Comparison of oncological outcomes of right-sided colon cancer versus left-sided colon cancer after curative resection: Which side is better outcome?

Investigating the role of county-level colorectal cancer screening rates on stage at diagnosis of colorectal cancer in rural Georgia

BACKGROUND

To examine the impact of county-level colorectal cancer (CRC) screening rates on stage at diagnosis of CRC and identify factors associated with stage at diagnosis across different levels of screening rates in rural Georgia.

METHODS

We performed a retrospective analysis utilizing data from 2004 to 2010 Surveillance, Epidemiology, and End Results Program. The 2013 United States Department of Agriculture rural-urban continuum codes were used to identify rural Georgia counties. The 2004-2010 National Cancer Institute small area estimates for screening behaviors were applied to link county-level CRC screening rates. Descriptive statistics and multinominal logistic regressions were performed.

RESULTS

Among 4,839 CRC patients, most patients diagnosed with localized CRC lived in low screening areas; however, many diagnosed with regionalized and distant CRC lived in high screening areas (p-value = 0.009). In multivariable analysis, rural patients living in high screening areas were 1.2-fold more likely to be diagnosed at a regionalized and distant stage of CRC (both p-value < 0.05). When examining the factors associated with stage at presentation, Black patients who lived in low screening areas were 36% more likely to be diagnosed with distant diseases compared to White patients (95% CI, 1.08-1.71). Among those living in high screening areas, patients with right-sided CRC were 38% more likely to have regionalized disease (95% CI, 1.09-1.74).

CONCLUSION

Patients living in high screening areas were more likely to have a later stage of CRC in rural Georgia.

IMPACT

Allocating CRC screening/treatment resources and improving CRC risk awareness should be prioritized for rural patients in Georgia.

Prognostic value of primary tumor location in colorectal cancer: an updated meta-analysis

The clinical, histological, and molecular differences between right-sided colon cancer (RCC) and left-sided colon cancer (RCC) have received considerable attention. Over the past decade, many articles have been published concerning the association between primary tumor location (PTL) of colorectal cancer and survival outcomes. Therefore, there is a growing need for an updated meta-analysis integrating the outcomes of recent studies to determine the prognostic role of right vs left-sidedness of PTL in patients with colorectal cancer. We conducted a comprehensive database review using PubMed, SCOPUS, and Cochrane library databases from February 2016 to March 2023 for prospective or retrospective studies reporting data on overall survival (OS) and cancer-specific survival (CSS) of RCC compared with LCC. A total of 60 cohort studies comprising 1,494,445 patients were included in the meta-analysis. We demonstrated that RCC is associated with a significantly increased risk of death compared with LCC by 25% (hazard ratio (HR), 1.25; 95% confidence interval (CI), 1.19-1.31; I2 = 78.4%; Z = 43.68). Results showed that patients with RCC have a worse OS compared with LCC only in advanced stages (Stage III: HR, 1.275; 95% CI 1.16-1.4; P = 0.0002; I2 = 85.8%; Stage IV: HR, 1.34; 95% CI 1.25-1.44; P < 0.0001; I2 = 69.2%) but not in primary stages (Stage I/II: HR, 1.275; 95% CI 1.16-1.4; P = 0.0002; I2 = 85.8%). Moreover, a meta-analysis of 13 studies including 812,644 patients revealed that there is no significant difference in CSS between RCC and LCC (HR, 1.121; 95% CI 0.97-1.3; P = 0.112). Findings from the present meta-analysis highlight the importance of PTL in clinical decision-making for patients with CRC, especially in advanced stages. We provide further evidence supporting the hypothesis that RCC and LCC are distinct disease entities that should be managed differently.

Prognostic Potential of Nectin Expressions in Colorectal Cancer: An Exploratory Study

Colorectal cancer (CRC) is a pressing global health challenge, with an estimated 1.9 million new cases in 2020. Ranking as the third most diagnosed cancer globally, CRC accounts for nearly 930,000 cancer-related deaths annually. Nectins, immunoglobulin-like adhesion molecules, are pivotal in intercellular adhesion formation and cellular function regulation. Altered nectin expression patterns have been identified in various cancers. However, the intricacies of their role in cancer development and progression remain underexplored. This study aimed to evaluate the expression of specific nectins in CRC tumors, explore their association with clinicopathological factors, and ascertain their potential as prognostic indicators for CRC patients post-resection. We retrospectively analyzed the medical records of 92 CRC patients who underwent surgical treatment between 2013 and 2014. Tumor specimens were re-evaluated to determine nectin expression using immunohistochemistry. The study identified heterogeneous expressions of nectin-2, -3, and -4 in 58%, 62.6%, and 87.9% of specimens, respectively. Elevated nectin-4 expression correlated with worse 5-year and overall survival rates, presenting a negative prognostic value (HR = 4, 95% CI: 2.4-6.8, p < 0.001). Conversely, reduced nectin-3 expression was linked to poorer CRC prognosis (HR = 0.54; 95% CI: 0.31-0.96; p = 0.036). Nectin-4 expression positively correlated with elevated carcinoembryonic antigen (CEA) levels and advanced disease stages. In contrast, nectin-3 expression negatively correlated with CEA levels, tumor size, presence of distant metastases, and disease stage. Notably, tumors in the right colon were statistically more likely to express nectin-2 compared to those in the left. This study underscores the potential prognostic significance of nectins in CRC. The high prevalence of nectin-4-expressing cells offers promising avenues for further evaluation in targeted therapeutic interventions with already available agents such as PADCEV.

Development and validation of prognostic nomograms for early-onset colon cancer in different tumor locations: a population-based study

OBJECTIVE

The prevalence of early-onset colon cancer (EOCC) among individuals below the age of 50 has shown a marked upward trend in recent years. The embryology, clinical symptoms, incidence, molecular pathways, and oncologic outcomes differ between right-sided and left-sided colon cancers. However, the differences have not been fully researched in EOCC. Our study aims to develop and validate prognostic nomograms predicting overall survival (OS) and cancer-specific survival (CSS) for EOCC in different tumor locations based on the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Using the SEER database, a total of 5,588 patients with EOCC were extracted and divided into development and validation cohorts in a random allocation ratio of 7:3 across three groups. Univariate and multivariate Cox regression analyses were performed to identify independent prognostic factors influencing OS and CSS outcomes. These factors were then utilized to construct nomogram models. The prognostic capabilities of the three models were assessed through various evaluation metrics, including the concordance index (C-index), receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and validation cohorts respectively. Additionally, survival curves of the low- and high-risk groups were calculated using the Kaplan-Meier method together with the log-rank test.

RESULTS

Significant differences in clinical features were observed between right-sided and left-sided EOCCs, particularly in terms of OS (52 months vs 54 months) as demonstrated by Kaplan-Meier curves. Transverse-sided EOCCs exhibited clinical characteristics similar to right-sided EOCCs, suggesting a potential shared tumor microenvironment and therapeutic considerations. Advanced stage, liver metastasis, poor grade, elevated pretreatment carcinoembryonic antigen (CEA) level, chemotherapy, and perineural invasion were identified as independent prognostic factors across all three tumor locations and were incorporated into the nomogram model. Nomograms were constructed to predict the probability of 3- and 5-year OS and CSS. The C-index and calibration plots showed that the established nomograms had good consistency between actual clinical observations and predicted outcomes. ROC curves with calculated area under the curve (AUC) values exceeded 0.8 for all three groups in both the development and validation cohorts, indicating robust predictive performance for OS and CSS. Furthermore, decision curve analysis (DCA) plots revealed a threshold probability range of 0.1 to 0.9, within which the nomogram model exhibited maximum benefit. Kaplan-Meier curves exhibited significant differences between the low- and high-risk groups in EOCC for all three tumor locations in OS and CSS, further validating the prognostic value of the nomogram models.

CONCLUSIONS

We successfully developed three precise nomogram models for EOCCs in different tumor locations, providing valuable support for clinicians in guiding clinical treatments and facilitating further prospective follow-up studies.

A Retrospective Study of the Prognostic Patterns in Colorectal Cancer Patients

Introduction  Colorectal cancer (CRC) management has advanced globally, leading to a steady decline in mortality rates. However, recent studies have shown that the prognosis of CRC varies based on the anatomical site of the primary tumor, histopathological grading, and type of mutation. With an increase in the incidence of CRC globally and in Bahrain, there is a need for a recent descriptive study to improve overall management. This study aims to investigate the anatomical, histopathological, and molecular prognostic factors in CRC patients presenting to the Salmaniya Medical Complex (SMC). Methods  The study was conducted retrospectively using ISEHA electronic database over two years (January 2019 to December 2020). A total of 101 patients with primary CRC registered in the General Surgery Department were included in this study. The sample size was further stratified and analyzed using descriptive statistics based on the available data of measured outcomes. Results  Anatomical data showed that 65% of CRC patients had a tumor on the left side of the colon, 27.7% on the right side, and 7% in the transverse colon. Overall, 16.8% of all patients had rectal involvement. Histopathological data showed that 86% of the patients had a low-grade CRC adenocarcinoma. The most diagnosed tumor stage was pT3N0M0 (22.8%). In addition, there were ten metastatic cases (10 to the liver, of which three had concomitant lung involvement and two had concurrent brain metastases). The average tumor diameter was 46.2 mm, where 63% ranged between 30 mm to 69 mm. Most mutations involved the TP53 (27.7%) and the KRAS (29%) genes.  Conclusion  The study found that majority of CRC patients at SMC in Bahrain had relatively good overall anatomical, tumor staging and grading prognostic factors but somewhat poorer molecular prognostics.

Survival rate of colorectal cancer in China: A systematic review and meta-analysis

Background

This study aims to comprehensively summarize the colorectal survival rate in China. Method: In PubMed and Web of Science, keywords such as "colorectal cancer", "survival" and "China" were used to search literatures in the past 10 years. Random effect models were selected to summarize 1-year, 3-year, and 5-year survival rates, and meta-regression and subgroup analyses were performed on the included studies.

