Prognostic value of total number of lymph nodes retrieved differs between left-sided colon cancer and right-sided colon cancer in stage III patients with colon cancer

Extended procedure has no oncological benefits over segmental resection in the treatment of non-metastatic splenic flexure colon cancer, a population-based cohort study and a single center's decade-long experience

To compare the oncological survival outcome between extended resections (ER) and segmental resection (SR) for non-metastatic splenic flexure tumors. A total of 10,063 splenic flexure colon cancers patients who underwent ER (n = 5546) or SR (n = 4517) from 2010 to 2018 were included from the Surveillance, Epidemiology, and End Results (SEER)-registered database. Additionally, we included 135 patients from our center who underwent ER (n = 54) or SR (n = 81) between 2011 and 2021. Survival rates were compared between groups. To reduce the inherent bias of retrospective studies, propensity score matching (PSM) analysis was performed. In the SEER database, patients in the ER group exhibited higher pT stage, pN stage, larger tumor size, and elevated rates of CEA level, perineural invasion, and tumor deposits compared to those in the SR group (each P < 0.05). The 5-year cancer-specific survival (CSS) rate was slightly lower in the ER group than in the SR group (79.2% vs. 81.6%, P = 0.002), while the 5-year overall survival (OS) rates were comparable between the two groups (66.2% vs. 66.9%, P = 0.513). After performing PSM, both the 5-year CSS and 5-year OS rates were comparable between the ER and SR groups (5-year CSS: 84.9% vs. 83.0%, P = 0.577; 5-year OS: 70.6% vs. 66.0%, P = 0.415). These findings were consistent in the subgroup analysis that included only patients with stage III disease or tumor size ≥ 7 cm. Furthermore, although the number of harvested lymph nodes was higher in the ER group compared to the SR group (14.4 vs. 12.7, P < 0.001), the number of invaded lymph nodes remained similar between the two groups (0.5 vs. 0.5, P = 0.90). Similarly, our center's data revealed comparable 3-year OS and 3-year disease-free survival (DFS) rates between the two groups. ER have no significant oncological benefits over SR in the treatment of non-metastatic splenic flexure colon cancer, even for locally advanced cases.

Evaluation of the prognostic performance of different cutoff values of lymph node ratio staging system for stage III colorectal cancer

This study attempted to compare the prognostic performance of lymph node ratio (LNR) staging system with different cutoff values relative to American Joint Committee on Cancer (AJCC) pN staging system in stage III colorectal cancer (CRC). Overall, 45,069 patients from the SEER dataset and 69 patients from the Second Affiliated Hospital of Nanjing Medical University (the External set) who underwent surgical resection of the primary tumor and were diagnosed with stage III CRC by postoperative pathology were included. Patients were divided into three subgroups based on the LNR cutoff used in previous studies, Kaplan-Meier curves were plotted, and log-rank test was used to compare the differences among groups in terms of cancer-specific survival (CSS). Cox regression model was applied for survival analysis. To evaluate the discriminatory power of different lymph node staging systems, Harrell's C statistic(C-index) and Akaike's Information Criterion (AIC) were applied. A set of optimal cutoff values (0.11; 0.36; 0.66) of LNR staging system with the most considerable discriminatory power to the prognosis in patients with stage III CRC (SEER set: C-index = 0.714; AIC = 58,942.46, External set: C-index = 0.809; AIC = 164.36) were obtained, and both were superior to the AJCC pN staging system (SEER set: C-index = 0.708; AIC = 59,071.20, External set: C-index = 0.788; AIC = 167.06). For evaluating the prognostic efficacy of patients with stage III colorectal cancer, the cutoff value (0.11; 0.36; 0.66) of LNR staging system had the best discrimination and prognostic ability, which was superior to LNR staging system under other cutoff values and AJCC pN staging system.

