Subgroups and prognostication in stage III colon cancer: future perspectives for adjuvant therapy

Addition of V-Stage to Conventional TNM Staging to Create the TNVM Staging System for Accurate Prediction of Prognosis in Colon Cancer: A Multi-Institutional Retrospective Cohort Study

We evaluated the prognostic impact of vascular invasion (VI) compared with nodal (N) stage and developed a new staging system including VI in colon cancer. Patients who underwent curative resection with stage II-III colon cancer were assigned to VI and non-VI groups; the latter was subclassified as N0, N1, and N2; a new TNVM staging was devised by adding the V-stage. Among the 2243 study participants, the VI group independently showed worse oncological outcomes than the N1 group (disease-free survival (DFS), hazard-ratio (HR) 1.704, 1.267–2.291; overall survival (OS), HR 2.301, 1.582–3.348). The 5-year DFS in the VI group was 63.4% [N1b (74.6%), p = 0.003; N2a (69.7%), p = 0.126; and N2b (56.8%), p = 0.276], and the 5-year OS was 76.6% [N1b (84.9%), p = 0.004; N2a (83.0%), p = 0.047; and N2b (76.1%), p = 0.906]. Thus, we considered VI as N2a in TNVM staging; 78 patients (3.5%) underwent upstaging. The 5-year OS rates of stage IIB and IIC increased from 88.6% and 65.9% in TNM staging to 90.5% and 85.7% in TNVM staging, respectively. In stage II–III colon cancer, VI had a similar prognostic impact as the N2 stage without VI. The incorporation of the V-stage into the conventional TNM staging facilitates better prediction of prognosis.

Clinical Implications of Nonbiological Factors With Colorectal Cancer Patients Younger Than 45 Years

Background

To evaluate the clinical implications of non-biological factors (NBFs) with colorectal cancer (CRC) patients younger than 45 years.

Methods

In the present study, we have conducted Cox proportional hazard regression analyses to evaluate the prognosis of different prognostic factors, the hazard ratios (HRs) were shown with 95% confidence intervals (CIs). Kaplan-Meier method was utilized to compare the prognostic value of different factors with the log-rank test. NBF score was established according to the result of multivariate Cox analyses.

Results

In total, 15129 patients before 45 years with known NBFs were identified from the SEER database. Only county-level median household income, marital status and insurance status were NBFs that significantly corelated with the cause specifical survival in CRC patients aged less than 45 years old (P < 0.05). Stage NBF 1 showed 50.5% increased risk of CRC-specific mortality (HR = 1.505, 95% CI = 1.411-1.606, P < 0.001). Stage NBF 0 patients were associated with significantly increased CRC-specific survival (CCSS) when compared with the stage NBF 1 patients in different AJCC TNM stages.

Conclusions

NBF stage (defined by county-level median household income, marital status and insurance status) was strongly related to the prognosis of CRC patients. NBFs should arouse enough attention of us in clinical practice of patients younger than 45 years.

LncRNA SLCO4A1-AS1 modulates colon cancer stem cell properties by binding to miR-150-3p and positively regulating SLCO4A1

Long non-coding RNAs (lncRNAs) play important roles in a range of different human cancers. However, the role of lncRNA solute carrier organic anion transporter family member 4A1-AS1 (SLCO4A1-AS1) in colon cancer remains enigmatic. Hence, we aimed to explore the specific role of SLCO4A1-AS1 in colon cancer stem cells. Colon cancer-related differentially expressed lncRNA and mRNA were screened using microarray-based analysis, and the expression of SLCO4A1-AS1 and SLCO4A1 in colon cancer tissues was determined using reverse transcription quantitative polymerase chain reaction and western blot analysis. The interaction among SLCO4A1-AS1, microRNA-150-3p (miR-150-3p) and SLCO4A1 was verified using dual-luciferase reporter assay, RNA immunoprecipitation and RNA pull-down. Moreover, SLCO4A1-AS1, miR-150-3p and/or SLCO4A1 were overexpressed or depleted in colon cancer cells to detect their effects on migration, invasion, sphere formation, apoptosis and tumorigenesis abilities of colon cancer stem CD133+CD44+ cells using both in vitro and in vivo assays. SLCO4A1-AS1 and SLCO4A1 were screened as the differentially expressed lncRNA and mRNA in colon cancer tissues. SLCO4A1-AS1 was confirmed to competitively bind to miR-150-3p to elevate SLCO4A1 expression. Moreover, knockdown of SLCO4A1-AS1 decreased SLCO4A1 expression, thus inhibiting cell migration, invasion, sphere formation, and tumorigenesis abilities and enhancing the apoptosis of CD133+CD44+ cells. Collectively, these findings provide evidence demonstrating that depleting SLCO4A1-AS1 competitively binds to miR-150-3p, which downregulates SLCO4A1 expression, thus hindering colon cancer progression.

Serum Tumor Markers Combined With Clinicopathological Characteristics for Predicting MMR and KRAS Status in 2279 Chinese Colorectal Cancer Patients: A Retrospective Analysis

Although serum tumor markers (STMs), clinicopathological characteristics and the status of KRAS and MMR play an important role in optimizing the treatment and prognosis of colorectal cancer, their interrelationships remain largely unknown. A retrospective analysis of 2279 patients who tested for KRAS and MMR status, and STM measurements prior to treatment over the past four years was conducted. Of the 784 patients tested for KRAS and 2279 patients tested for MMR status, KRAS mutations and dMMR were identified in 276 patients (35.20%) and 177 patients (7.77%), respectively. Logistic regression analysis demonstrated that right colon, well and moderate differentiation and negative CA19-9 were independent predictors for KRAS mutations. The ROC curve yielded an AUC of 0.609 through the combination of these three factors. Age < 65 was an independent predictive factor for dMMR, along with tumor size > 4.6 cm, right colon, poor differentiation, harvested lymph nodes ≥ 22, no lymph node metastasis, no perineural invasion, negative CEA and positive CA72-4. When the nine criteria were used together, the AUC was 0.849. In summary, both STMs and clinicopathological characteristics were found to be significantly associated with the status of KRAS and MMR. The combination of these two factors possessed a strong predictive power for KRAS mutations and dMMR among CRC patients.