Results

A total of 16 retrospective and prospective studies providing survival rates for colorectal cancer in China were included. The 1-year, 3-year, and 5-year survival rates of colorectal cancer in China were 0.79, 0.72 and 0.62, respectively. In the included studies, the 5-year survival rates of stage I (5474 cases), stage II (9215 cases), stage III (8048 cases), and stage IV (4199 cases) colorectal cancer patients were 0.85, 0.81, 0.57 and 0.30, respectively. Among them, the 5-year survival rates of colorectal cancer were 0.82, 0.76, 0.71, 0.67, 0.66, 0.65 and 0.63 in Tianjin, Beijing, Guangdong, Shandong, Liaoning, Zhejiang and Shanghai, respectively.

Conclusion

The 5-year survival rate in China is close to that of most European countries, but still lower than Japan and South Korea, and the gap is gradually narrowing. Region, stage, differentiation, pathological type, and surgical approach can affect 5-year survival in colorectal cancer.

Systematic review registration

https://www.crd.york.ac.uk/prospero/ identifier, CRD42022357789.

KRAS Mutational Profiles among Colorectal Cancer Patients in the East Coast of Peninsular Malaysia

BACKGROUND

KRAS is a key driver gene in colorectal carcinogenesis. Despite this, there are still limited data on the mutational status of KRAS amongst colorectal cancer (CRC) patients in Malaysia. In the present study, we aimed to analyze the KRAS mutational profiles on codons 12 and 13 amongst CRC patients in Hospital Universiti Sains Malaysia, Kelantan, located on the East Coast of Peninsular Malaysia.

METHODS

DNA were extracted from formalin-fixed, paraffin-embedded tissues obtained from 33 CRC patients diagnosed between 2018 and 2019. Amplifications of codons 12 and 13 of KRAS were conducted using conventional polymerase chain reaction (PCR) followed by Sanger sequencing.

RESULTS

Mutations were identified in 36.4% (12/33) of patients, with G12D (50%) being the most frequent single-point mutation observed, followed by G12V (25%), G13D (16.7%), and G12S (8.3%). No correlation was found between mutant KRAS and location of the tumor, staging, and initial carcinoembryonic antigen (CEA) level.

CONCLUSION

Current analyses revealed that a significant proportion of CRC patients in the East Coast of Peninsular Malaysia have KRAS mutations, where this frequency is higher compared to those in the West Coast. The findings of this study would serve as a precursor for further research that explores KRAS mutational status and the profiling of other candidate genes among Malaysian CRC patients.

Long-term Oncological Results After Laparoscopic Sigmoidectomy for Adenocarcinoma

Purpose: Sigmoidectomy is performed in most cases for benign pathologies and mainly in cases of diverticulitis. Few studies in the literature report oncological results after sigmoidectomy for adenocarcinoma. The aim of this study was to report the long-term oncological outcomes after elective laparoscopic sigmoidectomy (LS) for adenocarcinoma. Methods: This study is a retrospective analysis of prospectively collected data. From January 2003 to February 2021, 173 patients underwent elective LS for adenocarcinoma. Twenty-four patients with a diagnosis of preoperative distant metastases were excluded (13.9%). Results: Seven postoperative complications were observed (7.1%). Of these, 2 (2%) anastomotic leakages were treated surgically by the Hartmann procedure (Clavien-Dindo grade III-b). The mean number of harvested lymph nodes with the specimen was 14.2 ± 7.1. At a median follow-up of 115 months (interquartile range 133.8), 2 (2%) and 9 patients (9.2%) had developed recurrence and metastases, respectively. During follow-up, 6 patients (6.1%) with metastases died due to disease progression and 6 other patients (6.1%) died due to causes other than cancer related. At the 5- and 10-year follow-ups, the overall survival rates were 90.5% ± 3.4% and 83.8% ± 4.5%, respectively, while the disease-free survival rates were 87.1% ± 4.1% and 83.5% ± 4.7%, respectively. Conclusion: LS is a safe and feasible technique both in terms of the number of harvested lymph nodes and oncological results. The possibility of sparing the colon without mobilizing the splenic flexure and dividing the left colic artery could reduce intra- and postoperative complications. Further studies with larger samples of patients are required to confirm these data.

A Transcriptome and Methylome Study Comparing Tissues of Early and Late Onset Colorectal Carcinoma

There is an increase in the incidence of early onset colorectal carcinoma (EOCRC). To better understand if there is any difference in molecular pathogenesis of EOCRC and late onset colorectal carcinoma (LOCRC), we compared the clinical, histological, transcriptome, and methylome profile of paired CRC and healthy colonic tissue from 67 EOCRC and 98 LOCRC patients. The frequency of stage 3 CRC, lymph node involvement, lymphovascular invasion, and perineural invasion was higher in the EOCRC group. Many of the cancer related pathways were differentially expressed in CRC tissue in both EOCRC and LOCRC patients. However, the magnitude of differential expression for some groups of genes, such as DNA damage repair genes and replication stress genes, were significantly less pronounced in the EOCRC group, suggesting less efficient DNA damage repair to be associated with EOCRC. A more marked methylation of "growth factor receptor" genes in LOCRC correlated with a more pronounced down-regulation of those genes in that group. From a therapeutic point of view, more over-expression of fatty acid synthase (FASN) among the LOCRC patients may suggest a better response of FASN targeted therapy in that group. The age of onset of CRC did not appear to modify the response of cis-platin or certain immune checkpoint inhibitors. We found some differences in the molecular pathogenesis in EOCRC and LOCRC that may have some biological and therapeutic significance.

Extramural venous invasion and depth of extramural invasion on preoperative CT as prognostic imaging biomarkers in patients with locally advanced ascending colon cancer

PURPOSE

This study evaluates the prognostic significance of EMVI and DEMI on preoperative CT in patients with ascending colon cancer.

METHODS

This retrospective study included consecutive patients with T3 ascending colon cancer from January 2012 to December 2016 in a tertiary center. Two radiologists independently reviewed EMVI, DEMI, and nodal status on preoperative CT. We assessed the association of age, sex, mucinous adenocarcinoma, EMVI, and DEMI with metastasis on preoperative CT using univariable and multivariable analysis. We also compared disease-free survival (DFS) with and without variables (age, sex, mucinous adenocarcinoma, EMVI, DEMI and adjuvant chemotherapy) using Cox's proportional hazards models. We assessed interobserver agreements on imaging features using the Cohen's weighted kappa.

RESULTS

Of 237 patients [107 men; mean (standard deviation) age, 66 (13) years], 24 had metastases on preoperative CT. Positive EMVI was associated with metastasis (odds ratio 16.9; P < 0.001) on multivariable analysis. Of 194 patients [83 men; 65 (13) years] included for DFS analysis, recurrence was observed in 31 (16%) with median follow-up of 53 months. Positive EMVI [hazard ratio (HR) 4.8; P < 0.001] and DEMI > 5 mm (HR 5.5; P < 0.001) were associated with worse DFS. Interobserver agreements were good (kappa = 0.64-0.67).

CONCLUSION

Positive EMVI and DEMI > 5 mm on preoperative CT were associated with a worse T3 ascending colon cancer prognosis. Thus, these CT findings could be used as imaging biomarkers for T3 ascending colon cancer risk stratification.

Left-sided colorectal cancer distinct in indigenous African patients compared to other ethnic groups in South Africa

Introduction

A large proportion of indigenous African (IA) colorectal cancer (CRC) patients in South Africa are young (< 50 years), with no unique histopathological or molecular characteristics. Anatomical site as well as microsatellite instability (MSI) status have shown to be associated with different clinicopathological and molecular features. This study aimed to ascertain key histopathological features in microsatellite stable (MSS) and low-frequency MSI (MSI-L) patients, to provide insight into the mechanism of the disease.

Methods

A retrospective cohort (2011–2015) of MSS/MSI-L CRC patient samples diagnosed at Charlotte Maxeke Johannesburg Academic Hospital was analyzed. Samples were categorized by site [right colon cancer (RCC) versus left (LCC)], ethnicity [IA versus other ethnic groups (OEG)] and MSI status (MSI-L vs MSS). T-test, Fischer’s exact and Chi-square tests were conducted.

Results

IA patients with LCC demonstrated an increased prevalence in males, sigmoid colon, signet-ring-cell morphology, MSI-L with BAT25/26 marker instability and advanced disease association.

Conclusion

This study revealed distinct histopathological features for LCC, and suggests BAT25 and BAT26 as negative prognostic markers in African CRC patients. Larger confirmatory studies are recommended.

Practical Implications of KRAS Mutation Status and Sidedness of Primary Tumour in Patients with Colorectal Cancer and Synchronous Liver Metastases: A Subset Analysis of the CoSMIC Study

Patients with colorectal cancer presenting with synchronous liver metastases have less favourable outcomes than those with primary-only disease. There is evidence of different genetic mutational signatures according to the sidedness of the primary tumour. KRAS mutations are key driver mutations in colorectal cancer progression. This post hoc analysis of the previously reported CoSMIC inception cohort explores the association between primary tumour sidedness and KRAS mutational status on the outcome of patients with colorectal cancer and synchronous liver metastases. Patients diagnosed with synchronous disease were recruited between April 2014 and March 2017 and, after exclusions, 83 patients undergoing colorectal primary KRAS mutation testing constituted the final study population. Data were collected prospectively on demographic profiles, treatment, and outcomes. Twenty-one patients (25%) had right-sided tumours and 62 (75%) had left-sided tumours, with 46 (55%) and 37 (45%) exhibiting wildtype and mutated KRAS, respectively. There was no difference in distribution of liver metastases by KRAS status (unilobar vs. bi-lobar; p = 0.58; Fisher’s Exact test) and no difference in 5-year survival according to KRAS mutation status (Log-rank test, p = 0.82) or tumour sidedness (p = 0.16). In summary, in this cohort of patients with colorectal cancer and synchronous liver metastases, neither KRAS mutation status nor tumour sidedness influenced survival.

