No benefit of extended mesenteric resection with central vascular ligation in right-sided colon cancer

Are Metastatic Central Lymph Nodes (D3 volume) in right-sided Colon Cancer a Sign of Systemic Disease? A sub-group Analysis of an Ongoing Multicenter Trial

OBJECTIVE

Assess outcomes of patients with right-sided colon cancer with metastases in the D3 volume after personalized surgery.

BACKGROUND

Patients with central lymph node metastasis (D3-PNG) are considered to have a systemic disease with a poor prognosis. A 3-dimensional definition of the dissection volume allows the removal of all central nodes.

MATERIALS AND METHODS

D3-PNG includes consecutive patients from an ongoing clinical trial. Patients were stratified into residual disease negative (D3-RDN) and residual disease positive (D3-RDP) groups. D3-RDN was further stratified into 4 periods to identify a learning curve. A personalized D3 volume (defined through arterial origins and venous confluences) was removed " en bloc" through medial-to-lateral dissection, and the D3 volume of the specimen was analyzed separately.

RESULTS

D3-PNG contained 42 (26 females, 63.1 SD 9.9 y) patients, D3-RDN:29 (17 females, 63.4 SD 10.1 y), and D3-RDP:13 (9 females, 62.2 SD 9.7 y). The mean overall survival (OS) days were D3-PNG:1230, D3-RDN:1610, and D3-RDP:460. The mean disease-free survival (DFS) was D3-PNG:1023, D3-RDN:1461, and D3-RDP:74 days. The probability of OS/DFS were D3-PNG:52.1%/50.2%, D3-RDN:72.9%/73.1%, D3-RDP: 7.7%/0%. There is a significant change in OS/DFS in the D3-RDN from 2011-2013 to 2020-2022 (both P =0.046) and from 2014-2016 to 2020-2022 ( P =0.028 and P =0.005, respectively).

CONCLUSION

Our results indicate that surgery can achieve survival in most patients with central lymph node metastases by removing a personalized and anatomically defined D3 volume. The extent of mesenterectomy and the quality of surgery are paramount since a learning curve has demonstrated significantly improved survival over time despite the low number of patients. These results imply a place for the centralization of this patient group where feasible.

Management of Surgically Accessible Lymph Nodes Beyond Normal Resection Planes

This article discusses the management of isolated metastatic lymph nodes for colon and rectal cancer. There are traditionally significant differences in how certain regions of lymph nodes for colon and rectal cancer are managed in the East and West. This has led to the development of the lateral lymph node dissection for rectal cancer and extended lymphadenectomy techniques for colon cancer. This article will evaluate the literature on these techniques and what the surgical and oncological outcomes are at this time. In addition, colon and rectal cancers can occasionally have isolated distant lymph node metastases. These would traditionally be treated as systemic disease with chemotherapy. There is consideration though that these could be treated as similar to isolated liver or lung metastases which have been shown to be able to be treated surgically with good oncological results. The literature for these isolated distant lymph node metastases will be reviewed and treatment options available will be discussed.

Pathways of lymph node metastasis and prognosis after right hemicolectomy for cecal cancer: results from a retrospective single center

BACKGROUND

The recommended operation for cecum cancer (CC) is right hemicolectomy (RH) in some Western countries while the principle of D3 lymphadenectomy in Japan recommends resecting approximately 10 cm from the tumor edge. Therefore, the optimal surgical approach for cecum cancer (CC) remains controversial. We conducted this retrospective study to explore the pattern of lymph node metastasis and better surgical procedures for CC.

METHODS

A total of 224 cecum cancer patients from January 1, 2014, to December 31, 2021, were retrospectively included in the final study. The pattern of lymph node metastasis (LNM) was investigated.

RESULTS

A total of 113 (50.4%, 113/224) patients had pathologically confirmed LNM. The most frequent metastatic site was no. 201 lymph node (46%, 103/224), while 20 (8.9%, 20/224) patients had LNM in no. 202 lymph node, and 8 (3.6%, 8/224) patients had LNM in no. 203 lymph node. Only 1 (0.4%, 1/224) patient had LNM in no. 221 lymph node, four (1.8, 4/224%) patients had LNM in no. 223 lymph node, and no patients had LNM in no. 222 lymph node. LNM in no. 223 lymph node was significantly associated with a poor prognosis. Multivariate analysis indicated that LNM in no. 223 lymph node (HR = 4.59, 95% CI 1.18-17.86, P = 0.028) was the only independent risk factor associated with worse disease-free survival (DFS).

CONCLUSIONS

The LNM in no. 223 lymph node for cecum cancer was rare. Therefore, standard right hemicolectomy excision is too extensive for most CC cases.

Macroscopic Evaluation of Colon Cancer Resection Specimens

Colon cancer is a common disease internationally. Outcomes have not improved to the same degree as in rectal cancer, where the focus on total mesorectal excision and pathological feedback has significantly contributed to improved survival and reduced local recurrence. Colon cancer surgery shows significant variation around the world, with differences in mesocolic integrity, height of the vascular ligation and length of the bowel resected. This leads to variation in well-recognised quality measures like lymph node yield. Pathologists are able to assess all of these variables and are ideally placed to provide feedback to surgeons and the wider multidisciplinary team to improve surgical quality over time. With a move towards complete mesocolic excision with central vascular ligation to remove the primary tumour and all mechanisms of spread within an intact package, pathological feedback will be central to improving outcomes for patients with operable colon cancer. This review focusses on the key quality measures and the evidence that underpins them.