Expression and Prognosis of Differential Gene Troponin T1 Between Right and Left Colon Cancers

Colorectal cancer (CRC) is one of the most common digestive tract tumors in humans. At present, many scholars believe that the primary site of the tumor has a direct and profound impact on its curative effect. There are significant differences in the expression of many genes, tumor microenvironment, and prognosis between the left and right colon. However, there is a lack of detailed studies on whether the differentially expressed genes in the left and right colon significantly impact the prognosis of patients with CRC. Troponin T1 ( TNNT1 ) is an important gene that affects the prognosis difference between left and right colon cancer screening from "The Cancer Genome Atlas" database. By analyzing the differential gene expression data and clinical data of the left and right hemicolons in the database, the online prognostic database was used to screen the key molecules that significantly affect the tumor immune microenvironment and patient prognosis and to predict their functions and pathways. Quantitative reverse transcription-polymerase chain reaction was used to verify the expression difference of TNNT1 in CRC cell lines SW480 and HCT116, and normal human colorectal epithelial cell line FHC. The relationship between TNNT1 expression in 88 pairs of CRC samples and clinical information and pathologic parameters of patients with CRC was analyzed to judge the impact of TNNT1 expression on patient survival. Database analysis showed that TNNT1 was significantly overexpressed in CRC, and TNNT1 was one of the main differential genes between left colon cancer (LCC) and right colon cancer (RCC). The expression of TNNT1 was significantly increased in RCC, which could lead to poor prognosis of patients. Quantitative reverse transcription-polymerase chain reaction indicated that the expression of TNNT1 was significantly up-regulated in CRC cell lines SW480 and HCT116. Eighty-eight immunohistochemistry (IHC) of CRC tissues and adjacent tissues suggested that the expression of TNNT1 in CRC was significantly higher than that in normal adjacent tissues. By analyzing the clinical information and pathologic indicators matched with these clinical samples, we found that high TNNT1 expression in the primary tumor location (right colon) and high N stage (N2, N3) were unfavorable factors affecting the prognosis of patients with CRC. Multivariate Cox regression analysis suggested that high expression of TNNT1 may be an independent risk factor for the prognosis of patients with CRC. As one of the main differential genes between LCC and RCC, TNNT1 is representative to some extent. Its high expression may be one of the reasons why the prognosis of patients with RCC is worse than that of patients with LCC.

Extent of Lymph Node Harvest: A Retrospective Cohort Comparison of Intracorporeal Versus Extracorporeal Anastomosis in Right Hemicolectomy

Background: Minimally invasive surgery has been demonstrated to have clear advantages in colon cancer management, with a decrease in the morbidity and mortality associated with surgery. With the introduction of intracorporeal anastomosis (ICA), the entire mesenteric dissection and division is performed under vision laparoscopically and may lead to superior lymph node harvest. The aim of our study is to evaluate lymph node harvest in patients undergoing totally laparoscopic right hemicolectomy with ICA compared to laparoscopic-assisted right hemicolectomy with extracorporeal anastomosis (ECA). Methods: This is a single institution retrospective cohort study. Eligible patients underwent laparoscopic right hemicolectomy at our institution between 2012 and 2022. Patients were identified using a hospital database, and surgeon office databases. Patients included underwent laparoscopic right hemicolectomy for neoplastic lesions (colon cancer/unresectable polyps), or benign etiologies. We excluded patients who underwent laparotomy (intra-operative conversion), resection without anastomosis, resection for IBD, or lack of documented lymph node number. Data were compared using two-sided t-test evaluation with a 95% confidence interval. Results: A total of 679 patients were included, 493 ECA (72.6%) and 186 ICA (27.4%). Patient demographics (age, biologic sex, American Society of Anesthesiologists and body mass index) were not significantly different. Lymph node harvest was significantly higher in those with ICA (24 ± 14 versus 21 ± 1, P < .05). In subgroup analysis, this difference was maintained in patients with malignant processes (27 ± 14 versus 23 ± 10, P < .05). Conclusions: In our experience, ICA has higher lymph node harvest in comparison to ECA. This may improve outcomes and options for adjuvant therapies in malignant indications.

Correlation between lymph node size on pathology and metastatic disease in right-sided colon cancer: A retrospective review

BACKGROUND

Identification of positive lymph nodes in colon cancer can significantly impact treatment. Few studies have examined the role of lymph node size in staging and prognosis. This study evaluated the relationship between lymph node size and lymph node metastases in right-sided colon cancer.

METHODS

Retrospective chart review was performed for patients undergoing colectomy for right-sided colon cancer from 2015 to 2020 across a single multi-hospital health system. Patients under age 18 or who did not have invasive adenocarcinoma upon pathological examination were excluded. Primary endpoints assessed lymph node size and lymph node metastases. 572 patients were stratified by lymph node size; lymph nodes ≥5 mm (n = 308) were characterized as enlarged.

