Metastatic lymph node ratio in stage III rectal cancer; prognostic significance in addition to the 7th edition of the TNM classification. Eur J Surg Oncol. 2010;36:1180-1186. [PMID: 20884164 DOI: 10.1016/j.ejso.2010.09.007]

Impact of self-expandable metallic prosthesis on lymph node dissemination in obstructive left-sided colorectal cancer

BACKGROUND

The introduction of self-expandable metal stent (SEMS) insertion in obstructive colorectal cancer (CRC) has been associated with an increased risk of tumor perforation, potentially leading to peritoneal dissemination, tumor cell spread via lymphatic vessels, perineural invasion, and peripheral bloodstream. The objective of this study was to assess the impact of SEMS placement on CRC lymph node metastasis.

METHODS

We retrospectively reviewed 48 patients with malignant colorectal obstruction treated with a temporary SEMS before elective surgery, and 51 patients with malignant colorectal obstruction who underwent elective surgery without prior SEMS placement.

RESULTS

No significant differences were found in the lymph node ratio (LNR) or in the results obtained from the logarithm of the ratio between positive and negative nodes (LODDS). Regarding recurrence, patients without SEMS had a fourfold higher risk of local recurrence compared to those with SEMS (19.6% vs. 6.3%), and a twofold higher risk of distant recurrence (31.4% vs. 14.6%). These differences were statistically significant for overall recurrence and for each local and distant recurrence individually (P = 0.02, P = 0.05, and P = 0.04, respectively).

CONCLUSION

SEMS placement in obstructive CRC not only shows the potential to suppress tumor growth, but also reduce nodal spread, as no differences in LNR and LODDS values were observed when comparing preoperative SEMS placement in patients with advanced left CRC.

Conditional survival analysis and real-time prognosis prediction in stage III T3-T4 colon cancer patients after surgical resection: a SEER database analysis

BACKGROUND

Conditional survival (CS) takes into consideration the duration of survival post-surgery and can provide valuable additional insights. The aim of this study was to investigate the risk factors associated with reduced one-year postoperative conditional survival in patients diagnosed with stage III T3-T4 colon cancer and real-time prognosis prediction. Furthermore, we aim to develop pertinent nomograms and predictive models.

METHODS

Clinical data and survival outcomes of patients diagnosed with stage III T3-T4 colon cancer were obtained from the Surveillance, Epidemiology, and End Results (SEER) database, covering the period from 2010 to 2019. Patients were divided into training and validation cohorts at a ratio of 7:3. The training set consisted of a total of 11,386 patients for conditional overall survival (cOS) and 11,800 patients for conditional cancer-specific survival (cCSS), while the validation set comprised 4876 patients for cOS and 5055 patients for cCSS. Univariate and multivariate Cox regression analyses were employed to identify independent risk factors influencing one-year postoperative cOS and cCSS. Subsequently, predictive nomograms for cOS and cCSS at 2-year, 3-year, 4-year, and 5-year intervals were constructed based on the identified prognostic factors. The performance of these nomograms was rigorously assessed through metrics including the concordance index (C-index), calibration curves, and the area under curve (AUC) derived from the receiver operating characteristic (ROC) analysis. Clinical utility was further evaluated using decision curve analysis (DCA).

RESULTS

A total of 18,190 patients diagnosed with stage III T3-T4 colon cancer were included in this study. Independent risk factors for one-year postoperative cOS and cCSS included age, pT stage, pN stage, pretreatment carcinoembryonic antigen (CEA) levels, receipt of chemotherapy, perineural invasion (PNI), presence of tumor deposits, the number of harvested lymph nodes, and marital status. Sex and tumor site were significantly associated with one-year postoperative cOS, while radiation therapy was notably associated with one-year postoperative cCSS. In the training cohort, the developed nomogram demonstrated a C-index of 0.701 (95% CI, 0.711-0.691) for predicting one-year postoperative cOS and 0.701 (95% CI, 0.713-0.689) for one-year postoperative cCSS. Following validation, the C-index remained robust at 0.707 (95% CI, 0.721-0.693) for one-year postoperative cOS and 0.700 (95% CI, 0.716-0.684) for one-year postoperative cCSS. ROC and calibration curves provided evidence of the model's stability and reliability. Furthermore, DCA underscored the nomogram's superior clinical utility.

CONCLUSIONS

Our study developed nomograms and predictive models for postoperative stage III survival in T3-T4 colon cancer with the aim of accurately estimating conditional survival. Survival bias in our analyses may lead to overestimation of survival outcomes, which may limit the applicability of our findings.

Post-Chemoradiation Metastatic, Persistent and Resistant Nodes in Locally Advanced Rectal Cancer: Metrics and Their Impact on Long-Term Outcome

BACKGROUND

The purpose of this study was to evaluate the long-term oncological progression pattern of locally advanced rectal cancer patients with post-neoadjuvant nodal metastatic disease (ypN+) and correlate potential prognostic features associated with proven radiochemoresistant nodal biology.

METHODS

Individual patient data (100 variables) from a 20-year consecutive single-institution multidisciplinary experience (1995-2015), delivering multimodal therapy to rectal cancer patient candidates for radical treatment, including a neoadjuvant component and surgical resection with or without intraoperative radiotherapy followed by optional adjuvant chemotherapy. The ypN+ disease data was registered in the context of initial staging categories post-neoadjuvant T status (ypT).

RESULTS

Data on 487 patients showed histologically confirmed diagnoses of metastatic nodal disease in 108 specimens (ypN+, 22.1). There was a significant age difference (p = 0.009) between the ypN groups: age ≥ 65 was 57.6% in pN0 and 43.5% in ypN+ and patients aged < 65 constituted 42.4% of pN0 and 56.5% of ypN+. According to the clinical stage there were statistically significant differences (p = 0.001) in the categories' distribution: ypN+ patients 10.8% were stage II and 89.2% were stage III. Univariant analysis on outcome variables showed statistically significant differences in overall survival at 7 years (63.8% vs. 55.7%, p = 0.016) disease-free survival (DFS) (78% vs. 53.8%, p = 0.000) and local recurrence-free survival (LRFS) (93.6% vs. 84%, p = 0.002).

CONCLUSIONS

The presence of nodal metastases (ypN+) after neoadjuvant therapy containing long-course pelvic irradiation severely impacts the long-term outcome for patients with locally advanced rectal cancer and correlates with multiple clinical and therapeutic variable metrics. Implementation of local and systemic therapies should be adapted and intensified in relation to the finding of ypN+ category in surgical specimens.

The Effect of Mediterranean Diet on Body Composition, Inflammatory Factors, and Nutritional Status in Patients with Cachexia Induced by Colorectal Cancer: A Randomized Clinical Trial

BACKGROUND

Along with high calorie and high protein diet, a new comprehensive dietary approach is needed to control cachexia caused by cancer and its related outcomes. This study was done to evaluate the effect of a Mediterranean diet on body composition, nutritional status, and inflammatory markers among cancer cachexia patients.

METHODS

In this randomized clinical trial, 46 patients with colorectal cancer-induced cachexia were included. After randomization, 23 patients were allocated to the intervention group (Mediterranean diet) and 23 to the control group (nutritional counseling for weight gain and prevention of weight loss in cancer patients). The primary outcome including muscle health, nutritional status, and inflammatory markers along with secondary outcomes such as quality of life, and serum proteins were evaluated at the start and the eighth week of the study. Statistical analysis was performed according to the intention-to-treat concept. To compare changes in dependent variables between the 2 groups, analysis of covariance (ANCOVA) was performed.

RESULTS

After adjustment for the baseline values, age, sex, and supplements use, in the Mediterranean diet group mean of weight (P < .001), lean body mass (P = .001), fat mass (P = .002), and muscle strength (P < .001) were significantly increased compared to the control group. Regarding inflammatory markers, the mean serum level of tumor necrosis factor-alpha (TNF-α) (P < .001), high sensitive-C-reactive protein (hs-CRP) (P = .01) and Interleukin 6 (IL-6) (P < .001) were significantly improved in the Mediterranean diet group. Moreover, in the Mediterranean diet group, the score for global health status (P = .02) and physical performance score (P < .001) were significantly increased.

CONCLUSION

It appears that the implementation of the Mediterranean diet might be a strategy to improve nutritional status, quality of life, inflammatory markers, and body composition in patients with colorectal cancer cachexia.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (www.irct.ir); ID: IRCT20211027052884N1.