American Indian/Alaska Native and black colon cancer patients have poorer cause-specific survival based on disease stage and anatomic site of diagnosis

OBJECTIVES

Studies of race-specific colon cancer (CC) survival differences between right- vs. left-sided CC typically focus on Black and White persons and often consider all CC stages as one group. To more completely examine potential racial and ethnic disparities in side- and stage-specific survival, we evaluated 5-year CC cause-specific survival probabilities for five racial/ethnic groups by anatomic site (right or left colon) and stage (local, regional, distant).

METHODS

We obtained cause-specific survival probability estimates from National Cancer Institute's population-based Surveillance, Epidemiology, and End Results (SEER) for CC patients grouped by five racial/ethnic groups (Non-Hispanic American Indian/Alaska Native [AIAN], Non-Hispanic Asian/Pacific Islander [API], Hispanic, Non-Hispanic Black [NHB], and Non-Hispanic White [NHW]), anatomic site, stage, and other patient and SEER registry characteristics. We used meta-regression approaches to identify factors that explained differences in cause-specific survival.

RESULTS

Diagnoses of distant-stage CC were more common among NHB and AIAN persons (>22 %) than among NHW and API persons (< 20 %). Large disparities in anatomic site-specific survival were not apparent. Those with right-sided distant-stage CC had a one-year cause-specific survival probability that was 16.4 % points lower (99 % CI: 12.2-20.6) than those with left-sided distant-stage CC; this difference decreased over follow-up. Cause-specific survival probabilities were highest for API, and lowest for NHB, persons, though these differences varied substantially by stage at diagnosis. AIAN persons with localized-stage CC, and NHB persons with regional- and distant-stage CC, had significantly lower survival probabilities across follow-up.

CONCLUSIONS

There are differences in CC presentation according to anatomic site and disease stage among patients of distinct racial and ethnic backgrounds. This, coupled with the reality that there are persistent survival disparities, with NHB and AIAN persons experiencing worse prognosis, suggests that there are social or structural determinants of these disparities. Further research is needed to confirm whether these CC cause-specific survival disparities are due to differences in risk factors, screening patterns, cancer treatment, or surveillance, in order to overcome the existing differences in outcome.

Colon cancer CT staging according to mismatch repair status: Comparison and suggestion of imaging features for high-risk colon cancer

BACKGROUND

Neoadjuvant treatment with either chemotherapy or immunotherapy is gaining momentum in colon cancers (CC). To reduce over-treatment, increasing staging accuracy using computed tomography (CT) is of high importance.

PURPOSE

To assess and compare CT imaging features of CC between mismatch repair-proficient (pMMR) and MMR-deficient (dMMR) tumours and identify CT features that can distinguish high-risk (pT3-4, N+) CC according to MMR status.

METHODS

Primary staging CTs of 266 patients who underwent primary surgical resection of a colon tumour were retrospectively and independently evaluated by two radiologists. Logistic regression analysis was performed to identify significant associations between imaging features and positive lymph node status. Receiver operating characteristic (ROC) curves of significantly associated features were assessed and validated in an external cohort of 104 patients.

RESULTS

Among pT3 tumours only, dMMR CC were significantly larger than pMMR CC in both length and thickness (length 59.39 ± 26.28 mm versus 48.70 ± 23.72, respectively, p = 0.031; thickness 20.54 mm ± 11.17 versus 16.34 ± 8.73, respectively, p = 0.027). For pMMR tumours, nodal internal heterogeneity on CT was significantly associated with a positive lymph node status (odds ratio (OR) = 2.66, p = 0.027), while for dMMR tumours, the largest short diameter of the nodes was associated with lymph node status (OR = 2.01, p = 0.049). The best cut-off value of the largest short diameter of involved nodes was 10.4 mm for dMMR and 7.95 mm for pMMR. In the external validation cohort, AUCs for predicting involved nodes based on the largest short diameter was 0.764 for dMMR tumours using 10 mm size cut-off and 0.624 for pMMR tumours using 7 mm cut-off.

CONCLUSION

These data show that CT imaging features of primary CC differ between dMMR and pMMR tumours, suggesting that the assessment of CT-based CC staging should take MMR status into consideration, especially for lymph node status, and thus may help in selecting patients for neoadjuvant treatment.

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.

Outcomes of right-sided and left-sided colon cancer after curative resection

The right and left side of the colon derived from the midgut and hindgut, respectively. Previous studies have reported different characteristics of right-sided colon cancer (RCC) and left-sided colon cancer (LCC), but oncological outcomes remain unclear. This study compared the outcomes of RCC and LCC. This retrospective study included 1017 patients who received curative colectomy for stage I-III colon cancer at a single institute between August 2008 and December 2019. Overall survival (OS) and time to recurrence (TTR) were analyzed as outcome measurements. No significant difference in the OS or TTR of patients with RCC and LCC were observed. In subgroup analysis, RCC was associated with shorter TTR than LCC in stage II colon cancer (HR 2.36, 95% confidence interval 1.24–4.48, p < 0.01). Multivariate analysis demonstrated that right sidedness, R1 resection, low body mass index (BMI) and adjuvant chemotherapy were independent factors for poor prognosis for stage II colon cancer. Low BMI, perineural invasion, higher T stage and N2 stage were independent factors for poor prognosis for stage III colon cancer. The results were confirmed by multivariate analysis after propensity score matching. Our study revealed that RCC was an independent risk factor for recurrence in stage II colon cancer.

Evaluating the value of tumor length times width in colorectal adenocarcinoma with different tumor locations

The T classification, which reflects the vertical growth pattern of the tumor, is one of the most important prognostic factors in colorectal cancer. We aimed to investigate the prognostic value of tumor length and width in patients with colorectal cancer (CRC). A total of 259 patients with stage I-III CRC who underwent curative resection were reevaluated according to tumor location. One-way ANOVA analysis was conducted to investigate the relationship between the tumor length times width (TLTW) and clinical parameters. Univariate and multivariate analyses were conducted to analyze the potential prognostic factors affecting overall survival (OS) of patients with stage I-III CRC. In the entire cohort, the TLTW was analyzed as a continuous variable. The results suggested that TLTW (P = .003) and tumor location (P = .04) could be independent prognostic factors for patients with CRC. In addition, TLTW had an intimate relationship with tumor location (P < 0.001) and differentiation (P = .003). The mean TLTW of the right colon was significantly larger than mean TLTW of the left colon and rectal cancers. However, the mean TLTW of the left colon cancer was similar to that of the rectal cancer TLTW (P > 0.05, not shown). Subgroup analysis of TLTW according to tumor location suggested that TLTW was an independent prognostic factor for patients with right colon cancer (RCC) (P = .007) rather than left colon cancer (LCC) (P = .49) or rectal cancer (P = .16). Kaplan-Meier (K-M) analysis based on tumor location suggested that the survival rate of RCC patients had a distinctly higher trend rate than LCC patients and RECC patients in the long-term rather than in the short-term. TLTW is closely associated with tumor location in CRC. In addition, TLTW may be an independent prognostic factor for patients with RCC.

Oncological impact of vascular invasion in colon cancer might differ depending on tumor sidedness

Purpose

Vascular invasion is a well-known independent prognostic factor in colon cancer and tumor sidedness is also being considered a prognostic factor. The aim of this study was to compare the oncological impact of vascular invasion depending on the tumor location in stages I to III colon cancer.

Methods

A retrospective analysis was performed using data from patients who underwent curative resection between 2004 and 2015. Patients were divided into right-sided colon cancer (RCC) and left-sided colon cancer (LCC) groups according to the tumor location. Disease-free survival (DFS) and overall survival (OS) were compared between the RCC and LCC groups, depending on the presence of vascular invasion.

Results

A total of 793 patients were included, of which 304 (38.3%) had RCC and 489 (61.7%) had LCC. DFS and OS did not differ significantly between the RCC and LCC groups. Vascular invasion was a poor prognostic factor for DFS in both RCC (hazard ratio [HR], 2.291; 95% confidence interval [CI], 1.186–4.425; p = 0.010) and LCC (HR, 1.848; 95% CI, 1.139–2.998; p = 0.011). Additionally, it was associated with significantly worse OS in the RCC (HR, 3.503; 95% CI, 1.681–7.300; p < 0.001), but not in the LCC group (HR, 1.676; 95% CI, 0.885–3.175; p = 0.109). Multivariate analysis revealed that vascular invasion was independently poor prognostic factor for OS in the RCC (HR, 3.186; 95% CI, 1.391–7.300; p = 0.006).

Conclusion

This study demonstrated that RCC with vascular invasion had worse OS than LCC with vascular invasion.

Early-onset colorectal cancer: why it should be high on our list of differentials

Background

Early‐onset colorectal cancer (EOCRC) (<50 years) incidence has increased in Australia and worldwide. However, the diagnosis of EOCRC is often delayed. Recent research has discovered some differences from later‐onset colorectal cancer (LOCRC) (>50 years). An awareness of the unique features of EOCRC is crucial to reduce time from symptom onset to diagnosis.

Methods

A literature search was conducted on electronic databases (MEDLINE, EMBASE and Cochrane Library) using the search terms “early onset colorectal cancer” or “young onset colorectal cancer.”

Results

The American Cancer Society has reduced the colorectal cancer screening initiation age to 45 for average‐risk adults whilst screening programmes in the United Kingdom and Australia remain unchanged with initiation at 60 and 50, respectively. Exposures resulting in dysbiosis (obesity, westernised diet, alcohol, antibiotic and sugar‐sweetened beverage consumption) have been linked with increased EOCRC risk. EOCRC is often left‐sided presenting with rectal bleeding, altered bowel habit and constitutional symptoms. EOCRC is more commonly sporadic than hereditary, harbouring different genetic mutations than LOCRC. Comparative survival outcomes of EOCRC and LOCRC are conflicting with studies suggesting either better or poorer survival. Young patients better tolerate treatment‐related toxicities, which may account for their improved survival despite comparatively advanced stages and poorer histopathological features at diagnosis.