Extended Right-Sided Colon Resection Does Not Reduce the Risk of Colon Cancer Local-Regional Recurrence: Nationwide Population-Based Study From Danish Colorectal Cancer Group Database

BACKGROUND

It is controversial whether extensive resection of right-sided colon cancer confers oncological benefits.

OBJECTIVE

The aim of this study was to evaluate short- and long-term outcomes of extended surgical removal of the mesocolon compared to the conventional approach.

DESIGN

This was a retrospective population-based study.

SETTING

Study is based on a prospectively maintained Danish Colorectal Cancer Group database.

MAIN OUTCOME MEASURES

Primary outcome measures included local-regional recurrence in patients who underwent curative resection for right-sided colon cancer and 30-day postoperative complications. Distant metastasis, unplanned intraoperative adverse events, and 30- and 90-day postoperative mortality were also investigated. Patients who had palliative or compromised resection, emergency surgery, or neoadjuvant chemotherapy were excluded.

RESULTS

Of the 12,855 patients with resection of right-sided colon cancer retrieved, 1151 underwent extended right hemicolectomy. Patients who had extended right hemicolectomy were younger males with lower ASA scores, were operated on by colorectal surgeons using a laparoscopic approach, and had a significantly higher number of harvested lymph nodes. The rate of local-regional recurrence was 1.1% (136/12,855), with no difference between conventional right hemicolectomy and extended right hemicolectomy (OR, 1.7; 95% CI, 0.63-2.18). Postoperative medical complications were significantly higher in extended right hemicolectomy even after adjusting for age, comorbidity, access to the abdomen, and other covariates (OR, 1.26; 95% CI, 1.01-1.58). No significant difference was noticed between conventional right hemicolectomy and extended right hemicolectomy in the rates of distant metastasis, unplanned intraoperative adverse events, and mortality.

LIMITATIONS

Because it is a register-based study, underreporting cannot be excluded. Extended right hemicolectomy, as defined in this study, does not reflect the extent of lymphatic dissection performed during the surgery.

CONCLUSIONS

This large population-based register study showed no difference in local-regional recurrence of right-sided colon cancer between conventional and extended right hemicolectomy with mesenteric resection and ligation of the middle colic vessels. Extended resection was associated with higher rates of postoperative complications. See Video Abstract at http://links.lww.com/DCR/B907 .

LA RESECCIN AMPLIADA DEL COLON DERECHO NO REDUCE EL RIESGO DE RECURRENCIA LOCALREGIONAL DEL CNCER DE COLON ESTUDIO POBLACIONAL A NIVEL NACIONAL DE LA BASE DE DATOS DEL GRUPO DANS DE CNCER COLORRECTAL

ANTECEDENTES:Es aun un tema controversial si la resección ampliada del cáncer de colon del lado derecho confiere beneficios oncológicos.OBJETIVOS:El objetivo de este estudio fue examinar los resultados a corto y largo plazo de la resección quirúrgica ampliada del mesocolon en comparación con el enfoque convencional.DISEÑO:Este fue un estudio poblacional de tipo retrospectivo basado en una base de datos del Grupo Danés de Cáncer Colorrectal mantenida de manera prospectiva.AJUSTES:La medida de resultado primaria fue la recurrencia local-regional en pacientes sometidos a resección curativa por cáncer de colon del lado derecho y las medidas de resultado secundarias fueron las complicaciones posoperatorias a los 30 días. También fueron investigadas las metástasis a distancia, los eventos adversos intraoperatorios no planificados y la mortalidad posoperatoria a los 30 y 90 días. Se excluyeron los pacientes sometidos a resección paliativa o comprometida, cirugía de urgencia y quimioterapia neoadyuvante.RESULTADOS:De los 12.855 pacientes recuperados y sometidos a resección de cáncer de colon del lado derecho, 1151 fueron sometidos a hemicolectomía derecha ampliada. Los pacientes sometidos a hemicolectomía derecha ampliada fueron varones más jóvenes con puntuaciones ASA más bajas, operados por cirujanos colorrectales, utilizando la vía laparoscópica, y tuvieron un número significativamente mayor de ganglios linfáticos extraídos. La tasa de recidiva local-regional fue del 1,1% (136 / 12.855) sin diferencia entre la hemicolectomía derecha convencional y la hemicolectomía derecha ampliada (OR 1,7 IC 95% 0,63-2,18). Las complicaciones médicas post operatorias fueron significativamente mayores en la hemicolectomía derecha ampliada incluso después del ajuste por edad, comorbilidad, acceso al abdomen y otras covariables (OR 1,26; IC 95% 1,01-1,58). No se observaron diferencias significativas entre la hemicolectomía derecha convencional y la hemicolectomía derecha ampliada con respecto a las tasas de metástasis a distancia, eventos adversos intraoperatorios no planificados y mortalidad.LIMITACIONES:Es un estudio basado en registros, por lo tanto, no se puede excluir la sub notificación. La hemicolectomía derecha ampliada como se define en este estudio no refleja la extensión de la disección linfática realizada durante la cirugía.CONCLUSIONES:Este gran estudio basado en el registro poblacional no mostró diferencias en la recurrencia local-regional del cáncer de colon del lado derecho entre la hemicolectomía derecha convencional y ampliada con resección mesentérica y ligadura de los vasos cólicos medios. La resección ampliada se asoció con tasas más altas de complicaciones posoperatorias. Consulte Video Resumen en http://links.lww.com/DCR/B907 . (Traducción-Dr. Osvaldo Gauto ).