A Serum Metabolomics Classifier Derived from Elderly Patients with Metastatic Colorectal Cancer Predicts Relapse in the Adjuvant Setting

Simple Summary

Around 30–40% of patients with early stage colorectal cancer (eCRC) experience relapse after surgery. Current recommendations for adjuvant therapy are based on suboptimal risk-stratification tools. In elderly patients, risk of relapse assessment is particularly important to ultimately avoid unnecessary chemotherapy-related toxicity in this frailer population. Serum metabolomics via NMR spectroscopy may improve risk stratification by identifying patients with residual micrometastases after surgery and thus at higher risk of relapse. We evaluated the serum metabolomic fingerprints of 94 elderly patients with eCRC (65 relapse free and 29 relapsed), and of 75 elderly patients with metastatic disease. Metabolomics efficiently discriminated patients with relapse-free eCRC from those with metastatic disease, correctly predicting relapse in 69% of relapsed eCRC patients. The metabolomic score was strongly and independently associated with prognosis. Our data suggest metabolomics as a valid addition to standard tools to refine risk stratification for eCRC and warrant further investigation.

Abstract

Adjuvant treatment for patients with early stage colorectal cancer (eCRC) is currently based on suboptimal risk stratification, especially for elderly patients. Metabolomics may improve the identification of patients with residual micrometastases after surgery. In this retrospective study, we hypothesized that metabolomic fingerprinting could improve risk stratification in patients with eCRC. Serum samples obtained after surgery from 94 elderly patients with eCRC (65 relapse free and 29 relapsed, after 5-years median follow up), and from 75 elderly patients with metastatic colorectal cancer (mCRC) obtained before a new line of chemotherapy, were retrospectively analyzed via proton nuclear magnetic resonance spectroscopy. The prognostic role of metabolomics in patients with eCRC was assessed using Kaplan–Meier curves. PCA-CA-kNN could discriminate the metabolomic fingerprint of patients with relapse-free eCRC and mCRC (70.0% accuracy using NOESY spectra). This model was used to classify the samples of patients with relapsed eCRC: 69% of eCRC patients with relapse were predicted as metastatic. The metabolomic classification was strongly associated with prognosis (p-value 0.0005, HR 3.64), independently of tumor stage. In conclusion, metabolomics could be an innovative tool to refine risk stratification in elderly patients with eCRC. Based on these results, a prospective trial aimed at improving risk stratification by metabolomic fingerprinting (LIBIMET) is ongoing.

Correlations Between Tumor Mutation Burden and Immunocyte Infiltration and Their Prognostic Value in Colon Cancer

Background

Colon cancer has a huge incidence and mortality worldwide every year. Immunotherapy could be a new therapeutic option for patients with advanced colon cancer. Tumor mutation burden (TMB) and immune infiltration are considered critical in immunotherapy but their characteristics in colon cancer are still controversial.

Methods

The somatic mutation, transcriptome, and clinical data of patients with colon cancer were obtained from the TCGA database. Patients were divided into low or high TMB groups using the median TMB value. Somatic mutation landscape, differentially expressed genes, and immune-related hub genes, Gene Ontology and KEGG, gene set enrichment, and immune infiltration analyses were investigated between the two TMB groups. Univariate and multivariate Cox analyses were utilized to construct a prognostic gene signature. The differences in immune infiltration, and the expression of HLA-related genes and checkpoint genes were investigated between the two immunity groups based on single sample gene set enrichment analysis. Finally, a nomogram of the prognostic prediction model integrating TMB, immune infiltration, and clinical parameters was established. Calibration plots and receiver operating characteristic curves (ROC) were drawn, and the C-index was calculated to assess the predictive ability.

Results

Missense mutations and single nucleotide polymorphisms were the major variant characteristics in colon cancer. The TMB level showed significant differences in N stage, M stage, pathological stage, and immune infiltration. CD8⁺ T cells, activated memory CD4⁺ T cells, activated NK cells, and M1 macrophages infiltrated more in the high-TMB group. The antigen processing and presentation signaling pathway was enriched in the high-TMB group. Two immune related genes (CHGB and SCT) were identified to be correlated with colon cancer survival (HR = 1.39, P = 0.01; HR = 1.26, P = 0.02, respectively). Notably, the expression of SCT was identified as a risk factor in the immune risk model, in which high risk patients showed poorer survival (P = 0.04). High immunity status exhibited significant correlations with immune response pathways, HLA-related genes, and immune checkpoint genes. Finally, including nine factors, our nomogram prediction model showed better calibration (C-index = 0.764) and had an AUC of 0.737.

Conclusion

In this study, we investigated the patterns and prognostic roles of TMB and immune infiltration in colon cancer, which provided new insights into the tumor microenvironment and immunotherapies and the development of a novel nomogram prognostic prediction model for patients with colon cancer.

Higher ETV5 Expression Associates With Poor 5-Florouracil-Based Adjuvant Therapy Response in Colon Cancer

Discovery of markers predictive for 5-Fluorouracil (5-FU)-based adjuvant chemotherapy (adjCTX) response in patients with locally advanced stage II and III colon cancer (CC) is necessary for precise identification of potential therapy responders. PEA3 subfamily of ETS transcription factors (ETV1, ETV4, and ETV5) are upregulated in multiple cancers including colon cancers. However, the underlying epigenetic mechanism regulating their overexpression as well as their role in predicting therapy response in colon cancer are largely unexplored. In this study, using gene expression and methylation data from The Cancer Genome Atlas (TCGA) project, we showed that promoter DNA methylation negatively correlates with ETV4 expression (ρ = -0.17, p = 5.6 × 10^-3) and positively correlates with ETV5 expression (ρ = 0.22, p = 1.43 × 10^-4) in colon cancer tissue. Further, our analysis in 1,482 colon cancer patients from five different cohorts revealed that higher ETV5 expression associates with shorter relapse-free survival (RFS) of adjCTX treated colon cancer patients (Hazard ratio = 2.09-5.43, p = 0.004-0.01). The present study suggests ETV5 expression as a strong predictive biomarker for 5-FU-based adjCTX response in stage II/III CC patients.

