The prognostic value of lymph node ratio in a population-based collective of colorectal cancer patients. Ann Surg. 2010;251:1070-1078. [PMID: 20485149 DOI: 10.1097/sla.0b013e3181d7789d]

Survival analysis in pT1-3 and paracolic lymph-node invasion colorectal cancer: the prognostic role of positive paracolic lymph-node ratio for adjuvant chemotherapy

PURPOSE

Several studies have observed that some stage III colorectal cancer (CRC) patients cannot benefit from standard adjuvant chemotherapy. However, there is no unified screening standard to date.

METHODS

Consecutive patients with pathologically confirmed colon adenocarcinoma treated in 3 centers between January 2016 and December 2018 were included. Patients were divided into four groups according to different stages and positive paracolic lymph-node ratio (P-LNR) [Cohort 1: pT1-3N0M0, Cohort 2: pT1-3N + (P-LNR ≤ 0.15)M0, Cohort 3: pT4N0M0, Cohort 4: stage III patients except for pT1-3N + (P-LNR ≤ 0.15)M0], and further overall survival was compared by Kaplan-Meier method. The univariate and multivariate analyses were employed for cox proportional hazards model.

RESULTS

We retrospectively reviewed 5581 consecutive CRC patients with, and 2861 eligible patients were enrolled for further analysis. The optimal cut-off value of P-LNR in our study was 0.15. There was no significant difference in OS (91.36 vs. 93.74%) and DFS (87.65 vs. 90.96%) between stage III patients with pT1-3N + (P-LNR ≤ 0.15)M0 and those with pT1-3N0M0. Further analysis demonstrated that CRC patients with pT1-3N + (P-LNR ≤ 0.15)M0 were less likely to benefit from 8 cycles of CAPOX or FOLFOX chemotherapy and suffered fewer adverse events from declining chemotherapy. Comparing with 0-4 cycles versus 8 cycles, the overall survival rates were 91.35 versus 90.19% (P = 0.79), and with a DFS of 87.50 versus 88.24% (P = 0.49), the duration of adjuvant chemotherapy was not an independent risk factor for patients with pT1-3N + (P-LNR ≤ 0.15)M0 (HR: 0.70, 95% CI 0.90-1.30, P = 0.42).

CONCLUSION

The concept of P-LNR we proposed might have a high clinical application value and accurately enable clinicians to screen out specific CRC patients who decline or prefer limited chemotherapy.

TRIAL REGISTRY

The clinical trial registration number: ChiCTR2300076883.

Construction of a nomogram based on clinicopathologic features to predict the likelihood of No. 253 lymph node metastasis in rectal cancer patients

PURPOSE

To explore the high-risk factors for rectal cancer No.253 lymph node metastasis (LNM) and to construct a risk nomogram for the individualized prediction of No.253 LNM.

METHODS

This was a retrospective analysis of 425 patients with rectal cancer who underwent laparoscopic-assisted radical surgery. Independent risk factors for rectal cancer No.253 LNM was identified using multivariate logistic regression analysis, and a risk prediction nomogram was constructed based on the independent risk factors. In addition, the performance of the model was evaluated by discrimination, calibration, and clinical benefit.

RESULTS

Multivariate logistic regression analysis showed that No.253 lymphadenectasis on CT (OR 10.697, P < 0.001), preoperative T4-stage (OR 4.431, P = 0.001), undifferentiation (OR 3.753, P = 0.004), and preoperative Ca199 level > 27 U/ml (OR 2.628, P = 0.037) were independent risk factors for No.253 LNM. A nomogram was constructed based on the above four factors. The calibration curve of the nomogram was closer to the ideal diagonal, indicating that the nomogram had a better fitting ability. The area under the ROC curve (AUC) was 0.865, which indicated that the nomogram had high discriminative ability. In addition, decision curve analysis (DCA) showed that the model could show better clinical benefit when the threshold probability was between 1% and 50%.

CONCLUSION

Preoperative No.253 lymphadenectasis on CT, preoperative T4-stage, undifferentiation, and elevated preoperative Ca199 level were found to be independent risk factors for the No.253 LNM. A predictive model based on these risk factors can help surgeons make rational clinical decisions.

Early-onset locally advanced rectal cancer characteristics, a practical nomogram and risk stratification system: a population-based study

Background

The purpose of this study is to construct a novel and practical nomogram and risk stratification system to accurately predict cancer-specific survival (CSS) of early-onset locally advanced rectal cancer (EO-LARC) patients.

Methods

A total of 2440 patients diagnosed with EO-LARC between 2010 and 2019 were screened from the Surveillance, Epidemiology, and End Results (SEER) database. The pool of potentially eligible patients was randomly divided into two groups: a training cohort (N=1708) and a validation cohort (N=732). The nomogram was developed and calibrated using various methods, including the coherence index (C-index), receiver operating characteristic curve (ROC), calibration curves, and decision curves (DCA). A new risk classification system was established based on the nomogram. To compare the performance of this nomogram to that of the American Joint Committee on Cancer (AJCC) staging system, DCA, net reclassification index (NRI), and integrated discrimination improvement (IDI) were employed.

Result

Seven variables were included in the model. The area under the ROC curve (AUC) for the training cohort was 0.766, 0.736, and 0.731 at 3, 6, and 9 years, respectively. Calibration plots displayed good consistency between actual observations and the nomogram's predictions. The DCA curve further demonstrated the validity of the nomination form in clinical practice. Based on the scores of the nomogram, all patients were divided into a low-risk group, a middle-risk group, and a high-risk group. NRI for the 3-, 6-, and 9-year CSS(training cohort: 0.48, 0.45, 0.52; validation cohort: 0.42, 0.37, 0.37), IDI for the 3-, 6-, and 9-year CSS (training cohort: 0.09, 0.10, 0.11; validation cohort: 0.07, 0.08, 0.08). The Kaplan-Meier curve revealed that the new risk classification system possesses a more extraordinary ability to identify patients in different risk groups than the AJCC staging.

Conclusion

A practical prognostic nomogram and novel risk classification system have been developed to efficiently predict the prognosis of EO-LARC. These tools can serve as a guide to individualize patient treatment and improve clinical decision-making.

Impact of DNA mismatch repair proteins deficiency on number and ratio of lymph nodal metastases in colorectal adenocarcinoma

BACKGROUND

Approximately 15 % of colorectal adenocarcinomas (CRCs) are characterized by an altered expression of DNA mismatch repair (MMR) proteins (i.e. MMR deficiency [MMRd]). Lymph node ratio (LNR) represents one of the most important prognostic markers in non-advanced CRCs. No significant data are available regarding LNR distribution depending on MMR status.

PURPOSE OF THE STUDY

The aim of the present work was to compare pathological and clinical characteristics of MMRd tumors versus MMR proficient (MMRp) cases. Particular attention was paid to how these molecular sub-groups relate to the LNR.

MATERIALS AND METHODS

A mono-Institutional series of 1037 consecutive surgically treated stage I-IV CRCs were retrospectively selected and data were obtained from pathological reports. Cases were characterized for MMR/MSI status by means of immunohistochemistry or for microsatellite instability (MSI) analysis.

RESULTS

MMRd/MSI tumors (n = 194; 18.7 %) showed significant differences in comparison to MMRp lesions for sex (female prevalence 50.5 % vs 40.7 %; p = 0.013), age (74.2 vs 69.2; p < 0.001), location (right side; p < 0.001), diameter (larger than MMRp; p < 0.001), growth pattern (expansive pattern of growth; p < 0.001), peri- (p = 0.0002) and intra-neoplastic (p = 0.0018) inflammatory infiltrate, presence of perineural invasion (p < 0.001), stage (lower stage at presentation; p < 0.001), grade (higher prevalence of high-grade tumors; p < 0.001), and LNR (lower; p < 0.001).

CONCLUSIONS

MMRd/MSI tumors are a distinct molecular CRC subtype characterized by a significantly lower LNR in comparison to MMRp lesions. These data further support the prognostic impact of MMRd/MSI status in early-stage CRCs.

Real-world survival of colon cancer after radical surgery: A single-institutional retrospective analysis

The survival rate for colon cancer after radical surgery has been the focus of extensive debate. To assess the postoperative survival and prognostic factors for overall survival (OS), we collected clinicopathological information for 2,655 patients. The survival time and potential risk factors for OS were analyzed by using Kaplan–Meier curves, Cox proportional hazards models, best subset regression (BSR), and least absolute shrinkage and selection operator (LASSO). The 5-year survival rates of stage I–IV colon cancer were 96.6%, 88.7%, 69.9%, and 34.3%, respectively. Adjuvant chemotherapy improved the survival rate (90.4% vs. 82.4%, with versus without adjuvant chemotherapy, respectively) in stage II patients with high-risk factors. Elevated preoperative carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) were significantly associated with worse OS compared with patients without these elevations. Less than 12 versus more than 12 harvested lymph nodes (LNs) affected prognosis (84.6% vs. 89.7%, respectively). Regarding the lymph node ratio (LNR), the 5-year OS rate was 89.2%, 71.5%, 55.8%, and 34.5% in patients with LNR values of 0, 0.3, 0.3–0.7, and &gt;0.7, respectively. We constructed a nomogram comprising the independent factors associated with survival to better predict prognosis. On the basis of these findings, we propose that stage II colon cancer patients without high-risk factors and with both elevated preoperative CEA and CA199 should receive adjuvant therapy. Furthermore, the LNR could complement TNM staging in patients with &lt;12 harvested LNs. Our nomogram might be useful as a new prognosis prediction system for colon cancer patients.

