Impact of lymph node retrieval on surgical outcomes in colorectal cancers

The oncologic safety of left colectomy with modified complete mesocolic excision for distal transverse colon cancer: Comparison with descending colon cancer

BACKGROUND

The optimal surgical approach for distal transverse colon cancer has not been well established. This study aimed to evaluate the oncologic safety of left colectomy with a modified complete mesocolic excision for distal transverse colon cancer as compared with descending colon cancer.

MATERIAL AND METHODS

This study involved 383 patients who underwent left colectomy with modified complete mesocolic excision for non-metastatic distal transverse and splenic flexure colon (transverse group, N = 110) and descending colon cancer (descending group, N = 237) from 3 institutions. Recurrence-free survival (RFS) and overall survival (OS) were compared between the two groups.

RESULTS

Baseline characteristics between the two groups were similar except for the length of the distal margin (transverse group = 11.0 cm vs descending group = 9.0 cm, p = 0.004). During a median follow-up of 47.0 months, RFS and OS were not different between the transverse and descending groups (5-year RFS: 82% vs 71%, p = 0.139; 5-year OS: 83% vs 79%, p = 0.416, respectively). In multivariable analysis, RFS and OS were not different between the two groups (transverse group vs. descending group: adjusted hazard ratio [aHR] = 1.557, 95% CI = 0.786-3.084, p = 0.204; aHR = 1.251, 95% CI = 0.530-2.952, p = 0.609).

CONCLUSION

The oncologic outcomes of left colectomy with a modified complete mesocolic excision of distal transverse colon cancer were comparable to those of descending colon cancer. Left colectomy with a modified complete mesocolic excision can be an acceptable surgical treatment for distal transverse colon cancer.

Prognostic nomogram based on log odds of positive lymph nodes for gastric carcinoma patients after surgical resection

Aim: To build a prognostic nomogram based on log odds of positive lymph nodes for patients with gastric carcinoma (GC) after resection, and to compare the predictive performance with the American Joint Committee on Cancer (AJCC) staging system and lymph node ratio (LNR). Methods: Multivariate analyses were performed to identify the independent variables for cancer-specific survival (CSS). A nomogram was constructed based on independent clinicopathological factors. Results: The C-indices for predicting CSS were 0.674 in development cohort and 0.647 in validation cohort, which were higher than that of the AJCC staging system and LNR. Conclusion: The nomogram was more accurate than the AJCC staging system and LNR for predicting CSS in patients undergoing resection for GC.

Expression of 15-lipoxygenase-1 in Merkel cell carcinoma is linked to advanced disease

BACKGROUND

The purpose of this study was to determine whether the expression of 15-lipoxygenase-1 (ALOX15) in primary tumour specimens predicts lymph node metastasis and subsequently clinical outcome in Merkel cell carcinoma (MCC) patients.

METHODS

A retrospective medical chart review of 33 patients was performed between 1994 and 2014. Eleven out of 33 (33%) Patients with primary MCC stages I and II were categorised as group I. Twenty two out of 33 (67%) Patients with regional lymph node metastases and/or distant metastases were defined as group II. All available tumour samples were immunostained for ALOX15, Podoplanin and MCPyV large T-protein antibody.

RESULTS

ALOX15 expression was observed in 19/23 (83%) primary tumour samples and in all lymph node metastasis. Primary tumours in patients with stage III and IV disease showed a higher expression rate of ALOX15 compared to patients with early stage disease (11/12 (92%) and 8/11 (73%), respectively). In group I, five patients (45%) were MCPyV positive, whereas in group II, 15 patients (68%) were MCPyV positive. The median lymphatic vessel density in ALOX15 negative group I primary tumour samples was lower compared to the median lymphatic vessel density in ALOX15 positive group I primary tumour probes (2.7 range, 1-4.3 vs 4.7 range, 4.0-7.3). Furthermore, all 17 samples of MCC metastases showed ALOX15 expression with a median lymphatic vessel density (not lymph node metastases) of 5.3 (range 2.0-7.3).

CONCLUSION

In the current study, we were able to show ALOX15 expression in the primary MCC sample and the metastasis sample. Based on the findings of the current study, expression rate of ALOX15 in primary MCC and metastases is possibly linked to an increased lymphatic vessel density.