The effect of Mediterranean diet on nutritional status, muscle mass and strength, and inflammatory factors in patients with colorectal cancer-induced cachexia: study protocol for a randomized clinical trial

Background

Current dietary strategies to manage cancer cachexia and the relevant outcomes did not provide a comprehensive solution. This study will evaluate the effect of a Mediterranean diet on inflammatory markers, nutritional status, muscle mass, and strength among patients with cancer cachexia (CC).

Methods

This will be a randomized clinical trial involving men and women diagnosed with localized or advanced colorectal cancer-induced cachexia. In total, 40 patients with CC will be recruited based on inclusion criteria and then these patients will be randomly allocated to receive either a Mediterranean diet (n = 20) or only routine nutritional advice (n = 20) for 8 weeks. The primary outcome will be nutritional status, muscle mass and strength, and serum concentrations of inflammatory markers including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and high-sensitive C-reactive protein (hs-CRP). Moreover, we will consider serum albumin and total protein levels, complete blood count (CBC), and quality of life as the secondary outcomes. All outcomes will be measured at the beginning and end (the eighth week) of the study. We will assess participants’ adherence to the prescribed diets by using a 1-day food record in the second, fourth, sixth, and eighth weeks of the study.

Discussion

Along with adequate calorie and protein intake in cancer cachexia, reducing inflammatory cytokines might be a useful strategy for maintaining nutritional status and body composition. Mediterranean diet has been shown to have anti-inflammatory properties, and by its components, it might help patients with cachexia to have a better nutritional status and quality of life.

Trial registration

Iranian Registry of Clinical Trials (www.irct.ir) RCT20211027052884N1. Prospectively registered on November 09, 2021.

Lymph node yield less than 12 is not a poor predictor of survival in locally advanced rectal cancer after laparoscopic TME following neoadjuvant chemoradiotherapy

Purpose

Previous studies have confirmed that neoadjuvant chemoradiotherapy (nCRT) may reduce the number of lymph nodes retrieved in rectal cancer. However, it is still controversial whether it is necessary to harvest at least 12 lymph nodes for locally advanced rectal cancer (LARC) patients who underwent nCRT regardless of open or laparoscopic surgery. This study was designed to evaluate the relationship between lymph node yield (LNY) and survival in LARC patients who underwent laparoscopic TME following nCRT.

Methods

Patients with LARC who underwent nCRT followed by laparoscopic TME were retrospectively analyzed. The relationship between LNY and survival of patients was evaluated, and the related factors affecting LNY were explored. To further eliminate the influence of imbalance of clinicopathological features on prognosis between groups, propensity score matching was conducted.

Results

A total of 257 consecutive patients were included in our study. The median number of LNY was 10 (7 to 13) in the total cohort. There were 98 (38.1%) patients with 12 or more lymph nodes harvested (LNY ≥12 group), and 159 (61.9%) patients with fewer than 12 lymph nodes retrieved (LNY <12 group). There was nearly no significant difference between the two groups in clinicopathologic characteristics and surgical outcomes except that the age of LNY <12 group was older (P<0.001), and LNY <12 group tended to have more TRG 0 cases (P<0.060). However, after matching, when 87 pairs of patients obtained, the clinicopathological features were almost balanced between the two groups. After a median follow-up of 65 (54 to 75) months, the 5-year OS was 83.9% for the LNY ≥12 group and 83.6% for the LNY <12 group (P=0.893), the 5-year DFS was 78.8% and 73.4%, respectively (P=0.621). Multivariate analysis showed that only patient age, TRG score and ypN stage were independent factors affecting the number of LNY (all P<0.05). However, no association was found between LNY and laparoscopic surgery-related factors.

Conclusions

For LARC patients who underwent nCRT followed by laparoscopic TME, the number of LNY less than 12 has not been proved to be an adverse predictor for long-term survival. There was no correlation between LNY and laparoscopic surgery-related factors.

Prognostic value of lymph node ratio in resectable rectal cancer after preoperative short-course radiotherapy-results from randomized clinical trial

PURPOSE

The value of the lymph node ratio (LNR) in patients with rectal cancer has not yet been unequivocally established. This study aims to assess the effect of the lymph node ratio on the prognosis of rectal cancer in patients operated after short-course preoperative 25 Gy radiotherapy, at 10-year follow-up.

METHODS

This is a substudy based on data from a prospective randomized clinical trial. A total of 141 patients with resectable rectal cancer were included. Lymph node yield was compared in patients with short and long time intervals between radiotherapy and surgery. Survival curves were compared between patients with different ypN and LNR categories. Univariate and multivariate analyses were performed to identify independent prognostic factors for overall survival and disease-free survival.

RESULTS

Survival and recurrence data were available for a median follow-up of 11.6 years. The lymph node yield did not differ significantly between the patients in the short- and long-interval groups. A greater difference in 10-year survival was observed in patients with LNR ≤ 0.41 and > 0.41 when compared to the ypN categories. Separate prognostic factor analyses were performed for the entire population and for subgroups that had < 12 and 12 lymph nodes resected. LNR was identified as an independent prognostic factor for overall survival, in multivariate analyses, for all patients and those with less than 12 retrieved lymph nodes.

CONCLUSION

The lymph node yield is comparable in patients with different time intervals between radiation therapy and surgery. LNR better discriminates patients in terms of overall survival than ypN categories.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT01444495, date of registration: September 30, 2011.

Incremental Value of Radiomics in 5-Year Overall Survival Prediction for Stage II-III Rectal Cancer

Although rectal cancer comprises up to one-third of colorectal cancer cases and several prognosis nomograms have been established for colon cancer, statistical tools for predicting long-term survival in rectal cancer are lacking. In addition, previous prognostic studies did not include much imaging findings, qualitatively or quantitatively. Therefore, we include multiparametric MRI information from both radiologists' readings and quantitative radiomics signatures to construct a prognostic model that allows 5-year overall survival (OS) prediction for advance-staged rectal cancer patients. The result suggested that the model combined with quantitative imaging findings might outperform that of conventional TNM staging or other clinical prognostic factors. It was noteworthy that the identified radiomics signature consisted of three from dynamic contrast-enhanced (DCE)-MRI, four from anatomical MRI, and one from functional diffusion-weighted imaging (DWI). This highlighted the importance of multiparametric MRI to address the issue of long-term survival estimation in rectal cancer. Additionally, the constructed radiomics signature demonstrated value to the conventional prognostic factors in predicting 5-year OS for stage II-III rectal cancer. The presented nomogram also provides a practical example of individualized prognosis estimation and may potentially impact treatment strategies.

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.

Prognostic importance of lymph node count and ratio in rectal cancer after neoadjuvant chemoradiotherapy: Results from a cross-sectional study

BACKGROUND

The aim of this study was to determine the prognostic value of lymph node count (LNC) and lymph node ratio (LNR) in rectal cancer after neoadjuvant chemoradiotherapy (CRT).

METHODS

Patients who underwent neoadjuvant CRT and total mesorectal excision (TME) for Stage I-III rectal cancer were selected from a cross-sectional study including 71 Dutch centres. Primary outcome parameters were disease-free survival (DFS) and overall survival (OS). Prognostic significance of LNC and LNR (cut-off values 0.15, 0.20, 0.30) was tested for different (sub)groups.

RESULTS

From 2095 registered patients, 458 were included, of which 240 patients with LNC < 12 and 218 patients with LNC ≥ 12. LNC was not significantly associated with DFS (p = 0.35) and OS (p = 0.59). In univariable analysis, LNR was significantly associated with DFS and OS in the whole cohort and LNC subgroups, but not in multivariable analysis.

CONCLUSIONS

LNC was not associated with long-term oncological outcome in rectal cancer patients treated with CRT, nor was LNR when corrected for N-stage. However, LNR might be used to identify subgroups of node-positive patients with a favourable outcome.

Lymph Node Ratio as a Prognostic Marker in Rectal Cancer Survival: A Systematic Review and Meta-Analysis

Introduction 

The lymph node ratio (LNR) is defined as the ratio of the number of positive lymph nodes to the total number of nodes retrieved. LNR has recently emerged as a prognostic factor in rectal cancer. The objective of our study was to pool eligible studies to elucidate the prognostic role of LNR on overall survival (OS) and disease-free survival (DFS) in rectal cancer patients using a meta-analysis.