Construction of a new clinical staging system for colorectal cancer based on the lymph node ratio: A validation study

Aim

This study aims to construct a new staging system for colorectal cancer (CRC) based on the lymph node ratio (LNR) as a supplement to the American Joint Committee on Cancer (AJCC) tumor node metastasis (TNM) staging system for predicting the prognosis of CRC patients with <12 lymph nodes.

Methods

The data of 26,695 CRC patients with <12 lymph nodes were extracted from the Surveillance, Epidemiology, and End Results (SEER) database as a training set. A total of 635 CRC patients were also enrolled from Northern Jiangsu People's Hospital affiliated with Yangzhou University as an independent validation set. Classification and regression tree analysis was used to obtain the LNR cutoff value. Survival curves were estimated using the Kaplan–Meier method, and the log-rank test was used for comparisons of differences among the survival curves. The monotonic decreasing trend of the overall survival curve in the staging system was expressed by the linear correlation degree R.

Results

The 5-year survival rates of patients in the training set based on the AJCC staging system from stage I to stage IV were 75.6% (95%CI: 74.4–76.8), 59.8% (95%CI: 58.6–61.0), 42.1% (95%CI: 34.5–49.7), 33.2% (95%CI: 24.6–41.8), 72.0% (95%CI: 69.1–74.9), 48.8% (95%CI: 47.4–50.2), 26.5% (95%CI: 23.0–30.0), and 11.3% (95%CI: 10.3–12.3). The 5-year survival rates of patients in the training set from stage I to stage IIIC were 80.4%, 72.9%, 59.8%, 48.4%, 32.5%, and 15.0%, according to the TNM + LNR (TNRM) staging system. According to the AJCC staging system, the 5-year survival rates of patients in the validation set from stage I to stage IIIC were 91.3%, 90.8%, 72.6%, 61.3%, 72.4%, 58.1%, and 32.8%. Based on the TNRM staging system, the 5-year survival rates of patients in the validation set from stage I to stage IIIC were 99.2%, 90.5%, 81.4%, 78.6%, 60.2%, and 35.8%.

Conclusion

The TNRM staging system successfully eliminated “survival paradox” in the AJCC staging system, which might be superior to the AJCC staging system.

Prognostic value of LODDS in medullary thyroid carcinoma based on competing risk model and propensity score matching analysis

Log odds of positive lymph nodes (LODDS) is an independent prognostic factor for patients with medullary thyroid carcinoma (MTC). However, the optimal cutoff value for LODDS needs to be further confirmed, and previous studies have ignored the prevalent competing events of non-cancer deaths among patients with MTC, thus possibly overestimating the risk of death from cancer. The information of patients with MTC who underwent total thyroidectomy was collected from SEER database. Restricted cubic splines (RCS) were used to determine the optimal cutoff for LODDS. Moreover, patients' overall survival (OS) and disease-specific survival (DSS) were determined using Kaplan-Meier and Cox proportional-hazards model. The competing risk models (CRM) were used to reduce the effect of competing events, and propensity score matching was performed to balance the confounding factors between groups. The cutoff value of LODDS determined by RCS was - 1.004, and a total of 2314 patients with MTC were recruited. In the CRM after PSM, factors such as age over 55 years at diagnosis, being male, treatment with chemotherapy or radiotherapy, unknown tumor size, and LODDS > - 1.004 were significantly associated with poor prognosis of patients both in univariate and multivariate analyses, while the presence of multifocal tumor indicated better prognosis. Patients with MTC who were over 55 years old at diagnosis, were male, received chemotherapy or radiation, had an unclear initial tumor size, and had LODDS > - 1.004 had a worse prognosis than patients with multifocal tumor.

Lymph Node Cluster Dissection After Carbon Nanoparticles Injection Enhances the Retrieval Number in Colorectal Cancer

For colorectal cancer patients, NCCN recommended that at least 12 lymph nodes should be detected since the number and metastases status of lymph nodes played an important role in the treatment and prognostic. Carbon nanoparticles have been proved to be an efficient lymph node tracer. Faced with the clinical problem of insufficient lymph nodes in colorectal cancer, we proposed a lymph node cluster (D3, D2 and D1) dissection method combined with carbon nanoparticle injection. In our study, patients were divided into 2 groups (CNP and control). All lymph nodes of each patient were collected and made into hematoxylin-eosin sections to observe their size, staining appearance and metastasis status under the microscope. As a result, the total lymph nodes in CNP group were greatly higher than control group (51.45 vs. 29.62, P = 0.000), especially micro LNs and positive micro LNs. Compared with D2 and D1 stations, fewer lymph nodes were found in D3, and it was the same for cancer metastasis status. In CNP group, most lymph nodes got black for quick visualization. In conclusion, lymph node cluster dissection combined with carbon nanoparticles could enhance the number of lymph node retrieval.

Consensus molecular subtype differences linking colon adenocarcinoma and obesity revealed by a cohort transcriptomic analysis

Colorectal cancer (CRC) is the third-leading cause of cancer-related deaths in the United States and worldwide. Obesity—a worldwide public health concern—is a known risk factor for cancer including CRC. However, the mechanisms underlying the link between CRC and obesity have yet to be fully elucidated in part because of the molecular heterogeneity of CRC. We hypothesized that obesity modulates CRC in a consensus molecular subtype (CMS)-dependent manner. RNA-seq data and associated tumor and patient characteristics including body weight and height data for 232 patients were obtained from The Cancer Genomic Atlas–Colon Adenocarcinoma (TCGA-COAD) database. Tumor samples were classified into the four CMSs with the CMScaller R package; body mass index (BMI) was calculated and categorized as normal, overweight, and obese. We observed a significant difference in CMS categorization between BMI categories. Differentially expressed genes (DEGs) between obese and overweight samples and normal samples differed across the CMSs, and associated prognostic analyses indicated that the DEGs had differing associations on survival. Using Gene Set Enrichment Analysis, we found differences in Hallmark gene set enrichment between obese and overweight samples and normal samples across the CMSs. We constructed Protein-Protein Interaction networks and observed differences in obesity-regulated hub genes for each CMS. Finally, we analyzed and found differences in predicted drug sensitivity between obese and overweight samples and normal samples across the CMSs. Our findings support that obesity impacts the CRC tumor transcriptome in a CMS-specific manner. The possible associations reported here are preliminary and will require validation using in vitro and animal models to examine the CMS-dependence of the genes and pathways. Once validated the obesity-linked genes and pathways may represent new therapeutic targets to treat colon cancer in a CMS-dependent manner.

The Effect of Lymph Node Harvest on Prognosis in Locally Advanced Middle-Low Rectal Cancer After Neoadjuvant Chemoradiotherapy

OBJECTIVE

The purpose of this study was to investigate the relationship between lymph node harvest and the prognosis in locally advanced rectal cancer (LARC) patients after neoadjuvant chemoradiotherapy (nCRT).

METHODS

Patients who were diagnosed with clinical LARC and treated with nCRT and radical surgery between June 2008 and July 2017 were included in this study. The relationship between lymph node retrieval and prognosis was analyzed. Other lymph node-related indicators were explored.

RESULTS

A total of 837 patients with a median follow-up of 61 (7-139) months were included in the study. The five-year DFS and OS rates of all patients were 74.9% and 82.3%, respectively. Multivariate survival analysis suggested that dissection of ≥ 12 lymph nodes did not improve OS or DFS. 7 was selected as the best cutoff value for the total number of lymph nodes retrieved by Cox multivariate analysis (χ2 = 10.072, HR: 0.503, P=0.002). Dissection of ≥ 5 positive lymph nodes (PLNs) was an independent prognostic factor for poorer DFS (HR: 2.104, P=0.004) and OS (HR: 3.471, p<0.001). A positive lymph node ratio (LNR) of more than 0.29 was also an independent prognostic factor for poorer DFS (HR: 1.951, P=0.002) and OS (HR: 2.434, p<0.001).

CONCLUSION

The recommends that at least 7 harvested lymph nodes may be more appropriate for LARC patients with nCRT. PLN and LNR may be prognostic factors for LARC patients with ypN+ after nCRT.

Current Perspectives on the Importance of Pathological Features in Prognostication and Guidance of Adjuvant Chemotherapy in Colon Cancer

There is not a clear consensus on which pathological features and biomarkers are important in guiding prognosis and adjuvant therapy in colon cancer. The Pathology in Colon Cancer, Prognosis and Uptake of Adjuvant Therapy (PiCC UP) Australia and New Zealand questionnaire was distributed to colorectal surgeons, medical oncologists and pathologists after institutional board approval. The aim of this study was to understand current specialist attitudes towards pathological features in the prognostication of colon cancer and adjuvant therapy in stage II disease. A 5-scale Likert score was used to assess attitudes towards 23 pathological features for prognosis and 18 features for adjuvant therapy. Data were analysed using a rating scale and graded response model in item response theory (IRT) on STATA (Stata MP, version 15; StataCorp LP). One hundred and sixty-four specialists (45 oncologists, 86 surgeons and 33 pathologists) participated. Based on IRT modelling, the most important pathological features for prognosis in colon cancer were distant metastases, lymph node metastases and liver metastases. Other features seen as important were tumour rupture, involved margin, radial margin, CRM, lymphovascular invasion and grade of differentiation. Size of tumour, location, lymph node ratio and EGFR status were considered less important. The most important features in decision making for adjuvant therapy in stage II colon cancer were tumour rupture, lymphovascular invasion and microsatellite instability. BRAF status, size of tumour, location, tumour budding and tumour infiltrating lymphocytes were factored as lesser importance. Biomarkers such as CDX2, EGFR, KRAS and BRAF status present areas for further research to improve precision oncology. This study provides the most current status on the importance of pathological features in prognostication and recommendations for adjuvant therapy in Australia and New Zealand. Results of this nationwide study may be useful to help in guiding prognosis and adjuvant treatment in colon cancer.