Prognostic role of the lymph node ratio in node positive colorectal cancer: a meta-analysis

The lymph node ratio (LNR) (i.e. the number of metastatic lymph nodes divided by the number of totally resected lymph nodes) has recently emerged as an important prognostic factor in colorectal cancer (CRC). However, the tumor node metastasis (TNM) staging system for colorectal cancer does not consider it as a prognostic parameter. Therefore, we conducted a meta-analysis to evaluate the prognostic role of the LNR in node positive CRC. A systematic search was performed in PubMed, Embase and the Cochrane Library for relevant studies up to November 2015. As a result, a total of 75,838 node positive patients in 33 studies were included in this meta-analysis. Higher LNR was significantly associated with shorter overall survival (OS) (HR = 1.91; 95% CI 1.71–2.14; P = 0.0000) and disease free survival (DFS) (HR = 2.75; 95% CI: 2.14–3.53; P = 0.0000). Subgroup analysis showed similar results. Based on these results, LNR was an independent predictor of survival in colorectal cancer patients and should be considered as a parameter in future oncologic staging systems.

MicroRNAs and their role for T stage determination and lymph node metastasis in early colon carcinoma

Worldwide, colon cancer is among the most common cancer entities. Understanding the molecular background is the key to enable accurate stage determination, which is crucial to assess optimal therapy options. The search for preoperative biomarkers is ongoing. In recent years, several studies have proposed a diagnostic and prognostic role for miRNAs in cancer. Aim of this study was to evaluate miRNA expression patterns correlating with tumor stage, especially lymph node metastasis, in primary colon carcinoma tissue. Screening was accomplished using GeneChip^® miRNA v3.0 arrays (Thermo Fisher Scientific, Waltham, MA, USA) and validated via TaqMan^® qPCR assays (Thermo Fisher Scientific, Waltham, MA, USA) to investigate miRNA expressions in 168 FFPE and 83 fresh frozen colon carcinoma samples. Regarding lymph node status, analyses displayed no significantly differential miRNA expression. Interestingly, divergent expression of miR-18a-5p, miR-20a-5p, miR-21-5p, miR-152-3p and miR-1973 was detected in stage pT1. Although miRNAs might not represent reliable biomarkers regarding lymph node metastasis status, they could support risk assessment in stage T1 tumors.

The prognostic value of lymph node yield in the earliest stage of colorectal cancer: a multicenter cohort study

BACKGROUND

In patients with stage II colorectal cancer (CRC) the number of surgically retrieved lymph nodes (LNs) is associated with prognosis, resulting in a minimum of 10-12 retrieved LNs being recommended for this stage. Current guidelines do not provide a recommendation regarding LN yield in T1 CRC. Studies evaluating LN yield in T1 CRC suggest that such high LN yields are not feasible in this early stage, and a lower LN yield might be appropriate. We aimed to validate the cut-off of 10 retrieved LNs on risk for recurrent cancer and detection of LN metastasis (LNM) in T1 CRC, and explored whether this number is feasible in clinical practice.

METHODS

Patients diagnosed with T1 CRC and treated with surgical resection between 2000 and 2014 in thirteen participating hospitals were selected from the Netherlands Cancer Registry. Medical records were reviewed to collect additional information. The association between LN yield and recurrence and LNM respectively were analyzed using 10 LNs as cut-off. Propensity score analysis using inverse probability weighting (IPW) was performed to adjust for clinical and histological confounding factors (i.e., age, sex, tumor location, size and morphology, presence of LNM, lymphovascular invasion, depth of submucosal invasion, and grade of differentiation).

RESULTS

In total, 1017 patients with a median follow-up time of 49.0 months (IQR 19.6-81.5) were included. Four-hundred five patients (39.8%) had a LN yield ≥ 10. Forty-one patients (4.0%) developed recurrence. LN yield ≥ 10 was independently associated with a decreased risk for recurrence (IPW-adjusted HR 0.20; 95% CI 0.06-0.67; P = 0.009). LNM were detected in 84 patients (8.3%). LN yield ≥ 10 was independently associated with increased detection of LNM (IPW-adjusted OR 2.27; 95% CI 1.39-3.69; P = 0.001).

CONCLUSIONS

In this retrospective observational study, retrieving < 10 LNs was associated with an increased risk of CRC recurrence, advocating the importance to perform an appropriate oncologic resection of the draining LNs and diligent LN search when patients with T1 CRC at high-risk for LNM are referred for surgical resection. Given that both gastroenterologists, surgeons and pathologists will encounter T1 CRCs with increasing frequency due to the introduction of national screening programs, awareness on the consequences of an inadequate LN retrieval is of utmost importance.

Alteration of Leptin and Adiponectin in Multistep Colorectal Tumorigenesis

BACKGROUND

There is an established link between obesity related metabolic derangement and colorectal cancer development. Recently, we developed a metabolic-colorectal cancer risk score. In this follow-up study, we studied its association with colorectal neoplasm by measuring two major metabolic syndrome biomarkers, leptin and adiponectin.