RESULTS

All surgical specimens examined had adequate number of lymph nodes for staging. 33.9% of all specimens examined contained lymph node metastases. Patients with enlarged lymph nodes were significantly more likely to have lymph node metastases than those with normal-sized lymph nodes (p < 0.001). Enlarged lymph nodes were associated with advanced nodal staging.

CONCLUSIONS

Patients with enlarged nodes were significantly more likely to have lymph node metastases than those with normal-sized lymph nodes. Further research to analyze these enlarged lymph nodes on radiologic imaging is warranted to determine the role of radiographic assessment of lymph node size during pre-operative staging.

Comparison of open, laparoscopic, and robotic left colectomy for radical treatment of colon cancer: a retrospective analysis in a consecutive series of 211 patients

Background

Robotic surgery has been widely used in the radical treatment of colonic cancer. However, it is unclear what advantages the robotic approach offers over other approaches in left colectomy. This study aims to explore the advantage of robotic surgery in left colectomy by comparing open, laparoscopic, and robotic surgery.

Methods

A retrospective analysis was performed on the clinical data of patients with radical left colectomy for colon cancer who were admitted to the Department of General Surgery, The First Affiliated Hospital of Nanchang University, from November 2012 to November 2017. Two hundred eleven patients included were divided into the open surgery group (OS, n=49), laparoscopic surgery group (LS, n=92), and robotic surgery group (RS, n=70) according to surgical techniques. The clinicopathologic data were collected for clinical outcome assessment. Finally, the clinical value of RS in radical left colectomy was further evaluated by propensity score matching (PSM) analysis.

Results

Three groups were similar in demographics and clinical characteristics. Compared with OS, LS and RS groups had better intraoperative and perioperative clinical outcomes. Moreover, the RS group exhibited the minimum operative times, length of stay (LOS), and evaluated blood loss. LS and RS also exhibited less perioperative and postoperative long-term complications. Three groups showed similar postoperative pathological outcomes. The overall survival and disease-free survival were also similar among the three groups (all P > 0.05). Cox regression analysis showed surgical approach was not a prognostic factor for overall survival (P = 0.671) and disease-free survival (P = 0.776). PSM analysis of RS and LS by clinical characteristics showed RS showed shorter operation time (P < 0.001) and LOS for patients without complications (P = 0.005). However, no significant differences were found in perioperative and long-term postoperative complications, pathological outcomes, overall survival, and disease-free survival.

Conclusions

Among three techniques for radical left colectomy, LS and RS had significant advantages over OS in short-term clinical outcomes, and no significant differences were found in overall, disease-free survival, local recurrence, and distant metastasis incidence. Moreover, RS shows better perioperative clinical outcomes but without compromising survival compared with LS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02796-8.

Construction and validation of nomograms based on the log odds of positive lymph nodes to predict the prognosis of lung neuroendocrine tumors

Background

This research aimed to investigate the predictive performance of log odds of positive lymph nodes (LODDS) for the long-term prognosis of patients with node-positive lung neuroendocrine tumors (LNETs).

Methods

We collected 506 eligible patients with resected N1/N2 classification LNETs from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. The study cohort was split into derivation cohort (n=300) and external validation cohort (n=206) based on different geographic regions. Nomograms were constructed based on the derivation cohort and validated using the external validation cohort to predict the 1-, 3-, and 5-year cancer-specific survival (CSS) and overall survival (OS) of patients with LNETs. The accuracy and clinical practicability of nomograms were tested by Harrell’s concordance index (C-index), integrated discrimination improvement (IDI), net reclassification improvement (NRI), calibration plots, and decision curve analyses.

Results

The Cox proportional-hazards model showed the high LODDS group (-0.79≤LODDS) had significantly higher mortality compared to those in the low LODDS group (LODDS<-0.79) for both CSS and OS. In addition, age at diagnosis, sex, histotype, type of surgery, radiotherapy, and chemotherapy were also chosen as predictors in Cox regression analyses using stepwise Akaike information criterion method and included in the nomograms. The values of C-index, NRI, and IDI proved that the established nomograms were better than the conventional eighth edition of the TNM staging system. The calibration plots for predictions of the 1-, 3-, and 5-year CSS/OS were in excellent agreement. Decision curve analyses showed that the nomograms had value in terms of clinical application.

