Prognostic impact of the metastatic lymph node ratio on survival in rectal cancer

The Role of Nonmetastatic Lymph Nodes in the Survival of Colorectal Cancer: A Systematic Review

Objective

In this review, we aim to provide an overview of literature on lymph node (LN) histomorphological features and their relationship with the prognosis in colorectal cancer (CRC).

Background

Lymph nodes play a crucial role in the treatment and prognosis of CRC. The presence of LN metastases considerably worsens the prognosis in CRC patients. Literature has shown that the total number of LNs and the number negative LNs (LNnegs) has prognostic value in CRC patients. In esophageal carcinoma, LN size seems to be surrogate of the host antitumor response and a potentially clinically useful new prognostic biomarker for (y)pN0 esophageal carcinoma.

Methods

A comprehensive search was performed in Pubmed, Embase, Medline, CINAHL, and the Cochrane library in March 2021. The PRISMA guidelines were followed. Only studies focusing on histomorphological features and LN size and their relation to overall survival were selected.

Results

A total of 9 unique articles met all inclusion criteria and were therefore included in this systematic review. Six of these studies investigated HMF (eg, paracortical hyperplasia, germinal center predominance, and sinus histiocytosis) and 4 studies LNneg size and their relationship with overall survival. The presence of paracortical hyperplasia and an increased number of large LNnegs is related to a more favorable prognosis in CRC.

Conclusion

The results of this systematic review seem to support the hypothesis that there is a relationship between the host antitumor response reflected in different histomorphological reaction patterns visible in LNnegs and LNneg size related to survival in CRC patients.

Progress in the diagnosis of lymph node metastasis in rectal cancer: a review

Historically, the chief focus of lymph node metastasis research has been molecular and clinical studies of a few essential pathways and genes. Recent years have seen a rapid accumulation of massive omics and imaging data catalyzed by the rapid development of advanced technologies. This rapid increase in data has driven improvements in the accuracy of diagnosis of lymph node metastasis, and its analysis further demands new methods and the opportunity to provide novel insights for basic research. In fact, the combination of omics data, imaging data, clinical medicine, and diagnostic methods has led to notable advances in our basic understanding and transformation of lymph node metastases in rectal cancer. Higher levels of integration will require a concerted effort among data scientists and clinicians. Herein, we review the current state and future challenges to advance the diagnosis of lymph node metastases in rectal cancer.

Prognostic Factors of Recurrence and Survival in Operated Patients with Colorectal Cancer

BACKGROUND: The recurrence of colorectal cancers is considered to be one of the greatest post-surgical complications that is affected by various factors. This study was designed to investigate the prognostic factors that affect the recurrence and survival of patients with colon and rectal cancers. METHODS: A retrospective study was performed on 380 patients with colorectal cancers who underwent surgery were enrolled in the study (152 patients with colon cancer and 228 patients with rectal cancer). Preoperative serum albumin level, type of surgery, tumor size, differentiation grade, proximal, distal and radial, and marginal involvement, the total number of excised lymph nodes, the number of involved lymph nodes, and tumor stage were recorded. Also, the incidences of recurrence and metastasis were recorded during the study. RESULTS: 380 patients with a mean age of 57.11 years were enrolled in the study. 152 patients with an average age of 57.57 years were diagnosed as having colon cancer. Recurrence and metastasis occurred in two patients (1.3%) and five patients (3.3%), respectively. 18 patients (11.8%) died because of colon cancer. 228 patients with a mean age of 56.81 had rectal cancer. Recurrence was seen in 19 patients (8.3%) and metastasis in 33 patients (14.5%). 38 patients (16.7%) died because of rectal cancer. Tumor size and involved lymph nodes were independent prognostic factors for the recurrence and metastases of colon cancer. Only involved lymph nodes were associated with death due to colon cancer. Independent prognostic factors for rectal cancer metastasis include serum albumin level and age. The total number of excised lymph nodes was the only predictor of tumor recurrence and death in rectal cancer. The median survival times of colon and rectal cancers were 90 and 110 months, respectively. CONCLUSION: The size of the tumor and the number of involved lymph nodes were independent prognostic factors for recurrence and metastasis of colon cancer. Also, the number of involved lymph nodes was associated with colon cancer-related deaths. In the case of rectal cancer, serum albumin levels and age predicted metastases. Only the total number of excised lymph nodes had a reverse relationship with recurrence and rectal cancer-related death.