OBJECTIVES

To evaluate the serum levels of leptin and adiponectin in patients with colorectal polyps and colorectal cancer and to determine any correlation with metabolic risk score.

RESULTS

In total, 130 individuals were studied: 30 controls without colonic pathology, 18 with colonic adenoma (CAP), and 82 with colorectal adenocarcinoma (CRC, 17 cases of T1-2 and 65 cases of T3-4). The metabolic risk scores in CAP and T1-2 CRC were higher than those in the controls and T3-4 CRC cases. There were no statistically significant differences in leptin levels among CAPs, CRCs, and controls. Both leptin and adiponectin levels reflected differences in body mass index and metabolic risk scores. Cases in the CAP group and early T-stage CRC groups had lower adiponectin levels (14.03 and 13.01 mg/ml, respectively) than the no polyps group (19.5mg/ml, p = 0.03). The average serum adiponectin level in the invasive cancer group (18.5 ng/ml) was comparable with that of the control group.

CONCLUSIONS

The level of serum adiponectin was positively correlated with the metabolic risk score. Decreased serum adiponectin was significantly associated with the development of colorectal adenoma and early stage colorectal carcinoma.

Lymph node retrieval in colorectal cancer: determining factors and prognostic significance

PURPOSE

The study aimed to analyze clinicopathological factors that determine the extent of lymph node retrieval and to evaluate its prognostic impact in patients with colorectal cancer (CRC).

METHODS

The number of retrieved lymph nodes was analyzed in 381 CRC specimens. Lymph node count was related to different clinicopathological variables by binary logistic regression. Progression-free survival (PFS) and cancer-specific survival (CSS) were determined using the Kaplan-Meier method and Cox regression models.

RESULTS

The median number of retrieved lymph nodes was 20 (mean 21 ± 10, range 1-65) in right-sided, 13 (16 ± 10, 1-66) in left-sided, and 15 (18 ± 11, 3-64) in rectal tumors. The number of retrieved lymph nodes was independently associated with T-classification (p < 0.001), N-classification (p = 0.014), and tumor size (p = 0.005) as well as right-sided tumor location (p = 0.012). There was no association with age, sex, tumor grade, mismatch-repair status, and lymph or blood vessel invasion. The longer the surgical specimen, the higher were the numbers of retrieved and positive lymph nodes (p < 0.001, respectively). In patients with locally advanced (T3/T4) tumors (n = 283), analysis of more than 12 lymph nodes was independently associated with PFS (HR = 0.63, p = 0.025) and CSS (HR = 0.54, p = 0.004). In the subset of T3/T4 N0 patients (n = 130), analysis of more than 12 lymph nodes similarly proved to be an independent predictor of outcome (PFS, HR = 0.48, p = 0.046; OS, HR = 0.41, p = 0.026).

CONCLUSION

The number of retrieved lymph nodes is associated with higher tumor stage, tumor size, and right-sided location. Low lymph node count indicates adverse outcome in patients with locally advanced (T3/T4) disease.

Surgical quality in colorectal cancer

Objective

To determine the quality of surgical management offered to patients with colorectal cancer (CRC) as measured by adequacy of nodal resections and compare variations across the major hospitals in Jamaica.

Method

Data was obtained from the CRC Registry of patients diagnosed and treated surgically for CRC during the 3-year period commencing January 1, 2011. Variables analyzed included tumor site, stage and number of lymph nodes resected across hospitals.

Results

During the period under review 60% (349) of 586 patients had resections and formed the basis of this study. Of these 49% were treated at the UHWI, 27% from the KPH and STH, 15% from CRH and MRH and 8% from a private laboratory (DPS). Patient distribution was similar at UHWI compared to the others with mean age (61 vs 62) and with slightly more women having surgery (53% Vs 54%) (UHWI vs Others). For tumor grade, margin status, lymphovascular and depth of invasion (majority T3) there was no difference between UHWI and the other sites, although a smaller percentage of tumors treated at UHWI had Crohn's like reaction (p = 0.01). There was a larger proportion of sigmoid cancer at UHWI while the reverse trend was seen in cancers of the rectum (p = 0.027). The tumors treated at UHWI have a larger median number of regional nodes when compared to the other facilities (14 vs 10; p < 0.001) and also more likely to have positive nodes, as were women and younger patients. Comparison across facilities revealed that the proportion of tumors classed as well differentiated, circumferential margin involvement, and having lymphovascular invasion were higher for specimens processed at the private facility (p = 0.021, 0.035, 0.01 respectively). Histopathology reports of tumors treated at UHWI and DPS had median 14 and 18 nodes respectively while at NPH laboratory and CRH they were 9 and 10 respectively (p < 0.001), whilst those of the ascending, descending, sigmoid colon and rectum had median 15, 11, 13, 11 nodes respectively (p < 0.001).