Conclusion

Current EOCRC literature is limited by American‐focused datasets and heterogenous EOCRC definitions and study designs (the greatest strength of evidence exists for EOCRC risk factor studies comprised of large retrospective cohorts). There is minimal research into the quality of life and surgical outcomes of EOCRC patients, and this area warrants further investigation.

Effect of combined epidural-general anesthesia on long-term survival of patients with colorectal cancer: a meta-analysis of cohort studies

PURPOSE

This study aimed to analyze the long-term survival of patients with colorectal cancer after receiving combined epidural-general anesthesia (EGA) or general anesthesia (GA) alone.

METHODS

The PubMed, MEDLINE, Web of Science, Cochrane Library, and Embase databases were used to search for cohort studies that explored the differences between the effects of EGA and GA on overall survival (OS) and recurrence-free survival (RFS) of patients with colorectal cancer. The hazard ratios (HRs) and their 95% confidence intervals (95%CIs) were used as indicators to evaluate the strength of the effects and were pooled.

RESULTS

Nine studies were included in the meta-analysis. EGA improved the OS of patients with colorectal cancer compared with GA (HR = 0.904, 95%CI 0.871-0.938, P < 0.05). In the subgroup analysis, EGA was more protective for OS of patients with colon cancer than GA (HR = 0.840, 95%CI 0.732-0.963, P < 0.05), but not for OS of patients with rectal cancer (HR = 0.764, 95%CI 0.398-1.469, P > 0.05). Additionally, EGA could not further prolong RFS in patients with colorectal cancer (HR = 1.015, 95%CI 0.942-1.093, P > 0.05), which was the same in the subgroup analysis of patients with colon cancer (HR = 0.908, 95%CI 0.760-1.085, P > 0.05).

CONCLUSION

EGA could improve the OS of patients with colorectal cancer, especially those with colon cancer, but it could not improve the OS in the subgroup of patients with rectal cancer. This difference may be due to the immune protective function of the parasympathetic nerve innervating the intestinal tubes above the splenic flexure retained by EGA. Additionally, although EGA has a protective effect on RFS in patients with colorectal cancer, the difference was not significant.  The design of this analysis is registered and displayed in the PROSPERO database (CRD42021274864).

Colorectal Cancer Prevalence and Survival in Cuenca (Spain)

BACKGROUND

Colorectal cancer is the most commonly diagnosed cancer type and the second cause of cancer death in Spain. The primary risk factor for colorectal cancer is age, with 90% of all diagnosed patients aged over 50 years. Prognosis mainly depends on tumour stage.

AIM

Conduct a colorectal cancer prevalence and survival study in Cuenca (Spain) since there are almost no studies based on small populations. This is the first study about survival in screening of colorectal cancer carried out in hospitals in Castilla-La Mancha.

METHODS

Retrospective descriptive cohort study was performed to include patients with colorectal cancer diagnosed by colonoscopy between May 2015 and April 2016, and who were followed up for 48 months. The study considered sociodemographic and clinical data of the patients. Survival curves were estimated using the Kaplan-Meier method. The proportional hazard rate associated with age, gender, stage, and presence of metastasis was calculated using the Cox regression method.

RESULTS

Fifty-seven patients were included in the study. The mean follow-up was 45.5 months. Ten patients died during the study; in seven cases, the cause was colorectal cancer. The percentage of patients alive at a 48-month follow-up was 82.4%.

CONCLUSION

Colon cancer is a high-prevalence pathology, with adenocarcinoma being the most common histology. The results seem to indicate that it affects men more frequently, mortality rises with tumour stage at diagnosis and declines with use of chemotherapy. We present a study that could justify large-scale epidemiological studies for the regional surveillance and evolution of colorectal cancer in Spain.

Comparison of Resected Malignant Tumors of the Right- and Left-Sided Colon—Is There a Difference?

Embryological, anatomical, and immunological differences between the right-sided and left-sided colons are well known, but the difference in oncological behavior of colon tumors has only recently become the main subject of studies. Published articles propose that there is a difference not only in symptoms, but also in survival. Our aim was to analyze the clinicopathological and oncological differences among our patients who had been operated for colon cancer in our department. We examined the historical data of our patients who underwent colon resection for malignancy between 1st of January 2016 and 31st of December 2018. Tumor markers, histological results, postoperative complications, and oncological therapies were investigated. The primary outcome was overall survival. We analyzed our patients’ survival data with Kaplan–Meier log-rank test and Cox regression analysis. In our study, 267 patients were enrolled. One hundred thirty-three (49.8%) patients had right-sided colon cancer; 134 (50.2%) patients had left-sided colon cancer. Patients with right-sided colon cancer were significantly more likely to have mucinous adenocarcinoma (p = 0.037). No significant differences were revealed in overall survival between right-sided colon cancer and left-sided colon cancer patients (p = 0.381). Additional subgroup analysis showed that there were no significant differences in overall survival for laterality neither in the metastatic group (p = 0.824) nor in the non-metastatic group (p = 0.345). Based on the conflicting previous study results, our findings repeatedly highlight that the relationship between tumor location in the colon and overall survival is not straightforward.

Socioeconomic gaps over time in colorectal cancer survival in England: flexible parametric survival analysis

BACKGROUND

Despite persistent reports of socioeconomic inequalities in colorectal cancer survival in England, the magnitude of survival differences has not been fully evaluated.

METHODS

Patients diagnosed with colon cancer (n=68 169) and rectal cancer (n=38 267) in England (diagnosed between January 2010 and March 2013) were analysed as a retrospective cohort study using the National Cancer Registry data linked with other population-based healthcare records. The flexible parametric model incorporating time-varying covariates was used to assess the difference in excess hazard of death and in net survival between the most affluent and the most deprived groups over time.

RESULTS

Survival analyses showed a clear pattern by deprivation. Hazard ratio of death was consistently higher in the most deprived group than the least deprived for both colon and rectal cancer, ranging from 1.08 to 1.17 depending on the model. On the net survival scale, the socioeconomic gap between the most and the least deprived groups reached approximately -4% at the maximum (-3.7%, 95% CI -1.6 to -5.7% in men, -3.6%, 95% CI -1.6 to -5.7% in women) in stages III for colon and approximately -2% (-2.3%, 95% CI -0.2 to -4.5% in men, -2.3%, 95% CI -0.2 to -4.3% in women) in stage II for rectal cancer at 3 years from diagnosis, after controlling for age, emergency presentation, receipt of resection and comorbidities. The gap was smaller in other stages and sites. For both cancers, patients with emergency presentation persistently had a higher excess hazard of death than those without emergency presentation.

CONCLUSION

Survival disparities were profound particularly among patients in the stages, which benefit from appropriate and timely treatment. For the patients with emergency presentation, excess hazard of death remained high throughout three years from the diagnosis. Public health measures should be taken to reduce access inequalities to improve survival disparities.

Activation of the Adipose Tissue NLRP3 Inflammasome Pathway in Cancer Cachexia

Background

Cachexia is a paraneoplastic syndrome that accompanies and compromises cancer treatment, especially in advanced stages, affecting the metabolism and function of several organs. The adipose tissue is the first to respond to the presence of the tumor, contributing to the secretion of factors which drive the systemic inflammation, a hallmark of the syndrome. While inflammation is a defensive innate response, the control mechanisms have been reported to be disrupted in cachexia. On the other hand, little is known about the role of NLRP3 inflammasome in this scenario, a multiprotein complex involved in caspase-1 activation and the processing of the cytokines IL-1β and IL-18.

Aim

based on the evidence from our previous study with a rodent model of cachexia, we examined the activation of the NLRP3 inflammasome pathway in two adipose tissue depots obtained from patients with colorectal cancer and compared with that another inflammatory pathway, NF-κB.

Results

For CC we found opposite modulation in ScAT and PtAT for the gene expression of TLR4, Caspase-1 (cachectic group) and for NF-κB p50, NF-κB p65, IL-1β. CD36, expression was decreased in both depots while that of NLRP3 and IL-18 was higher in both tissues, as compared with controls and weight stable patients (WSC). Caspase-1 basal protein levels in the ScAT culture supernatant were higher in WSC and (weight stable patients) CC, when compared to controls. Basal ScAT explant culture medium IL-1β and IL-18 protein content in ScAT supernatant was decreased in the WSC and CC as compared to CTL explants.

Conclusions

The results demonstrate heterogeneous responses in the activation of genes of the NLRP3 inflammasome pathway in the adipose tissue of patients with cancer cachexia, rendering this pathway a potential target for therapy aiming at decreasing chronic inflammation in cancer.

Characteristics of Early-Onset vs Late-Onset Colorectal Cancer: A Review

Importance

The incidence of early-onset colorectal cancer (younger than 50 years) is rising globally, the reasons for which are unclear. It appears to represent a unique disease process with different clinical, pathological, and molecular characteristics compared with late-onset colorectal cancer. Data on oncological outcomes are limited, and sensitivity to conventional neoadjuvant and adjuvant therapy regimens appear to be unknown. The purpose of this review is to summarize the available literature on early-onset colorectal cancer.

Observations

Within the next decade, it is estimated that 1 in 10 colon cancers and 1 in 4 rectal cancers will be diagnosed in adults younger than 50 years. Potential risk factors include a Westernized diet, obesity, antibiotic usage, and alterations in the gut microbiome. Although genetic predisposition plays a role, most cases are sporadic. The full spectrum of germline and somatic sequence variations implicated remains unknown. Younger patients typically present with descending colonic or rectal cancer, advanced disease stage, and unfavorable histopathological features. Despite being more likely to receive neoadjuvant and adjuvant therapy, patients with early-onset disease demonstrate comparable oncological outcomes with their older counterparts.

Conclusions and Relevance

The clinicopathological features, underlying molecular profiles, and drivers of early-onset colorectal cancer differ from those of late-onset disease. Standardized, age-specific preventive, screening, diagnostic, and therapeutic strategies are required to optimize outcomes.