Loss of YY1 expression predicts unfavorable prognosis in stage III colorectal cancer

Background

Yin Yang 1 (YY1), the multifunctional transcription factor, has recently been assigned biological properties related to human malignancies. YY1 can facilitate both tumor suppression and tumor growth. The conflicting role of YY1 in human malignancies is not yet fully explained.

Objective

In this study, we determined the clinicopathologic significance and prognostic role of YY1 in stage III colorectal cancer (CRC).

Materials and Methods

YY1 expression was evaluated immunohistochemically in tissue microarray from 345 CRCs. YY1 expression was scored by the proportion of tumor cells with nuclear staining into 4 scores (0, none; 1+, ≤10%; 2+, 10 to ≤25%; 3+, >25%). A score of 0 and 1 were considered as loss of expression.

Results

Loss of YY1 expression was observed in 49 (14.2%) out of 345 CRCs and was associated with larger tumor size (P = 0.004), tumor deposit (P = 0.008), and higher pathologic tumor (pT) stage (P = 0.004). In stage III group, loss of YY1 expression was associated with larger tumor size (P = 0.027) and tumor deposit (P = 0.011). Kaplan-Meier survival curves revealed no significant difference between patients with YY1 loss and patients with intact YY1 in both cancer-specific survival and recurrence-free survival (P = 0.330 and P = 0.470, respectively). In American Joint Committee on Cancer (AJCC) stage subgroup, loss of YY1 expression was associated with poor recurrence-free survival in AJCC stage III CRC (P = 0.038).

Conclusion

Loss of YY1 expression was significantly associated with aggressive phenotypes and poor patient outcome in AJCC stage III CRC.

Prognostic and Predictive Cross-Roads of Microsatellite Instability and Immune Response to Colon Cancer

Understanding molecular features of colon cancer has shed light on its pathogenesis and progression. Over time, some of these features acquired clinical dignity and were incorporated in decision making. Namely, microsatellite instability (MSI) due to mismatch repair of defects, which primarily was adopted for the diagnosis of Lynch syndrome, became recognized as the biomarker of a different disease type, showing a less aggressive behavior. MSI tumors harbor high amounts of tumor infiltrating lymphocytes (TILs) due to their peculiar load in neoantigens. However, microsatellite stable colon cancer may also show high amounts of TILs, and this feature is as well associated with better outcomes. High TIL loads are in general associated with a favorable prognosis, especially in stage II colon cancer, and therein identifies a patient subset with the lowest probability of relapse. With respect to post-surgical adjuvant treatment, particularly in stage III, TILs predictive ability seems to weaken along with the progression of the disease, being less evident in high risk patients. Moving from cohort studies to the analysis of a series from clinical trials contributed to increase the robustness of TILs as a biomarker. The employment of high TIL densities as an indicator of good prognosis in early-stage colon cancers is strongly advisable, while in late-stage colon cancers the employment as an indicator of good responsiveness to post-surgical therapy requires refinement. It remains to be clarified whether TILs could help in identifying those patients with node-positive cancers to whom adjuvant treatment could be spared, at least in low-risk groups as defined by the TNM staging system.

FOXM1/DVL2/Snail axis drives metastasis and chemoresistance of colorectal cancer

Colorectal cancer (CRC) is the third most common type of cancer worldwide. Metastasis and chemoresistance are regarded as the two leading causes of treatment failure and high mortality in CRC. Forkhead Box M1 (FOXM1) has been involved in malignant behaviors of cancer. However, the role and mechanism of FOXM1 in simultaneously regulating metastasis and chemoresistance of CRC remain poorly understood. Here, we found that FOXM1 was overexpressed in oxaliplatin- and vincristine-resistant CRC cells (HCT-8/L-OHP and HCT-8/VCR) with enhanced metastatic potential, compared with HCT-8 cells. FOXM1 overexpression increased migration, invasion and drug-resistance to oxaliplatin and vincristine in HCT-8 cells, while FOXM1 knockdown using shFOXM1 impaired metastasis and drug-resistance in HCT-8/L-OHP and HCT-8/VCR cells. Moreover, FOXM1 up-regulated Snail to trigger epithelial-mesenchymal transition-like molecular changes and multidrug-resistance protein P-gp expression, while silencing Snail inhibited FOXM1-induced metastasis and drug-resistance. We further identified that disheveled-2 (DVL2) was crucial for FOXM1-induced Snail expression, metastasis and chemoresistance. Furthermore, FOXM1 bound to DVL2, and enhanced nuclear translocation of DVL2 and DVL2-mediated transcriptional activity of Wnt/β-catenin known to induce Snail expression. In conclusion, FOXM1/DVL2/Snail axis triggered aggressiveness of CRC. Blocking FOXM1/DVL2/Snail pathway simultaneously inhibited metastasis and chemoresistance in CRC cells, providing a new strategy for successful CRC treatment.