Simultaneous, Multi-Channel, Near-Infrared Fluorescence Visualization of Mesenteric Lymph Nodes Using Indocyanine Green and Methylene Blue: A Demonstration in a Porcine Model

Near-infrared fluorescence (NIRF) image-guided surgery is a useful tool that can help reduce perioperative complications and improve tissue recognition. Indocyanine green (ICG) dye is the most frequently used in clinical studies. ICG NIRF imaging has been used for lymph node identification. However, there are still many challenges in lymph node identification by ICG. There is increasing evidence that methylene blue (MB), another clinically applicable fluorescent dye, can also be useful in the intraoperative fluorescence-guided identification of structures and tissues. We hypothesized that MB NIRF imaging could be used for lymph node identification. The aim of this study was to evaluate the feasibility of intraoperative lymph node fluorescence detection using intravenously (IV) administered MB and compare it to ICG via a camera that has two dedicated near-infrared (NIR) channels. Three pigs were used in this study. ICG (0.2 mg/kg) was administered via a peripheral venous catheter followed by immediate administration of MB (0.25 mg/kg). NIRF images were acquired as video recordings at different time points (every 10 min) over an hour using the QUEST SPECTRUM^® 3 system (Quest Medical Imaging, Middenmeer, The Netherlands), which has two dedicated NIR channels for simultaneous intraoperative fluorescence guidance. The 800 nm channel was used to capture ICG fluorescence and the 700 nm channel was used for MB. The target (lymph nodes and small bowel) and the background (vessels-free field of the mesentery) were highlighted as the regions of interest (ROIs), and corresponding fluorescence intensities (FI) from these ROIs were measured. The target-to-background ratio (TBR) was then computed as the mean FI of the target minus the mean FI of the background divided by the mean FI of the background. In all included animals, a clear identification of lymph nodes was achieved at all time points. The mean TBR of ICG in lymph nodes and small bowel was 4.57 ± 1.00 and 4.37 ± 1.70, respectively for the overall experimental time. Regarding MB, the mean TBR in lymph nodes and small bowel was 4.60 ± 0.92 and 3.27 ± 0.62, respectively. The Mann-Whitney U test of the lymph node TBR/small bowel TBR showed that the TBR ratio of MB was statistically significantly higher than ICG. The fluorescence optical imaging technology used allows for double-wavelength assessment. This feasibility study proves that lymph nodes can be discriminated using two different fluorophores (MB and ICG) with different wavelengths. The results suggest that MB has a promising potential to be used to detect lymphatic tissue during image-guided surgery. Further preclinical trials are needed before clinical translation.

Definition and reporting of lymphadenectomy and complete mesocolic excision for radical right colectomy: a systematic review

BACKGROUND

Several procedures have been proposed to reduce the rates of recurrence in patients with right-sided colon cancer. Different procedures for a radical right colectomy (RRC), including extended D3 lymphadenectomy, complete mesocolic excision and central vascular ligation have been associated with survival benefits by some authors, but results are inconsistent. The aim of this study was to assess the variability in definition and reporting of RRC, which might be responsible for significant differences in outcome evaluation.

METHODS

PRISMA-compliant systematic literature review to identify the definitions of RRC. Primary aims were to identify surgical steps and different nomenclature for RRC. Secondary aims were description of heterogeneity and overlap among different RRC techniques.

RESULTS

Ninety-nine articles satisfied inclusion criteria. Eight surgical steps were identified and recorded as specific to RRC: Central arterial ligation was described in 100% of the included studies; preservation of mesocolic integrity in 73% and dissection along the SMV plane in 67%. Other surgical steps were inconstantly reported. Six differently named techniques for RRC have been identified. There were 35 definitions for the 6 techniques and 40% of these were used to identify more than one technique.

CONCLUSIONS

The only universally adopted surgical step for RRC is central arterial ligation. There is great heterogeneity and consistent overlap among definitions of all RRC techniques. This is likely to jeopardise the interpretation of the outcomes of studies on the topic. Consistent use of definitions and reporting of procedures are needed to obtain reliable conclusions in future trials. PROSPERO CRD42021241650.

Complete mesocolic excision for right colonic cancer: prospective multicentre study

BACKGROUND

Complete mesocolic excision (CME) for right colonic cancer is a more complex operation than standard right hemicolectomy but evidence to support its routine use is still limited. This prospective multicentre study evaluated the effect of CME on long-term survival in colorectal cancer centres in Germany (RESECTAT trial). The primary hypothesis was that 5-year disease-free survival would be higher after CME than non-CME surgery. A secondary hypothesis was that there would be improved survival of patients with a mesenteric area greater than 15 000 mm2.

METHODS

Centres were asked to continue their current surgical practices. The surgery was classified as CME if the superior mesenteric vein was dissected; otherwise it was assumed that no CME had been performed. All specimens were shipped to one institution for pathological analysis and documentation. Clinical data were recorded in an established registry for quality assurance. The primary endpoint was 5-year overall survival for stages I-III. Multivariable adjustment for group allocation was planned. Using a primary hypothesis of an increase in disease-free survival from 60 to 70 per cent, a sample size of 662 patients was calculated with a 50 per cent anticipated drop-out rate.