Rate of dissemination and prognosis in early and advanced stage colorectal cancer based on microsatellite instability status: systematic review and meta-analysis

INTRODUCTION

For the past two decades, microsatellite instability (MSI) has been reported as a robust clinical biomarker associated with survival advantage attributed to its immunogenicity. However, MSI is also associated with high-risk adverse pathological features (poorly differentiated, mucinous, signet cell, higher grade) and exhibits a double-edged sword phenomenon. We performed a systematic review and meta-analysis to evaluate the rate of dissemination and the prognosis of early and advanced stage colorectal cancer based on MSI status.

METHODS

A systematic literature search of original studies was performed on Ovid searching MEDLINE, Embase, Cochrane Database of Systematic Reviews, American College of Physicians ACP Journal Club, Database of Abstracts of Reviews of Effects DARE, Clinical Trials databases from inception of database to June 2019. Colorectal cancer, microsatellite instability, genomic instability and DNA mismatch repair were used as key words or MeSH terms. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed. Data were pooled using a random-effects model with odds ratio (OR) as the effect size. Statistical analysis was performed using RevMan ver 5.3 Cochrane Collaboration.

RESULTS

From 5288 studies, 136 met the inclusion criteria (n = 92,035; MSI-H 11,746 (13%)). Overall, MSI-H was associated with improved OS (OR, 0.81; 95% CI 0.73-0.90), DFS (OR, 0.73; 95% CI 0.66-0.81) and DSS (OR, 0.69; 95% CI 0.52-0.90). Importantly, MSI-H had a protective effect against dissemination with a significantly lower rate of lymph node and distant metastases. By stage, the protective effect of MSI-H in terms of OS and DFS was observed clearly in stage II and stage III. Survival in stage I CRC was excellent irrespective of MSI status. In stage IV CRC, without immunotherapy, MSI-H was not associated with any survival benefit.

CONCLUSIONS

MSI-H CRC was associated with an overall survival benefit with a lower rate of dissemination. Survival benefit was clearly evident in both stage II and III CRC, but MSI-H was neither a robust prognostic marker in stage I nor stage IV CRC without immunotherapy.

Prognostic Factors for Survival in Transverse Colon Cancers

BACKGROUND

Transverse colon cancer (TCC) is a rare condition that accounts for 10% of all colon cancers. TCC was accepted more likely right-sided colon cancers. We aimed to investigate whether TCC differs from other colon tumors by using clinical, pathological, and molecular prognostic factors known to be important in colon cancer and if it differs in its own anatomical structure.

PATIENTS AND METHODS

We evaluated local and locally advanced TCC patients between 2007 and 2020 years for demographics data, symptoms, treatment status, and histopathological and molecular features.

RESULTS

Overall, 107 TCC patients were included in this study. According to the molecular data analysis of 44, 35, and 23 patients for MSI, RAS, and BRAF status, respectively, 7 (15.9%) were MSI-H, 13 (37.1%) were RAS mutant, and 11 (47.8%) had BRAF V600E mutation. The median follow-up time was 31.5 months. Median disease-free survival (DFS) was 5.19 months, and median OS was 88.3 months for the whole study population. The tumor stage was the most significant prognostic factor for DFS and OS. Although BRAF mutation was not a significant marker for DFS, it was an independent prognostic marker for OS (HR 3.90 95% CI 1.42-10.7). There were no statistically significant differences between proximal two-thirds and distal one-third tumor location.

CONCLUSION

TCC has molecular features and prognostic factors more likely RCC and no differences between proximal and distal sub-parts. BRAF V600E mutation status is an independent predictor of survival even in the early stages of TCC.

Predictors of lymph node metastases in patients with malignant adenomatous polyps of the colon

BACKGROUND

We sought to describe predictors of lymph node positivity in patients with malignant colon polyps to identify low risk patients who may potentially avoid radical surgery.

DESIGN

The National Cancer Database (2010-2015) was queried for all patients with malignant colonic polyps who underwent formal colonic resection. Univariate and multivariate methods were used to determine independent predictors of lymph node metastasis.

RESULTS

14,663 patients were identified. Lymph node disease was present in 9% of patients. High-grade disease, LVI, PNI, younger age, and left sided location were univariate predictors of lymph node disease. High-grade disease (OR 1.84), left sided location (OR 1.31), LVI (OR 5.79), and PNI (OR 1.70) were independent predictors, while elderly age (OR 0.64) was protective (all p-values <0.001). Elderly patients with low grade disease of the right/transverse colon without LVI/PNI had a 4.4% risk of lymph node disease. High grade, left-sided tumors with LVI, non-elderly age, had a 30% risk.

CONCLUSION

Non-elderly age, left-sided location, LVI, PNI and high-grade histology are independent predictors of lymph node metastasis in malignant colonic polyps.

Detection of Postcolonoscopy Colorectal Neoplasia by Multi-target Stool DNA

INTRODUCTION

Significant variability between colonoscopy operators contributes to postcolonoscopy colorectal cancers (CRCs). We aimed to estimate postcolonoscopy colorectal neoplasia (CRN) detection by multi-target stool DNA (mt-sDNA), which has not previously been studied for this purpose.

METHODS

In a retrospective cohort of patients with +mt-sDNA and completed follow-up colonoscopy, positive predictive value (PPV) for endpoints of any CRN, advanced adenoma, right-sided neoplasia, sessile serrated polyps (SSP), and CRC were stratified by the time since previous colonoscopy (0-9, 10, and ≥11 years). mt-sDNA PPV at ≤9 years from previous average-risk screening colonoscopy was used to estimate CRN missed at previous screening colonoscopy.

RESULTS

Among the 850 studied patients with +mt-sDNA after a previous negative screening colonoscopy, any CRN was found in 535 (PPV 63%). Among 107 average-risk patients having +mt-sDNA ≤9 years after last negative colonoscopy, any CRN was found in 67 (PPV 63%), advanced neoplasia in 16 (PPV 15%), right-sided CRN in 48 (PPV 46%), and SSP in 20 (PPV 19%). These rates were similar to those in 47 additional average risk persons with previous incomplete colonoscopy and in an additional 68 persons at increased CRC risk. One CRC (stage I) was found in an average risk patient who was mt-sDNA positive 6 years after negative screening colonoscopy.

DISCUSSION

The high PPV of mt-sDNA 0-9 years after a negative screening colonoscopy suggests that lesions were likely missed on previous examination or may have arisen de novo. mt-sDNA as an interval test after negative screening colonoscopy warrants further study.

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

BACKGROUND

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSION

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

Right and Left Colorectal Cancer: Differences in Post-Surgical-Care Outcomes and Survival in Elderly Patients

Simple Summary

The objective of this investigation is to analyze the differences between right and left colon cancer survival and test if these differences have transcendental importance for assistance to improve the survival and quality care of these patients. The results show that both entities are significantly different in terms of evolution, progression, complications and survival. Patients with right colon cancer have a worse prognosis, even in the early stages of the disease, due to more advanced N stages, a larger tumor size, more frequently poorly differentiated tumors and a greater positivity of lymphovascular invasion than left colon cancer. Improvement of the prognosis can be implemented mainly by reducing the specific mortality of colon cancer by achieving early detection and also stratified and personalized by location and age of onset, as well as surgical and oncological treatment of these patients.

Abstract

(1) There is evidence of the embryological, anatomical, histological, genetic and immunological differences between right colon cancer (RCC) and left colon cancer (LCC). This research has the general objective of studying the differences in outcome between RCC and LCC. (2) A longitudinal analytical study with prospective follow-up of the case–control type was conducted from 1 January 2010 to 31 December 2017 including 398 patients with 1:1 matching, depending on the location of the tumor. Inclusion criteria: programmed colectomies, 15 cm above the anal margin, adults and R0 surgery. (3) Precisely 6.8% of the exitus occurred in the first 6 months of the intervention. At 6 months, patients with LCC presented a mean survival of 7 months higher than RCC (p = 0.028). In the first stages, it can be observed that most of the exitus are for patients with RCC (stage I p = 0.021, stage II p = 0.014). In the last stages, the distribution of the deaths does not show differences between locations (stage III p = 0.683, stage IV p = 0.898). (4) The results show that RCC and LCC are significantly different in terms of evolution, progression, complications and survival. Patients with RCC have a worse prognosis, even in the early stages of the disease, due to more advanced N stages, larger tumor size, more frequently poorly differentiated tumors and a greater positivity of lymphovascular invasion than LCC.

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.

Survival of colorectal cancer patients in Brunei Darussalam: comparison between 2002-09 and 2010-17

Background

Colorectal cancer (CRC) is a major cause of cancer-related mortality worldwide. It is the second leading cause of cancer death in men and women in Brunei Darussalam in 2017, posing a major burden on society.

Methods

This retrospective cohort study (n = 1035 patients diagnosed with CRC in Brunei Darussalam from 1st January 2002 until 31st December 2017) aims to compare the overall survival rates of CRC patients (2002–2017), to compare survival rates between two study periods (2002–2009 and 2010–2017) and to identify prognostic factors of CRC. Kaplan-Meier estimator and log-rank tests were performed to analyse the overall survival rates of CRC patients. Multiple Cox regression was performed to determine the prognostic factors of CRC with adjusted hazard ratios (Adj. HRs) reported.

Results

The 1-, 3- and 5-year survival rates of CRC patients are 78.6, 62.5, and 56.0% respectively from 2002 to 2017. The 1-, 3-, and 5-year survival rates of CRC patients for 2002–2009 are 82.2, 69.6, and 64.7%; 77.0, 59.1, and 51.3% for 2010–2017 respectively. A significant difference in CRC patients’ survival rate was observed between the two study periods, age groups, ethnic groups, cancer stages, and sites of cancer (p < 0.05). The Adjusted Hazard Ratios (Adj. HRs) were significantly higher in the 2010–17 period (Adj. HR = 1.78, p < 0.001), older age group ( ≥ 60 years) (Adj. HR = 1.93, p = 0.005), distant cancer (Adj. HR = 4.69, p < 0.010), tumor at transverse colon and splenic flexure of colon (Adj. HR = 2.44, p = 0.009), and lower in the Chinese(Adj. HR = 0.63, p = 0.003).