A Novel Seventeen-Gene Metabolic Signature for Predicting Prognosis in Colon Cancer

A metabolic disorder is considered one of the hallmarks of cancer. Multiple differentially expressed metabolic genes have been identified in colon cancer (CC), and their biological functions and prognostic values have been well explored. The purpose of the present study was to establish a metabolic signature to optimize the prognostic prediction in CC. The related data were downloaded from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx) database, and Gene Expression Omnibus (GEO) combined with GSE39582 set, GSE17538 set, GSE33113 set, and GSE37892 set. The differentially expressed metabolic genes were selected for univariate Cox regression and lasso Cox regression analysis using TCGA and GTEx datasets. Finally, a seventeen-gene metabolic signature was developed to divide patients into a high-risk group and a low-risk group. Patients in the high-risk group presented poorer prognosis compared to the low-risk group in both TCGA and GEO datasets. Moreover, gene set enrichment analyses demonstrated multiple significantly enriched metabolism-related pathways. To sum up, our study described a novel seventeen-gene metabolic signature for prognostic prediction of colon cancer.

Multicenter International Society for Immunotherapy of Cancer Study of the Consensus Immunoscore for the Prediction of Survival and Response to Chemotherapy in Stage III Colon Cancer

PURPOSE

The purpose of this study was to evaluate the prognostic value of Immunoscore in patients with stage III colon cancer (CC) and to analyze its association with the effect of chemotherapy on time to recurrence (TTR).

METHODS

An international study led by the Society for Immunotherapy of Cancer evaluated the predefined consensus Immunoscore in 763 patients with American Joint Committee on Cancer/Union for International Cancer Control TNM stage III CC from cohort 1 (Canada/United States) and cohort 2 (Europe/Asia). CD3+ and cytotoxic CD8+ T lymphocyte densities were quantified in the tumor and invasive margin by digital pathology. The primary end point was TTR. Secondary end points were overall survival (OS), disease-free survival (DFS), prognosis in microsatellite stable (MSS) status, and predictive value of efficacy of chemotherapy.

RESULTS

Patients with a high Immunoscore presented with the lowest risk of recurrence, in both cohorts. Recurrence-free rates at 3 years were 56.9% (95% CI, 50.3% to 64.4%), 65.9% (95% CI, 60.8% to 71.4%), and 76.4% (95% CI, 69.3% to 84.3%) in patients with low, intermediate, and high immunoscores, respectively (hazard ratio [HR; high v low], 0.48; 95% CI, 0.32 to 0.71; P = .0003). Patients with high Immunoscore showed significant association with prolonged TTR, OS, and DFS (all P < .001). In Cox multivariable analysis stratified by participating center, Immunoscore association with TTR was independent (HR [high v low], 0.41; 95% CI, 0.25 to 0.67; P = .0003) of patient's sex, T stage, N stage, sidedness, and microsatellite instability status. Significant association of a high Immunoscore with prolonged TTR was also found among MSS patients (HR [high v low], 0.36; 95% CI, 0.21 to 0.62; P = .0003). Immunoscore had the strongest contribution χ2 proportion for influencing survival (TTR and OS). Chemotherapy was significantly associated with survival in the high-Immunoscore group for both low-risk (HR [chemotherapy v no chemotherapy], 0.42; 95% CI, 0.25 to 0.71; P = .0011) and high-risk (HR [chemotherapy v no chemotherapy], 0.5; 95% CI, 0.33 to 0.77; P = .0015) patients, in contrast to the low-Immunoscore group (P > .12).

CONCLUSION

This study shows that a high Immunoscore significantly associated with prolonged survival in stage III CC. Our findings suggest that patients with a high Immunoscore will benefit the most from chemotherapy in terms of recurrence risk.

Development and validation of a novel metabolic signature for predicting prognosis in patients with laryngeal cancer

PURPOSE

Despite advances in the development of treatments for laryngeal cancer (LC), including surgical treatments and radio-chemotherapy, the survival rate of LC remains low. Therefore, novel metabolic signatures are urgently needed to evaluate the prognosis of LC patients.

METHODS

Differentially expressed metabolic genes were extracted via bioinformatics analysis from the raw data of The Cancer Genome Atlas and Gene Expression Omnibus (GEO) databases. Univariate Cox regression and LASSO analyses were performed to identify metabolic genes that were significantly correlated with overall survival (OS). Using the Kaplan-Meier analysis and receiver operating characteristics, the prognostic power of candidate signatures was evaluated in the two databases. Gene Set Enrichment Analysis (GSEA) was performed to explore significant signaling pathways and underlying mechanisms in the high- and low-risk groups.

RESULTS

Thirteen metabolism genes showed superior ability to predict OS for LC when compared to clinical variables, and patients in the high-risk group showed significantly poorer OS than those in the low-risk group. The area under the curve of receiver operating curves for 5- and 3-year OS was 0.929 and 0.899, respectively, which were better than the OS obtained with clinicopathological variables. Similar results obtained in the GEO cohort indicated that this gene signature could differentiate between LC patients with and without recurrence.

CONCLUSION

To our knowledge, this study is the first to report that the 13 metabolic genes could serve as an independent biomarker for LC, which could provide vital prognostic information and prediction for personalized treatment of LC.

Feasibility Study of a Modified XELOX Adjuvant Chemotherapy for High-Recurrence Risk Patients With Operated Stage III Colon Cancer

Background

Our previous study reported the favorable efficacy and good tolerance associated with a modified XELOX adjuvant chemotherapy with eight cycles of capecitabine and six cycles of oxaliplatin for operated stage III colon cancer. The current study aimed to confirm the feasibility of modified XELOX chemotherapy for treating specific high-risk (T4, N2, or both) stage III colon cancer.

Methods

We selected 142 consecutive patients with high-risk stage III colon cancer who received colon tumor resection followed by modified XELOX or standard full-cycle XELOX chemotherapy from November 2007 to June 2016 at Sun Yat-sen University Cancer Center. Disease-free survival (DFS), overall survival (OS), and adverse events of patients treated with the two chemotherapy regimens were compared.