RESULTS

A total of 1004 patients from 53 centres were recruited for the final analysis (496 CME, 508 no CME). Most operations (88.4 per cent) were done by an open approach. Anastomotic leak occurred in 3.4 per cent in the CME and 1.8 per cent in the non-CME group. There were slightly more lymph nodes found in CME than non-CME specimens (mean 55.6 and 50.4 respectively). Positive central mesenteric nodes were detected more in non-CME than CME specimens (5.9 versus 4.0 per cent). One-fifth of patients had died at the time of study with recorded recurrences (63, 6.3 per cent), too few to calculate disease-free survival (the original primary outcome), so overall survival (not disease-specific) results are presented. Short-term and overall survival were similar in the CME and non-CME groups. Adjusted Cox regression indicated a possible benefit for overall survival with CME in stage III disease (HR 0.52, 95 per cent c.i. 0.31 to 0.85; P = 0.010) but less so for disease-free survival (HR 0.66; P = 0.068). The secondary outcome (15 000 mm2 mesenteric size) did not influence survival at any stage (removal of more mesentery did not alter survival).

CONCLUSION

No general benefit of CME could be established. The observation of better overall survival in stage III on unplanned exploratory analysis is of uncertain significance.

Laparoscopic extended right hemicolectomy versus laparoscopic transverse colectomy for mid-transverse colon cancer: a multicenter retrospective study from Kanagawa Yokohama Colorectal Cancer (KYCC) study group

PURPOSE

The laparoscopic surgery approach for mid-transverse colon cancer (MTC) varies depending on tumor characteristics and the guidelines implemented by each surgeon; the optimal surgical procedure for MTC has not been established. This study aimed to compare the surgical outcomes of laparoscopic extended right hemicolectomy (Lap-ERHC) and laparoscopic transverse colectomy (Lap-TC) for MTC.

METHODS

This was a multicenter, retrospective study. We surveyed eight hospitals, by questionnaire, on MTC surgery policies and retrospectively compared the short- and long-term surgical outcomes for patients with MTC who underwent Lap-ERHC or Lap-TC between January 2008 and December 2019.

RESULTS

A total of 129 patients were enrolled, of whom 35 underwent Lap-ERHC and 94 underwent Lap-TC. There were no significant differences in tumor progression between the two groups. Operation time was significantly longer (202 min vs. 185 min, p = 0.026). We observed a higher complication rate (≥ grade 3) in the Lap-ERHC group than in the Lap-TC group (11.4% vs. 3.2%, p = 0.086). Three patients (8.6%) who underwent Lap-ERHC developed anastomotic leakage; none of the patients who underwent Lap-TC had this complication (p = 0.018). The 3-year overall survival rates (stage I: 100% vs. 91.9%, p = 0.64; stage II: 100% vs. 95.5%, p = 0.46; stage III: 100% vs. 88.2%, p = 0.91, respectively) were similar between the two groups.

CONCLUSION

Lap-ERHC for MTC has the same long-term outcomes as Lap-TC. However, Lap-ERHC for MTC has a higher complication rate. Therefore, Lap-TC may be recommended for patients with MTC.

TRIAL REGISTRATION

UMIN000042674.

D3 Versus D2 Lymphadenectomy in Right Hemicolectomy: A Systematic Review and Meta-analysis

PURPOSE

D3 lymphadenectomy for right colon cancer improves oncological outcomes. This meta-analysis aimed to compare operation data, histopathological characteristics, perioperative conditions, and long-term survival after D3 and D2 lymphadenectomy in right hemicolectomy.

METHODS

We searched PubMed, Embase, and the Cochrane Library for relevant articles (up to March 31, 2020). Random-effects and fixed-effects meta-analysis models were used. Review Manager (RevMan) version 5.3 and Stata version 15.1 were used for pooled estimates.

RESULTS

After screening 714 articles, 7 articles with a total of 1368 patients were eligible for inclusion. Compared with D2, D3 lymphadenectomy improves results in terms of blood loss (weighted mean difference [WMD] = -20.63, 95% confidence interval [CI] -28.19 to -13.16, P < .01), harvested lymph nodes (WMD = 8.86, 95% CI 7.74 to 9.98, P < .01), 3-year overall survival (OS) (hazard ratio [HR] = 2.03, 95% CI 1.20 to 3.43, P < .01), 5-year OS (HR = 2.22, 95% CI 1.15 to 4.30, P = .02), and 5-year disease-free survival (DFS) (HR = 2.16, 95% CI 1.19 to 3.90, P = .01). There was no significant difference regarding operation time, anastomosis leakage, wound infection, overall morbidity, postoperative hospital stay, mortality, length of dissected colon, and 3-year DFS (P >= .05).

CONCLUSIONS

It is suggested in this review that D3 lymphadenectomy is superior to D2 lymphadenectomy in terms of blood loss, harvested lymph nodes, 3-year OS, 5-year OS, and 5-year DFS. The conclusion must be drawn with caution due to the limited number of included studies. Further RCTs are needed for stronger evidence.

Primary tumour immune response and lymph node yields in colon cancer

Background

The mechanism underlying improved survival in non-metastatic colon cancer with higher lymph node (LN) yield is unknown. This study aimed to identify whether molecular features in the primary tumour were predictive of LN yield.

Methods

Clinical, genomic, transcriptomic, proteomic and methylation data of non-metastatic, colon cancers studied in The Cancer Genome Atlas were interrogated for associations with LN yield. Based on maximal survival effects, patients were segregated into high (>15) and low (≤15) LN yield. Gene set enrichment analysis was performed on transcriptomic changes to identify biological processes associated with LN yield. Correlations were validated in an independent set of Stage II colon cancers.