Conclusions

We created visualized nomograms for CSS and OS of LNET patients, facilitating clinicians to bring individually tailored risk assessment and therapy.

Long-Time Trend of Colorectal Cancer Mortality Attributable to High Processed Meat Intake in China and a Bayesian Projection from 2020 to 2030: A Model-Based Study

Colorectal cancer is among the leading causes of cancer worldwide. Processed meat was known to be positively associated with a higher risk of gastrointestinal cancer. This study focused on the long-time trends of colorectal cancer mortality attributable to high processed meat intake in China from 1990 to 2019 and the projection for the next decade based on data obtained from the Global Burden of Disease 2019 study. We used an age-period-cohort model to fit the long-time trend. The joinpoint model was conducted to estimate the average and annual change of the attributable mortality. The Bayesian age-period-cohort model was used to project the crude attributable mortality from 2020 to 2030. An upward trend in colorectal cancer mortality attributable to high processed meat intake was observed for both sexes in China from 1990 to 2019, with an overall net drift of 4.009% for males and 2.491% for females per year. Projection analysis suggested that the burden of colorectal cancer incidence and mortality would still be high. Our findings suggested that colorectal cancer death attributable to high processed meat intake is still high in China, and elderly males were at higher risk. Gradually decreasing the intake of processed meat could be an effective way to reduce colorectal cancer mortality.

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Development and external validation of a novel nomogram for predicting cancer-specific survival in patients with ascending colon adenocarcinoma after surgery: a population-based study

Background

This study aimed to develop and validate a novel nomogram to predict the cancer-specific survival (CSS) of patients with ascending colon adenocarcinoma after surgery.

Methods

Patients with ascending colon adenocarcinoma were enrolled from the Surveillance, Epidemiology, and End Results (SEER) database from 1973 to 2015 and randomly divided into a training set (5930) and a validation set (2540). The cut-off values for age, tumour size and lymph node ratio (LNR) were calculated via X-tile software. In the training set, independent prognostic factors were identified using univariate and multivariate Cox analyses, and a nomogram incorporating these factors was subsequently built. Data from the validation set were used to assess the reliability and accuracy of the nomogram and then compared with the 8th edition of the American Joint Committee on Cancer (AJCC) tumour-node-metastasis (TNM) staging system. Furthermore, external validation was performed from a single institution in China.

Results

A total of 8470 patients were enrolled from the SEER database, 5930 patients were allocated to the training set, 2540 were allocated to the internal validation set and a separate set of 473 patients was allocated to the external validation set. The optimal cut-off values of age, tumour size and lymph node ratio were 73 and 85, 33 and 75 and 4.9 and 32.8, respectively. Univariate and multivariate Cox multivariate regression revealed that age, AJCC 8th edition T, N and M stage, carcinoembryonic antigen (CEA), tumour differentiation, chemotherapy, perineural invasion and LNR were independent risk factors for patient CSS. The nomogram showed good predictive ability, as indicated by discriminative ability and calibration, with C statistics of 0.835 (95% CI, 0.823–0.847) and 0.848 (95% CI, 0.830–0.866) in the training and validation sets and 0.732 (95% CI, 0.664–0.799) in the external validation set. The nomogram showed favourable discrimination and calibration abilities and performed better than the AJCC TNM staging system.

Conclusions

A novel validated nomogram could effectively predict patients with ascending colon adenocarcinoma after surgery, and this predictive power may guide clinicians in accurate prognostic judgement.

Lymph node status and its impact on the prognosis of left-sided and right-sided colon cancer: A SEER population-based study

Background

Some significant differences exist between the outcomes of left‐ and right‐sided colon cancer patients. The presence of nodal metastases is a critical prognostic factor, especially in the absence of distant metastasis. Our research studied the lymph nodes status of left‐ and right‐sided colon cancer patients to determine the influence of this factor on prognosis.

Methods

Our data were obtained from the Surveillance, Epidemiology and End Results (SEER) database. We used the chi‐square test to analyze the clinicopathological characteristics. The X‐tile program was adopted to acquire optimal cutoff points of lymph node index. Kaplan–Meier curves were used to analyze prognosis and multivariate Cox regression models were performed to identify the independent factors associated with survival. Nomograms were built to predict the overall survival of patients, Harrell's C‐index and calibration plots were used to validate the nomograms.

