Lower survival after right-sided versus left-sided colon cancers: Is an extended lymphadenectomy the answer?

Prognostic value of primary tumor location in colorectal cancer: an updated meta-analysis

The clinical, histological, and molecular differences between right-sided colon cancer (RCC) and left-sided colon cancer (RCC) have received considerable attention. Over the past decade, many articles have been published concerning the association between primary tumor location (PTL) of colorectal cancer and survival outcomes. Therefore, there is a growing need for an updated meta-analysis integrating the outcomes of recent studies to determine the prognostic role of right vs left-sidedness of PTL in patients with colorectal cancer. We conducted a comprehensive database review using PubMed, SCOPUS, and Cochrane library databases from February 2016 to March 2023 for prospective or retrospective studies reporting data on overall survival (OS) and cancer-specific survival (CSS) of RCC compared with LCC. A total of 60 cohort studies comprising 1,494,445 patients were included in the meta-analysis. We demonstrated that RCC is associated with a significantly increased risk of death compared with LCC by 25% (hazard ratio (HR), 1.25; 95% confidence interval (CI), 1.19-1.31; I2 = 78.4%; Z = 43.68). Results showed that patients with RCC have a worse OS compared with LCC only in advanced stages (Stage III: HR, 1.275; 95% CI 1.16-1.4; P = 0.0002; I2 = 85.8%; Stage IV: HR, 1.34; 95% CI 1.25-1.44; P < 0.0001; I2 = 69.2%) but not in primary stages (Stage I/II: HR, 1.275; 95% CI 1.16-1.4; P = 0.0002; I2 = 85.8%). Moreover, a meta-analysis of 13 studies including 812,644 patients revealed that there is no significant difference in CSS between RCC and LCC (HR, 1.121; 95% CI 0.97-1.3; P = 0.112). Findings from the present meta-analysis highlight the importance of PTL in clinical decision-making for patients with CRC, especially in advanced stages. We provide further evidence supporting the hypothesis that RCC and LCC are distinct disease entities that should be managed differently.

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.

Survival rate of colorectal cancer in China: A systematic review and meta-analysis

Background

This study aims to comprehensively summarize the colorectal survival rate in China. Method: In PubMed and Web of Science, keywords such as "colorectal cancer", "survival" and "China" were used to search literatures in the past 10 years. Random effect models were selected to summarize 1-year, 3-year, and 5-year survival rates, and meta-regression and subgroup analyses were performed on the included studies.

Results

A total of 16 retrospective and prospective studies providing survival rates for colorectal cancer in China were included. The 1-year, 3-year, and 5-year survival rates of colorectal cancer in China were 0.79, 0.72 and 0.62, respectively. In the included studies, the 5-year survival rates of stage I (5474 cases), stage II (9215 cases), stage III (8048 cases), and stage IV (4199 cases) colorectal cancer patients were 0.85, 0.81, 0.57 and 0.30, respectively. Among them, the 5-year survival rates of colorectal cancer were 0.82, 0.76, 0.71, 0.67, 0.66, 0.65 and 0.63 in Tianjin, Beijing, Guangdong, Shandong, Liaoning, Zhejiang and Shanghai, respectively.

Conclusion

The 5-year survival rate in China is close to that of most European countries, but still lower than Japan and South Korea, and the gap is gradually narrowing. Region, stage, differentiation, pathological type, and surgical approach can affect 5-year survival in colorectal cancer.

Systematic review registration

https://www.crd.york.ac.uk/prospero/ identifier, CRD42022357789.

Integrated Decision-Making in the Treatment of Colon-Rectal Cancer: The Case of KRAS-Mutated Tumors

In recent years, precision medicine has taken an increasing place in various branches of medical oncology, including colorectal cancer. Among the potentially relevant mutations for this cancer is the KRAS mutation, initially defined as "untargetable"; today, we see the birth of new molecules that target one of the variants of the KRAS mutation, KRAS G12C, having a significant impact on the therapeutic options for other malignancies, such as metastatic lung cancer. This fundamental step forward has stimulated scientific research on other potential targets of KRAS, both indirect and direct, and combination treatments aiming to overcome the mechanisms of resistance to these drugs that decrease in efficacy in colorectal cancer. What was once a negative predictive marker of response to anti-EGFR drugs today has become a potential target for targeted treatments. In turn, the prognostic role of the mutation has become extremely interesting, making it a potentially useful element in therapeutic decision-making, not only regarding oncological treatments but also in a more complex and complete manner within a global vision of the patient, involving other figures on the multidisciplinary team, such as surgeons, radiotherapists, and interventional radiologists.

Do differences in surgical quality account for the higher rate of R1 margins to lymph node metastases in right- versus left-sided Stage III colon cancer: A retrospective cohort study

AIM

Microscopically positive (R1) margins to lymph node metastases (R1LNM) are associated with poorer oncological outcomes in patients with Stage III colon cancer. R1LNM margins are more common in right-sided cancer, although the cause of this phenomenon is unknown. We sought to investigate whether differences in surgical quality account for the higher rate of R1LNM in right-sided cancers.

METHOD

Patients treated for Stage III colon cancer from 1 January 2016 to 31 December 2018 were identified using the Danish national cancer registry. Indicators of surgical quality (mesocolic resection grade, median lymph node yield, and length to the distal colonic margin) were compared according to tumour site and margin status.

RESULTS

In all, 1765 patients were included, 981 (55.6%) with right-sided cancers. R1LNM margins were more common in right-sided cancers (14.4% vs. 6.1%, P < 0.001). All three surgical quality indicators were higher in patients with right-sided cancers (mesocolic resection planes 81.7% vs. 69.5%, P < 0.001; median lymph node yield 28 vs. 25, P < 0.001; ≥5 cm to the distal colon margin 81.2% vs. 53.6%, P < 0.001). When stratified according to margin status, no differences in mesocolic resection planes or resectate length were noted, whilst median lymph node yield was higher in patients with R1LNM margins (29 vs. 27, P = 0.009).