Conclusions

This review demonstrates measurable differences in the surgery and histopathological reports for CRC patients treated across the island. Given adjuvant treatment and prognostic implications there is room for improvement.

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This manuscript documents lymph node resection for colorectal cancer between hospitals in Jamaica.

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Left hemicolectomies and proctectomy specimens were not meeting acceptable standards.

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This has important treatment and prognostic implications.

Stage migration vs immunology: The lymph node count story in colon cancer

Lymph node staging is of crucial importance for the therapy stratification and prognosis estimation in colon cancer. Beside the detection of metastases, the number of harvested lymph nodes itself has prognostic relevance in stage II/III cancers. A stage migration effect caused by missed lymph node metastases has been postulated as most likely explanation for that. In order to avoid false negative node staging reporting of at least 12 lymph nodes is recommended. However, this threshold is met only in a minority of cases in daily practice. Due to quality initiatives the situation has improved in the past. This, however, had no influence on staging in several studies. While the numbers of evaluated lymph nodes increased continuously during the last decades the rate of node positive cases remained relatively constant. This fact together with other indications raised doubts that understaging is indeed the correct explanation for the prognostic impact of lymph node harvest. Several authors assume that immune response could play a major role in this context influencing both the lymph node detectability and the tumor’s behavior. Further studies addressing this issue are need. Based on the findings the recommendations concerning minimal lymph node numbers and adjuvant chemotherapy should be reconsidered.

Association of Wilms' tumor 1 gene single-nucleotide polymorphism rs16754 with colorectal cancer

Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality worldwide. Our recent study demonstrated that the expression of Wilms' tumor 1 gene (WT1) is associated with surgical outcome in CRC patients. The present study aimed to investigate the genetic association of the single-nucleotide polymorphism rs16754 in the WT1 gene with the occurrence of CRC, using an age-matched case-control study design. In addition, the correlation between genotype and WT1 expression was investigated. Genomic DNA samples from 104 CRC cases, aged 15-65 years, and 208 healthy controls, were genotyped for rs16754 using the TaqMan genotyping method. The genotype distribution conformed to the Hardy-Weinberg equilibrium (P=0.80). The overall minor allele frequency (MAF) of rs16754 (allele A) was 0.33. The MAF among CRC cases was significantly higher compared with that in controls (0.39 vs. 0.31, respectively; P=0.03). The AA genotype was significantly associated with the disease (odds ratio = 2.51, 95% confidence interval: 1.24-5.07, P=0.01). Cases with the AA genotype exhibited a significantly poorer 3-year overall survival (60%), compared with those with the GG or GA genotypes (80%) (log-rank test, P<0.01). Reverse transcription quantitative polymerase chain reaction analysis demonstrated that the expression of WT1 in tumor tissues was higher compared with that in normal tissue; however, there were no significant differences in its expression among different genotypes. Therefore, rs16754 was found to be associated with the occurrence and prognosis of CRC in our subjects.

Lymph Node Yield in Colon Cancer: Individuals Can Make the Difference

AIM

To investigate the influence of individual surgeons and pathologists on examining an adequate (i.e. ≥10) number of lymph nodes in colon cancer resection specimens.

PATIENTS AND METHODS

The number of lymph nodes was evaluated in surgically treated patients for colon cancer at our hospital from 2008 through 2010, excluding patients who had received neo-adjuvant treatment. The patient group consisted of 156 patients with a median age of 73 (interquartile range (IQR) 63-82 years) and a median of 12 lymph nodes per patient (IQR 8-15). In 106 patients (67.9%), 10 or more nodes were histopathologically examined.

RESULTS

At univariate analysis, the examination of ≥10 nodes was influenced by tumour size (p = 0.05), tumour location (p = 0.015), type of resection (p = 0.034), individual surgeon (p = 0.023), and pathologist (p = 0.005). Neither individual surgeons nor pathologists did statistically and significantly influence the chance of finding an N+ status. Age (p = 0.044), type of resection (p = 0.007), individual surgeon (p = 0.012) and pathologist (p = 0.004) were independent prognostic factors in a multivariate model for finding ≥10 nodes.

CONCLUSION

Though cancer staging was not affected in this study, individual efforts by surgeons and pathologists play a critical role in achieving optimal lymph node yield through conventional methods.