Results

The study included 189,941 patients with colon cancer without metastasis (left 69,885, right 120,056) between 2004 and 2015. There are more patients with adequate examined lymph nodes in right‐sided. Lymph node status in patients with right colon cancer has a more significant impact on the risk of death. LODDS (C‐index: 0.583; AIC: 6875.4) was used to assess lymph node status. The nomograms showed that lymph node status was the main factor to predict the outcome in right‐sided colon patients.

Conclusions

The influence of lymph node status on predicting prognosis is significantly different between patients with left and right colon cancer without metastasis. The tumor site needs to be considered when lymph node status is used to assess the outcome of patients.

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

High Tissue TLR5 Expression Predicts Better Outcomes in Colorectal Cancer Patients

BACKGROUND

Colorectal cancer (CRC), the third most common cancer globally, caused 881,000 cancer deaths in 2018. Toll-like receptors (TLRs), the primary sensors of pathogen-associated molecular patterns and damage-associated molecular patterns, activate innate and adaptive immune systems and participate in the development of an inflammatory tumor microenvironment. We aimed to explore the prognostic value of TLR3, TLR5, TLR7, and TLR9 tissue expressions in CRC patients.

METHODS

Using immunohistochemistry, we analyzed tissue microarray samples from 825 CRC patients who underwent surgery between 1982 and 2002 at the Department of Surgery, Helsinki University Hospital, Finland. After analyzing a pilot series of 205 tissue samples, we included only TLR5 and TLR7 in the remainder of the patient series. We evaluated the associations between TLR5 and TLR7 tissue expressions, clinicopathologic variables, and survival. Using the Kaplan-Meier method, we generated survival curves, determining significance using the log-rank test. Univariate and multivariate survival analyses relied on the Cox proportional hazards model.

RESULTS

The 5-year disease-specific survival was 55.9% among TLR5-negative (95% confidence interval [CI] 50.6-61.2%) and 61.9% (95% CI 56.6-67.2%; p = 0.011, log-rank test) among TLR5-positive patients. In the Cox multivariate survival analysis adjusted for age, sex, stage, location, and grade, positive TLR5 immunoexpression (hazard ratio [HR] 0.74; 95% CI 0.59-0.92; p = 0.007) served as an independent positive prognostic factor. TLR7 immunoexpression exhibited no prognostic value in the survival analysis across the entire cohort (HR 0.97; 95% CI 0.78-1.20; p = 0.754) nor in subgroup analyses.

CONCLUSIONS

We show for the first time that a high TLR5 tumor tissue expression associates with a better prognosis in CRC patients.

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

Background

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

Methods

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

Results

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

Conclusions

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

Supplementary Information

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

Association of day of the week with mortality after elective right hemicolectomy for colon cancer: Case analysis from the National Clinical Database

AIM

We aimed to investigate whether later weekdays are related to worse short-term outcomes after elective right hemicolectomy for colon cancer.

METHODS

We retrospectively analyzed adult patients who underwent elective right hemicolectomy for colon cancer between 2012 and 2017. Records lacking details about surgical mortality were excluded, and multiple imputation was performed for other missing data (variables). The primary endpoint was surgical mortality, defined as the sum of 30-day mortality and in-hospital deaths within 90 days postoperatively. Using 22 clinical variables, hierarchal logistic regression modeling with clustering of patients from the same institutes was performed.

RESULTS

Of the 112 658 patients undergoing elective right hemicolectomy for colon cancer, the 30-day mortality and surgical mortality were 0.6% and 1.1%, respectively. Surgery on Friday was less frequent, accounting for 17.1% of all cases. The occurrence of severe postoperative complications, anastomotic leakage, or unadjusted odds ratio for surgical mortality did not show significant differences between weekdays. A hierarchal logistic regression model identified 19 independent factors for surgical mortality. Adjusted odds ratios for surgical mortality were 1.01 (95% confidence interval: 0.83-1.22, P = .915), 0.86 (95% confidence interval: 0.71-1.05, P = .144), 0.86 (95% confidence interval: 0.71-1.05, P = .408), and 0.83 (95% confidence interval: 0.68-1.03, P = .176) for Tuesday, Wednesday, Thursday, and Friday, respectively, showing no significant differences.

