right colon cancer.

METHODS

Elective curative-intent RRC-IA and LRC-IA performed between 2014 and 2020 were selected from the MERCY Study Group database. The two PSM-groups were compared for operative and postoperative outcomes, and survival rates.

RESULTS

Initially, 596 patients were selected, including 194 RRC-IA and 402 LRC-IA patients. After PSM, 298 patients (149 per group) were compared. There was no statistically significant difference between RRC-IA and LRC-IA in terms of operative time, intraoperative complication rate, conversion to open surgery, postoperative morbidity (19.5% in RRC-IA vs. 26.8% in LRC-IA; p = 0.17), or 5-yr survival (80.5% for RRC-IA and 74.7% for LRC-IA; p = 0.94). R0 resection was obtained in all patients, and > 12 lymph nodes were harvested in 92.3% of patients, without group-related differences. RRC-IA procedures were associated with a significantly higher use of indocyanine green fluorescence than LRC-IA (36.9% vs. 14.1%; OR: 3.56; 95%CI 2.02-6.29; p < 0.0001).

CONCLUSION

Within the limitation of the present analyses, there is no statistically significant difference between RRC-IA and LRC-IA performed for right colon cancer in terms of short- and long-term outcomes.

Comparison of short-term outcomes between robotic and laparoscopic distal gastrectomy performed by the same surgical team during the same period

Objective

To evaluate the short-term outcomes of laparoscopic distal gastrectomy and robotic distal gastrectomy performed during the same period.

Methods

This study enrolled 46 cases of laparoscopic distal gastrectomy and 67 cases of robotic distal gastrectomy that were performed by a single surgeon between April 2020 to October 2021. Baseline characteristics and short-term outcomes of these two groups were then compared. Moreover, the robotic distal gastrectomy group was further divided into two subgroups according to the learning curve. Finally, the baseline characteristics and short-term outcomes of both subgroups were compared with the laparoscopic group, respectively.

Results

The baseline characteristics and short-term outcomes of the LDG group and RDG group were comparable. In contrast, the operation time in the laparoscopic group was significantly shorter than that in the early experience robotic group (191.3 ± 37.6 VS 225.1 ± 49, P=0.001). However, the operation time (191.3 ± 37.6 VS 185.3 ± 25.3, P=0.434) was comparable between the laparoscopic group and the late experience robotic group. Likewise, the bleeding volume was comparable between the laparoscopic and early experience robotic groups. However, bleeding volume was significantly lower in the late experience robotic group compared to that in the laparoscopic group (37.5 ± 18.8 VS 49.2 ± 29.0, P=0.049).

Conclusions

With surgeons stepping into the stable stage of the robotic learning curve, RDG showed a comparable operation time and lower volume of blood loss compared with LDG. Collectively, our study supports the application of robotic distal gastrectomy in patients diagnosed with gastric cancer.

Young adults with colon cancer: clinical features and surgical outcomes

BACKGROUND

The clinicopathological features, surgical outcomes, and long-term survival of patients with young-onset colon cancer (≤ 40 years old) remain controversial.

METHODS

The clinicopathologic and follow-up data of patients aged < 40 years with colon cancer between January 2014 and January 2022 were reviewed. The primary objectives were clinical features and surgical outcomes. Long-term survival was investigated as a secondary objective.

RESULTS

Seventy patients were included in the study, and no significant rising trend (Z=0, P=1) of these patients was observed over the 8-year study period. Stage IV disease was accompanied by more ulcerative or infiltrating type (84.2% vs. 52.9%, P=0.017) and lymphovascular or perineural invasion (64.7% vs. 25.5%, P=0.003) than stage I-III disease. After a median follow-up time of 41 months (range 8-99 months), the 1-, 3-, and 5-year estimated overall survival (OS) rates were 92.6%, 79.5%, and 76.4%, respectively. The 1-, 3-, and 5-year progression-free survival (PFS) rates were 79.6%, 71.7%, and 71.7%, respectively. Multivariate Cox regression showed that M+ stage (hazard ratio [HR], 3.942; 95% confidence interval [CI], 1.176-13.220, P=0.026) was the only independent risk factor affecting OS. Meanwhile, tumor deposits (HR, 4.807; 95% CI, 1.942-15.488, P=0.009), poor differentiation (HR, 2.925; 95% CI, 1.012-8.454, P=0.047), and M+ stage (HR, 3.540; 95% CI, 1.118-11.202, P=0.032) independently affected PFS.