Results

Seventy-four (52.1%) patients received standard XELOX chemotherapy, and 68 (47.8%) received modified XELOX chemotherapy. Neurotoxicity was the most common adverse event in 99 (69.7%) patients. Grade 2-3 neurotoxicity, grade 2–4 thrombocytopenia and grade 3–4 leucopenia were the major severe adverse events related to the decision to treat patients with modified XELOX chemotherapy. After a median follow-up of 69 months, the modified XELOX group presented a comparable 5-year DFS rate (79.0 vs. 80.3%, P = 0.891) and 5-year OS rate (93.8 vs. 87.8%, P = 0.446) as those in the standard XELOX group. Univariate survival analysis indicated that poor tumor differentiation (HR: 2.381, 95% CI: 1.141–4.968, P = 0.021) was the only significant risk factor for DFS, but no significant prognostic factor was identified for OS.

Conclusions

The modified XELOX adjuvant chemotherapy presented a comparable oncologic efficacy as standard XELOX chemotherapy for high-risk stage III colon cancer. The modified XELOX adjuvant chemotherapy could be an alternative treatment for patients suffering severe adverse events, especially severe neurotoxicity.

Impact of Anatomic Extent of Nodal Metastasis on Adjuvant Chemotherapy Outcomes in Stage III Colon Cancer

BACKGROUND

An oxaliplatin-based chemotherapy regimen improves the survival outcomes of patients with stage III colon cancer. However, its complications are well-known.

OBJECTIVE

The purpose of this study was to distinguish between the survival outcomes of patients who underwent curative resection for stage III colon cancer with oxaliplatin chemotherapy and those who underwent such resection without oxaliplatin chemotherapy.

DESIGN

This was a retrospective analytical study based on prospectively collected data.

SETTINGS

This study used data on patients who underwent surgery at our hospital between January 2010 and December 2014.

PATIENTS

A cohort of 254 consecutive patients who underwent curative resection for stage III colon cancer was included in this study. The patients were divided into 2 groups: patients with isolated pericolic lymph node metastasis (n = 175) and those with extrapericolic lymph node metastasis (n = 79).

MAIN OUTCOME MEASURES

Clinicopathologic features and 3-year survival outcomes were analyzed with and without oxaliplatin therapy in the pericolic lymph node group.

RESULTS

The pericolic lymph node group showed significantly improved overall survival compared with the extrapericolic lymph node group at a median follow-up of 48.5 months (95.8% vs 77.8%; p < 0.001). In contrast, there was no significant difference in overall survival (99.0% vs 92.0%; p = 0.137) and disease-free survival (89.1% vs 88.2%; p = 0.460) between the oxaliplatin and nonoxaliplatin subgroups of the pericolic lymph node group. Multivariate analysis showed that the administration of oxaliplatin chemotherapy to the pericolic lymph node group did not lead to a significant difference in the overall survival (p = 0.594).

LIMITATIONS

The study was limited by its retrospective design and single institutional data analysis.

CONCLUSIONS

This study suggests that the anatomic extent of metastatic lymph nodes could affect patient prognosis, and the effect of oxaliplatin-based adjuvant chemotherapy may not be prominent in stage III colon cancer with isolated pericolic lymph node metastasis.

Colorectal cancer under 20 years old: a retrospective analysis from three tertiary hospitals

PURPOSE

Colorectal cancer (CRC) rarely occurs in children and adolescents. This study aimed to perform a retrospective analysis and disclose more detailed information about CRC in patients under 20 years old.

METHODS

Medical records of CRCs in patients under 20 years old referred to three tertiary hospitals in China from September 2000 to July 2019 were retrospectively reviewed. Clinicopathological characteristics, treatment processes and laboratory findings were summarized and treatment outcomes and prognostic factors were analyzed.

RESULTS

A total of 33,394 CRC medical records were analyzed, and we identified seventy (0.21%) CRCs in patients under 20. The most common primary tumor location was the left hemicolon (35.7%). The prominent pathological types were mucinous adenocarcinoma (22.9%) and signet ring cell carcinoma (22.9%). Nearly half (47.1%) of the patients presented with distant metastasis at diagnosis. The fractions of patients with deficient mismatch repair (dMMR) protein expression and microsatellite instability-high (MSI-H) were 23.8% (5/21) and 71.4% (5/7), respectively. Forty-four patients underwent radical surgery. Fifty-five patients received chemotherapy and six patients received radiotherapy. One dMMR/MSI-H rectal cancer patient received immunotherapy and achieved a clinically complete response. The median overall survival (OS) time was 80 months. The 3-year and 5-year OS rates were 61.8% and 57.2%, respectively. An absence of distant metastasis was a favorable factor for OS. For stage II/III CRCs, classic adenocarcinoma and radical surgery were favorable factors for OS. For stage IV CRCs, primary location at the colon was a favorable factor for OS.

CONCLUSION

Child and adolescent CRC patients are likely to have distant metastasis, undifferentiated, left hemicolon location, and a dMMR/MSI-H phenotype at diagnosis. Additional efforts are needed to improve their survival outcomes.

Development and validation of a five-lncRNA signature with prognostic value in colon cancer

Dysregulation of long noncoding RNAs (lncRNAs) has been found in a large number of human cancers, including colon cancer. Therefore, the implementation of potential lncRNAs biomarkers with prognostic prediction value are very much essential. GSE39582 data set was downloaded from database of Gene Expression Omnibus. Re-annotation analysis of lncRNA expression profiles was performed by NetAffx annotation files. Univariate and multivariate Cox proportional analyses helped select prognostic lncRNAs. Algorithm of random survival forest-variable hunting (RSF-VH) together with stepwise multivariate Cox proportional analysis were performed to establish lncRNA signature. The log-rank test was carried out to analyze and compare the Kaplan-Meier survival curves of patients' overall survival (OS). Receiver operating characteristic (ROC) analysis was used for comparing the survival prediction regarding its specificity and sensitivity based on lncRNA risk score, followed by calculating the values of area under the curve (AUC). The single-sample GSEA (ssGSEA) analysis was used to describe biological functions associated with this signature. Finally, to determine the robustness of this model, we used the validation sets including GSE17536 and The Cancer Genome Atlas data set. After re-annotation analysis of lncRNAs, a total of 14 lncRNA probes were obtained by univariate and multivariate Cox proportional analysis. Then, the RSF-VH algorithm and stepwise multivariate Cox analysis helped to build a five-lncRNA prognostic signature for colon cancer. The patients in group with high risk showed an obviously shorter survival time compared with patients in group with low risk with AUC of 0.75. In addition, the five-lncRNA signature can be used to independently predict the survival of patients with colon cancer. The ssGSEA analysis revealed that pathways such as extracellular matrix-receptor interaction was activated with an increase in risk score. These findings determined the strong power of prognostic prediction value of this five-lncRNA signature for colon cancer.