CONCLUSION

Surgical quality does not appear to be poorer in patients undergoing surgery for right-sided versus left-sided colon cancers in Denmark. Suboptimal surgery does not appear to be responsible for R1LNM margins, implying that these margins may be a surrogate for more aggressive biology.

Is increasing nodal count associated with improved recurrence-free and overall survival following standard right hemicolectomy for colon cancer?

BACKGROUND AND OBJECTIVES

Increasing lymph node harvest for right-sided colon cancer is associated with improved overall survival (OS), but most relevant studies failed to report the extent of resection. We examined the association between increasing lymph node count with standard right hemicolectomy according to nodal status and prognostic outcomes in right-sided tumors.

METHODS

Retrospective analysis of prospectively collected clinical data from patients with proximal colonic adenocarcinomas (n = 1390) following right hemicolectomy. Associations between lymph node counts (0-12 vs. 13-15, 16-20, and >20) and recurrence-free survival (RFS) and OS were examined using multivariate Cox modeling adjusted for confounders.

RESULTS

We found no association between increasing nodal count and RFS, regardless of nodal status. In the absence of nodal metastases, increasing nodal count (16-20 and >20 vs. 0-12 nodes) was associated with 57% (95% confidence interval [CI]: 0.21-0.89) and 52% (95% CI: 0.24-0.95) improved OS, respectively. In the presence of nodal metastases, increasing nodal count was not associated with OS. Adjuvant chemotherapy did not modify this effect.

CONCLUSION

Increasing nodal count (>15 nodes) with right hemicolectomy was not associated with improved RFS. Improved OS was only found for node-negative tumors, casting some doubt on the benefits of resecting more lymph nodes in the presence of nodal metastases.

Propensity-score-matched analysis of D2 and D3 right hemicolectomy for colon cancer

BACKGROUND

Complete mesocolic excision with D3 lymph node dissection in right-sided colon cancer is associated with improved oncological outcomes, but can potentially be associated with higher rates of complications compared to conventional D2 right hemicolectomy. This study aims to evaluate the oncological and perioperative outcomes of patients who underwent D3 right hemicolectomy, comparing to conventional right hemicolectomy.

METHODS

From 2015 to 2020, 360 patients underwent right hemicolectomy for colonic malignancies. Data was retrospectively analysed from a prospectively collected database. A propensity-score-matched analysis was performed between the two groups to evaluate their outcomes.

RESULTS

About 88(24.4%) patients underwent D3 right hemicolectomy, with the rest undergoing D2 right hemicolectomy. After propensity-matched analysis, D3 right hemicolectomy had a higher lymph node yield (median of 26 versus 23, p = 0.005), lower overall recurrence rate (11.7% versus 25.7%, p = 0.03), and lower overall mortality rate (14.5% versus 30.1%, p = 0.02) There were no significant differences in the complication rates. There were no anastomotic leaks. D3 right hemicolectomy was associated with an improved 3-year disease-free survival (DFS) with a hazard ratio of 0.63 (P = 0.21), and also an improved 3-year overall survival (OS) with a hazard ratio of 0.68 (P = 0.31).

CONCLUSION

D3 right hemicolectomy is associated with a higher lymph node yield, without increasing morbidity or mortality. It is also associated with significantly lower recurrence and overall mortality rates in this study. Short term 3-year DFS and OS also trend towards favouring D3 right hemicolectomy. However, this study is limited by the small sample size and retrospective nature.

Lymph node yield in the pathological staging of resected nonmetastatic colon cancer: The more the better?

INTRODUCTION

Guidelines recommend regional lymphadenectomy with a lymph node yield (LNY) of at least 12 lymph nodes (LN) for adequate colon cancer (CC) staging. LNY ≥22LN may improve survival, especially in right-sided CC [Lee et al., Surg Oncol, 27(3), 2018]. This multicentric retrospective cohort study evaluated the impact of LNY and tumor laterality on CC staging and survival.

MATERIALS AND METHODS

Patients with stage I-III CC that underwent surgery from 2012 to 2018 were grouped according to LNY: <22 and ≥ 22. Primary outcomes were LN positivity (N+ rate) and disease-free survival (DFS). Overall survival (OS) was the secondary outcome. Exploratory analyses were performed for laterality and stage.

RESULTS

We included 795 patients (417 < 22LN, 378 ≥ 22LN); 53% had left-sided CC and 29%/37%/38% had stage I/II/III tumors. There was no association between LNY ≥22LN and N+ rate after adjustment for grade, T stage, lymphovascular invasion (LVI) and perineural invasion; a trend for a higher N+ rate in left-sided CC was identified (interaction p = 0.033). With a median follow-up of 63.6 months for DFS and 73.2 months for OS, 254 patients (31.9%) relapsed and 207 (26.0%) died. In multivariate analysis adjusted for age, ASA score, laparoscopic approach, T/N stage, mucinous histology, LVI and adjuvant chemotherapy, LNY ≥22LN was significantly associated with both DFS (HR 0.75, p = 0.031) and OS (HR 0.71, p = 0.025). Restricted cubic spline analysis showed a more significant benefit for right-sided CC.

CONCLUSION

LNY ≥22LN was associated with longer DFS and OS in patients with operable CC, especially for right-sided CC.