CONCLUSION

This study did not identify an evident difference in surgical mortality between weekdays; a safe elective right hemicolectomy for colon cancer is being offered throughout the week in Japan.

Impact of D3 lymph node dissection on upstaging and short-term survival in clinical stage I right-sided colon cancer

BACKGROUND

D3 lymph node dissection is becoming the standard procedure for the treatment of advanced right colon cancer and has shown increasing evidence of its oncologic benefit. However, a clear indication for its application is lacking and data on this topic is unsatisfactory. Thus, the necessity for D3 lymph node dissection in clinical stage I right colon cancer remains controversial.

METHODS

We retrospectively analyzed data from clinical stage I right colon cancer patients who underwent radical surgery at three hospitals of Korea university medical center between January 2015 and June 2018. We compared surgical complications and short-term oncologic outcomes between D2 and D3 lymph node dissections in these patients.

RESULTS

Among 512 patients, 122 (23.8%) were clinical stage I. Of these, 88 and 34 patients received D2 and D3 lymph node dissection, respectively. There were no statistically significant differences in clinicopathologic variables and surgical outcomes between the two groups. Upstaging occurred in 16 patients (47.1%) in the D3 group and 23 patients (26.1%) in the D2 group. There were four recurrences in the D2 group but no recurrence in the D3 group. Log-rank tests showed no statistically significant difference in disease-free survival rates between the two groups (p = 0.210).

CONCLUSION

There was no significant difference in disease-free survival rates between D2 and D3 lymph node dissection in clinical stage I right colon cancer patients. However, recurrence occurred in the D2 group. Efforts to improve the accuracy of clinical staging are required and more studies with better quality are needed.

Prediction of Recurrence in Patients with Stage III Colon Cancer Using Conventional Clinicopathological Factors and Peripheral Blood Test Data: A New Analysis with Artificial Intelligence

BACKGROUND

Survival rate may be predicted by tumor-node-metastasis staging systems in colon cancer. In clinical practice, about 20 to 30 clinicopathological factors and blood test data have been used. Various predictive factors for recurrence have been advocated; however, the interactions are complex and remain to be established. We used artificial intelligence (AI) to examine predictive factors related to recurrence.

METHODS

The study group comprised 217 patients who underwent curative surgery for stage III colon cancer. Using a self-organizing map (SOM), an AI-based method, patients with only 23 clinicopathological factors, patients with 23 clinicopathological factors and 34 of preoperative blood test data (pre-data), and those with 23 clinicopathological factors and 31 of postoperative blood test data (post-data) were classified into several clusters with various rates of recurrence.

RESULTS

When only clinicopathological factors were used, the percentage of T4b disease, the percentage of N2 disease, and the number of metastatic lymph nodes were significantly higher in a cluster with a higher rate of recurrence. When clinicopathological factors and pre-data were used, three described pathological factors and the serum C-reactive protein (CRP) levels were significantly higher and the serum total protein (TP) levels, serum albumin levels, and the percentage of lymphocytes were significantly lower in a cluster with a higher rate of recurrence. When clinicopathological factors and post-data were used, three described pathological factors, serum CRP levels, and serum carcinoembryonic antigen levels were significantly higher and serum TP levels, serum albumin levels, and the percentage of lymphocytes were significantly lower in a cluster with a higher rate of recurrence.

CONCLUSIONS

This AI-based analysis extracted several risk factors for recurrence from more than 50 pathological and blood test factors before and after surgery separately. This analysis may predict the risk of recurrence of a new patient by confirming which clusters this patient belongs to.

Prognostic impact of tumour sidedness in patients with stage II colon cancer: a single-centre retrospective study

BACKGROUND

The search for high-risk factors in stage II colon cancer (CC) is ongoing and several high-risk factors for stage II CC have been identified; however, the effects of tumour sidedness on prognosis are not clear. This study aims to determine whether tumour sidedness could be identified as another high-risk factor for stage II CC.

METHODS

We retrospectively analysed 189 patients with stage II CC and compared clinicopathological findings and long-term outcomes between the patients with right colonic cancer (RCC) and with left colonic cancer (LCC). Prognostic factors for survival were determined using univariate and Cox proportional regression analyses.