Prognostic Value of Lymph Node Ratio in Patients with Resected Synchronous Colorectal Liver Metastases and Less Than 12 Examined Lymph Nodes

BACKGROUND

Recent studies suggest that lymph node ratio (LNR) has significantly better prognostic power than N-status in patients with colorectal cancer, in particular when the number of evaluated lymph nodes (LNs) was insufficient. The aim of this study was to assess the prognostic value of LNR in patients with resected synchronous colorectal liver metastases (SCLMs) and less than 12 examined LNs.

METHODS

A prospectively maintained database of patients with resected SCLMs was queried for patients with less than 12 LNs evaluated at the time of surgery. X-tile software was used to determine the LNR cutoff value able to divide the patients in two subgroups with distinct prognosis. Overall survival (OS) and disease-free survival (DFS) rates were compared by log-rank test. A multivariate Cox regression analysis identified independent prognostic factors.

RESULTS

A cutoff LNR value of 0.22 divided patients into Low-LNR group (35 patients) and High-LNR group (36 patients). Both OS and DFS rates were significantly higher in Low-LNR group than those in High-LNR group. Independent predictors of poor OS were High-LNR (HR: 2.841, 95% CI: 1.480-5.453, p value = 0.002), bilobar SCLMs (HR: 2.253, 95% CI: 1.144-4.437, p value = 0.019) and lack of adjuvant chemotherapy (HR: 2.702, 95% CI: 1.448-5.043, p value = 0.002), while the only independent predictor of poor DFS was High-LNR (HR: 2.531, 95% CI: 1.259-5.090, p value = 0.009).

CONCLUSIONS

LNR > 0.22 was independently associated with poor OS and DFS in patients with resected SCLMs and less than 12 evaluated LNs.

Pathological Features and Prognostication in Colorectal Cancer

The prognostication of colorectal cancer (CRC) has traditionally relied on staging as defined by the Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) TNM staging classifications. However, clinically, there appears to be differences in survival patterns independent of stage, suggesting a complex interaction of stage, pathological features, and biomarkers playing a role in guiding prognosis, risk stratification, and guiding neoadjuvant and adjuvant therapies. Histological features such as tumour budding, perineural invasion, apical lymph node involvement, lymph node yield, lymph node ratio, and molecular features such as MSI, KRAS, BRAF, and CDX2 may assist in prognostication and optimising adjuvant treatment. This study provides a comprehensive review of the pathological features and biomarkers that are important in the prognostication and treatment of CRC. We review the importance of pathological features and biomarkers that may be important in colorectal cancer based on the current evidence in the literature.

Screening and validation of a novel T stage-lymph node ratio classification for operable colon cancer

BACKGROUND

Lymph node ratio (LNR) has advantages in predicting prognosis compared with American Joint Committee on Cancer (AJCC) pathological N stage. However, the prognostic value of a novel T stage-lymph node ratio (TLNR) classification for colon cancer combining LNR and pathological primary tumor stage (T stage) is currently unknown.

METHODS

We included 62,294 patients with stage I-III colon cancer from the Surveillance, Epidemiology, and End Results Program as a training cohort. External validation was performed in 3,327 additional patients. A novel LNR stage was established and combined with T stage in a novel TLNR classification. Patients with similar survival were grouped according to T and LNR stages, with T1LNR1 as a reference.

RESULTS

We developed a novel TLNR classification as follows: stages I (T1LNR1-2, T1LNR4), IIA (T1LNR3, T2LNR1-2, T3LNR1), IIB (T1LNR5, T2LNR3-4, T3LNR2, T4aLNR1), IIC (T2LNR5, T3LNR3-4, T4aLNR2, T4bLNR1), IIIA (T3LNR5, T4aLNR3-4, T4bLNR2), IIIB (T4aLNR5, T4bLNR3-4), and IIIC (T4bLNR5). In the training cohort, the novel TLNR classification had better prognostic discrimination (area under receiver operating characteristic curve, 0.621 vs. 0.608, two-sided P<0.001), superior model-fitting ability for predicting overall survival (Akaike information criteria, 561,129 vs. 562,052), and better net benefits compared with the AJCC 8th tumor/node/metastasis classification. Similar results were found in the validation cohort for predicting both overall and disease-free survival.

CONCLUSIONS

This novel TLNR classification may provide better prognostic discrimination, model-fitting ability, and net benefits than the AJCC 8th TNM classification, for potentially better stratification of patients with operable stage I-III colon cancer; however, further studies are required to validate the novel TLNR classification.

New Nodal Staging for Primary Pancreatic Neuroendocrine Tumors: A Multi-institutional and National Data Analysis

OBJECTIVE

To determine the prognostic role of metastatic lymph node (LN) number and the minimal number of LNs for optimal staging of patients with pancreatic neuroendocrine tumors (pNETs).

BACKGROUND

Prognosis relative to number of LN metastasis (LNM), and minimal number of LNs needed to evaluate for accurate staging, have been poorly defined for pNETs.

METHODS

Number of LNM and total number of LN evaluated (TNLE) were assessed relative to recurrence-free survival (RFS) and overall survival (OS) in a multi-institutional database. External validation was performed using Surveillance, Epidemiology and End Results (SEER) registry.

RESULTS

Among 854 patients who underwent resection, 233 (27.3%) had at least 1 LNM. Patients with 1, 2, or 3 LNM had a comparable worse RFS versus patients with no nodal metastasis (5-year RFS, 1 LNM 65.6%, 2 LNM 68.2%, 3 LNM 63.2% vs 0 LNM 82.6%; all P < 0.001). In contrast, patients with ≥4 LNM (proposed N2) had a worse RFS versus patients who either had 1 to 3 LNM (proposed N1) or node-negative disease (5-year RFS, ≥4 LNM 43.5% vs 1-3 LNM 66.3%, 0 LNM 82.6%; all P < 0.05) [C-statistics area under the curve (AUC) 0.650]. TNLE ≥8 had the highest discriminatory power relative to RFS (AUC 0.713) and OS (AUC 0.726) among patients who had 1 to 3 LNM, and patients who had ≥4 LNM in the multi-institutional and SEER database (n = 2764).

CONCLUSIONS

Regional lymphadenectomy of at least 8 lymph nodes was necessary to stage patients accurately. The proposed nodal staging of N0, N1, and N2 optimally staged patients.

Re-appraising the role of lymph node status in predicting survival in resected distal cholangiocarcinoma - A meta-analysis and systematic review

This systematic review and meta-analysis aimed to confirm the prognostic value of lymph node ratio (LNR), and determine an optimal LNR cut-off for overall survival (OS) in patients with distal cholangiocarcinoma (DCC) undergoing curative surgery. We additionally aimed to provide a consolidated review of current evidence regarding prognostic significance of positive lymph node count (PLNC) and total lymph node count (TLNC). A systematic search of PubMed, EMBASE and Cochrane Library was conducted from inception to October 2020. Studies were included into meta-analysis if there was histological diagnosis, curative surgery, restriction to DCC and relevant LNR results. Quality assessment was performed using the Newcastle Ottawa Scale. Findings for 1228 patients were pooled across 6 studies. Meta-analysis delineated a dose-effect gradient in which higher LNR cut-offs correlated with larger pooled hazard ratios: 0<LNR<0.2 (HR 1.54; 95% CI 1.08-2.20; p = 0.02), LNR>0.2 (HR 3.26; 95% CI 2.07-5.13; p < 0.00001) and LNR>0.4 (HR 3.59; 95% CI 2.31-5.58; p < 0.00001) when compared against a control group of LNR = 0. LNR of 0.2 (HR 2.12; 95% CI: 1.57-2.86; p < 0.0001) was found to be a significant and ideal cut-off for prognostication of poorer OS. A review of current literature reveals an ongoing debate regarding the comparative prognostic value of differing PLNC cut-offs (0/1/3 versus 0/1/4). TLNC of 10-13 is widely reported to be the minimum necessary to ensure improved long term outcomes. PLNC and LNR are strong prognostic factors for OS in DCC. An ideal LNR cut-off of 0.2 is most significantly associated with poorer OS.

Metastatic lymph node ratio as a better prognostic tool than the TNM system in colorectal cancer

Background: The minimum number of lymph nodes that should be evaluated in colon cancer to adequately categorize lymph node status is still controversial. The lymph node ratio (LNR) may be a better prognostic indicator. Materials & methods: We studied 1065 patients treated from 1 January 2000 to 31 August 2012. Results: Significant differences in survival were detected according to regional lymph nodes (pN) (p < 0.001) and LNR (p < 0.001). LRN and pN are independent prognostic factors. Spearman correlation analysis showed a significant correlation between the total number of dissected lymph nodes and pN (rs = 0.167; p < 0.001), but the total number of dissected lymph nodes is not significantly correlated with LNR (rs = -0.019; p = 0.550). Interpretation: In this study, LNR seems to demonstrate a superior prognostic value compared with the pN categories, in part due to its greater independence regarding the extent of lymphadenectomy.

Evaluation of prognostic factors and clinicopathological patterns of recurrence after curative surgery for colorectal cancer

BACKGROUND

Colorectal cancer is a common tumor with a quite high-related mortality. Despite the used curative treatments, patients will develop cancer recurrence in up to 50% of the cases and/or other primary neoplasms. Although most of the recurrences are discovered within 3 years from the first treatment, a small percentage is found after 5 years. The early detection of recurrence is crucial to allow further therapies improving patients’ survival. Several follow-up programs have been developed but the optimal one is far from being established.