Conclusion

This study highlights the lower survival rates of CRC patients in 2010–2017, Malays, older patients, distant cancer, and tumors located at the latter half of the proximal colon (transverse colon), and predominantly LCRC (splenic flexure, descending colon, sigmoid colon, overlapping lesion colon and colon (NOS), as well as the rectosigmoid junction and rectum (NOS)). Age, ethnicity, cancer stage, and tumor location are significant prognostic factors for CRC. These findings underscore the importance of public health policies and programmes to enhance awareness on CRC from screening to developing strategies for early detection and management, to reduce CRC-associated mortality.

Is the Effect of Tumor Localization on Prognosis Compatible with Real-life Data in Metastatic Colon Cancer? Single-Center Experience: A Retrospective Analysis

AIM

In recent years, the prognostic and predictive value of primary tumor localization in colon cancer has become increasingly important. This study aimed to retrospectively analyze the effect of colon cancer tumor localization on progression-free survival, overall survival, and response to treatments and present real-life data.

METHOD

Retrospective evaluation was made of 465 patients who were diagnosed with metastatic colorectal carcinoma between 2010 and 2015 in our clinic. The effect of primary tumor localization on progression-free survival, overall survival, and response to therapy was investigated.

RESULTS

The right colon cancer (RCC) was determined in 66 patients, 14.2% of the whole group, and left colorectal cancer (LCRC) in 399 patients which is 85.8% of patients. Mucinous adenocarcinoma was 16.7% in RCC; however, only 6.4% of LCRC had a mucinous tumor (p < 0.05). Nodal involvement in any stage (N1 and N2) was 46.9% in right colon cancer whereas in LCRC, it was 41.2% (p < 0.05). Primary tumor surgery (74.2% vs. 70.2%) and metastasectomy (33.3% vs. 19.4%) were also more common in RCC(p < 0.05). k-ras mutation status was similar in both groups (28.8% in RCC vs 26.8% in LCRC, p > 0.05). Median progression-free survival was 12.6 months in RCC, and 15.5 in LCRC (p > 0.05). Median overall survival was 28.4 months in RCC and 33.5 months in LCRC (p > 0.05). In k-ras wild-type patients, the median overall survival was 32.3 months (95% CI 25.2-39.5) in the anti-VEGF antibody treatment group and 55.1 months (95% CI 36.5-73.7) in the anti-EGFR antibody treatment group (p < 0.05).

CONCLUSION

Although tumors located in the right colon have been considered to be worse in terms of progression-free and overall survival in clinical trials, the results of this study showed that in daily practice, there was no difference between left and right colon localized tumors in progression-free and overall survival. Further, in k-ras wild-type colon cancers, tumor localization predicts the treatment response. This study is important with the presentation of real-life data and compatibility with the data of the studies to daily life.

A Prognostic Nomogram of Colon Cancer With Liver Metastasis: A Study of the US SEER Database and a Chinese Cohort

Background

Among colon cancer patients, liver metastasis is a commonly deadly phenomenon, but there are few prognostic models for these patients.

Methods

The clinicopathologic data of colon cancer with liver metastasis (CCLM) patients were downloaded from the Surveillance, Epidemiology and End Results (SEER) database. All patients were randomly divided into training and internal validation sets based on the ratio of 7:3. A prognostic nomogram was established with Cox analysis in the training set, which was validated by two independent validation sets.

Results

A total of 5,700 CCLM patients were included. Age, race, tumor size, tumor site, histological type, grade, AJCC N status, carcinoembryonic antigen (CEA), lung metastasis, bone metastasis, surgery, and chemotherapy were independently associated with the overall survival (OS) of CCLM in the training set, which were used to establish a nomogram. The AUCs of 1-, 2- and 3-year were higher than or equal to 0.700 in the training, internal validation, and external validation sets, indicating the favorable effects of our nomogram. Besides, whether in overall or subgroup analysis, the risk score calculated by this nomogram can divide CCLM patients into high-, middle- and low-risk groups, which suggested that the nomogram can significantly determine patients with different prognosis and is suitable for different patients.

Conclusion

Higher age, the race of black, larger tumor size, higher grade, histological type of mucinous adenocarcinoma and signet ring cell carcinoma, higher N stage, RCC, lung metastasis, bone metastasis, without surgery, without chemotherapy, and elevated CEA were independently associated with poor prognosis of CCLM patients. A nomogram incorporating the above variables could accurately predict the prognosis of CCLM.

Perirenal Fat Surface Area and Oncologic Outcome in Elective Colon Cancer Surgery

BACKGROUND

Central obesity is associated with surgical difficulties, but few studies explore the relationship with long-term results after colon cancer surgery.

OBJECTIVE

The purpose of this study was to investigate the association between perirenal fat surface area, a proxy for total visceral fat, and oncologic outcome after intestinal resection for colon cancer.

DESIGN

We investigated the association between perirenal fat surface area (exposure) on recurrence and death (outcome) in patients undergoing surgery with curative intent for colon cancer.

SETTINGS

The study was conducted at Stockholm South General Hospital, serving a population of 600,000.

PATIENTS

Patients (N = 733) without metastases at diagnosis who had a preoperative CT and had undergone elective colon resection between 2006 and 2016 were included.

MAIN OUTCOME MEASURES

We compared overall survival, recurrence-free survival, and cause-specific survival by perirenal fat surface area.

RESULTS

Patients with high perirenal fat surface area (fourth quartile) had more often left-sided tumors (45% vs 32% in the first quartile) and experienced more postoperative complications (29% vs 13%), but there were no differences in pathologic T and N stage, radicality of surgery, or adjuvant chemotherapy treatment. Overall survival decreased by increasing cancer stage but was not different between perirenal fat surface area categories. The HR for recurrence-free survival per centimeter squared increase in perirenal fat surface area was 1.00 (95% CI, 0.99-1.01) adjusted for age, sex, ASA category, tumor location, and postoperative complication Clavien-Dindo ≥2. The cumulative incidence of recurrence with death as a competing risk was not statistically different between perirenal fat surface area categories (p = 0.06). Subgroup analyses showed a nonsignificant tendency for men with low perirenal fat surface area to have a lower risk of recurrence and women a higher risk.

LIMITATIONS

In all register-based studies there can be randomly distributed errors. The results can only be generalized to colon resections. Our cohort ranged over a large year span.

CONCLUSIONS

We found no association between perirenal fat surface area and overall survival, recurrence-free survival, or cause-specific cumulative incidence of recurrence in patients undergoing colon resection for cancer. See Video Abstract at http://links.lww.com/DCR/B326.

LA SUPERFICIE DE GRASA PERIRRENAL Y EL RESULTADO ONCOLGICO EN CIRUGA ELECTIVA DE CNCER DE COLON

ANTECEDENTES:La obesidad central está asociada con dificultades quirúrgicas, pero pocos estudios exploran la relación de los resultados a largo plazo después de cirugía de cáncer de colon.OBJETIVO:Investigar la asociación entre la superficie de la grasa perirrenal, como un indicador de la grasa visceral total y el resultado oncológico después de una resección intestinal por cáncer de colon.DISEÑO:Se estudió la asociación entre el área de la superficie de la grasa perirrenal (expuesta) con la recurrencia y la muerte (resultado) de pacientes sometidos a cirugía con intención curativa por cáncer de colon.AJUSTES:Atención brindada por el Hospital General del Sur de Estocolmo a una población de 600,000 habitantes.PACIENTES:Aquellos pacientes sin metástasis (n = 733) en el momento del diagnóstico que tuvieron una tomografía computada preoperatoria y que se sometieron a una resección electiva de colon entre 2006-2016.PRINCIPALES MEDIDAS DE RESULTADO:Comparamos la sobrevida general, la sobrevida libre de recurrencia y la sobrevida específica de la causa, por área de superficie de grasa perirrenal.RESULTADOS:Los pacientes con una mayor área de superficie de grasa perirrenal (cuarto cuartil) tuvieron más frecuentemente tumores del lado izquierdo (45% frente a 32% en el primer cuartil) y sufrieron más complicaciones postoperatorias (29% frente a 13%), pero no hubieron diferencias en el Estadío patológico T y N, ni en lo radical de la cirugía o del tratamiento de quimioterapia adyuvante. La supervivencia general disminuyó al aumentar el estadio del cáncer, pero no fue diferente entre las categorías de área de superficie grasa perirrenal. La razón de riesgo para la sobrevida libre de recurrencia por aumento de cm2 en el área de la superficie grasa perirrenal fue de 1.00 (intervalo de confianza del 95%: 0.99-1.01) ajustada por edad, sexo, categoría de la Sociedad Americana de Anestesiólogos, ubicación del tumor y complicación postoperatoria según Clavien-Dindo ≥ 2) La incidencia acumulada de recurrencia con muerte como un riesgo competitivo no fue estadísticamente diferente entre las categorías de área de superficie grasa perirrenal (p = 0.06). Los análisis de subgrupos mostraron una tendencia no significativa para que los hombres con un área de superficie menor en grasa perirrenal tengan un menor riesgo de recurrencia y las mujeres un mayor riesgo.LIMITACIONES:En todos los estudios basados en registros puede haber errores distribuidos aleatoriamente. Los resultados solo pueden generalizarse a resecciones de colon. Nuestra cohorte osciló durante un gran lapso de años.CONCLUSIONES:No se encontró asociación entre el área de superficie de la grasa perirrenal y la sobrevida general, ni con la sobrevida libre de recurrencia o la incidencia acumulada de recurrencia específica de la causa en pacientes sometidos a resección de colon por cáncer. Consulte Video Resumen en http://links.lww.com/DCR/B326. (Traducción-Dr Xavier Delgadillo).

Red Blood Cell Distribution Width (RDW) Correlates to the Anatomical Location of Colorectal Cancer. Implications for Clinical Use

PURPOSE

The pathological, clinical, and therapeutic features of colorectal cancer (CRC) depend on its anatomical localization. We investigated possible associations between the red blood cell distribution width (RDW) and CRC localization.

METHODS

Two-hundred eighty-eight consecutive patients with CRC were retrospectively studied. Demographic, clinical, pathological and laboratory data were retrieved from clinical records and reports.