Consensus statements on complete mesocolic excision for right-sided colon cancer-technical steps and training implications

Background

CME is a radical resection for colon cancer, but the procedure is technically demanding with significant variation in its practice. A standardised approach to the optimal technique and training is, therefore, desirable to minimise technical hazards and facilitate safe dissemination. The aim is to develop an expert consensus on the optimal technique for Complete Mesocolic Excision (CME) for right-sided and transverse colon cancer to guide safe implementation and training pathways.

Methods

Guidance was developed following a modified Delphi process to draw consensus from 55 international experts in CME and surgical education representing 18 countries. Domain topics were formulated and subdivided into questions pertinent to different aspects of CME practice. A three-round Delphi voting on 25 statements based on the specific questions and 70% agreement was considered as consensus.

Results

Twenty-three recommendations for CME procedure were agreed on, describing the technique and optimal training pathway. CME is recommended as the standard of care resection for locally advanced colon cancer. The essential components are central vascular ligation, exposure of the superior mesenteric vein and excision of an intact mesocolon. Key anatomical landmarks to perform a safe CME dissection include identification of the ileocolic pedicle, superior mesenteric vein and root of the mesocolon. A proficiency-based multimodal training curriculum for CME was proposed including a formal proctorship programme.

Conclusions

Consensus on standardisation of technique and training framework for complete mesocolic excision was agreed upon by a panel of experts to guide current practice and provide a quality control framework for future studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-021-08395-0.

The impact of tumor location on long-term survival outcomes in patients with right-sided colon cancer

BACKGROUND

The oncologic outcomes of right-sided cancers are generally grouped in studies. We hypothesized that tumor location (cecal vs. ascending vs. hepatic flexure) may influence cancer-specific outcomes.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried for patients over 18 with non-metastatic, invasive (American Joint Committee on Cancer stage I-III) right-sided adenocarcinoma of the colon from 1988 to 2014 who underwent partial colectomy. Patients were categorized into groups: (1) cecum (2) ascending colon (3) hepatic flexure. Demographic, clinical and pathologic factors were compared between groups. Disease-specific and overall survival were described using the Kaplan-Meier method and compared using the log-rank test. Multivariate Cox regression analysis determined the independent association of primary tumor location.

RESULTS

We identified 167,450 patients. Mean age was 72.2 ± 12.3 years and 54.9% were female. Of these, 81,611, 66,857, and 18,982 had cecal, ascending colon, and hepatic flexure cancers, respectively. Cecal cancers were associated with a lower number of examined nodes but a higher likelihood of nodal positivity. Cecal cancer patients were significantly older, had larger tumors, and higher tumor stage. On univariate analysis, cecal cancers were associated with poorer disease-specific and overall survival (all p values < 0.001). On multivariate analysis controlling for sex, age, tumor size, number of examined nodes and stage, hepatic flexure cancers were associated with worse disease-specific (HR 1.05) and overall survival (HR 1.03).

CONCLUSION

Hepatic flexure cancers are associated with worse survival compared to more proximal colon cancers. The cause is likely multifactorial, including biological and technical factors. More aggressive surgical and multimodal therapy may be considered for hepatic flexure colon cancers.

Survival outcomes for right-versus left-sided colon cancer and rectal cancer in England: A propensity-score matched population-based cohort study

INTRODUCTION

The aim of this study was to evaluate 5-year overall survival (OS) in patients operated on for potentially curable right versus left-sided colon cancer and rectal cancer in England.

MATERIALS AND METHODS

A retrospective propensity-score matched population-based cohort study was performed using data from English Hospital Episode Statistics, Office for National Statistics and National Bowel Cancer Audit dataset. Patients ≥18 who underwent elective resection for right-colon, left-colon, or rectal cancer between 2000 and 2015 were included. Patients were matched using propensity scores with the dependant variable being site of primary tumour (right-colon, left-colon, or rectum) and independent variables age, Charlson comorbidity index, operation year and Duke's stage. The primary outcome was 5-year overall survival (OS).

RESULTS

A total of 167,606 patients were included. Following propensity-score matching 26,662 patients remained in each group (right-colon, left-colon, and rectum). 5-year OS was significantly worse for patients with Duke's A-C right-sided primaries compared to left-sided and rectal cancers in the unmatched (58.8% vs 66.7% vs 70.0% p=<0.001) and matched cohorts (62.6%, 66.8%, 65.8% p=<0.001). Superior OS for patients with left-sided colon cancer was demonstrated across all stages (Duke's A HR 0.845, p = 0.003; Duke's B HR 0.947, p = 0.045; Duke's C HR 0.783, p < 0.0001). Secondary analysis demonstrated equivalent OS between study groups when ≥22 lymph nodes were harvested.

CONCLUSION

There is a significant difference in survival between comparable patients with right and left sided colon cancers in England. The quality and/or extent of mesenteric resection may be of particular importance in right-sided colon cancer.

Long-term Results of Surgery for Colorectal Liver Metastases in Terms of Primary Tumour Location and Clinical Risk Factors

BACKGROUND/AIM

The aim of the study was to evaluate the influence of primary tumour location and clinical risk factors for long-term results of surgery for colorectal liver metastases (CLMs).

PATIENTS AND METHODS

Overall survival (OS) and recurrence-free survival (RFS) were evaluated in 636 patients. Patients were divided by tumour location (right-/left-sided colorectal cancer: RCRC/LCRC; rectal cancer), and age, gender, number and size of CLMs, type of liver surgery and interval from primary operation were evaluated.