RESULTS

A total of 72 patients were diagnosed with RCC and 117 patients were diagnosed with LCC. Patients with RCC were significantly older (P < 0.001), and the number of harvested lymph nodes was greater in the RCC group (RCC: 25 versus LCC: 19; P = 0.003). The overall survival (OS) was worse in the RCC group than the OS in the LCC group (5-year survival rate - RCC: 81.3% versus LCC: 90.4%; P = 0.025). Cox proportional regression analysis showed that tumour sidedness was an independent prognostic factor for both OS (hazard ratio (HR) 3.78, 95% confidence interval (CI) 1.61-8.85, P = 0.022) and DFS (HR 2.58, 95% CI 1.33-4.99, P = 0.005).

CONCLUSION

Patients with RCC have more negative prognostic factors and worse long-term outcomes than those with LCC in stage II CC. Tumour sidedness is a high-risk factor in stage II CC patients.

Extricating the Association Between the Prognostic Factors of Colorectal Cancer

PURPOSE

Colorectal cancer (CRC) is one of the recurring and lethal gastrointestinal tract disease rankings as the primary cause of worldwide morbidity and mortality. In general, the tumour node metastasis (TNM) and Dukes classification assist in diagnosis, prognosis and treatments of CRC along with haematological examinations and tumour demographic characterisations in patients.

METHODS

The present investigation is carried out on clinically acknowledged sixty-five CRC patients based on haematological findings and are sorted into stages using TNM and Dukes. The present study is to find the association between haematological findings, demographic characters, differentiation position, lymph node invasion and tumour node metastasis in CRC patients in accordance with their age.

RESULTS

We observed significant (p < 0.05) nexus between lymph node metastasis and tumour node metastasis on the basis of tumour's differentiation demographic positioning and age of the individuals.

CONCLUSION

Earlier location tracing and medicinal treatment or surgery lessen the chance of CRC morbidity and mortality along with prolonging survival rate via prognostic factors and disease position determination.

Current Trends in the Quality Assessment of Colorectal Cancer Practice and Treatment in South Korea during 2012-2017

Purpose

Colorectal cancer (CRC) is increasing in South Korea due to westernized eating habits and regular health check-ups. The Korean Health Insurance Review and Assessment Service (HIRA) has conducted a national quality assessment of the treatment of CRC. This study examined the quality assessment report of the Korean HIRA and analyzed the status of practice pattern and the epidemiology of CRC in South Korea.

Materials and Methods

The number of subjects was determined based on the number of surgical procedures in each institution during 2012–2017. The institution types were classified according to the number of beds and the composition of oncologic specialists. Twenty-one indicators for diagnosis, chemotherapy, radiotherapy, surgery, pathology, and mortality were analyzed and the inter-institutional variation for each indicator was calculated.

Results

Among 21 evaluation indices, indicators related to medical records, receipt of chemotherapy with a high coefficient of variation of ≥ 0.1% were improved over 6 years until the survey in 2017. In the analysis of indices affecting surgical mortality, the regional lymph node resection and examination rate (p=0.022) showed a negative correlation with surgical mortality. Hospitalization stay (p < 0.001) and hospitalization cost (p=0.002) were positively correlated with surgical mortality.

Conclusion

This study showed that the treatment quality and examination status for CRC in South Korea were appropriate for improving relevant medical records, receipt of chemotherapy, maintaining the quality of treatment, and mortality. These analyses could be the basis for developing an improved quality assessment program worldwide.

Obstructing Left-Sided Colonic Cancer: Is Endoscopic Stenting a Bridge to Surgery or a Bridge to Nowhere?

For the 8-29% colorectal cancers that initially manifest with obstruction, emergency surgery (ES) was traditionally considered the only available therapy, despite high morbidity and mortality rates and the need for colostomy creation. More recently, malignant obstruction of the left colon can be temporized by endoscopic placement of a self-expanding metallic stent (SEMS), used as bridge to surgery (BTS), facilitating a laparoscopic approach and increasing the likelihood that a primary anastomosis instead of stoma would be used. Despite these attractive outcomes, the superiority of the BTS approach is not clearly established. Few authors have stressed the potential cancer risk associated with perforations that may occur during endoscopic stent placement, facilitating neoplastic spread and negatively impacting prognosis. For this reason, the current literature focuses on long-term oncologic outcomes such as disease-free survival, overall survival and recurrence rate that do seem not to differ between the ES and BTS approaches. This lack of consensus has spawned differing and sometimes discordant guidelines worldwide. In conclusion, 20 years after the first description of a colonic stent as BTS, the debate is still open, but the growing number of articles about the use of SEMS as a BTS signifies a great interest in the topic. We hope that these data will finally converge on a single set of recommendations supporting a management strategy with well-demonstrated superiority.