RESULTS

Median RDW values were significantly higher in patients with right-sided CRC when compared to those with CRC in other localizations (16.2, IQR: 14.5-20.0 vs 13.8, IQR: 13.0-16.1, p < 0.0001). Anisocytosis was statistically associated to haemoglobin (Hb), mean haemoglobin concentration (MHC), and mean corpuscular volume (MCV) values in all the patient groups examined. A cut-off value of 14.3% was associated with right-sided localization with sensitivity and specificity of 76.3% and 64.2%, respectively (AUC 0.71).

CONCLUSION

Median RDW values were significantly higher in right-sided CRC when compared to other tumour locations, and may represent an additional marker for differential diagnosis.

Characterization of genomic alterations in Chinese colorectal cancer patients

OBJECTIVE

Colorectal cancer is one of the most prevalent types of cancer worldwide. Right-sided and left-sided colorectal cancer (RCC and LCC) patients respond differently to treatment. We aimed to identify the different mutational profile between RCC and LCC and provided evidence for future precision therapy.

METHODS

A total of 630 Chinese colorectal cancer patients, including 467 (74.1%) LCC and 163 (25.9%) RCC, were enrolled in this cohort. Both formalin-fixed paraffin-embedded tumor tissues and matching blood samples were collected and deep sequenced targeting 450 cancer genes for genomic alteration analysis. Tumor mutational burden was measured by an algorithm developed in-house. Correlation analysis was performed by Fisher's exact test.

RESULTS

The most common mutated genes were TP53 (77.0%), APC (71.7%), KRAS (50.0%), SMAD4 (19.8%), PIK3CA (18.3%), FBXW7 (17.5%), TCF7L2 (12.5%), SOX9 (11.3%), LRP1B (10.8%), ARID1A (10.3%) and FAT4 (10.3%). The mutation frequencies of TP53 and APC in LCC were significantly higher than that of RCC, while the mutation frequency of PIK3CA was lower than that of RCC. Six gene fusions were specifically detected in RCC patients. Colorectal cancer sites were associated with gender (P = 4.15 × 10-5) and tumor differentiation (P = 0.059). In LCC, the gender-associated genes were FAT4, EP300, FAT1, LRP1, ARID1B, AR, FYN and TAF1, while in RCC, they were ARID1A, SMARCA4, LRP1 and GRIN2A. The mutations of 18 genes were associated with tumor differentiation (8 for LCC and 10 for RCC). High tumor mutational burden was more common in RCC. Our results implied more potential targeted drug therapy opportunities for RCC.

CONCLUSION

We describe the different molecular characteristics of LCC and RCC. Our result supported a better prognosis of RCC than LCC in Chinese colorectal cancer patients.

Examining More Lymph Nodes May Improve the Prognosis of Patients With Right Colon Cancer: Determining the Optimal Minimum Lymph Node Count

OBJECTIVES

The objective is to determine the optimal minimum lymph node examination number for right colon cancer (RCC) patients.

METHODS

We comprehensively analysed the Surveillance, Epidemiology and End Results database data from 2004 to 2016 to determine the 13-year trend in the number of lymph nodes examined among 108,703 left colon cancer and 165,937 RCC patients. 133,137 RCC patients eligible for inclusion were used to determine the optimal minimum for lymph node examination. We used restricted cubic splines to analyse the dose-response relationship between the number of lymph nodes examined and prognosis. X-tiles and decision trees were used to determine the optimal cutoff for the number of lymph nodes based on the survival outcomes of patients with RCC. The Kaplan-Meier method and COX model were used to estimate the overall survival and independent prognostic factors, and a prediction model was constructed. The C-index, calibration curve, net reclassification improvement and integrated discrimination improvement were used to determine the predictive performance of the model, and decision curve analysis was used to evaluate the benefits.

RESULTS

Lymph node examinations were common among colon cancer patients over the 13-year study period. It is generally agreed that at least 12 lymph nodes must be examined to ensure proper dissection and accurate staging of RCC; however, the optimal number of lymph nodes to be examined is controversial. The dose-response relationship indicated that 12 was not the optimal minimum number of lymph nodes for RCC patients. X-tile and survival decision-tree analysis indicated that 20 nodes was the optimal number. Survival analysis indicated that <20 nodes examined was a risk factor for poor prognosis, and the classification performance was superior for 20 nodes compared to 12 nodes.

CONCLUSION

Lymph node examination in RCC patients should be altered. Our research suggests that a 20-node measure may be more suitable for RCC patients.

Better survival of right-sided than left-sided stage II colon cancer: a propensity scores matching analysis based on SEER database

BACKGROUND/AIMS

Most studies have found that right-sided colon cancer (RCC) has worse prognosis than left-sided colon cancer (LCC), especially in stage III, but the reported prognosis of stage II colon cancer is variable. This study aimed to evaluate the impact of tumor location on survival outcomes in stage II colon cancer.

MATERIALS AND METHODS

Patients with stage II colon cancer were identified in the Surveillance, Epidemiology, and End Results database from 2004 to 2009. The effect of tumor location on overall survival and cancer-specific survival was analyzed using Cox proportional hazards regression models and propensity score matching.

RESULTS

Of 16,519 patients, 69.6% had RCC and30.4% had LCC. In unadjusted analyses, RCC had a 13% increased overall mortality risk (hazards ratio [HR], 1.13; 95% confidence interval [CI], 1.07-1.19; p<0.001) but an18% reduction in cancer-specific mortality risk compared with LCC (HR, 0.82; 95% CI, 0.76-0.89; p<0.001). After propensity scores matching analyses, RCC had a 21% reduced overall mortality risk (HR, 0.79; 95% CI, 0.72-0.87; p<0.001) and a 49% reduction in cancer-specific mortality risk compared with LCC (HR, 0.51; 95% CI, 0.44-0.60; p<0.001).

CONCLUSION

When adjusted for multiple clinicopathological features, stage II RCC showed better prognosis than stage II LCC.

Caspase dependent apoptotic activity of polycyclic cage-like heterocyclic hybrids

A small library of cage-like heterocyclic hybrids encompassing pyrroloisoquinolines, pyridinone and acenaphthene structural moieties have been synthesized and tested for their potential as anticancer agents against HCT116 and JURKAT cell lines. The results revealed that these cell lines are more sensitive towards compound 1g and it showed dose dependent cytotoxic effect at 48 hrs of incubation. The IC₅₀ values of compound 1g against HCT116 and JURKAT cell lines are 12.14 ± 1.53 and 10.68 ± 0.68 µM, respectively. Further studies on the determination of mechanism of action of compound 1g discovered that it brought the cell death by inducing Caspase 3 dependent apoptosis and also by arresting the cell cycle at S phase. These studies revealed that compound 1g can be recommended as a potential anti-cancer agent.

Impact of Primary Tumor Location on Survival After Curative Resection in Patients with Colon Cancer: A Meta-Analysis of Propensity Score-Matching Studies

BACKGROUND

Recent retrospective subgroup analyses of patients with unresectable colon cancer (CC) receiving systemic chemotherapy have demonstrated that there is a significant difference in treatment outcome between patients with right-sided CC (RSCC) and those with left-sided CC (LSCC). However, it is impossible to divide patients with CC randomly into RSCC and LSCC groups before surgery. Therefore, the aim of this study is to explore the impact of primary tumor location (PTL) on survival after curative surgery for patients with CC using propensity score-matching (PSM) studies instead of randomization.

MATERIALS AND METHODS

We performed a comprehensive electronic search of the literature up to January 2019 to identify studies that had used databases allowing comparison of postoperative survival between patients with RSCC and those with LSCC. To integrate the impact of PTL on 5-year overall survival (OS) after curative surgery, a meta-analysis was performed using random-effects models to calculate the risk ratio (RR) and 95% confidence interval (CI) for the selected PSM studies.

RESULTS

Five studies involving a total of 398,687 patients with CC were included in this meta-analysis. Among 205,641 patients with RSCC, 69,091 (33.6%) died during the observation period, whereas among 193,046 patients with LSCC, 63,380 (32.8%) died during the same period. These results revealed that patients with RSCC and those with LSCC had almost the same 5-year OS (RR, 0.98; 95% CI, 0.89-1.07; p = .64; I² = 97%).

CONCLUSION

This meta-analysis has demonstrated that there was no significant difference in 5-year OS between patients with RSCC and those with LSCC after curative resection.

IMPLICATIONS FOR PRACTICE

To integrate the impact of primary tumor location (PTL) on 5-year overall survival (OS) after curative surgery, five propensity score-matching (PSM) studies involving a total of 398,687 patients with colon cancer (CC) were included in this meta-analysis. Among 205,641 patients with right-sided CC (RSCC), 69,091 (33.6%) died during the observation period, whereas among 193,046 patients with left-sided CC (LSCC), 63,380 (32.8%) died during the same period. These results revealed that patients with RSCC and those with LSCC had almost the same 5-year OS (risk ratio, 0.98; 95% confidence interval, 0.89-1.07; p = .64; I² = 97%).

The prognosis and recurrence pattern of right- and left- sided colon cancer in Stage II, Stage III, and liver metastasis after curative resection

Purpose

Primary tumor location of colon cancer has been reported to affect the prognosis after curative resection. However, some reports suggested the impact was varied by tumor stage. This study analyzed the prognostic impact of the sidedness of colon cancer in stages II, III, and liver metastasis after curative resection using propensity-matched analysis.

Methods

Right-sided colon cancer was defined as a tumor located from cecum to splenic flexure, while any more distal colon cancer was defined as left-sided colon cancer. Patients who underwent curative resection at Nara Medical University hospital between 2000 and 2016 were analyzed.

Results

There were 110 patients with stage II, 100 patients with stage III, and 106 patients with liver metastasis. After propensity matching, 28 pairs with stage II and 32 pairs with stage III were identified. In the patients with stage II, overall survival (OS) and recurrence-free survival (RFS) were not significantly different for right- and left-sided colon cancers. In the patients with stage III, OS and RFS were significantly worse in right-sided colon cancer. In those with liver metastasis, OS of right-sided colon cancer was significantly worse than left-sided disease, while RFS was similar. Regarding metachronous liver metastasis, the difference was observed only in the patients whose primary colon cancer was stage III. In each stage, significantly higher rate of peritoneal recurrence was found in those with right-sided colon cancer.