Methods

A systematic database search was performed in MEDLINE and Embase for relevant studies that reported LNR in rectal cancer. Two authors independently screened the relevant articles for selection and data extraction. As a result, a list of such studies and references, published in English up to December 2019, was obtained, and a total of 4,486 node-positive patients in 18 studies were included in this meta-analysis. RevMan software 5.3 (Cochrane Collaboration, the Nordic Cochrane Centre, Copenhagen) was used for conducting all statistical analyses.

Results

A higher LNR was significantly correlated with worse OS [hazard ratio (HR): 2.60; 95% confidence interval (CI): 2.21-3.06; p≤.00001] and DFS (HR: 2.43; 95% CI: 2.11-2.80; p≤.00001) in node-positive rectal cancer patients. Besides, LNR is an independent predictive and prognostic marker of OS and DFS (HR: 2.52; 95% CI: 2.17-2.94; p≤.00001 with I²=0%; p=.32 and HR: 2.63; 95% CI: 2.17-3.18; p≤.00001 with I²=0%; p=.63 respectively, irrespective of lymph nodal harvest).

Conclusions

Our present study demonstrates that LNR is an independent predictor of survival in rectal cancer. LNR should be considered as a parameter in future oncological staging systems. Further well-designed randomized control trials to prospectively assess LNR as an independent predictor of rectal cancer survival are necessary before its application in daily practice.

Survival nomograms for stage III colorectal cancer

The postoperative survival of patients with stage III colorectal cancer (CRC) various obviously. We sought to develop novel nomograms for predicting the survival of these patients after radical surgery and postoperative chemotherapy.A total of 620 consecutive patients with stage III CRC who underwent curative resection and postoperative chemotherapy between January 2009 and December 2015 were retrospectively collected and randomly allocated to the training (n = 372) or validation cohort (n = 248). Clinicopathological factors were collected and analyzed. On the basis of data from 372 patients in the training set, predictive factors for overall survival (OS) and disease-free survival (DFS) were identified using multivariate Cox regression and used to construct nomograms. The predictive performance of the nomograms was assessed by concordance index (C-index) and calibration plots. An external cohort of 248 patients was used to validate the nomograms. Furthermore, nomogram performance was compared with the performance of T and N stage stratification.Tumor differentiation grade, lymph node metastasis ratio, intravascular emboli (IVE), preoperative serum carcinoembryonic antigen (CEA) level, albumin to globulin ratio (AGR), T stage and N stage were significant prognostic factors for OS on multivariate analysis; whereas, Tumor differentiation grade, lymph node metastasis ratio, IVE, AGR and N stage were significant for DFS. Nomograms to predict 3- and 5-year OS and DFS were established that performed well (C-indexes of 0.734 [95% CI, 0.691-0.779] for OS and 0.699 [95% CI, 0.657-0.740] for DFS prediction), and nomogram accuracy was confirmed in the validation cohort. Furthermore, model comparison proved that the nomograms were superior to risk stratification by T and N stage for stage III CRC.We propose 2 practical nomograms for stage III CRC patients that provide more accurate prognostic predictions and should be helpful for guiding individualized treatment and postoperative surveillance.

Lymph node yield in right colectomy for cancer: a comparison of open, laparoscopic and robotic approaches

AIM

Studies have demonstrated a relationship between lymph node (LN) yield and survival after colectomy for cancer. The impact of surgical technique on LN yield has not been well explored.

METHOD

This is a retrospective study of right colectomy (RC) for cancer at a single institution from 2012 to 2014. Exclusion criteria were previous colectomy and emergent and palliative operations. All data were collected by chart review. Primary outcomes were LN yield and the LN to length of surgical specimen (LN-LSS) ratio. Multivariable mixed models were created with surgeon and pathologist as random effects. Sensitivity analyses were performed to exclude Stage IV cancers and to analyse groups on an 'as-treated' basis.

RESULTS

We identified 181 open (O-RC), 163 laparoscopic (L-RC) and 119 robotic (R-RC) right colectomies. O-RC was more commonly performed in women with metastatic disease. The mean LN yield was 28, 29 and 34 in O-RC, L-RC and R-RC, respectively; the respective mean LN-LSS ratios were 0.83, 0.91 and 1.0. The R-RC approach produced a higher LN yield than the other approaches (P < 0.01), and a higher LN-LSS ratio than O-RC (P < 0.01). These findings were unchanged in sensitivity analyses.

CONCLUSION

Robotic right colectomy improves LN yield and the LN-LSS ratio, which may reflect better mesocolic excision. The effect of these findings on survival requires further investigation.

Novel predictors for lymph node metastasis in submucosal invasive colorectal carcinoma

AIM

To evaluate a novel grading system to predict lymph node metastasis (LNM) in patients with submucosal invasive colorectal carcinoma (SICRC).

METHODS

We analyzed the associations between LNM and various clinicopathological features in 252 patients with SICRC who had undergone radical surgery at the Seoul Saint Mary’s hospital between 2000 and 2015.

RESULTS

LNM was observed in 31 patients (12.3%). The depth and width of the submucosal invasion, lymphatic invasion, tumor budding, and the presence of poorly differentiated clusters (PDCs) were significantly associated with the incidence of LNM. Using multivariate analysis, the receiver operating characteristic curvewas calculated and the area under curve (AUC) was used to compare the ability of the different parameters to identify the risk of LNM. The most powerful clinicopathological parameter for predicting LNM was lymphatic invasion (difference AUC = 0.204), followed by the presence or absence of tumor budding (difference AUC = 0.190), presence of PDCs (difference AUC = 0.172) and tumor budding graded by the Ueno method (difference AUC = 0.128).

CONCLUSION

Our results indicate that the tumor budding and the depth multiplied by the width measurements of submucosal invasion can provide important information for patients with SICRC.

Increased lymph node retrieval decreases adjuvant chemotherapy rate for stage II colon cancer

OBJECTIVE

Investigation of lymph nodes in colorectal specimens after surgery due to cancer is important for staging the cancer. There has to be an adequate number of lymph nodes to conclude a node-negative status. Our aim was to investigate if change in fixative could give increased lymph node yield, and if this could result in a potential decrease of adjuvant treatment for stage II patients. In addition, we wanted to evaluate if the change in fixative could potentially affect subsequent molecular testing.

MATERIAL AND METHODS

All resection specimens from one hospital were from 2011 fixed in GEWF while resection specimens from two other hospitals were fixed in conventional buffered formalin. Number of lymph nodes harvested were compared from two periods; 2009/2010 and 2012/2013. In addition, tumors fixed in GEWF and tumors fixed in formalin were tested separately with immunohistochemical staining and molecular testing.

RESULTS

There was a significant increase in lymph node retrieval in specimens fixed in GEWF compared to number of lymph nodes found before the implementation of this fixative (p < 0.001). For hospitals using only formalin, the number of nodes did not increase significantly. Number of positive lymph nodes did not increase. Immunohistochemical staining can be a problem with tumors fixed in GEWF, but DNA quality seems not affected by the changes.

CONCLUSIONS

GEWF enhances lymph node detection in colorectal cancer specimens, leading to fewer patients being falsely defined as high-risk stage II. The loss of stability when staining for MMR-proteins can be overcome by molecular analysis when needed.

Lymph node ratio and surgical quality are strong prognostic factors of rectal cancer: results from a single referral centre

AIM

Nodal stage is a strong prognostic factor of oncological outcome of rectal cancer. To compensate for the variation in total number of harvested nodes, calculation of the lymph node ratio (LNR) has been advocated. The aim of the study was to compare the impact, on the long-term oncological outcome, of the LNR with other predictive factors, including the quality of total mesorectal excision (TME) and the state of the circumferential resection margin.

METHOD

Consecutive patients having elective surgery for nonmetastatic rectal cancer were extracted from a prospectively maintained database. Retrospective uni- and multivariate analyses were performed based on patient-, surgical- and tumour-related factors. The prognostic value of the LNR on overall survival (OS) and on overall recurrence-free survival (ORFS) was assessed and a cut-off value was determined.

RESULTS

From 1998 to 2013, out of 456 patients, 357 with nonmetastatic disease were operated on for rectal cancer. Neoadjuvant radiochemotherapy was administered to 66.7% of the patients. The mean number of lymph nodes retrieved was 12.8 ± 8.78 per surgical specimen. A lower lymph node yield was obtained in patients who received neoadjuvant chemoradiotherapy (11.8 vs 14.2; P = 0.014). The 5-year ORFS was 71.8% and the 5-year OS was 80.1%. Multivariate analysis confirmed LNR, the quality of TME and age to be independent prognostic factors of OS. LNR, age and perineural infiltration were independently associated with ORFS. Low- and high-risk patients could be discriminated using an LNR cut-off value of 0.2.