Prognostic and Predictive Molecular Biomarkers for Colorectal Cancer: Updates and Challenges

Colorectal cancer (CRC) is a leading cause of death among cancer patients. This heterogeneous disease is characterized by alterations in multiple molecular pathways throughout its development. Mutations in RAS, along with the mismatch repair gene deficiency, are currently routinely tested in clinics. Such biomarkers provide information for patient risk stratification and for the choice of the best treatment options. Nevertheless, reliable and powerful prognostic markers that can identify “high-risk” CRC patients, who might benefit from adjuvant chemotherapy, in early stages, are currently missing. To bridge this gap, genomic information has increasingly gained interest as a potential method for determining the risk of recurrence. However, due to several limitations of gene-based signatures, these have not yet been clinically implemented. In this review, we describe the different molecular markers in clinical use for CRC, highlight new markers that might become indispensable over the next years, discuss recently developed gene expression-based tests and highlight the challenges in biomarker research.

Expression of EEF1A1 Is Associated with Prognosis of Patients with Colon Adenocarcinoma

Background: The prognostic role of the translational factor, elongation factor-1 alpha 1 (EEF1A1), in colon cancer is unclear. Objectives: The present study aimed to investigate the expression of EEF1A in tissues obtained from patients with stage II and III colon cancer and analyze its association with patient prognosis. Methods: A total of 281 patients with colon cancer who underwent curative resection were analyzed according to EEF1A1 expression. Results: The five-year overall survival in the high-EEF1A1 group was 87.7%, whereas it was 65.6% in the low-EEF1A1 expression group (hazard ratio (HR) 2.47, 95% confidence interval (CI) 1.38–4.44, p = 0.002). The five-year disease-free survival of patients with high EEF1A1 expression was 82.5%, which was longer than the rate of 55.4% observed for patients with low EEF1A1 expression (HR 2.94, 95% CI 1.72–5.04, p < 0.001). Univariate Cox regression analysis indicated that age, preoperative carcinoembryonic antigen level, adjuvant treatment, total number of metastatic lymph nodes, and EEF1A1 expression level were significant prognostic factors for death. In multivariate analysis, expression of EEF1A1 was an independent prognostic factor associated with death (HR 3.01, 95% CI 1.636–5.543, p < 0.001). EEF1A1 expression was also an independent prognostic factor for disease-free survival in multivariate analysis (HR 2.54, 95% CI 1.459–4.434, p < 0.001). Conclusions: Our study demonstrated that high expression of EEF1A1 has a favorable prognostic effect on patients with colon adenocarcinoma.

DNA repair capacity and response to treatment of colon cancer

DNA repair, a complex biological process, ensures genomic integrity. Alterations in DNA repair, occurring in many cancers, contribute to the accumulation of mutations in the genome, resulting in genomic instability and cancer progression. DNA repair also plays a substantial role in response to chemotherapeutics: rapidly dividing colon cancer cells, vulnerable to DNA-damaging agents and overcoming DNA repair, undergo cell death. DNA repair capacity represents a complex biomarker, integrating gene variants, gene expressions, the stability of gene products, the effect of inhibitors/stimulators, lifestyle and environmental factors. Here, we discuss DNA repair capacity in sporadic colon cancer, a frequent malignancy worldwide, in relation to tumor heterogeneity, prognosis and prediction, measurements in surrogate and target tissues and suggest important tasks to be addressed.

Safety and efficacy of a modified XELOX adjuvant regimen for patients with operated stage III colon cancer: a Chinese single-center experience

Background

A fixed 8-cycle oxaliplatin and capecitabine (XELOX) regimen has been the standard adjuvant therapy for patients with stage III colon cancer. However, completing the full-cycle of oxaliplatin is often associated with severe neurotoxicity. To spare patients from the toxic effects, without comprising the required efficacy, we evaluated the safety and efficacy of a modified XELOX (mXELOX) adjuvant chemotherapy regimen with 6 cycles of oxaliplatin and a full cycle of capecitabine.

Methods

We retrospectively analyzed 330 eligible patients with stage III colon cancer who underwent curative tumor resection followed by mXELOX, standard XELOX or unfinished XELOX adjuvant chemotherapy between December 2007 and April 2015. Associated prognostic factors were investigated and their disease-free survival (DFS) and overall survival (OS) rates were also determined and compared among the different regimen groups.

Results

Compared with the standard XELOX group, the mXELOX group had lower total incidence rates of neurotoxicity (39.3% vs. 76.2%, P < 0.001), leucopenia (53.6% vs. 69.8%, P = 0.017) and thrombocytopenia (38.1% vs. 56.3%, P = 0.011). The standard XELOX and mXELOX adjuvant chemotherapy regimens presented with comparable 3-year DFS rates (86.3% vs. 89.2%; P = 0.838) and 3-year OS rates (92.7% vs. 97.6%; P = 0.227). Compared to unfinished XELOX chemotherapy, the oncologic benefits of the mXELOX regimen were greater for patients with T4 tumors (3-year DFS: Hazard ratio [HR], 2.184; 95% confidence interval [CI], 1.051–4.540; P = 0.036; 3-year OS: HR, 4.529; 95% CI 1.245–16.479; P = 0.022) and for high-risk patients (3-year DFS: HR, 1.962; 95% CI 0.964–3.993; P = 0.044; 3-year OS: HR, 4.193; 95% CI 1.182–14.874; P = 0.026).