Radiomics Based on T2-Weighted Imaging and Apparent Diffusion Coefficient Images for Preoperative Evaluation of Lymph Node Metastasis in Rectal Cancer Patients

Purpose

To develop and validate a radiomics nomogram based on T2-weighted imaging (T2WI) and apparent diffusion coefficient (ADC) features for the preoperative prediction of lymph node (LN) metastasis in rectal cancer patients.

Materials and Methods

One hundred and sixty-two patients with rectal cancer confirmed by pathology were retrospectively analyzed, who underwent T2WI and DWI sequences. The data sets were divided into training (n = 97) and validation (n = 65) cohorts. For each case, a total of 2,752 radiomic features were extracted from T2WI, and ADC images derived from diffusion-weighted imaging. A two-sample t-test was used for prefiltering. The least absolute shrinkage selection operator method was used for feature selection. Three radiomics scores (rad-scores) (rad-score 1 for T2WI, rad-score 2 for ADC, and rad-score 3 for the combination of both) were calculated using the support vector machine classifier. Multivariable logistic regression analysis was then used to construct a radiomics nomogram combining rad-score 3 and independent risk factors. The performances of three rad-scores and the nomogram were evaluated using the area under the receiver operating characteristic curve (AUC). Decision curve analysis (DCA) was used to assess the clinical usefulness of the radiomics nomogram.

Results

The AUCs of the rad-score 1 and rad-score 2 were 0.805, 0.749 and 0.828, 0.770 in the training and validation cohorts, respectively. The rad-score 3 achieved an AUC of 0.879 in the training cohort and an AUC of 0.822 in the validation cohort. The radiomics nomogram, incorporating the rad-score 3, age, and LN size, showed good discrimination with the AUC of 0.937 for the training cohort and 0.884 for the validation cohort. DCA confirmed that the radiomics nomogram had clinical utility.

Conclusions

The radiomics nomogram, incorporating rad-score based on features from the T2WI and ADC images, and clinical factors, has favorable predictive performance for preoperative prediction of LN metastasis in patients with rectal cancer.

Immunohistochemical-based molecular subtyping of colorectal carcinoma using maspin and markers of epithelial-mesenchymal transition

The aim of the present study was to classify colorectal carcinoma (CRC) into molecular subtypes, based on immunohistochemical (IHC) assessments. A total of 112 CRC samples were molecularly classified based on the expression levels of epithelial-mesenchymal transition (EMT)-associated IHC markers. A total of three molecular subtypes were defined: Epithelial, membrane positivity for E-cadherin and β-catenin, negative for vimentin; mesenchymal, E-cadherin-negative, nuclear β-catenin- and vimentin-positive; and hybrid cases, epithelial tumor core and mesenchymal tumor buds. Most of the cases were diagnosed as moderately differentiated adenocarcinoma (n=89; 79.46%). The majority of cases (n=100; 89.28%) exhibited a mismatch repair proficient status (microsatellite stable CRCs). A predominance of epithelial-type (n=51; 45.54%) and hybrid CRCs (n=47; 41.96%) was observed, whereas a few cases (n=14; 12.50%) were classified as mesenchymal-type CRCs. This molecular classification was associated with pathological stage (P<0.01), pT stage (P=0.04), pN stage (P<0.01), the grade of tumor budding (P=0.04), and maspin expression in both the tumor core (P=0.04) and the invasion front (P<0.01). The mesenchymal-type cases predominantly exhibited lymph node metastases, high-grade budding and a tendency towards maspin nuclear predominance. All epithelial-type cases with maspin-only expression (n=18) were non-metastatic. Patients with CRC of the epithelial subtype and those with a lymph node ratio (LNR) ≤0.15 presented the best overall survival, followed by those with hybrid and mesenchymal subtypes. Nuclear maspin positivity was more frequent in cases with a high-budding degree compared with those with a low-budding degree (P=0.03). The EMT-associated molecular classification of CRCs may be used to identify the most aggressive CRCs, which show a mesenchymal phenotype, high-budding degree, maspin nuclear positivity and lymph node metastases. The pN stage, LNR and budding degree of patients, which can be evaluated with maspin expression, remain the most important prognostic factors.