CONCLUSION

LNR is an independent prognostic factor of OS and ORFS. In line with the principles of optimal surgical management, the quality of TME and lymph node yield are essential technical requirements.

Nodal metastases in thyroid cancer: prognostic implications and management

The significance of cervical lymph node metastases in differentiated thyroid cancer has been controversial and continues to evolve. Current staging systems consider nodal metastases to confer a poorer prognosis, particularly in older patients. Increasingly, the literature suggests that characteristics of the metastatic lymph nodes such as size and number are also prognostic. There is a growing trend toward less aggressive treatment of low-volume nodal disease. The aim of this review is to summarize the current literature and discuss prognostic and management implications of lymph node metastases in differentiated thyroid cancer.

Prognostic Value of Lymph Node Ratio in Locally Advanced Rectal Cancer Patients After Preoperative Chemoradiotherapy Followed by Total Mesorectal Excision

Although the absolute number of positive lymph nodes (LNs) has been established as 1 of the most important prognostic factors in rectal cancers, many researchers have proposed that the lymph node ratio (LNR) may have better predicted outcomes. We conducted a retrospective study to compare the predictive ability of LNR and ypN category in rectal cancer. A total of 264 locally advanced rectal cancer (LARC) patients who underwent preoperative chemoradiotherapy (CRT) followed by total mesorectal excision (TME) between 2005 and 2012 were reviewed. All patients were categorized into 3 groups or patients with metastatic LNs were categorized into 2 groups according to the LNR. The prognostic effect on overall survival (OS) and disease-free survival (DFS) was evaluated. With a median follow-up of 45 months, the OS and DFS were 68.4% and 59.3% for the entire cohort, respectively. The respective 5-year OS and DFS rates for the 3 groups (LNR = 0, 0 < LNR ≤ 0.20, and 0.20 < LNR ≤ 1.0) were as follows: 83.2%, 72.6%, and 49.4% (P < 0.001) and 79.5%, 57.3%, and 33.5% (P < 0.001), respectively. Multivariate analysis revealed that LNR and differentiation, but not the number of positive LNs, had independent prognostic value for OS (hazard ratio [HR] = 2.328, 95% confidence interval [CI]: 1.850-4.526, P < 0.001) and DFS (HR = 3.004, 95% CI: 1.616-5.980, P < 0.001). As for patients with positive LNs, the respective 5-year OS and DFS rates for the 2 groups (0 < LNR ≤ 0.20, and 0.20 < LNR ≤ 1.0) were 72.6% and 49.4% (P < 0.001) and 57.3% and 33.5% (P < 0.001), respectively. Multivariate analysis revealed that only LNR was an independent factor for OS (HR = 3.214, 95% CI: 1.726-5.986, P < 0.001) and DFS (HR = 4.230, 95% CI: 1.825-6.458, P < 0.001). Subgroups analysis demonstrated that the ypN category had no impact on survival whereas increased LNR was a significantly prognostic indicator for worse survival in the LNs < 12 subgroup. LNR is an independent prognostic factor in LARC patients treated with preoperative CRT followed by TME. It may be a better independent staging method than the number of metastatic LNs when <12 LNs are harvested after preoperative CRT.

Prognostic value of lymph node ratio in survival of patients with locally advanced rectal cancer

BACKGROUND

The lymph node ratio (LNR) has been shown to be an important prognostic factor in patients with gastric, breast, pancreatic and colorectal cancer. We investigated the prognostic impact of the LNR in addition to TNM classification in patients with locally advanced rectal cancer.

METHODS

We retrospectively analyzed patients who underwent curative resection for locally advanced rectal cancer between July 2005 and December 2010. We determined the LNR cutoff value using a receiver operating characteristic curve. The Kaplan-Meier method was used to estimate survival curves, while Cox regression analyses were used to evaluate the relationship between LNR and survival.

RESULTS

We included 180 patients aged 28-83 years with median follow-up of 41.8 months. The median number of lymph nodes examined and lymph nodes involved were 11.5 and 4, respectively, and the median LNR was 0.366. An LNR of 0.19 (19%) was the cutoff point to separate patients with regard to median overall survival. Median overall survival was 64.2 months for patients with an LNR of 0, 59.1 for an LNR of 0.19 or less and 37.6 for an LNR greater than 0.19 (p = 0.004). The median disease-free survival was 32.9 months for patients with an LNR of 0, 30.4 for an LNR of 0.19 or less and 17.8 for an LNR greater than 0.19 (p = 0.002).

CONCLUSION

Our results suggest that LNR should be considered an additional prognostic factor in patients with locally advanced rectal cancer.

Pathologic Assessment of Rectal Carcinoma after Neoadjuvant Radio(chemo)therapy: Prognostic Implications

Neoadjuvant radio(chemo)therapy is increasingly used in rectal cancer and induces a number of morphologic changes that affect prognostication after curative surgery, thereby creating new challenges for surgical pathologists, particularly in evaluating morphologic changes and tumour response to preoperative treatment. Surgical pathologists play an important role in determining the many facets of rectal carcinoma patient care after neoadjuvant treatment. These range from proper handling of macroscopic specimens to accurate microscopic evaluation of pathological features associated with patients' prognosis. This review presents the well-established pathological prognostic indicators and discusses challenging features in order to provide both surgical pathologists and treating physicians with a checklist that is useful in a neoadjuvant setting.

Preoperative endoscopic tattooing to mark the tumour site does not improve lymph node retrieval in colorectal cancer: a retrospective cohort study

BACKGROUND

A direct correlation between number of lymph nodes retrieved and evaluated after a colectomy for colorectal cancer and survival of the patient has been reported, and consensus guidelines recommend to assess at least 12 lymph nodes for adequate staging. Many factors (i.e., patients' and tumour characteristics, surgeon, and pathologist) may influence the evaluation of the presence of neoplastic disease in lymph nodes as well as the total number of lymph nodes examined. Preoperative endoscopic tattooing to mark the site of the tumour has recently been suggested to facilitate the retrieval of lymph nodes in colorectal specimens. The aim of this study was to investigate its association with adequate lymphadenectomy (≥12 nodes) after colorectal resection for cancer.

RESULTS

All patients undergoing elective colorectal resection for cancer between 2009 and 2011 at the S. Anna University Hospital in Ferrara, Italy (N = 250) were retrospectively divided into two cohorts according to whether ink tattooing to mark the tumour site was performed during preoperative colonoscopy. The two cohorts were comparable regarding age, gender, body mass index, tumour location and size, TNM staging, and DNA microsatellite instability-high status. No difference between the tattoo (N = 107) and control (N = 143) groups could be detected in the rate of adequate lymphadenectomies performed (78% vs. 79%, p = 0.40). All factors known to influence lymph nodes retrieval from colorectal specimen were specifically evaluated. Rectal and colonic cancers were analysed together and separately. Full adjusted logistic regression analysis in patients who underwent colonic resection showed that right hemicolectomy (OR 4.72; CI95% 1.09-20.36) was the only factor associated to adequate lymphadenectomy. No association between ink tattooing performed preoperatively to mark the site of the tumour and adequate lymphadenectomy after colorectal resection was found with logistic regression analysis.

CONCLUSION

This study shows that preoperative ink tattooing utilized to mark the site of the tumour does not improve adequate lymphadenectomy and lymph nodes yield from colorectal cancer specimens. Further studies are therefore needed to determine if preoperative colonoscopic tattooing to mark the tumour site can refine staging.

Lymph node ratio predicts tumor recurrence in stage III colon cancer

OBJECTIVE

To evaluate the lymph node ratio as a predictor for tumor recurrence in stage III colon cancer patients.

METHODS

Patients with stage III colon cancer who underwent curative resection between January 2005 and December 2010 were retrospectively reviewed. The main outcomes were tumor recurrence and death. The impact of lymph node ratio and other clinicopathological factors on disease-free survival were evaluated by uni- and multivariate analysis. Receiver operator characteristic (ROC) analysis was conducted in order to identify the best cutoff value for lymph node ratio to predict tumor recurrence. Disease-free survival was estimated by the Kaplan-Meier method.