CONCLUSIONS

The differences in the clinical features, surgical outcomes, and long-term survival between young adults and elderly colon cancer patients need further investigation.

Prognostic immunogenic characteristics of iron pendant disease modifiers in colon cancer

Background

We explored the prognostic and immunogenic characteristics of iron pendant disease regulators in colon cancer to provide a scientific basis for the prediction of tumor prognosis-related markers and potential immunotherapeutic drug targets.

Methods

RNA sequencing and matched complete clinical information of colon cancer (COAD) were retrieved from the UCSC Xena database, and genomic and transcriptomic data of colon cancer from the TCGA database were downloaded. Then univariate and multifactorial Cox regression were used to process these data. The prognostic factors were analyzed by single-factor and multi-factor Cox regression, followed by Kaplan-Meier survival curves with the aid of R software "survival" package. Then we use FireBrowse online analysis tool to analyze the expression variation of all cancer genes, and draw a histogram according to the influencing factors to predict the 1, 3, and 5 year survival rates of patients.

Results

The results show that age, tumor stage and iron death score were significantly correlated with prognosis (p<0.05). Further multivariate cox regression analysis confirmed that age, tumor stage and iron death score were still significantly correlated with prognosis (p<0.05); The calibration curve results show that the deviation between the predicted values of 1 year, 3 years and 5 years and the diagonal of the figure is very small; the ROC curve results show that the AUC values of the 1-year and 5-year ROC curves of the bar graph are high; the DCA curve results show that the net yield of the bar graph is the largest; The scores of T cells and B cells in the high iron death score group were significantly lower than those in the low iron death score group, and the activities of immune related pathways were significantly reduced. There was a significant difference in the iron death score between the iron death molecular subtype and the gene cluster subtype.

Conclusions

The model showed a superior response to immunotherapy in the high-risk group, revealing a potential relationship between iron death and tumor immunotherapy, which will provide new ideas for the treatment and prognostic assessment of colon cancer patients.

Intracorporeal versus extracorporeal anastomosis in laparoscopic right colectomy: a retrospective study

BACKGROUND

The surgical procedure for laparoscopic right colectomy (LRC) is not standardized. Some published studies show the superiority of ileocolic anastomosis (IIA), but the evidence so far is insufficient. This study aimed to investigate the potential advantages in postoperative recovery and safety of IIA in LRC.

METHODS

A total of 114 patients who underwent LRC with IIA (n = 58) or extracorporeal ileocolic anastomosis (EIA, n = 56) between January 2019 and September 2021 were enrolled. We collected certain factors as clinical features, intraoperative characteristics, oncological outcomes, postoperative recovery, and short-term outcomes. Our primary outcome was time to gastrointestinal (GI) function recovery. Secondary outcomes were postoperative complications within 30 days, postoperative pain, and length of hospital stay.

RESULTS

Faster GI recovery and less postoperative pain were observed in patients with IIA compared to EIA [time to first flatus: (2.4 ± 0.7) vs (2.8 ± 1.0) days, p < 0.01; time to liquid intake: (3.5 ± 0.7) vs (4.0 ± 1.1) days, p = 0.01; postoperative visual analogue scale score: (3.9 ± 1.0) vs (4.3 ± 0.6), p = 0.02]. No significant differences were detected in oncological outcomes or postoperative complications. IIA, rather than EIA, tended to be performed in patients with higher body mass index [(23.93 ± 3.52) vs (22.36 ± 2.87) kg/m², p = 0.01].

CONCLUSIONS

IIA is associated with faster GI function recovery and less postoperative pain and may be more favorable for obese patients.

Current Controversies in the Management of Locally Advanced Colon Cancer

n/a.

Bach Mai Procedure for complete mesocolic excision, central vascular ligation, and D3 lymphadenectomy in total laparoscopic right hemicolectomy: a prospective study

PURPOSE

Total laparoscopic right hemicolectomy with complete mesocolic excision (CME), central vascular ligation (CVL), and D3 lymphadenectomy is still the most challenging colon procedures for gastrointestinal surgeons. We herein report the technical details and our preliminary experience of Bach Mai Procedure - a novel-combining (cranial, medial to lateral, and caudal) approach with early resection of the terminal ileum.