AIM

To evaluation of potential prognostic factors for timing and patterns of recurrence in order to plan tailored follow-up programs.

METHODS

Perioperative and long-term data of all consecutive patients surgically treated with curative intent, from January 2006 to June 2009, for colorectal adenocar-cinoma, were retrospectively reviewed to find potential prognostic factors associated with: (1) Recurrence incidence; (2) Incidence of an early (within 3 years from surgery) or late recurrence; and (3) Different sites of recurrence. In addition, the incidence of other primary neoplasms has been evaluated in a cohort of patients with a minimum potential follow-up of 10 years.

RESULTS

Our study included 234 patients. The median follow-up period has been 119 ± 46.2 mo. The recurrence rate has been 25.6%. Patients with a higher chance to develop recurrence had also the following characteristics: Higher levels of preoperative glycemia and carcinoembryonic antigen, highest anaesthesiologists Score score, occlusion, received a complex operation performed with an open technique, after a longer hospital stay, and showed advanced tumors. The independent prognostic factors for recurrence were the hospital stay, N stage 2, and M stage 1 (multivariate analysis). Younger ages were significantly associated with an early recurrence onset. Patients that received intermediate colectomies or segmental resections, having an N stage 2 or American Joint Committee on Cancer stage 3 tumors were also associated with a higher risk of liver recurrence, while metastatic diseases at diagnosis were linked with local recurrence. Neoadjuvant treatments showed lung recurrence. Finally, bigger tumors and higher lymph node ratio were associated with peritoneal recurrence (marginally significant). Thirty patients developed a second malignancy during the follow-up time.

CONCLUSION

Several prognostic factors should be considered for tailored follow-up programs, eventually, beyond 5 years from the first treatment.

Complete mesocolic excision in minimally invasive surgery of colonic cancer: do we need the robot?

Background

Robotic surgery offers favorable prerequisites for complex minimally invasive surgeries which are delivered by higher degrees of freedom, improved instrument stability, and a perfect visualization in 3D which is fully surgeon controlled. In this article we aim to assess its impact on complete mesocolic excision (CME) in colon cancer and to answer the question of whether the current evidence expresses a need for robotic surgery for this indication.

Methods

Retrospective analysis and review of the current literature on complete mesocolic excision for colon cancer comparing the outcome after open, laparoscopic, and robotic approaches.

Results

Complete mesocolic excision results in improved disease-free survival and reduced local recurrence, but turns out to be complex and prone to complications. Introduced in open surgery, the transfer to minimally invasive surgery resulted in comparable results, however, with high conversion rates. In comparison, robotic surgery shows a reduced conversion rate and a tendency toward higher lymph node yield. Data, however, are insufficient and no high-quality studies have been published to date. Almost no oncologic follow-up data are available in the literature.

Conclusion

The current data do not allow for a reliable conclusion on the need of robotic surgery for CME, but show results which hypothesize an equivalence if not superiority to laparoscopy. Due to recently published technical improvements for robotic CME and supplementary features of this method, we suppose that this approach will gain in importance in the future.

Selecting the number of categories of the lymph node ratio in cancer research: A bootstrap-based hypothesis test

The high impact of the lymph node ratio as a prognostic factor is widely established in colorectal cancer, and is being used as a categorized predictor variable in several studies. However, the cut-off points as well as the number of categories considered differ considerably in the literature. Motivated by the need to obtain the best categorization of the lymph node ratio as a predictor of mortality in colorectal cancer patients, we propose a method to select the best number of categories for a continuous variable in a logistic regression framework. Thus, to this end, we propose a bootstrap-based hypothesis test, together with a new estimation algorithm for the optimal location of the cut-off points called BackAddFor, which is an updated version of the previously proposed AddFor algorithm. The performance of the hypothesis test was evaluated by means of a simulation study, under different scenarios, yielding type I errors close to the nominal errors and good power values whenever a meaningful difference in terms of prediction ability existed. Finally, the methodology proposed was applied to the CCR-CARESS study where the lymph node ratio was included as a predictor of five-year mortality, resulting in the selection of three categories.

Prognostic Values of Preoperative Inflammatory and Nutritional Markers for Colorectal Cancer

Background

Increasing evidence indicates that inflammation and nutritional status are associated with survival outcomes in patients with colorectal cancer (CRC). This study aimed to investigate the prognostic values of preoperative inflammatory and nutritional factors and develop a prognostic model individually predicting overall survival (OS) and disease-free survival (DFS) in patients with CRC.

Methods

We retrospectively collected data on patients with CRC who underwent radical surgery. Independent prognostic inflammatory and nutritional markers were identified and novel prognostic models were developed incorporating the identified factors. The discriminative ability and model-fitting performance were evaluated by receiver operating characteristic curves and Akaike information criteria. Clinical usefulness was assessed by decision curve analysis.

Results

A total of 400 eligible patients were identified. Multivariate analysis identified pN stage, tumor differentiation grade, neutrophil count, and body mass index as independent prognostic factors for OS, and pN stage, tumor differentiation grade, neutrophil count, neutrophil-lymphocyte ratio, and serum albumin as prognostic factors for DFS. The combined inflammatory and nutritional prognostic model showed better discriminative ability, model-fitting performance, and net benefits than the inflammatory and nutritional models alone, and the American Joint Committee on Cancer (AJCC) 8th TNM classification for predicting OS and DFS.

Conclusion

Preoperative nutritional and inflammatory factors have significant prognostic value in patients with CRC. A novel prognostic model incorporating preoperative inflammatory and nutritional markers provides better prognostic performance than the AJCC 8th TNM classification. A novel nomogram incorporating preoperative inflammatory and nutritional markers can individually predict OS and DFS in patients with CRC.

Impact of Anatomic Extent of Nodal Metastasis on Adjuvant Chemotherapy Outcomes in Stage III Colon Cancer

BACKGROUND

An oxaliplatin-based chemotherapy regimen improves the survival outcomes of patients with stage III colon cancer. However, its complications are well-known.

OBJECTIVE

The purpose of this study was to distinguish between the survival outcomes of patients who underwent curative resection for stage III colon cancer with oxaliplatin chemotherapy and those who underwent such resection without oxaliplatin chemotherapy.

DESIGN

This was a retrospective analytical study based on prospectively collected data.

SETTINGS

This study used data on patients who underwent surgery at our hospital between January 2010 and December 2014.

PATIENTS

A cohort of 254 consecutive patients who underwent curative resection for stage III colon cancer was included in this study. The patients were divided into 2 groups: patients with isolated pericolic lymph node metastasis (n = 175) and those with extrapericolic lymph node metastasis (n = 79).

MAIN OUTCOME MEASURES

Clinicopathologic features and 3-year survival outcomes were analyzed with and without oxaliplatin therapy in the pericolic lymph node group.

RESULTS

The pericolic lymph node group showed significantly improved overall survival compared with the extrapericolic lymph node group at a median follow-up of 48.5 months (95.8% vs 77.8%; p < 0.001). In contrast, there was no significant difference in overall survival (99.0% vs 92.0%; p = 0.137) and disease-free survival (89.1% vs 88.2%; p = 0.460) between the oxaliplatin and nonoxaliplatin subgroups of the pericolic lymph node group. Multivariate analysis showed that the administration of oxaliplatin chemotherapy to the pericolic lymph node group did not lead to a significant difference in the overall survival (p = 0.594).

LIMITATIONS

The study was limited by its retrospective design and single institutional data analysis.

CONCLUSIONS

This study suggests that the anatomic extent of metastatic lymph nodes could affect patient prognosis, and the effect of oxaliplatin-based adjuvant chemotherapy may not be prominent in stage III colon cancer with isolated pericolic lymph node metastasis.

Log odds of positive lymph nodes is prognostically equivalent to lymph node ratio in non-metastatic colon cancer

BACKGROUND

Globally, colorectal cancer (CRC) is the third and second leading cancer in men and women respectively with 600,000 deaths per year. Traditionally, clinicians have relied solely on nodal disease involvement, and measurements such as lymph node ratio (LNR; the ratio of metastatic/positive lymph nodes to total number of lymph nodes examined), when determining patient prognosis in CRC. The log odds of positive lymph nodes (LODDS) is a logistic transformation formula that uses pathologic lymph node data to stratify survival differences among patients within a single stage of disease. This formula allows clinicians to identify whether patients with clinically aggressive tumours fall into higher-risk groups regardless of nodal positivity and can potentially guide adjuvant treatment modalities. The aim of this study was to investigate whether LODDS in colon cancer provides better prognostication compared to LNR.

METHODS

A retrospective study of patients on the prospectively maintained Cabrini Monash University Department of Surgery colorectal neoplasia database, incorporating data from hospitals in Melbourne Australia, identified patients entered between January 2010 and March 2016. Association of LODDS and LNR with clinical variables were analysed. Disease-free (DFS) and overall (OS) survival were investigated with Cox regression and Kaplan-Meier survival analyses.

RESULTS

There were 862 treatment episodes identified in the database (402 male, 47%). The median patient age was 73 (range 22-100 years). There were 799 colonic cancers and 63 rectosigmoid cancers. The lymph node yield (LNY) was suboptimal (< 12) in 168 patients (19.5%) (p = 0.05). The 5-year OS for the different LNR groups were 86, 91 and 61% (p < 0.001) for LNR₀ (655 episodes), LNR₁ (128 episodes) and LNR₂ (78 episodes), respectively. For LODDS, they were 85, 91 and 61% (p < 0.001) in LODDS₀ (569 episodes), LODDS₁ (217 episodes) and LODDS₂ (75 episodes) groups (p < 0.001). Overall survival rates were comparable between the LNR and LODDS group and for LNY < 12 and stage III patients when each were sub-grouped by LODDS and LNR.