Results

High LN yield was found predictive of overall and disease-free survival. There was no association of higher LN yield and increasing nodal positivity. High LN yield was strongly linked with gene expression changes associated with the adaptive and dendritic cell immune response. This association was most prominent in node-negative cancers. Analogous findings were reproduced in the validation dataset.

Conclusion

The study shows a strong association of an activated immune response in tumours with a high LN yield. Immunogenic tumours have a better prognosis, likely explaining the survival benefit with higher LN yields.

Complete mesocolic excision versus conventional surgery for colon cancer: A systematic review and meta-analysis

AIM

Complete mesocolic excision (CME) lacks consistent data advocating operative superiority compared to conventional surgery for colon cancer. We performed a systematic review and meta-analysis, analysing population characteristics and perioperative, pathological and oncological outcomes.

METHODS

D3 extended lymphadenectomy dissection was considered comparable to CME, and D2 and D1 dissection to be comparable to conventional surgery. Outcomes reviewed included lymph node yield, R1 resection, overall complications, overall survival and disease-free survival.

RESULTS

In all, 3039 citations were identified; 148 studies underwent full-text reviews and 31 matched inclusion criteria: total cohort 26 640 patients (13 830 CME/D3 vs. 12 810 conventional). Overall 3- and 5-year survival was higher in the CME/D3 group compared with conventional surgery: relative risk (RR) 0.69 (95% CI 0.51-0.93, P = 0.016) and RR 0.78 (95% CI 0.64-0.95, P = 0.011) respectively. Five-year disease-free survival also demonstrated CME/D3 superiority (RR 0.67, 95% CI 0.52-0.86, P < 0.001), with similar findings at 1 and 3 years. There were no statistically significant differences between the CME/D3 and conventional group in overall complications (RR 1.06, 95% CI 0.97-1.14, P = 0.483) or anastomotic leak (RR 1.02, 95% CI 0.81-1.29, P = 0.647).

CONCLUSIONS

Meta-analysis suggests CME/D3 may have a better overall and disease-free survival compared to conventional surgery, with no difference in perioperative complications. Quality of evidence regarding survival is low, and randomized control trials are required to strengthen the evidence base.

Right hemicolectomy with complete mesocolic excision is safe, leads to an increased lymph node yield and to increased survival: results of a systematic review and meta-analysis

BACKGROUND

The introduction of complete mesocolic excision (CME) for right colon cancer has raised an important discussion in relation to the extent of colic and mesenteric resection, and the impact this may have on lymph node yield. As uncertainty remains regarding the usefulness of and indications for right hemicolectomy with CME and the benefits of CME compared with a traditional approach, the purpose of this meta-analysis is to compare the two procedures in terms of safety, lymph node yield and oncological outcome.

METHODS

We performed a systematic review of the literature from 2009 up to March 15th, 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two hundred eighty-one publications were evaluated, and 17 met the inclusion criteria and were included. Primary endpoints analysed were anastomotic leak rate, blood loss, number of harvested lymph nodes, 3- and 5-year oncologic outcomes. Secondary outcomes were operating time, conversion, intraoperative complications, reoperation rate, overall and Clavien-Dindo grade 3-4 postoperative complications.

RESULTS

In terms of safety, right hemicolectomy with CME is not inferior to the standard procedure when comparing rates of anastomotic leak (RR 0.82, 95% CI 0.38-1.79), blood loss (MD -32.48, 95% CI -98.54 to -33.58), overall postoperative complications (RR 0.82, 95% CI 0.67-1.00), Clavien-Dindo grade III-IV postoperative complications (RR 1.36, 95% CI 0.82-2.28) and reoperation rate (RR 0.65, 95% CI 0.26-1.75). Traditional surgery is associated with a shorter operating time (MD 16.43, 95% CI 4.27-28.60) and lower conversion from laparoscopic to open approach (RR 1.72, 95% CI 1.00-2.96). In terms of oncologic outcomes, right hemicolectomy with CME leads to a higher lymph node yield than traditional surgery (MD 7.05, 95% CI 4.06-10.04). Results of statistical analysis comparing 3-year overall survival and 5-year disease-free survival were better in the CME group, RR 0.42, 95% CI 0.27-0.66 and RR 0.36, 95% CI 0.17-0.56, respectively.

CONCLUSIONS

Right hemicolectomy with CME is not inferior to traditional surgery in terms of safety and has a greater lymph node yield when compared with traditional surgery. Moreover, right-sided CME is associated with better overall and disease-free survival.

Complete Mesocolic Excision and D3 Lymphadenectomy versus Conventional Colectomy for Colon Cancer: A Systematic Review and Meta-Analysis

BACKGROUNDS

Previous systematic reviews suggest that the implementation of 'complete mesocolon excision' (CME) for colon tumors entails better specimen quality but with limited long-term outcomes. We performed a meta-analysis to compare the pathological, perioperative, and oncological results of CME with conventional surgery (CS) in primary colon cancer.