RESULTS

One-, 3- and 5-year OS and RFS were independent of primary tumour location (p<0.59). CLM diameter was negatively associated with OS for the whole cohort (p<0.002), and RCRC (p<0.03) and LCRC (p<0.04) groups, as well as for RFS of those with LCRC (p<0.04). CLM number was negatively associated with RFS for the whole cohort (p<0.0001), RCRC (p<0.02), LCRC (p<0.0001) and RC (p<0.02). Radiofrequency ablation and combined procedures led to worse OS for the whole cohort (p<0.03), and to worse RFS for the whole cohort (p<0.0003) and for those with LCRC (p<0.03). A shorter interval between primary colorectal cancer surgery and CLMs procedure was risky for poor OS and RFS of patients with CLMs from RCRC (p<0.05), LCRC (p<0.05) and RC (p<0.02).

CONCLUSION

Primary tumour location together with clinical risk factors are important for long-term results of surgery CLMs.

Colon cancer survival differs from right side to left side and lymph node harvest number matter

Background

Right-sided colorectal cancer (CRC) has worse survival than does left-sided CRC. The objective of this study was to further assess the impact of right-side location on survival and the role of the extent of lymphadenectomy.

Methods

All CRCs diagnosed between 2000 and 2012 in Emilia-Romagna Region, Italy, were included. Data for stage, grade, histology, screening history, and number of removed lymph nodes (LN) were collected. Multivariable Cox regression models were used to estimate hazard ratios (HR), with relative 95% confidence intervals (95%CI), of right vs. left colon and of removing < 12, 12–21 or > 21 lymph nodes by cancer site.

Results

During the study period, 29,358 patients were registered (8828 right colon, 18,852 left colon, 1678 transverse). Patients with right cancer were more often older, females, with advanced stage and high grade, and higher number of removed LNs. Five-year survival was lower in the right than in the left colon (55.2% vs 59.7%). In multivariable analysis, right colon showed a lower survival when adjusting for age, sex, and screening status (HR 1.12, 95%CI 1.04–1.21). Stratification by number of lymph nodes removed (12–21 or > 21) was associated with better survival in right colon (HR 0.54, 95%CI 0.40–0.72 and HR 0.40, 95%CI 0.30–0.55, respectively) compared to left colon (HR 0.89, 95%CI 0.76–1.06 and HR 0.83, 95%CI 0.69–1.01, respectively).

Conclusions

This study confirms that right CRC has worse survival; the association is not due to screening status. An adequate removal of lymph nodes is associated with better survival, although the direction of the association in terms of causal links is not clear.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10746-4.

Feasibility of robotic right colectomy with complete mesocolic excision and intracorporeal anastomosis: short-term outcomes of 161 consecutive patients

Technical and oncological aspects are still debated when dealing with minimally-invasive right colectomy. Main controversial issues still remain about whether the anastomosis should be performed intra- or extracorporeally and if a complete mesocolic excision (CME) should be carried out. We report the feasibility of robotic right colectomy with CME and intracorporeal anastomosis (IA) for right sided colon cancer. Data from patients who underwent robotic right colectomy with IA and CME from January 2015 to April 2020 were prospectively collected and retrospectively analyzed. Intraoperative outcomes and complications (minor I-II and major III-IV according to Clavien-Dindo classification), conversion rate, 30-day postoperative outcomes and pathological outcomes were the variables assessed. A total of 161 patients undergoing robotic right colectomy for cancer met the inclusion criteria. Mean operative time was 185 min, no intraoperative complications were observed, and the conversion rate was 3.7% (6 patients requiring elective conversions). Overall, mean postoperative stay was 4.9 days and the overall 30-day complication rate was 16.1%. 20 patients (12.4%) had minor complications, while major postoperative complications occurred in six patients (3.7%). Anastomotic leak was recorded in one patient (0.6%) and the 30-day re-admission rate was 0.6%. Mean number of harvested lymph nodes was 21.9. Patients requiring conversion experienced two minor complications, with a mean length of stay of 7 days. Robotic right colectomy with CME and IA is feasible and it is associated with good intraoperative and short-term postoperative clinical outcomes.

Minimally Invasive Surgical Approaches Are Safe and Appropriate in N2 Colorectal Cancer

BACKGROUND

There is emerging evidence of the oncological safety of minimally invasive surgery in T4 colorectal cancer; however, such support is lacking in N2 disease.

OBJECTIVE

This study aimed to compare oncological and perioperative outcomes of surgical resection for N2 colorectal cancer using an open versus minimally invasive approach.

DESIGN

We conducted a retrospective cohort study using the National Surgical Quality Improvement Program's generic and targeted colectomy data sets.

SETTINGS

Data about surgery for N2 colorectal cancer were obtained regarding North American hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program.

PATIENTS

All patients undergoing elective surgical resection for N2 colorectal cancer in participating hospitals between 2014 and 2018 were selected.

INTERVENTIONS

Surgical resection of N2 colorectal cancer was performed.

MAIN OUTCOME MEASURES

Our primary outcome was nodal yield. Secondary outcomes included perioperative complications and mortality.

RESULTS

A total of 1837 patients underwent open and 3907 patients underwent minimally invasive surgery colectomies for N2 colorectal cancer (n = 5744). Median nodal yield was 20 (interquartile range, 15-27) in the open group and 21 (interquartile range, 16-28) in the minimally invasive group (p < 0.0001); however, nodal harvest between the 2 groups was not significantly different on multivariate analysis. Perioperative complications were higher on univariate analysis in the open surgery group, with respect to key outcomes including anastomotic leak and death (p < 0.001).

LIMITATIONS

This study is limited by its retrospective design and by the fact that the staging data collected by the National Surgical Quality Improvement Program are pathological rather than clinical; however, prior studies found a 97% concordance between pathological and clinical N2 determination.

CONCLUSIONS

Minimally invasive surgery approaches to colorectal cancer with N2 disease result in equivalent nodal harvests compared with open approaches. Our group supports the use of a minimally invasive approach in advanced nodal stage colorectal cancer in the appropriately selected patient. See Video Abstract at http://links.lww.com/DCR/B417.