RESULTS

Seventy patients were included in the study (50% male). The mean age was 64 years. Univariate analysis identified four factors for tumor recurrence: carcinoembryonic antigen, N stage, number of positive lymph nodes and lymph node ratio. Lymph node ratio was the one with the greatest magnitude of association. Receiver operator characteristic analyzes identified 0.15 as the best cutoff value. Patients with a lymph node ratio < 0.15 had a disease-free survival of 90% in 3 years (versus 64%, p = 0.011).

CONCLUSION

Lymph node ratio is a strong predictor for tumor recurrence in stage III colon cancer.

KRAS gene mutation in a series of unselected colorectal carcinoma patients with prognostic morphological correlations: a pyrosequencing method improved by nested PCR

INTRODUCTION

Inhibition of EGFR is a strategy for treating metastatic colorectal cancer (CRC) patients. KRAS sequencing is mandatory for selecting wild-type tumor patients who might benefit from this treatment. DNA from formalin-fixed paraffin-embedded (FFPE) tissues is commonly used for routine clinical detection of mutations, and its amplification succeeds only when all preanalytical histological processes have been controlled. In cases that are not properly processed, the DNA results can be poor, with low peak pyrosequencing findings. We designed and tested a pair of forward and reverse primers for a nested PCR method, followed by pyrosequencing, in a single Latin American institution series of 422 unselected CRC patients, correlating KRAS mutations with pathological and clinical data.

MATERIALS AND METHODS

Patient DNA samples from tumors were obtained by scraping or laser microdissection of cells from FFPE tissue and extracted using a commercial kit. DNA was first amplified by PCR using 2 primers that we designed; then, nested PCR was performed with the amplicon from the preamplification PCR using the KRAS PyroMark™ Q96 V2.0 kit (Qiagen). Pathological data were retrieved from pathology reports.

RESULTS

KRAS mutation was observed in 33% of 421 cases. Codon 12 was mutated in 76% of cases versus codon 13 in 24%. Right-sided CRCs harbored more KRAS mutations than left-sided tumors, as did tumors that presented with perineural invasion.

CONCLUSION

Our findings in this Latin American population are consistent with the literature regarding the frequency of KRAS mutations in CRC, their distribution between codons 12 and 13, and type of nucleotide substitution. By combining nested PCR and pyrosequencing, we achieved a high rate of conclusive results in testing KRAS mutations in CRC samples - a method that can be used as an ancillary test for failed assays by conventional PCR.

Lateral Neck Lymph Node Characteristics Prognostic of Outcome in Patients with Clinically Evident N1b Papillary Thyroid Cancer

PURPOSE

To identify lateral lymph node (LN) characteristics predictive of outcome in papillary thyroid cancer patients with clinically evident nodal disease.

METHODS

A total of 438 patients with lateral neck metastases from papillary thyroid cancer were identified from an institutional database of 3,664 differentiated thyroid cancers. The number of positive LNs, size of the largest LN, number of positive LNs to total number of LNs removed (LN burden), and presence of extranodal spread (ENS) were recorded. Cutoffs for continuous variables were determined by receiver operating characteristic curves. LN variables predictive of recurrence free survival and disease-specific survival (DSS) were identified by the Kaplan-Meier method and the Cox proportional hazard model.

RESULTS

The median age was 41 years (range 5-86 years). The median follow-up was 65 months (range 1-332 months). Fifty-nine patients developed disease recurrence; these were local in five, regional in 40, and distant in 30 patients. Fifteen patients died of disease. Receiver operating characteristic cutoffs were >10 positive LNs and a LN burden >17 %. No lateral LN characteristics were predictive of DSS. In patients <45 years old, univariate predictors of recurrence were >10 positive nodes (p = 0.049) and LN burden >17 % (p < 0.001). In patients ≥45 years old, >10 positive nodes, LN burden >17 %, and presence of ENS were predictive of recurrence (p = 0.019, p = 0.019, and p = 0.029, respectively).

CONCLUSIONS

LN burden >17 % (1 positive LN in 6 LNs removed) in the lateral neck is predictive for recurrence in patients of all ages, whereas ENS is also prognostic for recurrence in older patients.

A systematic review of outcome reporting in colorectal cancer surgery

AIM

Evaluation of surgery for colorectal cancer (CRC) is necessary to inform clinical decision-making and healthcare policy. The standards of outcome reporting after CRC surgery have not previously been considered.

METHOD

Systematic literature searches identified randomized and nonrandomized prospective studies reporting clinical outcomes of CRC surgery. Outcomes were listed verbatim, categorized into broad groups (outcome domains) and examined for a definition (an appropriate textual explanation or a supporting citation). Outcome reporting was considered inconsistent if results of the outcome specified in the methods were not reported. Outcome reporting was compared between randomized and nonrandomized studies.

RESULTS

Of 5644 abstracts, 194 articles (34 randomized and 160 nonrandomized studies) were included reporting 766 different clinical outcomes, categorized into seven domains. A mean of 14 ± 8 individual outcomes were reported per study. 'Anastomotic leak', 'overall survival' and 'wound infection' were the three most frequently reported outcomes in 72, 60 and 44 (37.1%, 30.9% and 22.7%) studies, respectively, and no single outcome was reported in every publication. Outcome definitions were significantly more often provided in randomized studies than in nonrandomized studies (19.0% vs 14.9%, P = 0.015). One-hundred and twenty-seven (65.5%) papers reported results of all outcomes specified in the methods (randomized studies, n = 21, 61.5%; nonrandomized studies, n = 106, 66.2%; P = 0.617).

CONCLUSION

Outcome reporting in CRC surgery lacks consistency and method. Improved standards of outcome measurement are recommended to permit data synthesis and transparent cross-study comparisons.

Complete pathological responses in locally advanced rectal cancer after preoperative IMRT and integrated-boost chemoradiation

BACKGROUND AND PURPOSE

To analyze the efficacy and safety of a new preoperative intensity-modulated radiotherapy (IMRT) and integrated-boost chemoradiation scheme.

PATIENTS AND METHODS

In all, 74 patients were treated with IMRT and concurrent standard dose capecitabine. The dose of the planning target volume (PTV) encompassing the tumor, mesorectum, and pelvic lymph nodes was 46 Gy in 23 fractions; the boost PTV, at a dose of 57.5 Gy in 23 fractions, included the macroscopic primary tumor and pathological lymph nodes. The patients underwent surgery 6-8 weeks after chemoradiation.

RESULTS

The complete treatment data of 72 patients were analyzed. Tumor downstaging was achieved in 55 patients (76.38 %) and node downstaging in 34 (47.2 %). In 22 patients (30.6 %), there was complete pathological response (ypCR). The circumferential resection margin was free of tumor in 70 patients (97.2 %). The 3-year estimated overall survival and disease-free survival rates were 95.4 and 85.9 % respectively, and no local relapse was found; however, ten patients (13.8 %) developed distant metastases. High pathologic tumor (pT) downstaging was shown as a favorable prognostic factor for disease-free survival. No grade 4 acute radiotherapy-related toxicity was found.

CONCLUSIONS

The IMRT and integrated-boost chemoradiation scheme offered higher rates of ypCR and pT downstaging, without a significant increase in toxicity. The circumferential margins were free of tumors in the majority of patients. Primary tumor regression was associated with better disease-free survival.

The prognostic value of lymph node ratio and updated TNM classification in rectal cancer patients with adequate versus inadequate lymph node dissection

BACKGROUND

The aim of this study was to clarify whether the lymph node ratio (LNR) is superior to the updated TNM classification regarding the prognosis of stage III rectal cancer patients who have not undergone neoadjuvant therapy. The TNM system is based on the absolute number of lymph nodes involved, and the LNR takes into account involved and examined nodes.

METHODS

In 237 patients with stage III rectal cancer, we evaluated prognostic factors for 5-year overall survival (OS), disease-free survival (DFS), and risk of distant metastases (DM) using the Kaplan-Meier method, with patients divided based on adequate versus inadequate lymph node dissection (≥12 vs. <12 lymph nodes examined). The updated TNM divides patients into four groups (1, 2-3, 4-6, and ≥7 involved nodes), while LNR divides patients into quartiles. Multivariate Cox regression analyses were performed.

RESULTS

Among patients with adequate lymph node dissection, the distributions within the two systems were in agreement in 141/178 (79.2 %, kappa 0.721), and the predictive values for OS, DFS, and DM were similar. In patients with inadequate lymph node dissection, the classifications of both systems were concordant in only 13/59 (22 %, kappa 0.021). The pN system significantly under-staged patients, while the LNR classification was a better predictor of OS, DFS, and DM.