Conclusions

The mXELOX adjuvant chemotherapy presented a comparable survival benefit and lower incidence of toxicity than standard XELOX chemotherapy. It could be an alternative treatment for high-risk patients with operated stage III colon cancer.

IRAK4 mediates colitis-induced tumorigenesis and chemoresistance in colorectal cancer

Aberrant activation of the NF-κB transcription factors underlies chemoresistance in various cancer types, including colorectal cancer (CRC). Targeting the activating mechanisms, particularly with inhibitors to the upstream IκB kinase (IKK) complex, is a promising strategy to augment the effect of chemotherapy. However, clinical success has been limited, largely because of low specificity and toxicities of tested compounds. In solid cancers, the IKKs are driven predominantly by the Toll-like receptor (TLR)/IL-1 receptor family members, which signal through the IL-1 receptor-associated kinases (IRAKs), with isoform 4 (IRAK4) being the most critical. The pathogenic role and therapeutic value of IRAK4 in CRC have not been investigated. We found that IRAK4 inhibition significantly abrogates colitis-induced neoplasm in APCMin/+ mice, and bone marrow transplant experiments showed an essential role of IRAK4 in immune cells during neoplastic progression. Chemotherapy significantly enhances IRAK4 and NF-κB activity in CRC cells through upregulating TLR9 expression, which can in turn be suppressed by IRAK4 and IKK inhibitors, suggesting a feed-forward pathway that protects CRC cells from chemotherapy. Lastly, increased tumor phospho-IRAK4 staining or IRAK4 mRNA expression is associated with significantly worse survival in CRC patients. Our results support targeting IRAK4 to improve the effects of chemotherapy and outcomes in CRC.

Identification and Validation of Tumor Stromal Immunotype in Patients With Hepatocellular Carcinoma

Background: The immune landscape of hepatocellular carcinoma (HCC) is heterogeneous. This study aims to develop the immune type which could improve predictive value of HCC survival. Methods: A total of 208 HCC patients in the testing cohort, 112 patients in the validation cohort and 365 HCC patients in the TCGA database were included in this study. Immune features were assessed by immunohistochemical staining or CIBERSORT method. We constructed prognostic classifiers by LASSO COX analyses in the TCGA cohort, which identified five features out of the 22 types of immune cells. Results: The formulas based on the immunohistochemical staining are as follows: IS_OS = 0.648^* Macrophage_stromal + 0.444^*Neutrophils_stromal + 0.218^*Tregs_stromal - 0.703^*Memory T cells_stromal; IS_DFS = 0.285^*B cells_stromal + 0.494^*Neutrophils_stromal + 0.431^*Tregs_stromal - 0.736^*Memory T cells_stromal. We classified HCC patients into immune type A subgroup (IS-A) and type B subgroup (IS-B) based on immune scores. The immune type was an independent prognostic indicator for disease-free survival (DFS) and overall survival (OS) in both testing and validation cohorts. Two nomograms (for OS and DFS) that integrated the immune type and clinicopathologic risk factors also showed good predictive accuracy and discriminatory power. IS-A group was correlated with higher immune checkpoint molecule expression. In addition, patients with IS-A and IS-B had distinct mutation signature. Conclusion: The immune types could predict survival and recurrence of HCC effectively. In addition, the immunosuppressive pathways and mutation signature are distinct between two immune types.

Study of the antitumor mechanisms of apiole derivatives (AP-02) from Petroselinum crispum through induction of G0/G1 phase cell cycle arrest in human COLO 205 cancer cells

Background

Apiole was isolated from the leaves of various plants and vegetables and has been demonstrated to inhibit human colon cancer cell (COLO 205 cells) growth through induction of G0/G1 cell cycle arrest and apoptotic cell death. This study further explored the antitumor effects of apiole derivatives AP-02, 04, and 05 in COLO 205 cancer cells.

Methods

Human breast (MDA-MB-231, ZR75), lung (A549, PE089), colon (COLO 205, HT 29), and hepatocellular (Hep G2, Hep 3B) cancer cells were treated with apiole and its derivatives in a dose-dependent manner. Flow cytometry analysis was subsequently performed to determine the mechanism of AP-02-induced G0/G1 cell cycle arrest. The in vivo antitumor effect of AP-02 (1 and 5 mg/kg, administered twice per week) was examined by treating athymic nude mice bearing COLO 205 tumor xenografts. The molecular mechanisms of AP-02-induced antitumor effects were determined using western blot analysis.

Results

AP-02 was the most effective compound, especially for inhibition of COLO 205 colon cancer cell growth. The cytotoxicity of AP-02 in normal colon epithelial (FHC) cells was significantly lower than that in other normal cells derived from the breast, lung or liver. Flow cytometry analysis indicated that AP-02-induced G0/G1 cell cycle arrest in COLO 205 cells but not in HT 29 cells (< 5 μM for 24 h, **p < 0.01). Tumor growth volume was also significantly inhibited in AP-02 (> 1 mg/kg)-treated athymic nude mice bearing COLO 205 tumor xenografts compared to control mice (*p < 0.05). Furthermore, G0/G1 phase regulatory proteins (p53 and p21/Cip1) and an invasion suppressor protein (E-cadherin) were significantly upregulated, while cyclin D1 was significantly downregulated, in AP-02-treated tumor tissues compared to the control group (> 1 mg/kg, *p < 0.05).

Conclusions

Our results provide in vitro and in vivo molecular evidence of AP-02-induced anti-proliferative effects on colon cancer, indicating that this compound might have potential clinical applications.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2590-9) contains supplementary material, which is available to authorized users.