LOS ABORDAJES QUIRRGICOS MNIMAMENTE INVASIVOS SON SEGUROS Y APROPIADOS EN EL CNCER COLORRECTAL N

ANTECEDENTES:Existe evidencia emergente de la seguridad oncológica de la cirugía mínimamente invasiva en el cáncer colorrectal T4; sin embargo, semenjante apoyo falta en la enfermedad N2.OBJETIVO:comparar los resultados oncológicos y perioperatorios de la resección quirúrgica para el cáncer colorrectal N2 utilizando un abordaje abierto versus mínimamente invasivo.DISEÑO:Realizamos un estudio de cohorte retrospectivo utilizando los conjuntos de datos de colectomía genéricos y específicos del Programa Nacional de Mejoramiento de la Calidad Quirúrgica.AJUSTE:Hospitales de Norte America que participan en el Programa Nacional de Mejoramiento de la Calidad Quirúrgica del Colegio Americano de Cirujanos.PACIENTES:Todos los pacientes sometidos a resección quirúrgica electiva por cáncer colorrectal N2 en los hospitales participantes entre 2014 y 2018.INTERVENCIONES:Resección quirúrgica de cáncer colorrectal N2.PRINCIPALES MEDIDAS DE VOLORACION:Nuestro resultado principal fue el rendimiento nodal. Los resultados secundarios incluyeron complicaciones perioperatorias y mortalidad.RESULTADOS:1837 pacientes fueron sometidos a cirugía abierta y 3907 pacientes fueron sometidos a colectomías de cirugía mínimamente invasiva por cáncer colorrectal N2 (n = 5744). La mediana del rendimiento nodal fue 20 (IQR 15-27) en el grupo abierto y 21 (IQR 16-28) en el grupo mínimamente invasivo (p <0,0001); sin embargo, el rendimiento nodal entre los dos grupos no fue significativamente diferente en el análisis multivariado. Las complicaciones perioperatorias fueron mayores en el análisis univariado en el grupo de cirugía abierta, con respecto a los resultados clave, incluida la fuga anastomótica y la muerte (p <0,001).LIMITACIONES:Este estudio está limitado por su diseño retrospectivo y por el hecho de que los datos de estadificación recopilados por NSQIP son patológicos más que clínicos; sin embargo, estudios previos encontraron una concordancia del 97% entre la determinación patológica y clínica de N2.CONCLUSIONES:Los enfoques de cirugía mínimamente invasiva para el cáncer colorrectal con enfermedad N2 dan rendimientos nodales equivalentes a abordajes abiertos. Nuestro grupo apoya el uso de abordaje mínimamente invasivo en el cáncer colorrectal avanzado en estadio ganglionar en el paciente adecuadamente seleccionado. Consulte Video Resumenhttp://links.lww.com/DCR/B417.

Application and outcomes of a standardized lymphadenectomy in laparoscopic right hemicolectomy requiring ligation of the middle colic artery

BACKGROUND

Complete mesocolic excision with central vessel ligation may be important for accurate staging and improving the prognosis of right-sided colon cancer. Although the procedure is often performed laparoscopically, approaching the middle colic artery (MCA) is technically demanding, especially when complete ligation of arteries at their roots is desired. We standardized our laparoscopic approach by establishing the dissection boundary along the superior mesenteric artery to achieve D3 lymphadenectomy in the region of the MCA. The aim of the present study was to evaluate, on the basis of perioperative and short-term oncologic outcomes, the feasibility and safety of our technique METHODS: We conducted a retrospective study on consecutive patients with cancer located at the ascending colon and transverse colon who had laparoscopic right hemicolectomy requiring ligation of the MCA.

RESULTS

There were 41 patients (22 males, median age 71 years [range 49-86] years). The median operation time was 285 min, and blood loss volume was 40 mL. Conversion to open surgery was required in 1 case. Complications that were Clavien-Dindo grade III or above occurred in 3 patients (7.3%). There was no anastomotic leakage. The median number of lymph nodes harvested was 46.

CONCLUSIONS

Our technique was shown to be a safe, feasible, and useful strategy for performance of right hemicolectomy requiring ligation of the MCA in cases of colon cancer. The technique facilitates maximal lymph node dissection. Having obtained favorable outcomes, we look forward to investigation into long-term outcomes.

Examining More Lymph Nodes May Improve the Prognosis of Patients With Right Colon Cancer: Determining the Optimal Minimum Lymph Node Count

OBJECTIVES

The objective is to determine the optimal minimum lymph node examination number for right colon cancer (RCC) patients.

METHODS

We comprehensively analysed the Surveillance, Epidemiology and End Results database data from 2004 to 2016 to determine the 13-year trend in the number of lymph nodes examined among 108,703 left colon cancer and 165,937 RCC patients. 133,137 RCC patients eligible for inclusion were used to determine the optimal minimum for lymph node examination. We used restricted cubic splines to analyse the dose-response relationship between the number of lymph nodes examined and prognosis. X-tiles and decision trees were used to determine the optimal cutoff for the number of lymph nodes based on the survival outcomes of patients with RCC. The Kaplan-Meier method and COX model were used to estimate the overall survival and independent prognostic factors, and a prediction model was constructed. The C-index, calibration curve, net reclassification improvement and integrated discrimination improvement were used to determine the predictive performance of the model, and decision curve analysis was used to evaluate the benefits.