CONCLUSIONS

In patients with adequate lymph node dissection, LNR staging does not add substantial information to the predictions of updated TNM lymph node staging. However, in patients with inadequate lymph node harvesting, the LNR compensates for the under-staging of the TNM classification and provides a better estimation of prognosis than the updated TNM system.

Colorectal cancer and lymph nodes: The obsession with the number 12

Lymphadenectomy of colorectal cancer is a decisive factor for the prognostic and therapeutic staging of the patient. For over 15 years, we have asked ourselves if the minimum number of 12 examined lymph nodes (LNs) was sufficient for the prevention of understaging. The debate is certainly still open if we consider that a limit of 12 LNs is still not the gold standard mainly because the research methodology of the first studies has been criticized. Moreover many authors report that to date both in the United States and Europe the number “12” target is uncommon, not adequate, or accessible only in highly specialised centres. It should however be noted that both the pressing nature of the debate and the dissemination of guidelines have been responsible for a trend that has allowed for a general increase in the number of LNs examined. There are different variables that can affect the retrieval of LNs. Some, like the surgeon, the surgery, and the pathology exam, are without question modifiable; however, other both patient and disease-related variables are non-modifiable and pose the question of whether the minimum number of examined LNs must be individually assigned. The lymph nodal ratio, the sentinel LNs and the study of the biological aspects of the tumor could find valid application in this field in the near future.

Prognostic value of lymph node ratios in node positive rectal cancer treated with preoperative chemoradiation

BACKGROUND

To investigate the impact of the lymph node ratio (LNR) on the prognosis of patients with locally advanced rectal cancer undergoing pre-operative chemoradiation.

METHODS

Clinicopathologic and follow up data of 128 patients with stage III rectal cancer who underwent curative resection from 1996 to 2007 were reviewed. The patients were divided into two groups according to the lymph node ratio: LNR ≤ 0.2 (n=28), and >0.2 (n=100). Kaplan-Meier and the Cox proportional hazard regression models were used to evaluate the prognostic effects according to LNR.

RESULTS

Median numbers of lymph nodes examined and lymph nodes involved by tumour were 10.3 (range 2-28) and 5.8 (range 1-25), respectively, and the median LNR was 0.5 (range, 0-1.6). The 5-year survival rate significantly differed by LNR (≤ 0.2, 69%; >0.2, 19%; Log-rank p value < 0.001). LNR was also a significant prognostic factor of survival adjusted for age, sex, post-operative chemotherapy, total number of examined lymph nodes, metastasis and local recurrence (≤ 0.2, HR=1; >0.2, HR=4.8, 95%CI=2.1-11.1) and a significant predictor of local recurrence and distant metastasis during follow-up independently of total number of examined lymph node.

CONCLUSIONS

Total number of examined lymph nodes and LNR were significant prognostic factors for survival in patients with stage III rectal cancer undergoing pre-operative chemoradiotherapy.

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

Purpose

Lymph-node metastasis is the most important predictor of survival in stage III rectal cancer. The number of metastatic lymph nodes may vary depending on the level of specimen dissection and the total number of lymph nodes harvested. The aim of this study was to evaluate whether the lymph node ratio (LNR) is a prognostic parameter for patients with rectal cancer.

Methods

A retrospective review of a database of rectal cancer patients was performed to determine the effect of the LNR on the disease-free survival (DFS) and the overall survival. Of the total 228 patients with rectal cancer, 55 patients with stage III 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.

Results

According to the cutoff point 0.15 (15%), the 2-year DFS was 95.2% among patients with a LNR < 0.15 compared with 67.6% for those with LNR ≥ 0.15 (P = 0.02). In stratified and multivariate analyses adjusted for age, gender, histology and tumor status, a higher LNR was independently associated with worse DFS.

Conclusion

This study showed the prognostic significance of ratio-based staging for rectal cancer and may help in developing better staging systems. LNR 0.15 (15%) was shown to be a cutoff point for determining survival and prognosis in rectal cancer cases.

What counts most in the lymph node count for colorectal cancer?

The adequate number of lymph nodes that should be examined to correctly stage colorectal cancer is still debated. Even though the guidelines state that 12 should be the minimum, there is ongoing concern that this might not be enough. Moreover, many studies have shown that this cut-off is far from universally obtained in many surgical series, whether via laparotomy or via laparoscopy. Arguments in favor of sticking to the cutoff value of 12 are weak: certainly, culling and examining as many lymph nodes as possible should increase the chances of correct staging and the consequent therapeutic consequences, decrease local recurrence and, perhaps, also increase survival (although this is not the direct consequence of gathering and examining as many lymph nodes as possible). Laparoscopy should be no different from open surgery: the same rational prevails for laparoscopic oncologic clearance to increase patient well-being and ensure good practice. What is most important, however, is to make surgeons and pathologists realize that this issue is important and that all of us should strive, in close collaboration, to achieve these goals, for the good of the patient, the person for whom the lymph node count counts most.

The effects of preoperative chemoradiotherapy on lymph node sampling in rectal cancer

BACKGROUND

The current recommendation from the American Joint Committee on Cancer and the International Union Against Cancer is that 12 or more lymph nodes should be examined to appropriately stage rectal cancer. It is unclear if this metric is appropriate or achievable for patients who receive neoadjuvant therapy.

OBJECTIVE

The purpose of this study was to review the effects of neoadjuvant chemoradiotherapy on the lymph node yield in patients with rectal cancer.

DATA SOURCES

A comprehensive search was made of MEDLINE, PubMed, and Web of Science for articles published through December 2011.

STUDY SELECTION

The descriptors rectal neoplasms, lymph nodes, lymph node yield, radiotherapy, and neoadjuvant therapy were used to identify articles that reported the lymph node yield with and without neoadjuvant chemoradiotherapy for rectal cancer.

INTERVENTIONS

Patients received either chemoradiotherapy or no neoadjuvant treatment before undergoing total mesorectal excision for rectal cancer.

MAIN OUTCOME MEASURES

The main outcome measures included the mean lymph node yield both with and without neoadjuvant treatment, the percentage of patients that received an adequate lymph node dissection, and the number of lymph nodes found to be positive for metastatic disease.

RESULTS

A total of 7 studies were included in this review. They demonstrated a decrease in lymph node yield in patients who received neoadjuvant therapy, ranging from 7% to 53% based on the articles in this review.

LIMITATIONS

A meta-analysis was not performed because of the limited complete data published on this subject. Consequently, there is heterogeneity in the studies that were selected for this review.

CONCLUSIONS

Patients with rectal cancer who receive preoperative chemoradiotherapy should be anticipated to have a lower lymph node yield than patients who receive surgery alone. This calls into question if the current guideline of 12 lymph nodes is relevant, in particular, for those patients receiving neoadjuvant therapy.

Multimodal treatment strategies for locally advanced rectal cancer

This review outlines the important multimodal treatment issues associated with locally advanced rectal cancer. Changes to chemotherapy and radiation schema, as well as modern surgical approaches, have led to a revolution in the management of this disease but the morbidity and mortality remains high. Adequate treatment is dependent on precise preoperative staging modalities. Advances in staging via endorectal ultrasound, computed tomography, MRI and PET have improved pretreatment triage and management. Important prognostic factors and their impact for this disease are under investigation. Here we discuss the different treatment options including modern tumor-related surgical approaches, neoadjuvant as well as adjuvant therapies. Further clinical progress will largely depend on the broader implementation of multidisciplinary treatment strategies following the principles of evidence-based medicine.

Lymph node retrieval after preoperative chemoradiotherapy for rectal cancer

BACKGROUND

Current guidelines recommend the assessment of at least 12 lymph nodes for rectal cancer staging. Preoperative chemoradiotherapy may affect lymph node yield in this malignancy. This study investigated the impact of neoadjuvant chemoradiotherapy on the number of lymph nodes retrieved from rectal cancer patients.

METHODS

An analysis of 162 rectal cancer patients who underwent curative surgery between 2005 and 2010. Seventy-one patients with stage II or III tumors received preoperative chemoradiotherapy. Using multivariate analysis, we assessed the correlation between clinicopathologic variables and number of retrieved lymph nodes. We also evaluated the association between survival and number of lymph nodes obtained.