Clinical Implications of Lymph Node Metastasis in Colorectal Cancer: Current Status and Future Perspectives

Lymph node metastasis is regarded as an indubitable prognostic factor for predicting disease recurrence and survival in patients with colorectal cancer. Lymph node status based on examination of a resected specimen is a key element of the current staging system and is also a crucial factor to determine use of adjuvant chemotherapy after surgical resection. However, the current tumor-node-metastasis (TNM) staging system only incorporates the number of metastatic lymph nodes in the N category. Numerous attempts have been made to supplement this simplified N staging including lymph node ratio, distribution of metastatic lymph nodes, tumor deposits, or extracapsular invasion. In addition, several attempts have been made to identify more specific prognostic factors in resected colorectal specimens than lymph node status. In this review, we will discuss controversies in lymph node staging and factors that may influence survival beyond lymph node status.

Oncologic Outcomes of Postoperative Chemoradiotherapy Versus Chemotherapy Alone in Stage II and III Upper Rectal Cancer

PURPOSE

The aim of this study was to assess oncological outcomes of postoperative radiotherapy plus chemotherapy (CRT) versus chemotherapy alone (CTx) in stage II or III upper rectal cancer patients who underwent curative surgery.

METHODS

We retrospectively reviewed 263 consecutive patients with pathologic stage II or III upper rectal cancer who underwent primary curative resection with postoperative CRT or CTx from January 2008 to December 2014 at Chonnam National University Hwasun Hospital. Multivariate and propensity score matching analyses were used to reduce selection bias.

RESULTS

Median follow-up was 48.1 months for the entire cohort and 53.5 months for the matched cohort. In subgroup analysis of the propensity score matched cohort, the 3-year local recurrence-free survival was 94.1% (95% confidence interval [CI], 87.8%-100%) in the CRT group and 90.1% (95% CI, 82.8%-97.9%) in the CTx group (P = 0.370). No significant difference in disease-free survival was observed according to treatment type. On multivariate analysis, circumferential resection margin involvement (hazard ratio [HR], 2.386; 95% CI, 1.190-7.599; P = 0.032), N stage (HR, 6.262; 95% CI, 1.843-21.278, P = 0.003), and T stage (HR, 5.896, 95% CI, 1.298-6.780, P = 0.021) were identified as independent risk factors for local recurrence of tumors of the upper rectum.

CONCLUSION

Omission of radiotherapy in an adjuvant treatment setting may not jeopardize oncologic outcomes in stages II and III upper rectal cancer.