RESULTS

Lymph node examinations were common among colon cancer patients over the 13-year study period. It is generally agreed that at least 12 lymph nodes must be examined to ensure proper dissection and accurate staging of RCC; however, the optimal number of lymph nodes to be examined is controversial. The dose-response relationship indicated that 12 was not the optimal minimum number of lymph nodes for RCC patients. X-tile and survival decision-tree analysis indicated that 20 nodes was the optimal number. Survival analysis indicated that <20 nodes examined was a risk factor for poor prognosis, and the classification performance was superior for 20 nodes compared to 12 nodes.

CONCLUSION

Lymph node examination in RCC patients should be altered. Our research suggests that a 20-node measure may be more suitable for RCC patients.

Efficacy and safety of capecitabine and oxaliplatin (CAPOX) treatment in colorectal cancer: An observational study from a tertiary cancer center in South India

Background

5-fluorouracil (5-FU) was the standard treatment care for colorectal cancer (CRC), however, its efficacy was limited due to safety concerns. Capecitabine and oxaliplatin (CAPOX) treatment was found equivalent to 5-FU in efficacy and preferred now due to easy management and convenience in administration. Hence, the present study aims to determine the efficacy and safety associated with CAPOX treatment in a real world non clinical setting.

Methods

145 treatment-naive and newly diagnosed CRC patients were recruited in the study. Each patient received oxaliplatin 130 mg/m² infusion over 2 hours on day 1 and oral capecitabine 1000 mg/m² in divided doses twice daily for the next 14 days of a 21-day cycle.

Results

In the adjuvant setting, the observed disease-free survival rate was 62% (n=34) in the colon and 67% (n=15) in the rectum cancer patients at 2 years. The observed overall survival rate in the colon and rectal cancer was 80% (n=44) and 83% (n=18) respectively at 2 years. In the palliative setting the observed progression-free survival rate was 28% (n=13) in the colon and 33% (n=7) in rectal cancer patients at 2 years. The observed OSR at 2 years was 64% (n=30) in the colon and 67% (n=14) in the rectal cancer patients. Thrombocytopenia (17, 11.7%) and diarrhea (8, 5.5%) were the most commonly observed grade 3/4 hematological and gastrointestinal toxicities. Hand-foot syndrome and peripheral neuropathy were the major contributors for dose reduction (14, 9.6%), treatment delay (8, 5.4%), and drug discontinuation (9, 6.1%) in the study cohort.

Conclusion

CAPOX treatment was found to be effective but associated with several dose-limiting toxicities.

Prospective analysis of tumor spread to the small bowel mesentery in cases of right-sided colon cancer

PURPOSE

Guidelines advocate minimal ileal resection when right hemicolectomy is performed for right-sided colon cancer. The practice, thought to prevent malabsorption syndrome, does not appear to foster local recurrence. Little evidence based on rigorous study exists, however. To understand the pattern of lymphatic spread of right-sided colon cancer toward the small bowel and thus determine the appropriate margin size, we prospectively investigated anatomical distribution of lymph nodes (LNs) in the small bowel mesentery and of metastasis to these nodes in patients with right-sided colon cancer treated by such surgery.

METHODS

In each case, the mesenteric specimen, which had been dissected along the ileocolic vessels and included intermediate LNs, was divided into 2 areas: that 0-3 cm from the vessel pedicle (area 1) and that 3-5 cm from the pedicle (area 2). The peri-intestinal mesentery was cut into 9 segments.

RESULTS

Ninety-one patients were included in the study. Overall, 3366 LNs were dissected. Four hundred fifty-three of these LNs were located in area 1 (90 cases), and 15 (3.3%) were metastatic. Only 63 LNs were located in area 2 (34 cases; average of 0.69 per patient); none was metastatic. Overall, 269 LNs were found in the small bowel mesentery (in 56 of the 91 patients). Only 4 were positive (3 cases), and all were within 5 cm of the ileocecal valve.

CONCLUSION

Our data indicate that a surgical margin 3 cm from the ileocecal pedicle and a short (5 cm) ileal margin are oncologically reasonable for effective right hemicolectomy.

Impact of Primary Tumor Location on Survival After Curative Resection in Patients with Colon Cancer: A Meta-Analysis of Propensity Score-Matching Studies

BACKGROUND

Recent retrospective subgroup analyses of patients with unresectable colon cancer (CC) receiving systemic chemotherapy have demonstrated that there is a significant difference in treatment outcome between patients with right-sided CC (RSCC) and those with left-sided CC (LSCC). However, it is impossible to divide patients with CC randomly into RSCC and LSCC groups before surgery. Therefore, the aim of this study is to explore the impact of primary tumor location (PTL) on survival after curative surgery for patients with CC using propensity score-matching (PSM) studies instead of randomization.

MATERIALS AND METHODS

We performed a comprehensive electronic search of the literature up to January 2019 to identify studies that had used databases allowing comparison of postoperative survival between patients with RSCC and those with LSCC. To integrate the impact of PTL on 5-year overall survival (OS) after curative surgery, a meta-analysis was performed using random-effects models to calculate the risk ratio (RR) and 95% confidence interval (CI) for the selected PSM studies.

RESULTS

Five studies involving a total of 398,687 patients with CC were included in this meta-analysis. Among 205,641 patients with RSCC, 69,091 (33.6%) died during the observation period, whereas among 193,046 patients with LSCC, 63,380 (32.8%) died during the same period. These results revealed that patients with RSCC and those with LSCC had almost the same 5-year OS (RR, 0.98; 95% CI, 0.89-1.07; p = .64; I² = 97%).

CONCLUSION

This meta-analysis has demonstrated that there was no significant difference in 5-year OS between patients with RSCC and those with LSCC after curative resection.