Prognostic value of log odds of positive lymph nodes in node-positive lung squamous cell carcinoma patients after surgery: a SEER population-based study

Background

Log odds of positive lymph nodes (LODDS) is a novel and promising ratio-based lymph node (LN) staging system in many malignancies. This study aimed to evaluate the prognostic value of LODDS, and comprehensively compare the prognostic predictive performance of LODDS with the American Joint Committee on Cancer (AJCC) N classification, number of positive lymph node (NPLN), and lymph node ratio (LNR) among node-positive lung squamous cell carcinoma (SCC) patients after surgery.

Methods

We identified 2,561 patients with N1/N2 stage SCC diagnosed between 2004 and 2014 from the Surveillance, Epidemiology, and End Results (SEER) database. X-tile analysis was used to calculate the optimal cut-off value for each staging system. Univariable and Multivariable Cox regression analyses were used to assess the association of cancer-specific survival (CSS), and overall survival (OS) with N, NPLN, LNR, and LODDS, separately, and integrally. Moreover, linear trend χ² score, likelihood ratio (LR) test, Akaike information criterion (AIC), and Harrell concordance index (C-index) were adopted as criteria for assessing the predictive ability of each model.

Results

The optimal cut-off values for NPLN, LNR, and LODDS were 3, 0.28, and −0.37, respectively. N, NPLN, LNR, and LODDS were identified as independent prognostic predictors for CSS and OS in patients with SCC when each of them was incorporated into multivariable Cox model separately. Additionally, LODDS had the higher linear trend χ² score, higher LR χ² test score, lower AIC, and higher C-index compared to the other three systems. Moreover, a combination of N, NPLN, and LODDS was superior to any staging system alone for predicting prognosis.

Conclusions

LODDS showed better predictive performance than N, NPLN, and LNR among patients with node-positive SCC after surgery. A combination of LODDS and the current AJCC TNM classification has the potential for becoming a better staging method to more precisely predicting prognosis.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

A reappraisal of lymph node dissection in colorectal cancer during primary surgical resection

Purpose

Controversy exists regarding the extent to which lymph node dissection (LND) should be performed for operable colorectal cancers (CRCs) during primary surgical resection. We reappraised the role of LND in CRCs.

Methods

Seventy-three CRC patients (mean age, 65.3 years; 43 males) undergoing primary surgical resection at Taipei Hospital, Ministry of Health and Welfare, Taiwan, within a 3-year period were retrospectively analyzed. Their pathological T/N/M statuses and cancer stages were defined according to the American Joint Committee on Cancer (AJCC) 8th edition staging system. The numbers of total dissected lymph nodes (TDLNs), positive dissected lymph nodes (PDLNs), and negative dissected lymph nodes (NDLNs) for each CRC patient were recorded in detail (TDLNs = PDLNs + NDLNs). Possible prognostic variables were evaluated.

Results

An advanced N status (N1/N2 vs. N0; HR, 5.749/17.677 vs. 1.000; p = 0.056/0.009) and M1 status (M1 vs. M0; HR, 7.517 vs. 1.000; p = 0.010) were independent variables for a poor prognosis. For all 73 CRC patients (p = 0.030), as well as T2 CRC patients (p = 0.061), those with > 15 TDLNs tended to have more PDLNs than those with ≤ 15 TDLNs. For 42 N(+) CRC patients (p = 0.007), as well as N2 CRC patients (p = 0.011), those with > 21 TDLNs tended to have more PDLNs than those with ≤ 21 TDLNs.

Conclusion

For CRC patients undergoing primary surgical resection, the number of TDLNs influences the accuracy of nodal staging. A minimum of 15 TDLNs is necessary for positive lymph nodes to be identified in CRC patients, and 21 TDLNs is sufficient for the severity of the N(+) status to be distinguished in N(+) CRC patients.

Accuracy of nodal staging is influenced by sidedness in colon cancer

Background

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

Methods

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

Results

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

Conclusions

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