CONCLUSION

This study has shown for that the prognostic impact of LODDS is comparable to LNR for colon cancer patients. Accordingly, LNR is recommended for prognostication given its ease of calculation.

Survival outcomes following laparoscopic vs open surgery for non-metastatic rectal cancer: a two-center cohort study with propensity score matching

BACKGROUND?>

Laparoscopic surgery for rectal cancer is commonly performed in China. However, compared with open surgery, the effectiveness of laparoscopic surgery, especially the long-term survival, has not been sufficiently proved.

METHODS?>

Data of eligible patients with non-metastatic rectal cancer at Nanfang Hospital of Southern Medical University and Guangdong Provincial Hospital of Chinese Medicine between 2012 and 2014 were retrospectively reviewed. Long-term survival outcomes and short-term surgical safety were analysed with propensity score matching between groups.

RESULTS

Of 430 cases collated from two institutes, 103 matched pairs were analysed after propensity score matching. The estimated blood loss during laparoscopic surgery was significantly less than that during open surgery (P = 0.019) and the operative time and hospital stay were shorter in the laparoscopic group (both P < 0.001). The post-operative complications rate was 9.7% in the laparoscopic group and 10.7% in the open group (P = 0.818). No significant difference was observed between the laparoscopic group and the open group in the 5-year overall survival rate (75.7% vs 80.6%, P = 0.346), 5-year relapse-free survival rate (74.8% vs 76.7%, P = 0.527), or 5-year cancer-specific survival rate (79.6% vs 87.4%, P = 0.219). An elevated carcinoembryonic antigen, <12 harvested lymph nodes, and perineural invasion were independent prognostic factors affecting overall survival and relapse-free survival.

CONCLUSIONS?>

Our findings suggest that open surgery should still be the priority recommendation, but laparoscopic surgery is also an acceptable treatment for non-metastatic rectal cancer.

Significance of lymph node ratio on survival of women with borderline ovarian tumors

PURPOSE

To assess the qualitative and quantitative measures of the effect of pelvic lymph node involvement on survival of women with borderline ovarian tumors (BOTs).

METHODS

This is a retrospective study examining the Surveillance, Epidemiology, and End Results Program between 1988 and 2003. Women with stage T1-3 BOTs who had results of pelvic lymph node status at surgery were included. The effect of lymph node involvement on cause-specific survival (CSS) was evaluated using multivariable analysis with the following approaches: (1) any involvement, (2) involvement of multiple nodes (≥ 2 nodes), and (3) lymph node ratio (LNR), defined as the ratio of the number of tumor-containing lymph nodes to the total number of harvested lymph nodes.

RESULTS

A total of 1524 women were examined for analysis. Median count of sampled nodes was 8 (interquartile range 3-15), and there were 81 (5.3%, 95% confidence interval [CI] 4.2-6.4) women who had lymph node involvement. Median follow-up was 15.8 (interquartile range 13.8-18.9) years, and 83 (5.4%) women died of BOTs. After controlling for age, histology, stage, and tumor size, only LNR remained an independent prognostic factor for decreased CSS (adjusted hazard ratio [HR] per percentage unit 1.015, 95% CI 1.003-1.026, P = 0.014), whereas any involvement (adjusted HR 1.700, 95% CI 0.843-3.430, P = 0.138) and involvement of multiple nodes (adjusted HR 1.644, 95% CI 0.707-3.823, P = 0.249) did not. On cutoff analysis, LNR ≥ 13% had the largest magnitude of significance on multivariable analysis of CSS (adjusted HR 2.399, 95% CI 1.163-4.947, P = 0.018).

CONCLUSION

Our study suggests that high pelvic LNR may be a prognostic factor associated with decreased CSS in women with BOTs.

Screen detection is a survival predictor independent of pathological grade in colorectal cancer. A prospective cohort study

INTRODUCTION

Patients with screened detected colorectal cancer (CRC) have a better survival than patients referred with symptoms. This may be because of cancers being identified in a younger population and at an earlier stage. In this study, we assess whether screened detected CRC has an improved outcome after controlling for key pathological and patient factors known to influence prognosis.

METHOD

This is a cohort study of all CRC patients diagnosed in NHS Grampian. Patients aged 51-75 years old between June 2007 and July 2017 were included. Data were obtained from a prospectively maintained regional pathology database and outcomes from ISD records. All-cause mortality rates at 1 and 5 years were examined. A Cox proportional hazards regression model was used to estimate the effect of screening status, age, gender, Duke stage, tumour location, extramural venous invasion (EMVI) status and lymph node ratio (LNR) on overall survival.

RESULTS

Of 1618 CRC cases, 449 (27.8%) were screened and 1169 (72.2%) were symptomatic. Screened CRC patients had improved survival compared to non-screened CRC at 1 year (88.9% vs 83.9% p < 0.001) and 5-years (42.5% vs 36.2%; p < 0.001). On multivariable analysis of patients who had no neoadjuvant therapy (n = 1272), screening had better survival (HR 0.57; 95% CI 0.44-0.74; p < 0.001). EMVI (HR 2.22; CI 1.76 to 2.79; p < 0.001) and tumour location were found to affect outcome.

CONCLUSION

Patients referred through screening had improved survival compared with symptomatic patients. Further research could be targeted to determine if screened CRC cases are pathologically different to symptomatic cancers or if the screening cohort is inherently more healthy.

"Caudal-to-cranial" plus "artery first" technique with beyond D3 lymph node dissection on the right midline of the superior mesenteric artery for the treatment of right colon cancer: is it more in line with the principle of oncology?

OBJECTIVE

To explore the feasibility and application value of a "caudal-to-cranial" plus "artery first" technique with beyond D3 lymph node dissection on the right midline of the superior mesenteric artery (SMA) for the treatment of right colon cancer METHODS: Clinical data consisting of 168 right colon cancer cases under going laparoscopic D3 radical resection, including 84 cases of "caudal-to-cranial" plus "artery first" technique with beyond D3 lymph node dissection on the right midline of the SMA (CC + SMA group) and 84 cases of conventional medial approach plus dissection around the superior mesenteric vein (MA + SMV group), from January 2017 to March 2018 were retrospectively analyzed. For CC + SMA group, our surgical method was to isolate the mesocolon using a caudal-to-cranial pathway and ligate blood vessels along the midline of the SMA.

RESULTS

The baseline data was not significantly different between the two groups (all p > 0.05). The mean operation time and intraoperative blood loss in the CC + SMA and the MA + SMV groups were 170.04 ± 43.10 versus 172.33 ± 41.84 min and 91.07 ± 55.12 versus 77.38 ± 40.21 ml, respectively, which has no significant difference (p > 0.05). The mean number of total and positive harvested lymph nodes in the two groups were 29.44 ± 5.90 versus 26.21 ± 6.64 (p < 0.05) and 2.57 ± 1.93 versus 2.51 ± 1.05, respectively (p > 0.05). Compared with the MA + SMV group, there was no significant difference in total postoperative complication rate in the CC + SMA group. The time to pull out drainage tube in the CC + SMA group was longer than MA + SMV group (4.05 ± 1.79 versus 3.38 ± 1.99 day; p = 0.022).

CONCLUSION

It is safe and feasible for the "caudal-to-cranial" plus "artery first" technique with beyond D3 lymph node dissection on the right midline of the SMA in right colon cancer. It may have some advantages in the number of lymph nodes dissection, and the long-term prognosis remains to be expected.

Comparison of different lymph node staging schemes in prostate cancer patients with lymph node metastasis

PURPOSE

In addition to standard TNM N staging, lymph node ratio (LNR) and log odds of metastatic lymph node (LODDS) staging methods have been developed for cancer staging. We compared the prognostic performance of the total number of lymph nodes examined (TNLE), number of metastatic lymph node (NMLN), LNR, and LODDS in prostate cancer.

METHODS

Data from 1400 patients diagnosed with prostate cancer between 2004 and 2009 who underwent lymphadenectomy were extracted from the Surveillance Epidemiology and End Results database. Kaplan-Meier methods and multivariable Cox regression analysis were used to evaluate the prognostic value of different lymph node staging schemes in patients with lymph node metastasis.

RESULTS

Univariate analysis showed that age, T stage, radiotherapy history, Gleason score, LNR classification, LODDS classification, and NMLN except TNLE classification were significant prognostic factors for overall survival. In multivariate analysis, LNR classification, LODDS classification, and NMLN but TNLE classification remained significant prognostic factors for overall survival. LNR classification had the highest C-index (0.672; 95% confidence interval [CI]: 0.609-0.734) and the lowest Akaike information criterion (AIC) (4057.018), indicating the best prognostic performance. Scatter plots showed that LODDS increased with increasing LNR, exhibiting a strong overall correlation between these two lymph node staging methods (r² = 0.9072). LNR and LODDS generally increased with increasing NMLN, although the correlation was relatively low.

CONCLUSION

Our results indicate that LNR and LODDS may be better predictors of overall survival than the AJCC/UICC N category in patients undergoing curative surgery for prostate cancer.

Lymph node ratio (LNR) as a complementary staging system to TNM staging in salivary gland cancer

Purpose

The role of lymph node ratio (LNR, ratio of metastatic to examined nodes) in the staging of multiple human malignancies has been reported. We aim to evaluate its value in salivary gland cancer (SGC).