IMPLICATIONS FOR PRACTICE

To integrate the impact of primary tumor location (PTL) on 5-year overall survival (OS) after curative surgery, five propensity score-matching (PSM) studies involving a total of 398,687 patients with colon cancer (CC) were included in this meta-analysis. Among 205,641 patients with right-sided CC (RSCC), 69,091 (33.6%) died during the observation period, whereas among 193,046 patients with left-sided CC (LSCC), 63,380 (32.8%) died during the same period. These results revealed that patients with RSCC and those with LSCC had almost the same 5-year OS (risk ratio, 0.98; 95% confidence interval, 0.89-1.07; p = .64; I² = 97%).

Personalized Adjuvant Treatment of Colon Cancer

Introduction

Colon cancer (CC) is one of the most frequent malignant diseases. Adjuvant chemotherapy is of utmost importance in the management of localized disease. With the emergence of precision medicine, treatment approaches are becoming increasingly personalized and complex. This review contributes to a broader understanding of the role and relevance of personalized adjuvant treatment strategies in colon carcinoma, and summarizes the current status in this disease entity.

Methods

We searched the websites ClinicalTrials.gov, PubMed, and ASCO (American Society of Medical Oncology) Meeting Library for clinical trials and retrospective analyses in the field of adjuvant treatment of CC with special attention to personalized approaches.

Results

Various factors, including gender, age, sidedness, stage, dMMR/MSI-H, mutations, molecular profile, CMS, immunoscore, minimal residual disease, type of adjuvant therapy, therapy duration, and the patient's wish play an important role in the adjuvant setting of CC and should be considered in treatment decision making.

Conclusion

Future molecular profiling ideally assessed and monitored by liquid biopsy might personalize decision making even more in the adjuvant setting of CC patients. Further research and clinical trials are needed to clarify relevant questions and to highlight important clinical aspects.

Effect of primary colorectal cancer tumor location on survival after pulmonary metastasectomy

OBJECTIVES

Although colorectal cancer bowel segment location has been shown to independently predict the outcomes in early stage disease, it has not been previously studied in the setting of pulmonary metastases. We sought to determine whether colorectal cancer location affects survival after pulmonary metastasectomy.

METHODS

Patients who had undergone pulmonary metastasectomy for colorectal cancer at a single institution from 2011 to 2018 were reviewed. Univariable and multivariable Cox regression analyses were performed to identify predictors of overall survival and disease-free survival. The Kaplan-Meier survival method was used to determine differences between groups.

RESULTS

A total of 194 patients were evaluated. The median follow-up, survival time, and 5-year survival rate were 36.8 months, 75.8 months, and 57%, respectively, and 122 patients (63%) had experienced disease recurrence at any location. On univariable analysis, age, primary tumor location, pulmonary nodule size, ≥3 pulmonary nodules, and intrathoracic nodal disease were associated with overall survival. On multivariable analysis, patients with left-sided tumors experienced a survival benefit (hazard ratio, 0.31; P = .036). Kaplan-Meier analysis revealed a median survival time of 90 months (95% confidence interval, 82 months to not reached) compared with 55 months (95% confidence interval, 49 months to not reached) for patients with left-sided and rectal tumors, respectively, after metastasectomy (P = .078). Location was not associated with disease-free survival on Cox multivariable regression.

CONCLUSIONS

We found that left-sided colorectal cancer is associated with prolonged survival after pulmonary metastasectomy. Future investigations are required to determine the validity of such findings, including the effect of location in the prognostication for patients who are candidates for pulmonary metastasectomy.

Tumor sidedness influences prognostic impact of lymph node metastasis in colon cancer patients undergoing curative surgery

This study aimed to evaluate prognostic impacts of the number of lymph nodes (LNs) examined and LN ratio on cancer-specific mortality after surgery in patients with right-sided colon cancer (RCC) or left-sided colon cancer (LCC) using the Surveillance, Epidemiology, and End Results database. Number of LNs examined and LN ratio were treated as categorical and/or continuous. Competing risks proportional hazards regressions adjusted by propensity score were performed. All included patients had stage I, II, or III disease, and 45.1% of them had RCC. RCC and LCC patients with high level of LNs examined had better prognosis after segmental resection or hemicolectomy. RCC and LCC patients with higher LN ratio had worse prognosis regardless of surgery. Survival benefit of having high level of LNs examined was observed in RCC patients with stage I, II, or III disease, but only in LCC patients with stage II disease. Both higher LN ratio and high level of LN were negative prognostic factors for cancer-specific mortality in stage III patients regardless of tumor sidedness. In conclusion, RCC patients in various conditions had worse or comparable prognosis compared to their LCC counterparts, which reflected the severity of LN metastasis.

Are right-sided colectomies for neoplastic disease at increased risk of primary postoperative ileus compared to left-sided colectomies? A coarsened exact matched analysis

INTRODUCTION

The objective of this study was to determine whether right-sided colectomies (RC) were associated with a higher incidence of primary postoperative ileus (pPOI) compared to left-sided colectomies (LC).

METHODS

Patients who underwent elective colectomy for neoplastic disease between 2012 and 2016 were identified using the American College of Surgeons National Surgical Quality Improvement Program database. RC and LC were defined as having an ileocolic or colocolic/colorectal anastomosis, respectively. Coarsened Exact Matching (CEM) was used to balance the two groups (1:1) on important confounders. The association between type of colectomy and pPOI, defined as POI in the absence of intra-abdominal sepsis, was then assessed in a multiple logistic regression analysis of the matched data.