Conclusion

Sidedness of colon cancer had a significant and varied prognostic impact in patients with stage II, III, and liver metastasis after curative resection.

The Real-Life Data of BRAF Mutation on the Treatment of Colorectal Cancer: a TOG Study

PURPOSE

Colorectal cancer is the third leading diagnosis accounting for nearly 10% of all new cancers worldwide. The distinct features among BRAF mutant colorectal cancers make these tumor groups hard to treat for oncologists. The median overall survival (OS) of these types of cancers is reported to be 9 to 14 months.

METHODS

The study was declared on the Turkish Oncology Study Group Conference and approved. The patients' data was received from the centers who confirmed to participate. The BRAF-mutated patients were included in the study. The demographic features (age, gender, etc.), type of mutation, tumor localizations, histology, microsatellite instability (MSI) status, metastasis patterns chemotherapeutic agents and progression, and death times were recorded.

RESULTS

Thirty-nine patients were enrolled in the study. Sixteen patients had concurrent KRAS mutations, while 7 had NRAS mutations. Most of the patients received doublet chemotherapies in combination with anti-VEGF agents in the first and second line of the treatment. There was a significant difference in OS according to the stage which showed a decreased survival in stage IV patients at the time of diagnosis. Concurrent KRAS mutation resulted in increased OS. The median OS was 47 and 24 months favoring the KRAS mutant group. The patients whose primary tumor operated had better survival when compared with other patients. The median OS of the operated group was 47 months, while the non-operated group was 24 months. Liver metastasis was related to worse prognosis at the time of diagnosis in univariate analysis.

CONCLUSION

In our study we found a high concurrent RAS mutation ratio in a BRAF mutant patient group which was different from prior studies. The concurrent mutations resulted in a favorable outcome in terms of OS which is also different from the current knowledge. More prospective studies are needed especially BRAF-mutated patient population and especially with concurrent RAS mutations.

PKM2 Expression as Biomarker for Resistance to Oxaliplatin-Based Chemotherapy in Colorectal Cancer

The purpose of the current study is to investigate the prognostic significance of M2 isoform of pyruvate kinase (PKM2) mRNA expression loss in patients with operable colon cancer (CC). Two hundred sixty-two specimens from patients with stage-III or high-risk stage-II CC (group-A) treated with adjuvant fluoropyrimidine and oxaliplatin chemotherapy (FOLFOX), 118 specimens from metastatic CC patients (group-B) treated with FOLFOX, and 104 metastatic CC patients (group-C) treated with irinotecan-based chemotherapy were analyzed for PKM2, TS, ERCC1, MYC, and NEDD9 mRNA expression, as well as KRAS exon2 and BRAF^V600E mutations. High PKM2 mRNA expression was correlated with left-sided located primaries (p = 0.001, group-A; p = 0.003, group-B; p = 0.001, group-C), high-grade tumors (p = 0.001, group-A; p = 0.017, group-B; p = 0.021, group-C), microsatellite-stable tumors (p < 0.001, group-A), pericolic lymph nodes involvement (p = 0.018, group-A), and cMYC mRNA expression (p = 0.002, group-A; p = 0.008, group-B; p = 0.006, group-C). High PKM2 mRNA expression was correlated with significantly lower disease free survival (DFS) (p = 0.002) and overall survival (OS) (p = 0.001) in the group-A. Similarly, PKM2 mRNA expression was associated with significantly decreased progression free survival (PFS) (p = 0.001) and OS (p = 0.001) in group-B. On the contrary, no significant association for the PKM2 mRNA expression has been observed with either PFS (p = 0.612) or OS (p = 0.517) in group-C. To conclude, the current study provides evidence for the prediction of PKM2 mRNA expression oxaliplatin-based treatment resistance.

Early-onset colorectal cancer: initial clues and current views

Over the past several decades, the incidence of early-onset colorectal cancer (EOCRC; in patients <50 years old) has increased at an alarming rate. Although robust and scientifically rigorous epidemiological studies have sifted out environmental elements linked to EOCRC, our knowledge of the causes and mechanisms of this disease is far from complete. Here, we highlight potential risk factors and putative mechanisms that drive EOCRC and suggest likely areas for fruitful research. In addition, we identify inconsistencies in the evidence implicating a strong effect of increased adiposity and suggest that certain behaviours (such as diet and stress) might place nonobese and otherwise healthy people at risk of this disease. Key risk factors are reviewed, including the global westernization of diets (usually involving a high intake of red and processed meats, high-fructose corn syrup and unhealthy cooking methods), stress, antibiotics, synthetic food dyes, monosodium glutamate, titanium dioxide, and physical inactivity and/or sedentary behaviour. The gut microbiota is probably at the crossroads of these risk factors and EOCRC. The time course of the disease and the fact that relevant exposures probably occur in childhood raise important methodological issues that are also discussed.

Histology and its prognostic effect on KRAS-mutated colorectal carcinomas in Korea

KRAS mutation is frequently identified in advanced colorectal carcinoma (CRC); however, its prognostic significance and the associated histological features have remained to be clarified. In the present study, the precise histological results and prognostic value of KRAS-mutated CRCs were investigated in patients from South Korea. A retrospective review of the results from KRAS mutation testing, as well as evaluation of the histology of 310 cases of CRC at various stages, were performed. Cross-tabulation and survival analysis were performed according to the KRAS status. Patients with KRAS mutation more frequently exhibited serrated and papillary architectures (P=0.009 and P=0.014, respectively). KRAS mutation was an independent unfavorable prognostic factor for overall survival (OS) according to multivariate analysis (P=0.001), whereas no association was observed with disease-free survival (DFS) (P=0.611). Of note, in the subgroup of KRAS-mutated carcinomas, the presence of a solid component on histology was associated with less favorable OS (P=0.032). Furthermore, among the wild type cases, patients with a micropapillary component had a worse OS than those who did not (P=0.018). However, no subgroup or specific histological features were associated with DFS. In summary, KRAS-mutated CRCs had a moderate association with particular histological features, and according to the KRAS mutational status, there was a certain degree of association between histology and prognosis.

The Prognostic Value of the Detection of Microbial Translocation in the Blood of Colorectal Cancer Patients

Dysbiosis has been associated with various diseases and is of major health importance. Dysbiosis leads to microbial translocation, which is the passage of microorganisms, their fragments, or their metabolites from the intestinal lumen into the blood circulation and other sites. The aim of the study was to determine whether microbial translocation occurs in stage II/III-IV colorectal cancer (CRC) patients. The aim was also to evaluate the usefulness of blood PCR for diagnosis of such translocation and correlate the presence of toll-like receptor/vitamin D receptor (TLR/VDR) gene polymorphisms with microbial DNA fragments detected in the blood of CRC patients. Three hundred and ninety-seven CRC patients enrolled in the study. Peripheral blood DNA was analyzed using PCR for the amplification of genomic DNA encoding 16S rRNA, the β-galactosidase gene of Escherichia coli, glutamine synthase gene of Bacteroides fragilis, and 5.8S rRNA of Candida albicans. Significantly higher rates of all microbial fragments, but E. coli, detected were observed in the CRC patients (p < 0.001); such detection of all four microbial fragments was also significantly associated with the metastatic disease (p < 0.001), leading to shorter survival rates (p < 0.001). Tumor location in the right colon also significantly correlated with shorter survival (p = 0.016). Individuals with homozygous mutant alleles of TLR/VDR polymorphisms had significantly higher detection rates of microbial DNA fragments. The detection of microbial DNA fragments in CRC patients highlighted the role of these microbes in cancer development, progression, and patients' survival.

Differences in oncological outcomes and inflammatory biomarkers between right-sided and left-sided stage I-III colorectal adenocarcinoma

BACKGROUND

The aim of this study was to investigate the differences in oncological outcome and inflammatory biomarkers between right-sided colon cancer (RCC) and left-sided colorectal cancer (LCRC).

METHODS

We retrospectively analyzed 339 patients with stage I-III colorectal cancer, including 125 RCC patients and 214 LCRC patients, who underwent radical resection from January 2012 to January 2014. Comparison of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) between RCC and LCRC was evaluated using the Mann-Whitney U test. Overall survival (OS) and disease-free survival (DFS) were analyzed using Kaplan-Meier analysis and compared using the log-rank test. Univariate and multivariate Cox regression analyses were used to identify the prognostic value of inflammatory markers.

RESULTS

Patients with RCC had higher NLR (P = .002) and PLR (P < .001) but lower LMR (P = .002) compared to LCRC. In stage I-III, RCC showed poorer OS and DFS than LCRC (61.6% vs 71.5%, P = .018; 64.8% vs 76.2%, P = .006). Univariate and multivariate analyses indicated that NLR, PLR, and LMR were independent predictors for both OS and DFS in RCC, whereas only PLR was found to be an independent prognostic predictor in LCRC.

CONCLUSION

The prognosis and prognostic value of inflammatory biomarkers were significantly different between RCC and LCRC. Novel therapeutic strategies are needed, and proper prognostic predictors should be selected according to colorectal tumor location.

Microbiome in Colorectal Cancer: How to Get from Meta-omics to Mechanism?

Mounting evidence from metagenomic analyses suggests that a state of pathological microbial imbalance or dysbiosis is prevalent in the gut of patients with colorectal cancer. Several bacterial taxa have been identified of which representative isolate cultures interact with human cancer cells in vitro and trigger disease pathways in animal models. However, how the complex interrelationships in dysbiotic communities may be involved in cancer pathogenesis remains a crucial question. Here, we provide a survey of current knowledge of the gut microbiome in colorectal cancer. Moving beyond observational studies, we outline new experimental approaches for gaining ecosystem-level mechanistic understanding of the gut microbiome's role in cancer pathogenesis.