RESULTS

On multivariate analysis, preoperative chemoradiotherapy was the only variable to independently affect the number of lymph nodes obtained. The mean number of lymph nodes was 14.2 in patients treated with preoperative chemoradiotherapy and 19.4 in those not treated (P < 0.001). In the chemoradiotherapy group, 29.6 % of patients had fewer than 12 lymph nodes obtained compared with 9.9 % in the primary surgery group (P = 0.003). After chemoradiation, the number of retrieved lymph nodes was inversely correlated with tumor regression grade. Results showed that 5-year overall and disease-free survival were similar whether the patient had 12 or more nodes retrieved or not.

CONCLUSIONS

Preoperative chemoradiotherapy reduces the lymph node yield in rectal cancer. The number of retrieved lymph nodes is affected by degree of histopathologic response of the tumor to chemoradiation. Thus, number of lymph nodes should not be used as a surrogate for oncologic adequacy of resection after neoadjuvant chemoradiotherapy for rectal cancer.

Multicenter randomized phase II clinical trial comparing neoadjuvant oxaliplatin, capecitabine, and preoperative radiotherapy with or without cetuximab followed by total mesorectal excision in patients with high-risk rectal cancer (EXPERT-C)

PURPOSE

To evaluate the addition of cetuximab to neoadjuvant chemotherapy before chemoradiotherapy in high-risk rectal cancer.

PATIENTS AND METHODS

Patients with operable magnetic resonance imaging-defined high-risk rectal cancer received four cycles of capecitabine/oxaliplatin (CAPOX) followed by capecitabine chemoradiotherapy, surgery, and adjuvant CAPOX (four cycles) or the same regimen plus weekly cetuximab (CAPOX+C). The primary end point was complete response (CR; pathologic CR or, in patients not undergoing surgery, radiologic CR) in patients with KRAS/BRAF wild-type tumors. Secondary end points were radiologic response (RR), progression-free survival (PFS), overall survival (OS), and safety in the wild-type and overall populations and a molecular biomarker analysis.

RESULTS

One hundred sixty-five eligible patients were randomly assigned. Ninety (60%) of 149 assessable tumors were KRAS or BRAF wild type (CAPOX, n = 44; CAPOX+C, n = 46), and in these patients, the addition of cetuximab did not improve the primary end point of CR (9% v 11%, respectively; P = 1.0; odds ratio, 1.22) or PFS (hazard ratio [HR], 0.65; P = .363). Cetuximab significantly improved RR (CAPOX v CAPOX+C: after chemotherapy, 51% v 71%, respectively; P = .038; after chemoradiation, 75% v 93%, respectively; P = .028) and OS (HR, 0.27; P = .034). Skin toxicity and diarrhea were more frequent in the CAPOX+C arm.

CONCLUSION

Cetuximab led to a significant increase in RR and OS in patients with KRAS/BRAF wild-type rectal cancer, but the primary end point of improved CR was not met.

Lymph node ratio is an independent prognostic factor in patients with rectal cancer treated with preoperative chemoradiotherapy and curative resection

PURPOSE

To evaluate the prognostic effect of lymph node ratio (LNR) in patients with locally advanced rectal cancer who were treated with curative resection after preoperative chemoradiotherapy (CRT).

METHODS

Between October 2001 and December 2007, 519 patients who had undergone curative resection of primary rectal cancer after preoperative CRT were enrolled. Of these, 154 patients were positive for lymph node (LN) metastasis and were divided into three groups according to the LNR (≤ 0.15 [n=80], 0.16-0.3 [n=44], >0.3 [n=30]) to evaluate the prognostic effect on overall survival (OS) and disease-free survival (DFS).

RESULTS

LNR (≤ 0.15, 0.16-0.3, and >0.3) was significantly associated with 5-year OS (90.3%, 75.1%, and 45.1%; p<0.001) and DFS (66.7%, 55.8%, and 21.9%; p<0.001) rates. In a multivariate analysis, LNR (≤ 0.15, 0.16-0.3, and >0.3) was a significant independent prognostic factor for OS (hazard ratios [HRs], 1, 3.609, and 8.197; p<0.001) and DFS (HRs, 1, 1.699, and 3.960; p<0.001). LNR had a prognostic impact on OS and DFS in patients with <12 harvested LNs, as well as in those with ≥ 12 harvested LNs (p<0.05).

CONCLUSION

LNR was a significant independent prognostic predictor for OS and DFS in patients with locally advanced rectal cancer who were treated with curative resection after preoperative CRT.

Dukes C colorectal cancer: is the metastatic lymph node ratio important?

PURPOSE

Although the regional lymph node status is essential for staging of colorectal cancer, the importance of the total number of collected nodes remains controversial. Our aim was to examine the impact of the metastatic lymph node ratio (LNR) on the survival of patients with Dukes C colorectal cancer.

METHODS

All patients with Dukes C histology were selected from a prospectively collected database of all colorectal cancers resected between 1997 and 2007 at our institution. Demographic, histopathological and adjuvant treatment data were collected. The total number of positive lymph nodes was divided by the total number of lymph nodes examined to calculate the LNR. Patients were categorised into LNR groups 1 to 5 according to cut-off points: ≤0.1, 0.21, 0.36, 0.6 and ≥0.61. Survival from the date of operation was calculated using Kaplan-Meier estimates. Multivariate analysis was performed to identify those factors influencing survival.

RESULTS

Of 1,098 patients who underwent colorectal cancer resections, 41% were staged as Dukes C. Sixty-four percent of patients received chemotherapy. The median number of lymph nodes harvested and positive for tumour were 11 (range 1-52) and 4 (range 1-28), respectively. In patients who received chemotherapy, 5-year survival was 69.3% for LNR 1 and 23.6% for LNR 5. When no chemotherapy was given, the 5-year survival was 43.1% for LNR 1 and 8.7% for LNR 5.

CONCLUSIONS

Current evaluation of positive lymph nodes may not accurately stage Dukes C colorectal cancer. The assessment of the LNR is a useful prognostic method in this heterogenous group of patients.

Prognostic value of the lymph node ratio in stage III colorectal cancer

The nodal stage of colorectal cancer is based on the number of positive nodes. It is inevitably affected by the number of removed lymph nodes, but lymph node ratio can be unaffected. We investigated the value of lymph node ratio in stage III colorectal cancer in this study. The clinicopathologic factors and follow-up data of 145 cases of stage III colorectal cancer between January 1998 and December 2008 were analyzed retrospectively. The Pearson and Spearman correlation analyses were used to determine the correlation coefficient, the Kaplan-Meier method was used to analyze survival, and the Cox proportional hazard regression model was used for multivariate analysis in forward stepwise regression. We found that lymph node ratio was not correlated with the number of removed lymph nodes (r = -0.154, P = 0.065), but it was positively correlated with the number of positive lymph nodes (r = 0.739, P < 0.001) and N stage (r = 0.695, P < 0.001). Kaplan-Meier survival analysis revealed that tumor configuration, intestinal obstruction, serum carcinoembryonic antigen (CEA) concentration, T stage, N stage, and lymph node ratio were associated with disease-free survival of patients with stage III colorectal cancer (P < 0.05). Multivariate analysis showed that serum CEA concentration, T stage, and lymph node ratio were prognostic factors for disease-free survival (P < 0.05), whereas N stage failed to achieve significance (P = 0.664). We confirmed that lymph node ratio was a prognostic factor in stage III colorectal cancer and had a better prognostic value than did N stage.

Prognostic value of the lymph node ratio in stage III colorectal cancer

The nodal stage of colorectal cancer is based on the number of positive nodes. It is inevitably affected by the number of removed lymph nodes, but lymph node ratio can be unaffected. We investigated the value of lymph node ratio in stage III colorectal cancer in this study. The clinicopathologic factors and follow-up data of 145 cases of stage III colorectal cancer between January 1998 and December 2008 were analyzed retrospectively. The Pearson and Spearman correlation analyses were used to determine the correlation coefficient, the Kaplan-Meier method was used to analyze survival, and the Cox proportional hazard regression model was used for multivariate analysis in forward stepwise regression. We found that lymph node ratio was not correlated with the number of removed lymph nodes (r = -0.154, P = 0.065), but it was positively correlated with the number of positive lymph nodes (r = 0.739, P < 0.001) and N stage (r = 0.695, P < 0.001). Kaplan-Meier survival analysis revealed that tumor configuration, intestinal obstruction, serum carcinoembryonic antigen (CEA) concentration, T stage, N stage, and lymph node ratio were associated with disease-free survival of patients with stage III colorectal cancer (P < 0.05). Multivariate analysis showed that serum CEA concentration, T stage, and lymph node ratio were prognostic factors for disease-free survival (P < 0.05), whereas N stage failed to achieve significance (P = 0.664). We confirmed that lymph node ratio was a prognostic factor in stage III colorectal cancer and had a better prognostic value than did N stage.