METHODS

Embase, MEDLINE and CENTRAL databases were searched using Medical Subject Headings for CME and D3 lymphadenectomy. The systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 18,989 patients from 27 studies were included. Postoperative complications were higher in the CME group (relative risk [RR] 1.13, 95% confidence interval [CI] 1.04-1.22, I² = 0%), while no differences were observed in terms of anastomotic leak (I² = 0%) or perioperative mortality (I² = 49%). CME was associated with a higher number of lymph nodes harvested (I² = 95%), distance to high tie (I² = 65%), bowel length (I² = 0%), and mesentery area (I² = 95%). CME also had positive effects on 3- and 5-year overall survival (RR 1.09, 95% CI 1.04-1.15, I² = 88%; and RR 1.05, 95% CI 1.02-1.08, I² = 62%, respectively) and 3-year disease-free survival (RR 1.10, 95% CI 1.04-1.17, I² = 22%), as well as decreased local (RR 0.35, 95% CI 0.24-0.51, I² = 51%) and distant recurrences (RR 0.71, 95% CI 0.60-0.85, I² = 34%).

CONCLUSIONS

Limited evidence suggests that CME improves oncological outcomes with a higher postoperative adverse events rate but no increase in anastomotic leak rate or perioperative mortality, compared with CS.

Surgical Approach to Transverse Colon Cancer: Analysis of Current Practice and Oncological Outcomes Using the National Cancer Database

BACKGROUND

Surgical treatment for transverse colon cancer involves either extended colectomy or segmental resection, depending on the location of the tumor and surgeon perspective. However, the oncological safety of segmental resection has not yet been established in large cohort studies.

OBJECTIVE

This study aims to compare segmental resection versus extended colectomy for transverse colon cancer in terms of oncological outcomes.

DESIGN

This was a retrospective cohort study.

SETTINGS

This study was conducted using a nationwide cohort.

PATIENTS

A total of 66,062 patients who underwent colectomy with curative intent for transverse stage I to III adenocarcinoma were identified in the National Cancer Database (2004-2015).

MAIN OUTCOME MEASURES

Patients were divided in 2 groups based on the type of surgery received (extended versus segmental resection). The primary outcome was overall survival. Secondary outcomes were 30- and 90-day mortality, length of hospital stay, and readmission rate within 30 days of surgical discharge.

RESULTS

Extended colectomy was performed in 44,417 (67.2%) patients, whereas 21,645 (32.8%) patients underwent segmental resection. Extended colectomy was associated with lower survival at multivariate analysis (HR, 1.07; 95% CI, 1.04-1.10; p < 0.001). The subgroup analysis showed that extended resection was independently associated with poorer survival in mid transverse colon cancers (HR, 1.08; 95% CI, 1.04-1.12; p < 0.001) and in stage III tumors (HR, 1.11; 95% CI, 1.04-1.18; p < 0.001). The number of at least 12 harvested lymph nodes was an independent predictor of improved survival in both overall and subgroup analyses.

LIMITATIONS

This study was limited by its retrospective design.

CONCLUSION

Extended colectomy was not associated with a survival advantage compared with segmental resection. On the contrary, extended colectomy was associated with slightly poorer survival in mid transverse cancers and locally advanced tumors. Segmental resection was found to be safe when appropriate margins and adequate lymph node harvest were achieved. See Video Abstract at http://links.lww.com/DCR/B454.

ABORDAJE QUIRRGICO DEL CNCER DE COLON TRANSVERSO ANLISIS DE LA PRCTICA ACTUAL Y LOS RESULTADOS ONCOLGICOS UTILIZANDO LA BASE DE DATOS NACIONAL DE CNCER

ANTECEDENTES:El tratamiento quirúrgico para el cáncer de colon transverso implica colectomía extendida o resección segmentaria, según la ubicación del tumor y la perspectiva del cirujano. Sin embargo, la seguridad oncológica de la resección segmentaria aún no se ha establecido en estudios de cohortes grandes.OBJETIVO:Este estudio tiene como objetivo comparar la resección segmentaria versus la colectomía extendida para el cáncer de colon transverso en términos de resultados oncológicos.DISEÑO:Este fue un estudio de cohorte retrospectivo.ESCENARIO:Este estudio se realizó utilizando una cohorte a nivel nacional.PACIENTES:Un total de 66,062 pacientes que se sometieron a colectomía con intención curativa por adenocarcinoma de colon transverso en estadio I-III fueron identificados en la Base de Datos Nacional del Cáncer (2004-2015).PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes se dividieron en dos grupos según el tipo de cirugía recibida (resección extendida versus resección segmentaria). El resultado primario fue la supervivencia global. Los resultados secundarios fueron la mortalidad a los 30 y 90 días, la duración de la estancia hospitalaria y la tasa de reingreso dentro de los 30 días posteriores al alta quirúrgica.RESULTADOS:Se realizó colectomía extendida en 44,417 (67.2%) casos, mientras que 21,645 (32.8%) pacientes fueron sometidos a resección segmentaria. La colectomía extendida se asoció con una menor supervivencia en el análisis multivariado (HR 1.07 IC 95% 1.04-1.10; p <0.001). El análisis de subgrupos mostró que la resección extendida se asoció de forma independiente con una menor supervivencia en los cánceres de colon transverso medio (HR 1.08 IC 95% 1.04-1.12; p <0.001) y en tumores en estadio III (HR 1.11 IC 95% 1.04-1.18; p <0.001). Un número de al menos 12 ganglios linfáticos cosechados fue un predictor independiente de una mejor supervivencia en los análisis general y de subgrupos.LIMITACIONES:Este estudio estuvo limitado por su diseño retrospectivo.CONCLUSIÓN:La colectomía extendida no se asoció con una ventaja de supervivencia en comparación con la resección segmentaria. Por el contrario, la colectomía extendida se asoció con una supervivencia levemente menor en cánceres de colon transverso medio y tumores localmente avanzados. Se encontró que la resección segmentaria es segura cuando se logran los márgenes apropiados y la cosecha adecuada de ganglios linfáticos. Consulte Video Resumen en http://links.lww.com/DCR/B454.