Methods

Records of SGC patients from Surveillance, Epidemiology, and End Results database (SEER, training set, N = 4262) and Fudan University Shanghai Cancer Center (FUSCC, validating set, N = 154) were analyzed for the prognostic value of LNR. Kaplan–Meier survival estimates, the Log-rank χ² test and Cox proportional hazards model were used for univariate and multivariate analysis. Optimal LNR cutoff points were identified by X-tile.

Results

Optimal LNR cutoff points classified patients into four risk groups, R0, R1 (≤ 0.17), R2 (0.17–0.56) and R3 (> 0.56), corresponding to 5-year cause-specific survival in SEER patients of 88.6%, 57.2%, 53.1% and 39.7%, disease-free survival in FUSCC patients of 69.2%, 63.3%, 34.6% and 0%, and disease-specific survival in FUSCC patients of 92.3%, 90.0%, 71.4% and 0%, respectively. Compared with TNM staging, TNM + R staging showed smaller AIC values and higher C-index values in the Cox regression model in both patient sets.

Conclusions

LNR classification should be considered as a complementary system to TNM staging and LNR classification based clinical trials deserve further research.

Electronic supplementary material

The online version of this article (10.1007/s00405-019-05597-0) contains supplementary material, which is available to authorized users.

Development and validation of a novel prognostic score to predict survival in patients with metastatic colorectal cancer: the metastatic colorectal cancer score (mCCS)

AIM

Published prognostic scores for metastatic colorectal cancer (mCRC) are based on data from highly selected patient subgroups with specified first-line treatments and may not be applicable to routine practice. We have therefore developed and validated the metastatic colorectal cancer score (mCCS) to predict overall survival (OS) for patients with mCRC.

METHOD

A total of 1704 patients from the prospective, multicentre cohort study Tumour Registry Colorectal Cancer were separated into learning (n = 796) and validation (n = 908) samples. Using a multivariate Cox regression model, the six-factor mCCS was established.

RESULTS

The six independent prognostic factors for survival are as follows: two or more metastatic sites at the start of first-line treatment, tumour grading ≥ G3 at primary diagnosis, residual tumour classification ≥ R1/unknown, lymph node ratio (of primary tumour) ≥ 0.4, tumour stage ≥ III/unknown at primary diagnosis and KRAS status mutated/unknown. The mCCS clearly separated the learning sample into three risk groups: zero to two factors (low risk), three factors (intermediate risk) and four to six factors (high risk). The prognostic performance of the mCCS was confirmed in the validation sample and additionally stratified a large sample of patients with known (K)RAS mutation status.

CONCLUSION

The novel prognostic score, mCCS, clearly defines three prognostic groups for OS at start of first-line therapy. For oncologists, the mCCS represents a simple and easy-to-apply tool for routine clinical use, as it is based on objective tumour characteristics and can assist with treatment decision-making and communication of the prognosis to patients.

Increased lymph node yield indicates improved survival in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy

PURPOSE

It is recommended for colorectal cancer to harvest at least 12 lymph nodes (LNs) during surgery to avoid understaging of the disease. However, it is still controversial whether it is necessary to harvest from locally advanced rectal cancer (LARC) patients who underwent neoadjuvant chemoradiotherapy (neo-CRT). The impact of lymph node yield (LNY) on prognosis in LARC patients was analyzed.

MATERIALS/METHODS

In total, 495 LARC patients who underwent neo-CRT in 2006-2015 were analyzed. After examining clinicopathological distribution differences between the LNY subgroups (with the threshold of 12), univariate and multivariate Cox survival analyses were performed. Survival plots were obtained from Kaplan-Meier analyses. Similar subgroup analyses were performed according to the tumor regression grade (TRG) and metastatic status of post-operational LNs.

RESULTS

Of the 495 patients, 287 (57.98%) had an LNY of less than 12. Nearly no significant clinicopathological difference was found between the LNY subgroups, including the TRG scores. Multivariate survival analysis demonstrated that at least 12 LNs examined was an independent prognostic feature of good overall survival (OS), disease-free survival (DFS), and distant metastasis free survival (DMFS), but not local recurrence free survival (LRFS). However, in the subgroup analyses, no association was found between LNY and prognosis in patients with good TRG scores (0-1) or negative LNs.

CONCLUSIONS

For LARC patients treated with neo-CRT, an LNY of at least 12 indicated an improved survival. Decreased LNY was not related to better tumor regression. It suggests that a sufficiently high LNY is still required, especially in those with a potentially poor tumor response.

Feasibility and efficacy of laparoscopic radical right hemicolectomy with complete mesocolic excision using an 'artery-first' approach

Background

According to previous guidelines, the lymph nodes around the right side of the superior mesenteric artery (SMA) should be dissected and removed en bloc. However, due to the technical challenge and the risk of complications, most surgeons perform the dissection along the axis of the superior mesenteric vein (SMV). Herein, we described an ‘artery-first’ approach for laparoscopic radical extended right hemicolectomy with complete mesocolic excision (CME).

Methods

A total of 22 cases were collected from January to October 2016. The right side of the SMA and SMV were exposed and separated, and the No. 203, No. 213 and No. 223 lymph nodes were dissected en bloc. Toldt’s fascia was dissected and expanded laterally to the ascending colon, cranial to the pancreas head. The caudal root of the mesentery and lateral attachments of the ascending colon were completely mobilized.

Results

There were 9 male and 13 female patients, with a mean age of 63.1 (range, 39–83) years and the mean body mass index was 24.6 (range, 18.3–37.7) kg/m². The mean operative time was 192.5 (range, 145–240) minutes and the mean intra-operative blood loss was 55.0 (range, 10–300) ml. The mean number of harvested lymph nodes was 27.0 (range, 13–55) and the time to flatus and hospital stay were 35.0 (range, 26–120) hours and 7.5 (range, 5–20) days, respectively. Minor complications occurred in two patients and no post-operative death was observed.

Conclusions

The preliminary results suggest that the reported approach may be a feasible and safe procedure that is more in accordance with the principles of CME.

Comparison of Different Lymph Node Staging Systems in Patients With Resectable Colorectal Cancer

Background and Objectives: Currently, the United States Joint Commission on Cancer (AJCC) N staging, lymph node positive rate (LNR), and log odds of positive lymph nodes (LODDS) are the main lymph node (LN) staging systems. However, the type of LN staging system that is more accurate in terms of prognostic performance remains controversial. We compared the prognostic accuracy of the three staging systems in patients with CRC and determine the best choice for clinical applications. Methods: From the Surveillance, Epidemiology, and End Results (SEER) database, 56,747 patients were identified who were diagnosed with CRC between 2004 and 2013. Akaike's Information Criterion (AIC) and Harrell's Consistency Index (c-index) were used to assess the relative discriminative abilities of different LN staging systems. Results: In 56,747 patients, when using classification cut-off values for evaluation, the LNR of Rosenberg et al. showed significantly better predictive power, especially when the number of dissected lymph nodes (NDLN) were insufficient. When analyzed as a continuous variable, the LODDS staging system performed the best and was not affected by the NDLN. Conclusions: We suggest that the LNR of Rosenberg et al. should be introduced into the AJCC system as a supplement when the NDLN is insufficient until the optimal LODDS cut-off values are calculated.

The Prognostic Impact of the Metastatic Lymph Nodes Ratio in Colorectal Cancer

Background: This study was designed to validate the prognostic significance of the ratio of positive to examined lymph nodes (LNR) in patients with colorectal cancer. Methods: 218,314 patients from the SEER database and 1,811 patients from the three independent multicenter were included in this study. The patients were divided into 5 groups on a basis of previous published LNR: LNR0, patients with no metastatic lymph nodes; LNR1, patients with the LNR between 0.1 and 0.17; LNR2, patients with the LNR between 0.18 and 0.41; LNR3, patients with the LNR between 0.42 and 0.69; LNR4, patients with the LNR >0.7. The 5-year OS and CSS rate were estimated using Kaplan-Meier method and the survival difference was tested using log-rank test. Multivariate Cox analysis was used to further assess the influence of the LNR on patients' outcome. Results: The 5-year OS rate of patients within LNR0 to LNR4 group was 71.2, 55.8, 39.3, 22.6, and 14.6%, respectively (p < 0.001) in the SEER database. While the 5-year OS rate of those with LNR0 to LNR4 was 75.2, 66.1, 48.0, 34.0, and 17.7%, respectively (p < 0.001) in the international multicenter cohort. In the multivariate analysis, LNR was demonstrated to be a strong prognostic factor in patients with < 12 and ≥12 metastatic lymph nodes. Furthermore, the LNR had a similar impact on the patients' prognosis in colon cancer and rectal cancer. Conclusion: The LNR allowed better prognostic stratification than the positive node (pN) in patients with colorectal cancer and the cut-off values were well validated.

Prognostic Significance of the Lymph Node Ratio in Surgical Patients With Distal Cholangiocarcinoma

BACKGROUND

The aim of this study was to compare the prognostic impact of the lymph node ratio (LNR) versus positive lymph node count (PLNC) in patients who had undergone resection for distal cholangiocarcinoma.

METHODS

We identified 448 patients with resected distal cholangiocarcinoma from the Surveillance, Epidemiology, and End Results database. The X-Tile program was used to calculate the cutoff values for the LNR and PLNC that discriminate survival. The overall survival and cancer-specific survival rates were calculated. Relationships between clinicopathological factors and patient survival were assessed using univariate and multivariate analyses.