Estimating underreported N2 disease in rectal cancer patients with low lymph node counts

BACKGROUND

The variability in the number of lymph nodes examined needs to be taken into account for adequate staging. The definition of nodal staging was refined by quantifying the likelihood of N2 disease when the patient had fewer than four positive LN.

METHODS

In a retrospective study a total of 548 patients with node positive rectal cancer and curative surgery between 1990 and 2006 were identified. The misclassification of pN staging was estimated with a Bayesian computation. The prognostic value of the calculated probability, lymph node ratio (LNR), and nodal stage was assessed with Cox proportional hazard regression.

RESULTS

A probability of understaging of 40% or more indicated worse prognosis of cancer-specific survival (CSS) with hazard ratio 2.6 (95%CI: 1.8-3.9, P < 0.001). The concordance index of a multivariate model with probability of N2 disease as a prognostic factor for survival was 0.68 for all patients and 0.75 for patients with less than 10 lymph nodes examined.

CONCLUSION

Utilizing estimated probabilities of N2 disease improves our ability to predict survival, in particular in patients with low LN count. These probabilities allow for a simple rule in patient counseling and clinical decision making.

Dukes C colorectal cancer: is the metastatic lymph node ratio important?

PURPOSE

Although the regional lymph node status is essential for staging of colorectal cancer, the importance of the total number of collected nodes remains controversial. Our aim was to examine the impact of the metastatic lymph node ratio (LNR) on the survival of patients with Dukes C colorectal cancer.

METHODS

All patients with Dukes C histology were selected from a prospectively collected database of all colorectal cancers resected between 1997 and 2007 at our institution. Demographic, histopathological and adjuvant treatment data were collected. The total number of positive lymph nodes was divided by the total number of lymph nodes examined to calculate the LNR. Patients were categorised into LNR groups 1 to 5 according to cut-off points: ≤0.1, 0.21, 0.36, 0.6 and ≥0.61. Survival from the date of operation was calculated using Kaplan-Meier estimates. Multivariate analysis was performed to identify those factors influencing survival.

RESULTS

Of 1,098 patients who underwent colorectal cancer resections, 41% were staged as Dukes C. Sixty-four percent of patients received chemotherapy. The median number of lymph nodes harvested and positive for tumour were 11 (range 1-52) and 4 (range 1-28), respectively. In patients who received chemotherapy, 5-year survival was 69.3% for LNR 1 and 23.6% for LNR 5. When no chemotherapy was given, the 5-year survival was 43.1% for LNR 1 and 8.7% for LNR 5.

CONCLUSIONS

Current evaluation of positive lymph nodes may not accurately stage Dukes C colorectal cancer. The assessment of the LNR is a useful prognostic method in this heterogenous group of patients.

Prognostic Significance of Lymph Node Ratio in Stage III Rectal Cancer

Purpose

Although nodal metastasis is the most powerful prognostic factor in rectal cancer, marked heterogeneity exists within stage III rectal cancer. Recent studies of rectal cancer have shown a prognostic superiority of the lymph node ratio (LNR) compared with N stage. The purpose of this study was to investigate the prognostic value of the LNR in the era of the 7th edition of the TNM classification.

Methods

We included 190 patients who underwent a curative resection for rectal cancer with nodal metastasis. The patients were divided into four groups on the basis of statistically calculated cut-off values as 0.21, 0.32, and 0.61.

Results

The LNR was an independent risk factor for overall survival (OS; P = 0.008) and for systemic recurrence-free survival (SRFS; P = 0.002). However, the LNR was not a predictive factor for local recurrence. When the N stage of the sixth TNM staging system was separately analyzed as a covariate, the LNR was also found to be a predictive factor for both OS and SRFS (P = 0.012 and P = 0.004, respectively). A LNR value of 0.21 offered the best cut off to separate patients into two prognostic groups.

Conclusion

The defined cut-off values of the LNR were an independent risk factor for OS and distant metastasis-free survival in patients with rectal cancer, irrespective of the sixth or the seventh version of the TNM classification, and the LNR should be considered as a prognostic variable in any future staging system.

Significance of metastatic lymph node ratio on stimulated thyroglobulin levels in papillary thyroid carcinoma after prophylactic unilateral central neck dissection

Background

Prognostic significance of metastatic central lymph node ratio (CLNR) in papillary thyroid carcinoma (PTC) remains unknown. Because postsurgical detectable stimulated thyroglobulin (DsTg) after radioiodine ablation may imply persistent or recurrent disease, we evaluated the association between CLNR and rate of DsTg in patients with PTC who underwent unilateral prophylactic central neck dissection.

Methods

To be eligible for analysis, the prophylactic central neck dissection specimen had to contain ≥3 central lymph nodes (CLNs) with ≥1 harboring metastasis. Of 129 specimens, 51 (39.5%) were eligible. CLNR was calculated as follows: (number of metastatic CLNs/number of CLNs retrieved) × 100. They were categorized into group 1 (CLNR <33.34%) (n = 14), group 2 (CLNR 33.34–66.67%) (n = 15), and group 3 (CLNR >66.67%) (n = 22). Postablation sTg level was measured 6 months after radioiodine ablation. A multivariate analysis was conducted to identify factors for postablation DsTg.

Results

Young age, palpable neck swelling, large tumor size, advanced tumor, node, metastasis system (TNM) stage, and large number of metastatic CLNs were significantly associated with high CLNR (P < 0.05). Compared to groups 1 and 2, group 3 had significantly higher DsTg rate (P = 0.018). Those who developed subsequent recurrence had significantly higher DsTg rate than those who did not (100% vs. 39.1%, P = 0.013). In the multivariate analysis for postablative DsTg, after adjusting for age, palpable neck swelling, tumor size, TNM stage, and number of metastatic CLNs, CLNR was the only independent factor (odds ratio 1.15, 95% confidence interval 1.01–1.31, P = 0.036).

Conclusions

A higher CLNR was associated with a higher rate of postablative DsTg; this may imply higher future recurrence rate.

Clinical impact of lymph node status in rectal cancer

Lymph node status at the time of diagnosis remains one of the principal indicators of prognosis in patients with rectal cancer. Involvement of loco-regional lymph nodes is relevant to surgical and clinical oncologists and continues to impact significantly upon local and systemic management strategies, in both neo-adjuvant and adjuvant settings. In this review, the clinical impact of lymph node status in the surgical management of rectal cancer is considered, with particular reference to the significance of lymphadenectomy and the potential implications for rectal tumours amenable to trans-anal excision. Current standards of care are reviewed and the extent to which the determination of lymph node status influences oncological decisions regarding neo-adjuvant and adjuvant therapies are discussed with areas of controversy highlighted.

Nomograms for predicting local recurrence, distant metastases, and overall survival for patients with locally advanced rectal cancer on the basis of European randomized clinical trials

PURPOSE

The purpose of this study was to develop accurate models and nomograms to predict local recurrence, distant metastases, and survival for patients with locally advanced rectal cancer treated with long-course chemoradiotherapy (CRT) followed by surgery and to allow for a selection of patients who may benefit most from postoperative adjuvant chemotherapy and close follow-up.

PATIENTS AND METHODS

All data (N = 2,795) from five major European clinical trials for rectal cancer were pooled and used to perform an extensive survival analysis and to develop multivariate nomograms based on Cox regression. Data from one trial was used as an external validation set. The variables used in the analysis were sex, age, clinical tumor stage stage, tumor location, radiotherapy dose, concurrent and adjuvant chemotherapy, surgery procedure, and pTNM stage. Model performance was evaluated by the concordance index (c-index). Risk group stratification was proposed for the nomograms.

RESULTS

The nomograms are able to predict events with a c-index for external validation of local recurrence (LR; 0.68), distant metastases (DM; 0.73), and overall survival (OS; 0.70). Pathologic staging is essential for accurate prediction of long-term outcome. Both preoperative CRT and adjuvant chemotherapy have an added value when predicting LR, DM, and OS rates. The stratification in risk groups allows significant distinction between Kaplan-Meier curves for outcome.

CONCLUSION

The easy-to-use nomograms can predict LR, DM, and OS over a 5-year period after surgery. They may be used as decision support tools in future trials by using the three defined risk groups to select patients for postoperative chemotherapy and close follow-up (http://www.predictcancer.org).