D3-lymphadenectomy enhances oncological clearance in patients with right colon cancer. Results of a meta-analysis

BACKGROUND

D3-Lymphadenectomy, together with complete mesocolic excision (CME), were introduced to provide oncological results after right colon cancer. The aim of this systematic review with meta-analysis was to assess the short and long-term outcomes of right-sided hemicolectomy with CME + D3 as compared with classic right hemicolectomy. Secondary aims included the prevalence of D3-metastasis and skip metastasis when performing CME + D3.

MATERIAL AND METHODS

A systematic review with meta-analysis was conducted, according to PRISMA methodology.

RESULTS

29 studies were enrolled (2592 patients). No differences were accounted in morbidity variables associated with the measured techniques. CME + D3 was significantly associated with a greater distance between the tumour and the closest vascular tie, a longer colonic resection, a wider resection of mesentery and an increased number of harvested lymph nodes. Regarding to long-terms outcomes, we found a significant decrease in local recurrence in patients undergoing CME + D3 (HR:0.17) and a significant improvement in 3-year and 5-year overall survival rates (HR:0.53 vs. HR:0.57, respectively), as well as an improving survival in patients with stage II and III disease. Overall prevalence of patients with lymphatic metastases in D3-territory was of 8.6% and 2.2% of skip metastases.

CONCLUSIONS

CME + D3 is a feasible surgical procedure that allows to obtain specimens with higher quality oncological resection, without greater associated morbidity, thus improving survival in patients with stage II and III right colon cancer.

Metastasis to lymph nodes around the vascular tie worsens long-term oncological outcomes following complete mesocolic excision and conventional colectomy for right-sided colon cancer

BACKGROUND

Oncologic outcomes after complete mesocolic excision (CME) in colon cancer are under investigation. The aim of our study was to compare CME and conventional colectomy (CC) in terms of pathological and oncological outcomes for right colon cancer and to evaluate the impact of lymph node metastasis around the vascular tie on survival.

METHODS

Consecutive patients with right colon cancer who had CME or CC between January 2011 and August 2018 at two specialized centers in Turkey were included. Statistical analyses were performed with respect to demographic characteristics, operative and pathologic outcomes, harvested and metastatic lymph nodes around the vascular tie (LNVT), recurrences, and survival.

RESULTS

There were 91 patients in the CME group (58 males, mean age 64 ± 16 years) and 192 patients in the CC group (96 males, mean age 66 ± 14 years). The mean number of harvested lymph nodes (CME: 42 ± 15 vs CC: 34 ± 13, p = 0.01) and LNVT were higher in the CME group (CME: 3.2 ± 2.2 vs CC: 2.4 ± 1.6, p = 0.001). LNVT metastases were 7.7% and 8.3% in the CME and CC groups, respectively (p = 0.85). Three-year overall and disease-free survival rates were 96.4% and 90.9% in the CME group and 90.4% and 87.6% in the CC group in stage I-III patients (p > 0.05). In stage III patients, the 3-year overall survival (92.5% vs 63.5%, p = 0.03) and disease-free survival (85.6% vs 52.1%, p = 0.008) were significantly better in LNVT-negative patients than in LNVT-positive patients.

CONCLUSION

LNVT metastasis seems to be the key factor associated with poor disease-free and overall survival in right colon cancer regardless of the radicality of surgery.

Laparoscopic Complete Mesocolic Excision for Right-Sided Colon Cancer: Analysis of Feasibility and Safety from a Single Western Center

BACKGROUND

Colectomies performed according to complete mesocolic excision (CME) principles have demonstrated an improvement in the quality of surgical specimen and a potential improvement of long-term results. Laparoscopic CME right hemicolectomy is considered a demanding procedure and adopted in few centers from the West. The main purpose of this paper is to present a video showing our technique for laparoscopic CME right hemicolectomy and to analyze our short-term results to prove its safety.

METHODS

Data from 38 patients operated on at the Division of General and Hepatobiliary Surgery, University of Verona Hospital Trust, between September 2014 and February 2017, were included in the study.

RESULTS

In the present series, 37% of patients were ≥75 years old, 32% of patients were ASA class 3, 46% of patients had ≥2 comorbidities, 30% of patients had BMI >28 and 17% of patients had ≥2 previous abdominal surgeries. Despite these unfavorable clinic characteristics, no mortality was observed, Clavien-Dindo ≥3 complications occurred in 13.1% and redo surgery in 5.3%. Good quality specimens were obtained with a mean (SD) length of 34.5±7.5 cm, a proximal margin of 16.8±9.2 cm and a distal margin of 14.3±6.4 cm. The mean (SD) number of harvested lymph nodes was 24.3 (8.3).

CONCLUSIONS

When implemented in a Western center, laparoscopic CME right hemicolectomy is feasible and safe and allows obtaining good quality specimens.

Comparison between conventional colectomy and complete mesocolic excision for colon cancer: a systematic review and pooled analysis : A review of CME versus conventional colectomies

BACKGROUND

Complete mesocolic excision (CME) is advocated based on oncologic superiority, but not commonly performed in North America. Many data are case series with few comparative studies. Our aim was to perform a systematic review comparing outcomes between CME and non-CME colectomy.