RESULTS

Of 40,636 patients who underwent a colectomy for neoplastic disease, 15,231 underwent a RC and 25,405 a LC. After CEM, 12,949 matched patients remained in each group, and all important confounders were well balanced. The incidence of pPOI was higher in the RC group (11.5% vs. 8.8%, p < 0.001). On multiple logistic regression, RC was associated with a 35% higher odds of developing pPOI compared to LC (OR 1.35, 95% CI 1.25-1.47). RC was also associated with increased risk for NSQIP-defined major morbidity (OR 1.10, 95% CI 1.01-1.20), 30-day readmission (OR 1.16, 95% CI 1.06-1.27), and increased length of stay (β = 0.16 days, 95% CI 0.11-0.22).

CONCLUSION

pPOI is more common after RC than LC. Future research should aim at better understanding the pathophysiology behind this increased risk and identifying interventions to mitigate pPOI in this population.

5-year outcome after complete mesocolic excision for right-sided colon cancer: a population-based cohort study

BACKGROUND

The benefits of extensive lymph node dissection as performed in complete mesocolic excision are still debated, although recent studies have shown an association with improved long-term outcomes. However, none of these studies had an intention-to-treat design or aimed to show a causal effect; therefore in this study, we aimed to estimate the causal oncological treatment effects of complete mesocolic excision on right-sided colon cancer.

METHODS

We did a population-based cohort study involving prospective data collected from four hospitals in Denmark. We compared the oncological outcome data of patients at one centre performing central lymph node dissection and vascular division after almost complete exposure of the proximal part of the superior mesenteric vein (ie, the complete mesocolic excision group) with three other centres performing conventional resections with unstandardised and limited lymph node dissection (ie, non-complete mesocolic excision; control group). We included data for all patients in the Capital Region of Denmark undergoing elective curative-intent right-sided colon resections for stages I-III colon cancer, as categorised by the Union for International Cancer Control (UICC; 5th edition), from June 1, 2008, to Dec 31, 2013. Patients were followed-up for 5·2 years after surgery. The primary outcome was the cumulative incidence of recurrence after 5·2 years of surgery. Inverse probability of treatment weighting and competing risk analyses were used to estimate the possible causal effects of complete mesocolic excision. This study is registered with ClinicalTrials.gov, number NCT03754075.

FINDINGS

1069 patients (813 in the control group and 256 in the complete mesocolic excision group) underwent curative-intent elective surgery for right-sided colon cancer during the study period. None of the patients were lost to follow-up regarding survival or recurrence status, and consequently no patient was censored in the analyses. The 5·2-year cumulative incidence of recurrence was 9·7% (95% CI 6·3-13·1) in the complete mesocolic excision group compared with 17·9% (15·3-20·5) in the control group, and the absolute risk reduction of complete mesocolic excision after 5·2 years was 8·2% (95% CI 4·0-12·4; p=0·00015). In the control group, 145 (18%) of 813 patients were diagnosed with a recurrence and 281 (35%) died during follow-up, whereas in the complete mesocolic excision group 25 (10%) of 256 patients were diagnosed with a recurrence and 75 (29%) died during follow-up.

INTERPRETATION

This study shows a causal treatment effect of central mesocolic lymph node excision on risk of recurrence after resection for right-sided colon adenocarcinoma. Complete mesocolic excision has the potential to reduce the risk of recurrence and improve long-term outcome after resection for all UICC stages I-III of right-sided colon adenocarcinomas.

FUNDING

The Tvergaard Fund, Helen Rude Fund, Krista and Viggo Petersen Fund, Olga Bryde Nielsen Fund, and Else and Mogens Wedell-Wedellsborg Fund.

Adjuvant therapy for stages II and III colon cancer: risk stratification, treatment duration, and future directions

Background

To date, the role of adjuvant systemic therapy in stages ii and iii colon cancer remains a topic of interest and debate. The objective of the present review was to assess the most recent data, specifically addressing methods of risk stratification, duration of therapy, and future directions.

Methods

PubMed and medline were searched for literature pertinent to adjuvant chemotherapy in either stage ii or stage iii colorectal cancer.

Summary

Locoregional disease, histopathology, age, laterality, and a number of other biologic and molecular markers appear to have a role in disease risk stratification. The duration of adjuvant therapy for stage iii disease can vary based on risk factors, but use of adjuvant therapy and duration of therapy in stage ii disease remain controversial. Future directions should include genomic assays and improved study design to provide concrete evidence about the duration of adjuvant folfox or capox and about other types of chemotherapy and immunotherapy.

Accuracy of nodal staging is influenced by sidedness in colon cancer

Background

Adequate lymph node (LN) sampling is critical for accurate nodal staging in colon cancer (CC), particularly for T3N0 disease as current guidelines recommend considering adjuvant chemotherapy when less than 12 LNs are examined. The impact of sidedness on nodal staging accuracy in patients with T3N0 disease has not been previously studied.

Methods

Patients with pathologic T3 CC were identified from a prospective multicenter international trial of ultrastaging in CC. The probability of true nodal negativity (TNN) based on the number of LN examined was calculated for right and left CC. These results were then validated in a cohort of patients with similar inclusion criteria selected from the National Cancer Database (NCDB) between 2006 and 2014.

Results

Three hundred and seventy patients met the inclusion criteria in the trial cohort; 48% were LN-negative. Of 153,945 patients in the NCDB, 57% were LN-negative. The probability of TNN when 12 LNs were examined was 68% for right and 64% for left CC in the trial cohort and 77% and 72% in the NCDB. The number of LNs needed to achieve any given probability of TNN was significantly different between right and left CC in both the trial (P<0.001) and the NCDB (P<0.001).

Conclusions

In both a prospective multicenter trial and the NCDB, sidedness influences the number of LNs needed to predict nodal negativity in CC. Current guidelines regarding the minimum number of LNs needed to accurately stage patients with T3N0 CC may need to be re-evaluated by taking into consideration the tumor sidedness.