METHODS

The dissection stage was central vascular isolation and ligation by a combined multiple approaches in the following four steps: cranial approach, dissecting along the inferior aspect of pancreatic isthmus to reveal the middle colic vessels and the anterior aspect of the superior mesentery vein and then exposed the right gastroepiploic vein and the trunk of Henle; medial-to-lateral approach, exposing the surgical axis - the superior mesenteric vascular axis and then early resection of the terminal ileum to open the dissection from the bottom up; and caudal approach, radical ligation of the ileocecal artery and right colic artery (central vascular ligation), lymph node dissection (D3 lymphadenectomy), and resecting the Toldt fascia of the colon to release the entire right colon from the abdominal wall.

RESULTS

In 12 months, there were 32 cases of primary right-sided colon malignancies that have undergone tLRH_{D3, CME/CVL} based on the Bach Mai Procedure. In 3 cases (9.4%), the tumor site was hepatic flexure. The median of lymph node number (LNN) was 38, with the maximum number which was 101. No serious postoperative complications (grade 3 or higher) neither inhospital mortality was detected.

CONCLUSION

This Bach Mai procedure, a novel-combining approach with early resection of the terminal ileum, is technically feasible and safe for tLRH_{D3, CME/CVL}. Further investigations and follow-up must be proceeded to evaluate the long-term outcomes of our technique.

Comparison of survival outcomes between laparoscopic and open colectomy for transverse colon cancer: a systematic review and meta-analysis

PURPOSE

This study aimed to compare laparoscopic with open resection for transverse colon cancer (TCC) regarding long-term survival outcomes.

METHODS

Systematic literature search was performed on PubMed, Ovid, and Cochrane Library for studies comparing laparoscopic with open resection for TCC. The last search was performed on October 7, 2022. Oncological and survival outcomes were collected and analyzed. This meta-analysis was performed using Review Manager Software (v 5.3).

RESULTS

This study included fifteen studies published between 2014 and 2022 with 2556 patients in total. When compared with the laparoscopic group, the open group had significantly more tumors locating on middle transverse colon (P = 0.006, OR = 0.67, 95%CI [0.50, 0.89], I² = 12%) and more patients received transverse colectomy (P = 0.03, OR = 0.66, 95%CI [0.46, 0.96], I² = 53%) as results. Comparable tumor stage (P = 0.13, OR = 0.81, 95%CI [0.62, 1.06], I² = 55%) and number of lymph node harvested (P = 0.22, WMD =  -0.81, 95%CI [-2.09, 0.47], I² = 73%) were observed between the two groups. As for survival outcomes, no significant difference was observed between the two groups for 5-year disease-free survival (DFS; P = 0.61, OR = 0.93, 95%CI [0.72, 1.21], I² = 0%), 5-year overall survival (OS; P = 0.83, OR = 0.97, 95%CI [0.71, 1.32], I² = 0%), 3-year DFS (P = 0.97, OR = 0.96, 95%CI [0.69, 1.32], I² = 0%), and 3-year OS (P = 0.67, OR = 0.92, 95%CI [0.63, 1.35], I² = 0%). In the subgroup analysis according to tumor stage, the results did not change.

CONCLUSION

Current evidence based on studies demonstrated that laparoscopic procedure could be safely performed for TCC, and it would not affect the long-term survival. Randomized clinical trials with a larger sample size are warranted in the future for further investigation.

Surgical efficacy and learning curves of laparoscopic complete mesocolic excision with intracorporeal anastomosis for right-sided colon cancer: A retrospective two-center cohort study

BACKGROUND

There is a potential benefit on long-term outcomes following complete mesocolic excision (CME) for right-sided colon cancer when compared to conventional colectomy. This study aims to analyze the learning curve and short-term outcomes of laparoscopic CME with intracorporeal anastomosis (ICA) for right-sided colon cancer in the hands of experienced colorectal surgeons.

METHODS

A two-center cohort study of consecutive patients undergoing right-sided colectomy from September 2021 to May 2022 at two tertiary colorectal centers in Denmark. Learning curves of surgical time were estimated using a cumulative sum analysis (CUSUM).

RESULTS

A total of 61 patients were included. According to the CUSUM analysis, 32 cases were needed to obtain a peak in operative time, resulting in a decrease in time consumption (group 1/learning phase: 217.2 min [SD 53.6] and group 2/plateau phase 191.6 min [SD 45.1], p = 0.05). There was a nonsignificant reduction in the rates of severe surgical complications (Clavien-Dindo > 3) (13% vs. 7%, p = 0.67) between the two groups, while the length of hospital stay remained constant (median 3.0 days, interquartile range, IQR [2.0; 4.0]).

CONCLUSION

The learning curve of laparoscopic CME with ICA for right-sided colon cancer demonstrated that 32 cases were needed to obtain a plateau phase expressed by operative time.