Proposal of a modified American Joint Committee on Cancer staging scheme for resectable pancreatic ductal adenocarcinoma with a lymph node ratio-based N classification: A retrospective cohort study

The recently launched 8th edition of the American Joint Committee on Cancer (AJCC) staging scheme for pancreatic ductal adenocarcinoma (PDAC) did not account for the impact of the total examined lymph node count on prognostic accuracy. In this population-based cohort study, we proposed a modified AJCC staging scheme by incorporating a lymph node ratio (LNR)-based N classification for patients with resectable PDAC.We analyzed 8615 patients with resectable PDAC from the Surveillance, Epidemiology, and End Results database between 2004 and 2013. The optimal cut-off points for LNR were identified by recursive partitioning, and an LNR-based N classification was designed accordingly.The LNR-based N classification could further stratify patients with the 8th AJCC N1 and N2 disease into subgroups with significantly different overall survival (P < .001 for both). By replacing the 8th AJCC N classification with the corresponding LNR-based N classification, we further proposed a modified AJCC staging scheme. The modified AJCC staging outperformed the 8th AJCC staging in terms of the discriminatory capacity measured by the concordance index and Akaike information criterion, and the prognostic homogeneity assessed by using the likelihood ratio chi-squared test and stratified survival analysis.Replacing the 8th AJCC N classification with the LNR-based N classification can improve the prognostic performance of the 8th AJCC staging scheme for PDAC.

A systematic review of the prognostic value of lymph node ratio, number of positive nodes and total nodes examined in pancreatic ductal adenocarcinoma

BACKGROUND Pancreatic ductal adenocarcinoma is the most common pancreatic cancer. Five-year overall survival is currently 3.3-6.0%. The aim of this review was to evaluate the prognostic value of lymph node ratio, number of positive nodes and total nodes examined on overall survival rate following pancreatic resection. MATERIALS AND METHODS A literature search was conducted of MEDLINE, EMBASE, the Cochrane Library and Central Register of Controlled Trials and the Cochrane Database of Systematic Review databases, from January 1996 to January 2016. RESULTS Overall, 19 studies including 4,883 patients examined the relationship between lymph node ratio and overall survival. A high lymph node ratio was associated with decreased overall survival in 17 studies. A total of 12 studies examined the relationship between the number of positive nodes and overall survival, and 11 studies revealed that an increase in the number of positive nodes was associated with decreased overall survival. In 15 studies examining the relationship between the total nodes examined and overall survival, there was no association with overall survival in 12 studies. CONCLUSIONS Lymph node ratio and number of positive nodes are factors associated with overall survival in pancreatic ductal adenocarcinoma, but not total nodes examined.

Preoperative SCC Antigen, CRP Serum Levels, and Lymph Node Density in Oral Squamous Cell Carcinoma

The prognostic significance of squamous cell carcinoma antigen (SCC-Ag) and C-reactive protein (CRP) levels and lymph node density (LND) has been individually recognized in oral squamous cell carcinoma (OSCC). We investigated the relationship between preoperative serum markers (SCC-Ag and CRP) and postoperative prognostic marker (LND) in this study. We retrospectively analyzed 277 OSCC patients who underwent primary curative resection and neck dissection with/or without adjuvant therapy between March 2008 and November 2013. Serum SCC-Ag and CRP levels were measured preoperatively. Distant metastasis, overall survival (OS), and disease-free survival (DFS) were used to evaluate the prognostic significance of preoperative SCC-Ag and CRP levels in relation to LND. LND (cutoff point ≥0.06) correlated with the pathologic tumor status, pathologic nodal metastasis, degree of differentiation, tumor stage, tumor depth (≥10 mm vs <10 mm), and perineural invasion (all P values were <0.001). LND was significantly associated with development of distant metastasis, DFS, and OS (all P values were <0.001). Preoperative elevated CRP and SCC-Ag levels were significantly associated with LND (P = 0.006), DFS (P < 0.001), and OS (P < 0.001). LND patients were further stratified into prognostic groups according to their SCC-Ag and CRP levels (DFS: P = 0.010; OS: P = 0.003). LND correlated with the incidence of DM, DFS, and OS in patients with OSCC. Concurrent elevated preoperative SCC-Ag and CRP levels are predictors for LND. In addition, SCC-Ag and CRP are markers for classifying high-risk LND patients with OSCC into subgroups.