RESULTS

The optimal cutoff values for the LNR and PLNC were 0.45 and 3, respectively. Univariate analysis revealed that tumor size, the American Joint Committee on Cancer stage, T stage, the LNR and PLNC were significantly associated with prognosis (P < 0.05). Multivariate analysis demonstrated that the LNR, T stage, and tumor size were independent prognostic factors for cancer-specific and overall survival, whereas PLNC was not. In the subgroup of patients with positive lymph nodes, patients with an LNR of greater than 0.45 had significantly worse cancer-specific survival (hazard ratio, 2.418; 95% confidence interval, 1.588 to 3.682; P < 0.001) and overall survival (hazard ratio, 2.149; 95% CI, 1.421 to 3.249; P < 0.001) than those with an LNR of 0.45 or less.

CONCLUSIONS

The LNR was a better predictor of long-term prognosis than PLNC in patients with distal cholangiocarcinoma.

Acetone clearance of mesocolic or mesorectal fat increases lymph node yield and may improve detection of high-risk Stage II colorectal cancer patients

AIM

Lymph node (LN) status is key to determining the need for adjuvant therapy in colorectal cancer (CRC) and for disease which has progressed to Stage II (T3-T4, N0, M0). A yield of fewer than 12 LNs is considered a risk factor similar to high-grade histology and vascular, lymphatic and perineural invasion. The aim of this retrospective study was to investigate the effect of acetone fat clearance of the mesocolon or mesorectum on LN yield and the identification of patients with high-risk Stage II CRC.

METHOD

After conventional LN retrieval, fatty tissue derived from the mesocolon or mesorectum of 80 CRC specimens was incubated in acetone for 24 h. A second dissection was then performed by a trained technician. The total number of LNs as well as tumour involvement (LNpositive and LNnegative) were assessed at each stage. In addition, LN morphology was assessed and clinicopathological data were extracted from existing pathology reports.

RESULTS

Eighty CRC specimens were available for study. 1548 (94%) LN were negative and 96 (6%) were positive. The median (range) LN yield per specimen was 12 (3-41) LN increasing to 18 (4-48) LN after fat clearance (P < 0.001). After fat clearance, 534 additional LNs were identified in 75 (94%) of the specimens, and all but 10 were negative. The pN stage did not change in six patients who were found to be LN positive after fat clearance. However, the number of high-risk Stage II CRC patients decreased from 11 to 7. Although important for these patients, this downstaging did not reach statistical significance (P = 0.125).

CONCLUSION

Acetone clearance of mesocolic or mesorectal fat increases median LN yield and may in a larger study decrease the number of patients classified as having high-risk Stage II CRC.

Lymph node ratio is inferior to pN-stage in predicting outcome in colon cancer patients with high numbers of analyzed lymph nodes

Background

The lymph node ratio (LNR), i.e. the number of positive lymph nodes (LN) divided by the total number of analyzed LN, has been described as a strong outcome predictor in node-positive colon cancer patients. However, most published analyses are constrained by relatively low numbers of analyzed LN. Therefore, the objective of the present study was to evaluate the prognostic impact of LNR in colon cancer patients with high numbers of analyzed LN.

Methods

One hundred sixty-six colon cancer patients underwent open colon resection. All node-positive patients were analyzed for this study. The number of analyzed LN, of positive LN, the disease-free (DFS) and overall survival (OS) time were prospectively recorded. Patients were dichotomously allocated to a high or a low LNR-group, respectively, with the median LNR (0.125) as a cut-off value. Median follow-up was 34.3 months.

Results

Fifty-eight patients (34.9%) were node-positive. The median number of analyzed LN was 23 (range 8–54). DFS and OS were significantly shorter in pN2 vs pN1 patients (p < 0.001, and p = 0.001, respectively), and in LNR high vs low patients (p = 0.032, and p = 0.034, respectively). pN2 (vs pN1) disease showed hazard ratios (HR) of 6.2 (p < 0.001), and 6.8 (p < 0.005; for DFS and OS, respectively), while LNR high (vs low) showed HR of 3.0 (p =0.041), and 4.5 (p = 0.054).

Conclusions

LNR is a reasonable outcome predictor in node-positive colon cancer patients. However, LNR is inferior to pN-stage in predicting survival in patients with high number of harvested lymph nodes.

Electronic supplementary material

The online version of this article (10.1186/s12893-018-0417-0) contains supplementary material, which is available to authorized users.

Evaluation on prognostic efficacy of lymph nodes ratio (LNR) and log odds of positive lymph nodes (LODDS) in complicated colon cancer: the first study in emergency surgery

BACKGROUND

Lymph node involvement is one of the most important prognostic factors in colon cancer. Twelve is considered the minimum number of lymph nodes necessary to retain reliable tumour staging, but several factors can potentially influence the lymph node harvesting. Emergent surgery for complicated colon cancer (perforation, occlusion, bleeding) could represent an obstacle to reach the benchmark of 12 nodes with an accurate lymphadenectomy. So, an efficient classification system of lymphatic involvement is crucial to define the prognosis, the indication to adjuvant therapy and the follow-up. This is the first study with the aim to evaluate the efficacy of lymph nodes ratio (LNR) and log odds of positive lymph nodes (LODDS) in the prognostic assessment of patients who undergo to urgent surgery for complicated colonic cancer.

METHODS

This is a retrospective study carried out on patients who underwent urgent colonic resection for complicated cancer (occlusion, perforation, bleeding, sepsis). We collected clinical, pathological and follow-up data of 320 patients. Two hundred two patients met the inclusion criteria and were distributed into three groups according to parameter N of TNM, LNR and LODDS. Survival analysis was performed by Kaplan-Meier curves, investigating both overall survival (OS) and disease-free survival (DFS).

RESULTS

The median number of harvested lymph nodes was 17. In 78.71% (n = 159) of cases, at least 12 lymph nodes were examined. Regarding OS, significant differences from survival curves emerged for ASA score, surgical indication, tumour grading, T parameter, tumour stage, N parameter, LNR and LODDS. In multivariate analysis, only LODDS was found to be an independent prognostic factor. Concerning DFS, we found significant differences between survival curves of sex, surgical indication, T parameter, tumour stage, N parameter, LNR and LODDS, but none of these confirmed its prognostic power in multivariate analysis.

CONCLUSIONS

We found that N, LNR and LODDS are all related to 5-year OS and DFS with statistical significance, but only LODDS was found to be an independent prognostic factor for OS in multivariate analysis.

ARHGEF7 promotes metastasis of colorectal adenocarcinoma by regulating the motility of cancer cells

Previous studies have shown that Rho guanine nucleotide exchange factor 7 (ARHGEF7) is implicated in cytoskeleton remodelling, which is important for cell motility and invasiveness, and exhibits frequent high-level genetic amplification in metastatic lesions of colorectal adenocarcinoma. Therefore, it was hypothesized that ARHGEF7 may be involved in the metastasis of colorectal adenocarcinoma. In the present study, it was demonstrated that the expression level of ARHGEF7 was significantly upregulated in colorectal adenocarcinoma tumor tissues compared with matched nontumorous tissues, and its expression level correlated with colorectal adenocarcinoma metastasis. In vitro assays showed that the overexpression of ARHGEF7 in CRC cells significantly enhanced cell migration and invasion, whereas the knockdown of ARHGEF7 in colorectal adenocarcinoma cells significantly decreased cell migration and invasion. In vivo assays showed that the overexpression of ARHGEF7 in CRC cells facilitated tumor metastasis, whereas the knockdown of ARHGEF7 in CRC cells significantly inhibited tumor metastasis. Furthermore, it was demonstrated that ARHGEF7 promoted cell motility by regulating the actin cytoskeleton. Finally, according to ReMARK guidelines for reporting prognostic biomarkers in cancer, it was found that a high expression of ARHGEF7 was significantly correlated with lymph node, mesenteric and distant metastasis. Patients with colorectal adenocarcinoma with a high expression of ARHGEF7 had shorter disease-free survival (DFS) and shorter overall survival (OS) rates, compared with those with a low expression of ARHGEF7, as determined by the Kaplan-Meier method with a log-rank test. Cox regression analysis showed that a high expression of ARHGEF7 was an independent risk factor for DFS and OS rates in colorectal adenocarcinoma.

Session 1: Colon cancer - 10 years behind the rectum

The improvements in surgical technique brought about by the widespread adoption of total mesorectal excision plane dissection in rectal cancer has substantially improved survival and recurrence rates from this disease. For the first time in 50 years, the outcomes in rectal cancer have overtaken those of colon cancer. Professor Madoff's overview lecture and the experts' round table discussion address whether applying the surgical principles already achieved in rectal cancer can meet with similar success in colon cancer, how this can be achieved and the challenges we face.

Role of "Second Look" Lymph Node Search in Harvesting Optimal Number of Lymph Nodes for Staging of Colorectal Carcinoma

As with other malignancies, lymph node metastasis is an important staging element and prognostic factor in colorectal carcinomas. The number of involved lymph nodes is directly related to decreased 5-year overall survival for all pT stages according to United States Surveillance, Epidemiology, and End Results (SEER) cancer registry database. The National Quality Forum specifies that the presence of at least 12 lymph nodes in a surgical resection is one of the key quality measures for the evaluation of colorectal cancer. Therefore, the harvesting of a minimum of twelve lymph nodes is the most widely accepted standard for evaluating colorectal cancer. Since this is an accepted quality standard, a second attempt at lymph node dissection in the gross specimen is often performed when the initial lymph node count is less than 12, incurring a delay in reporting and additional expense. However, this is an arbitrary number and not based on any hard scientific evidence. We decided to investigate whether the additional effort and expense of submitting additional lymph nodes had any effect on pathologic lymph node staging (pN). We identified a total of 99 colectomies for colorectal cancer in which the prosector subsequently submitted additional lymph nodes following initial review. The mean lymph node count increased from 8.3 ± 7.5 on initial search to 14.6 ± 8.0 following submission of additional sections. The number of cases meeting the target of 12 lymph nodes increased from 14 to 69. Examination of the additional lymph nodes resulted in pathologic upstaging (pN) of five cases. Gross reexamination and submission of additional lymph nodes may provide more accurate staging in a limited number of cases. Whether exhaustive submission of mesenteric fat or fat-clearing methods is justified will need to be further investigated.