The prognostic value of the number of lymph nodes removed in patients with node-negative colorectal cancer

BACKGROUND

To investigate the prognostic significance of the number of lymph nodes removed in colorectal cancer (CRC) patients with no metastatic lymph node.

PATIENTS AND METHODS

The clinicopathological data of 461 CRC patients was analyzed. In order to compare the survival of patients who had fewer lymph nodes removed versus the survival of patients who had 1-3 metastatic lymph node(s), a separate group of 74 N1 disease patients were also included in the study. All patient data were collected prospectively. Kaplan-Meier method was used for calculation and plotting of the survival curves of the patient groups, and log-rank test was used for the comparison of the survival curves.

RESULTS

Cancer-specific survival (CSS) rates of patients who had 1-7 lymph node(s) and 8-11 lymph nodes removed were significantly worse than those who had 12 or more lymph nodes removed (p = 0.006 and p = 0.037, respectively), while CSS was not significantly different between those who had 1-7 versus 8-11 lymph node(s) removed (p = 0.647); this grouping had independent prognostic significance in Cox analysis (p = 0.006). CSS of patients with N1 disease was not significantly different from those who had 1-7 and 8-11 lymph node(s) removed (p = 0.312 and p = 0.165, respectively), while it was significantly worse than CSS of patients who had 12 or more lymph nodes removed (p = 0.001).

CONCLUSION

In colorectal cancer patients whose removed lymph nodes are non-metastatic, removal of at least 12 lymph nodes will determine the lymph node status reliably.

Lymph node ratio improves TNM and Astler-Coller's assessment of colorectal cancer prognosis: an analysis of 761 node positive cases

BACKGROUND

Prognosis assessment of node-positive colorectal cancer patients by Astler-Coller (AC) and TNM classifications is suboptimal. Recently, several versions of lymph node ratio (LNR; ratio metastatic/examined nodes) have been proposed but are still mostly unused.

METHODS

The prognostic value of several criteria, including LNR (two classes-LNR1 and LNR2-identified by a 15% cut-off) was studied in 761 consecutive patients, from 2000 through 2010. The relationships between total examined nodes, N, T and LNR were also analysed. LNR1 and LNR2 patients' survival was analysed within AC and TNM subgroups, and then coupled with them.

RESULTS

Age, tumour location and LNR are independent factors predicting survival. The relationships between LNR, N stage and T stage with examined nodes suggest confusing factors. LNR allows for identification of subgroups with different survival within AC and TNM classifications (p < 0.0001). Patients with LNR class discordant from AC stage (LNR1-C2 and LNR2-C1) have a similar 5-year survival (54 and 57%, respectively). LNR2 and TNM stage IIIC define a poor 5-year prognosis (33%).

CONCLUSIONS

LNR is a powerful prognosis predictor, easily integrated with TNM and AC classifications to improve prognosis assessment and facilitate clinical use. Possible confusing factors should be considered in future studies.

Endoscopic obstruction is associated with higher risk of acute events requiring emergency operation in colorectal cancer patients

INTRODUCTION

Unplanned emergency operations in colorectal cancers (CRC) are generally associated with increased risk of operative complications. This study aimed to examine the association, if any, between an endoscopic finding of obstructing tumor and the subsequent need for an emergency operation, with the aim of determining if this finding could be useful in identifying CRC cases who are more likely to require an emergency operation.

METHODS

The records of CRC cases operated on in our institute during the years 2002-2011 were retrospectively reviewed regarding an endoscopic obstruction (eOB), defined as a luminal obstruction of the colon or rectum severe enough to prevent the colonoscope from passing beyond the tumor. The eOBs were analyzed against outcomes in terms of need for emergency operation, surgical complications and overall survival (OS).

RESULTS

A total of 329 CRCs which had been operated on during the study period had complete colonoscopic data. eOB was diagnosed in 209 cases (64%). Occurrence of eOB was not correlated with clinical symptoms. Colon cancer had a higher incidence of eOB (70%) than rectal cases (50%) (p-value < 0.01). eOB was significantly associated with higher tumor size and more advanced T-stage (p < 0.01). Twenty-two cases (7%) had required an emergency operation before their scheduled elective surgery. The cases with eOB had a significantly higher risk of requiring an emergency operation while waiting for their scheduled procedure (p-value < 0.01), and these emergency surgeries had more post-operative complications (36%) than elective procedures (13%) (p-value 0.01) and poorer OS (p-value < 0.01).

CONCLUSION

Regardless of the presenting symptom, luminal obstruction severe enough to prevent further passage of a colonoscope should prompt the physician to consider an urgent surgery.