METHODS

A systematic review was performed according to PRISMA guidelines of MEDLINE, EMBASE, HealthStar, Web of Science, and Cochrane Library. Studies were included if they compared conventional resection (non-CME) to CME for colon cancer. Quality was assessed using methodological index for non-randomized studies (MINORS). The main outcome measures were short-term morbidity and oncologic outcomes. Weighted pooled means and proportions with 95% CI were calculated using a random-effects model when appropriate.

RESULTS

Out of 825 unique citations, 23 studies underwent full-text reviews and 14 met inclusion criteria. Mean MINORS score was 13.3 (range 11-15). The mean sample size in CME group was 1166 (range 45-3756) and 945 (range 40-3425) in non-CME. Four papers reported plane of dissection, with CME plane achieved in 85.8% (95% CI 79.8-91.7). Mean OR time in CME group was 167 min (163-171) and 138 min (135-142) in conventional group. Perioperative morbidity was reported in six studies, with pooled overall complications of 22.5% (95% CI 18.4-26.6) for CME and 19.6 (95% CI 13.6-25.5) for non-CME. Anastomotic leak occurred in 6.0% (95% CI 2.2-9.7) of CME resections versus 6.0% (95% CI 4.1-7.9) in non-CME. CME had more lymph nodes, longer distance to high tie, and specimen length in all studies. Nine studies compared long-term oncologic outcomes and only three reported statistically significant higher disease-free or overall survival in favor of CME. Local recurrence was lower after CME in two of four studies.

CONCLUSIONS

The quality of evidence is limited and does not consistently support the superiority of CME. Better data are needed before CME can be recommended as the standard of care for colon cancer resections.

Complete mesocolic excision in right-sided colon cancer does not increase severe short-term postoperative adverse events

AIM

The aim was to assess whether complete mesocolic excision (CME) in patients with right-sided colon cancer is related to short-term mortality or postoperative adverse events requiring reoperation. The complete mobilization of an integral mesocolon and central ligation of blood vessels are essential steps in CME surgery. The resultant specimen, with an intact mesocolic fascia and a high number of harvested lymph nodes, is believed to be oncologically favourable. However, it has been suggested that CME surgery may increase the risk of intra-operative severe adverse events, due to exposure of vital retroperitoneal organs and large blood vessels.

METHOD

In a population-based, nested case-control study, all residents in the Stockholm County operated for right-sided colon cancer from 2004 until 2012 were identified from the Swedish Colorectal Cancer Registry. Patients who died within 90 days after surgery or were reoperated within 30 days after surgery, or during the index hospital stay, were defined as cases. Two controls per case were randomly sampled and individually matched for age, sex, TNM stage and emergency vs elective surgery. Exposure status (CME surgery) was assessed from original surgical reports.

RESULTS

The estimated proportion of CME surgery was 14.8% (35 of 236) for cases and 19.5% (92 of 473) for controls. The unadjusted OR for short-term mortality or reoperation after CME surgery was 0.72 (95% CI: 0.47-1.10; P = 0.15). The ORs were lower in the late part of the study (0.51; 95% CI: 0.26-1.01) and in high volume hospitals (0.61, 95% CI: 0.35-1.06).

CONCLUSIONS

The present study does not indicate that CME surgery is associated with an increased risk of severe adverse events such as 90-day mortality or reoperation.

Using fluorescence lymphangiography to define the ileocolic mesentery: proof of concept for the watershed area using real-time imaging

Recent advances in mesenteric science have demonstrated that the mesentery is a continuous structure with a 'watershed' area at the mesenteric apex between the right colon and terminal ileum, where lymphatic flow can proceed either proximally or distally. With this new understanding of the anatomy, functional features are emerging, which can have an impact on surgical management. Fluorescence lymphangiography or lymphoscintigraphy with indocyanine green allows real-time visualization of lymphatic channels, which highlights sentinel lymph nodes and may facilitate identification of the ideal margins for mesenteric lymphadenectomy during bowel resection for colon cancer. By using this novel technology, it is possible to demonstrate a watershed area in the ileocolic region and may facilitate more precise mesenteric dissection. In the present study, we provide proof of concept for the ileocolic watershed area using fluorescence lymphangiography.

Safety of laparoscopic surgery for colorectal cancer in patients over 80 years old: a propensity score matching study

PURPOSES

To establish the safety of laparoscopic-assisted colorectal resection for colorectal cancer in elderly patients aged ≥80 years.

METHODS

Data were obtained from a chart review of patients who underwent colorectal cancer resection between 2009 and 2014 in Kochi Medical School. The effect of patient age on the extent of lymph node dissection and operative safety was assessed by comparing the short-term results of elderly patients with those of younger patients after propensity score matching.

RESULTS

Of a total of 506 patients with colorectal cancer, 398 underwent laparoscopic surgery and 23% of these patients were aged ≥80 years old. The elderly patients tended to have poorer general condition and larger tumors, although no significant differences were found in tumor invasion, lymph node metastasis, or synchronous distant metastasis between the groups. After adjustment for preoperative factors, we noted that the elderly patients tended to undergo less aggressive surgical resection (P = 0.01). Further analysis after including surgical factors for propensity score matching revealed a similar rate of complications in the two groups (24 vs. 25%, respectively; P = 0.85), and similar postoperative death rates and length of postoperative hospital stay.

CONCLUSION

The findings of the present study demonstrate that laparoscopic surgery for colorectal cancer should not be avoided based on simply the age of the patient.