Novel lymph node ratio predicts prognosis of colorectal cancer patients after radical surgery when tumor deposits are counted as positive lymph nodes: a retrospective multicenter study

The lymph node ratio (LNR), defined as the relation of tumor-infiltrated to resected lymph nodes, has been identified as an independent prognostic factor for colorectal cancer (CRC) after radical surgery. Recently, new guidelines propose counting tumor deposits (TDs) as positive lymph nodes (pLNs). The aim of this study was to investigate whether a novel LNR (nLNR) that considers TDs as pLNs can be used to accurately predict the long-term outcome of CRC patients. In this multicenter retrospective study, clinicopathological and outcome data from 2,051 stage III CRC patients who underwent R0 resection were collected between January 2004 and December 2011. Disease-free survival (DFS) and overall survival (OS) according to the nLNR category were analyzed using Kaplan-Meier survival curves. Univariate and multivariate analyses were performed to determine significant prognostic factors, and ROC curves were computed to measure the predictive capacity of the nLNR category. The 5-year DFS rates of nLNR1-4 were 68.3%, 48.4%, 33.3% and 16.5%, respectively (P<0.0001), and the 5-year OS rate of nLNR1-4 were 71.8%, 60.1%, 42.7% and 21.8%, respectively (P<0.0001). The area of under curve (AUC) of the nLNR was 0.686 (95% CI 0.663-0.710) and 0.672 (95% CI 0.648-0.697) for predicting DFS and OS. Our results demonstrate that the nLNR predicted long-term outcomes better than the LNR, npN and pN, using the cutoff points 0.250, 0.500 and 0.750.

Laparoscopic surgery for locally advanced T4 colon cancer: the long-term outcomes and prognostic factors

Purpose

For locally advanced pathological T4 (pT4) colon cancer, the safety and feasibility of laparoscopic procedures remain controversial. Therefore, this study aimed to assess short-term and long-term outcomes and to identify the prognostic factors in laparoscopic surgery for pT4 colon cancer.

Methods

The study group included 130 patients who underwent laparoscopic radical resection for pT4 colon and rectosigmoid cancer from January 2004 through December 2012. The short-term outcomes, long-term outcomes, and prognostic factors in pT4 colon cancer were analyzed.

Results

The median operative time was 205 min, with a median blood loss of 10 ml. The conversion rate was 3.8%, and 13 patients (10.0%) had postoperative complications. The radial resection margin was positive in 1 patient (0.8%). The median follow-up time was 73 months. The 5-year overall survival (OS) and recurrence-free survival (RFS) were 77.2 and 63.5%, respectively. On a multivariate analysis, a male sex [hazard ratio (HR) 3.09, p < 0.001], lymph node ratio ≥ 0.06 (HR 2.35, p = 0.021), tumor diameter < 38 mm (HR 2.57, p = 0.007), and right-sided colon cancer (HR 2.11, p = 0.047) were significantly related to a poor OS.

Conclusions

These results suggest that laparoscopic surgery for pT4 colon cancer is safe and feasible, and the oncological outcomes are acceptable. Based on the present findings, select patients with locally advanced colon cancer should not be excluded from laparoscopic surgery.

Laparoscopic modified mesocolic excision with central vascular ligation in right-sided colon cancer shows better short- and long-term outcomes compared with the open approach in propensity score analysis

Background

The introduction of complete mesocolic excision (CME) with central vessel ligation (CVL) for right-sided colon cancer has improved oncologic outcomes. However, there is controversy over the oncologic safety of laparoscopic CME with CVL. This study compared short-term and long-term oncologic outcomes between laparoscopic and open modified CME (mCME) with CVL in patients with right-sided colon cancer.

Methods

We enrolled 1239 patients who underwent open mCME with CVL and 1010 patients treated by a laparoscopic approach for right-side colon cancer between 2000 and 2013 and used 1:1 propensity score matching to adjust for potential baseline confounders between two groups.

Results

After propensity score matching, 683 patients who underwent open mCME with CVL were compared with 683 patients treated with a laparoscopic approach. There were no significant differences between these groups in age, sex, ASA score, TNM stage, tumor size, lymphovascular invasion, and perineural invasion. Comparison of open and laparoscopic mCME groups showed no significant difference in postoperative morbidity (21.4 vs. 18.3%, p = 0.175) and mortality (0.1 vs. 0%, p = 1.000). The laparoscopic mCME group showed shorter length of hospital stay. The 5-year overall survival rate was 83.7% in the open group and 94.7% in the laparoscopic group (p < 0.001). The laparoscopic group also showed a significantly better 5-year disease-free survival rate (82.7 vs. 88.7%, p = 0.009) and 5-year disease-specific survival rate (83.7 vs. 94.7%, p < 0.001).

Conclusion

Laparoscopic modified mesocolic excision with central vascular ligation is a safe and feasible approach with better short-term recovery profiles and potential oncologic benefits than the open approach for right-sided colon cancer.

Association of primary tumor lymph node ratio with burden of liver metastases and survival in stage IV colorectal cancer

BACKGROUND

The primary objective of our study was to assess the association of primary tumor lymph node ratio (LNR) in stage IV colorectal adenocarcinomas (CRC) with overall survival (OS) and the extent of metastatic disease in the liver.

METHODS

We analyzed data on 53 stage IV CRC patients who underwent surgical resection of the primary tumor. The median LNR of 0.25 was used to stratify patients into high LNR (H-LNR) and low LNR (L-LNR) groups. Statistical comparison was performed using chi square test and multiple regression models. OS was calculated using the Kaplan-Meier (KM) method while cox regression was used for multivariate analysis.

RESULTS

H-LNR status was associated with the presence of >3 liver metastases (LM) [odds ratio (OR): 2.43, P=0.047] and bilobar LM (OR: 3.94, P=0.039). The OS in H-LNR patients was significantly worse in the entire cohort compared to L-LNR (9% vs. 34% at 3 years, P=0.027). The 5-year OS in patients undergoing liver resection for LM was also significantly worse in the H-LNR group (0% vs. 37%, P=0.013). LNR was independently associated with survival on multivariate analysis [HR: 2.63; 95% confidence intervals (CI), 1.13-6.14; P=0.025].

CONCLUSIONS

In stage IV CRC, LNR is associated with the extent of hepatic tumor burden and was an independent predictor of survival in patients undergoing liver resection.

Log odds of positive lymph nodes is superior to the number- and ratio-based lymph node classification systems for colorectal cancer patients undergoing curative (R0) resection

The metastatic lymph node status (N classification) is an important prognostic factor for patients with colorectal cancer (CRC). The aim of the present study was to evaluate and compare the prognostic assessment of three different lymph node staging methods, namely standard lymph node (pN) staging, metastatic lymph node ratio (LNR) and log odds of positive lymph nodes (LODDS) in CRC patients who undergo curative resection (R0). Data were retrospectively collected from 192 patients who had undergone R0 resection. Kaplan-Meier survival curves, Cox proportional hazards model and accuracy of the three methods (pN, LNR and LODDS) were compared to evaluate the prognostic effect. Univariate analysis demonstrated that pN, LNR and LODDS were all significantly correlated with survival (P=0.001, P<0.001 and P<0.001, respectively). The final result of the 3-step multivariate analysis demonstrated that LODDS was superior to the other two N categories. Patients in the same pN or LNR classifications may be classified into different LODDS stages with different prognoses. Thus, LODDS may be a meaningful prognostic indicator and superior to the pN and LNR classifications in CRC patients who undergo curative (R0) resection.

Marriage is a dependent risk factor for mortality of colon adenocarcinoma without a time-varying effect

BACKGROUND

It has been well recognized that the effects of many prognostic factors could change during long-term follow-up. Although marriage has been proven to be a significant prognostic factor for the survival of colon cancer, whether the effect of marriage is constant with time remain unknown. This study analyzed the impact of marital status on the mortality of colon cancer patients with an extended Cox model that allowed for time-varying effects.

METHODS

We identified 71,955 patients who underwent colectomy between 2004 and 2009 to treat colon adenocarcinoma from the Surveilance, Epidemiology and End Results Database. The multivariate extended Cox model was used to evaluate the effect of marital status on all-cause mortality, while the Fine-Gray competing risks model was used for colon cancer-specific mortality, with death from other causes as the competing risk.

RESULTS

The unmarried patients carried a 1.37-fold increased risk of all-cause mortality compared with the married patients (95%CI: 1.33-1.40; p<0.001), and the hazard ratio remained constant over time. Being unmarried was at a higher risk of death from colon adenocarcinoma as well as death from other causes. Four variables including tumor site, tumor grade, sex and TNM stage were proved to have time-varying effects on survival.

CONCLUSIONS

Marriage is a dependent prognosis factor for survival of surgically treated colon adenocarcinoma patients. Psychological interventions are suggested to improve receipt of treatment among unmarried patients, as their poor survival may be due to the inefficient treatment.