Prognostic Impact of the Metastatic Lymph Node Ratio on Survival in Gastric Cancer

Research on the prognostic value of lymph node ratio (LNR) in gastric cancer (GC) remains limited and controversial results were obtained. In this study, we aimed to evaluate whether LNR was an independent prognostic factor for gastric carcinoma. A retrospective review of a database of gastric cancer patients was performed to determine the effect of the LNR on the overall survival (OS) and the disease-free survival (DFS). Of the total 135 patients with gastric cancer who underwent resection between March 2012 and December 2013, 44 patients with non metastatic gastric cancer were eligible for analysis. Survival curves were estimated using the Kaplan-Meier method. Cox regression analyses, after adjustments for potential confounders, were used to evaluate the relationship between the LNR and survival. According to the cutoff point 0.37 (37 %), the one-year OS rate for LNR ≤ 37 % was significantly better than that for LNR > 37 % (91.3 % and 61.9 %, respectively, P = 0.02). The one-year DFS for LNR ≤ 37 % was significantly better than that for LNR > 37 % (91.3 % and 66.7 %, respectively, P = 0.027). In stratified and multivariate analyses adjusted for age, gender, histology and tumor status, a higher LNR was associated with high pN stage and so associated with worse OS and DFS. Thus, the LNR 37 % as a cutoff point was found not to be an independent factor for predicting the one-year OS or DFS in patients with non-metastatic GC. The LNR is a prognostic factor in GC. However, no single cut-off value was determined as an independent prognostic factor.

Multivariate Logistic regression analysis of prognostic factors for stage Ⅲ rectal cancer

AIM: To analyze prognostic factors for stage Ⅲ rectal cancer by multivariate Logistic regression analysis.

METHODS: Clinical data for 198 patients with stage Ⅲ rectal cancer who underwent radical resection from June 2013 to June 2008 were analyzed retrospectively. Univariate and multivariate regression analyses were conducted to investigate the relationship of age, gender, gross type, TNM stage, lymph node metastasis, pathological type with prognosis. The patients were divided into two groups based on the extent of lymph node metastasis (33.9% as cutoff) to assess the relationship between lymph node metastasis and postoperative survival.

RESULTS: Univariate regression analysis indicated that age, TNM stage, pathological type and lymph node metastasis were factors significantly affecting prognosis of stage Ⅲ rectal cancer. Multivariate regression analysis indicated that the extent of lymph node metastasis, not age, sex, TNM stage, and pathological type, was an independent predictor of survival of patients with stage Ⅲ colorectal cancer.

CONCLUSION: Lymph node metastasis is an important predictor of prognosis of stage Ⅲ rectal cancer.

Lymph node density in oral cavity cancer: results of the International Consortium for Outcomes Research

Background:

Lymph node density (LND) has previously been reported to reliably predict recurrence risk and survival in oral cavity squamous cell carcinoma (OSCC). This multicenter international study was designed to validate the concept of LND in OSCC.

Methods:

The study included 4254 patients diagnosed as having OSCC. The median follow-up was 41 months. Five-year overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS), locoregional control and distant metastasis rates were calculated using the Kaplan–Meier method. Lymph node density (number of positive lymph nodes/total number of excised lymph nodes) was subjected to multivariate analysis.

Results:

The OS was 49% for patients with LND⩽0.07 compared with 35% for patients with LND>0.07 (P<0.001). Similarly, the DSS was 60% for patients with LND⩽0.07 compared with 41% for those with LND>0.07 (P<0.001). Lymph node density reliably stratified patients according to their risk of failure within the individual N subgroups (P=0.03). A modified TNM staging system based on LND ratio was consistently superior to the traditional system in estimating survival measures.

Conclusion:

This multi-institutional study validates the reliability and applicability of LND as a predictor of outcomes in OSCC. Lymph node density can potentially assist in identifying patients with poor outcomes and therefore for whom more aggressive adjuvant treatment is needed.