TYMS/KRAS/BRAF molecular profiling predicts survival following adjuvant chemotherapy in colorectal cancer

BACKGROUND

Patients with stage II-III colorectal cancer (CRC) treated with adjuvant chemotherapy, gain a 25% survival benefit. In the context of personalized medicine, there is a need to identify patients with CRC who may benefit from adjuvant chemotherapy. Molecular profiling could guide treatment decisions in these patients. Thymidylate synthase (TYMS) gene polymorphisms, KRAS and BRAF could be included in the molecular profile under consideration.

AIM

To investigate the association of TYMS gene polymorphisms, KRAS and BRAF mutations with survival of CRC patients treated with chemotherapy.

METHODS

A retrospective study studied formalin-fixed paraffin-embedded tissues (FFPEs) of consecutive patients treated with adjuvant chemotherapy during January/2005-January/2007. FFPEs were analysed with PCR for the detection of TYMS polymorphisms, mutated KRAS (mKRAS) and BRAF (mBRAF). Patients were classified into three groups (high, medium and low risk) according to 5’UTR TYMS polymorphisms Similarly, based on 3’UTR polymorphism ins/loss of heterozygosity (LOH) patients were allocated into two groups (high and low risk of relapse, respectively). Cox regression models examined the associated 5-year survival outcomes.

RESULTS

One hundred and thirty patients with early stage CRC (stage I-II: 55 patients; stage III 75 patients; colon: 70 patients; rectal: 60 patients) were treated with surgery and chemotherapy. The 5-year disease free survival and overall survival rate was 61.6% and 73.9% respectively. 5’UTR polymorphisms of intermediate TYMS polymorphisms (2RG/3RG, 2RG/LOH, 3RC/LOH) were associated with lower risk for relapse [hazard ratio (HR) 0.320, P = 0.02 and HR 0.343, P = 0.013 respectively] and death (HR 0.368, P = 0.031 and HR 0.394, P = 0.029 respectively). The 3’UTR polymorphism ins/LOH was independently associated with increased risk for disease recurrence (P = 0.001) and death (P = 0.005). mBRAF (3.8% of patients) was associated with increased risk of death (HR 4.500, P = 0.022) whereas mKRAS (39% of patients) not.

CONCLUSION

Prospective validating studies are required to confirm whether 2RG/3RG, 2RG/LOH, 3RC/LOH, absence of ins/LOH and wild type BRAF may indicate patients at lower risk of relapse following adjuvant chemotherapy.

External validation of molecular subtype classifications of colorectal cancer based on microsatellite instability, CIMP, BRAF and KRAS

Background

Competing molecular classification systems have been proposed to complement the TNM staging system for a better prediction of survival in colorectal cancer (CRC). However, validation studies are so far lacking. The aim of this study was to validate and extend previously published molecular classifications of CRC in a large independent cohort of CRC patients.

Methods

CRC patients were recruited into a population-based cohort study (DACHS). Molecular subtypes were categorized based on three previously published classifications. Cox-proportional hazard models, based on the same set of patients and using the same confounders as reported by the original studies, were used to determine overall, cancer-specific, or relapse-free survival for each subtype. Hazard ratios and confidence intervals, as well as Kaplan-Meier plots were compared to those reported by the original studies.

Results

We observed similar patterns of worse survival for the microsatellite stable (MSS)/BRAF-mutated and MSS/KRAS-mutated subtypes in our validation analyses, which were included in two of the validated classifications. Of the two MSI subtypes, one defined by additional presence of CIMP-high and BRAF-mutation and the other by tumors negative for CIMP, BRAF and KRAS-mutations, we could not confirm associations with better prognosis as suggested by one of the classifications. For two of the published classifications, we were able to provide results for additional subgroups not included in the original studies (men, other disease stages, other locations).

Conclusions

External validation of three previously proposed classifications confirmed findings of worse survival for CRC patients with MSS subtypes and BRAF or KRAS mutations. Regarding MSI subtypes, other patient characteristics such as stage of the tumor, may influence the potential survival benefit. Further integration of methylation, genetic, and immunological information is needed to develop and validate a comprehensive classification that will have relevance for use in clinical practice.

Colorectal cancer mutations are associated with survival and recurrence after pulmonary metastasectomy

BACKGROUND AND OBJECTIVES

While knowledge has grown extensively regarding the impact of mutations on colorectal cancer prognosis, their role in outcomes after pulmonary metastasectomy (PM) remains minimally understood. We sought to determine the prognostic role of mutant disease on survival and recurrence after metastasectomy.

METHODS

Patients with available tumor sequencing profiles who underwent PM for colorectal cancer at a single institution from 2011 to 2017 were reviewed. Various demographic and clinicopathologic factors, as well as mutational status, were tested in the Cox regression analyses to identify predictors of survival and disease-free survival (DFS).

RESULTS

A total of 130 patients met inclusion criteria, among whom 78 (60%) were male and the mean age was 57 years. The median survival time and 5-year survival rate were 58.2 months and 47%, respectively. A single pulmonary nodule was present in 54%. Disease recurrence occurred for 87 (67%) patients, including 75 (58%) who had at least one lung recurrence after metastasectomy at a median time to recurrence of 19.4 months. Upon multivariable analysis, RAS and TP53 mutations were associated with shorter survival DFS, while APC is associated with prolonged survival.

CONCLUSIONS

After metastasectomy for colorectal cancer, mutations in RAS, TP53, and APC play an important role in survival and recurrence.

Influence of Molecular Status on Recurrence Site in Patients Treated for a Stage III Colon Cancer: a Post Hoc Analysis of the PETACC-8 Trial

BACKGROUND

Recurrence patterns in stage III colon cancer (CC) patients according to molecular markers remain unclear. The objective of the study was to assess recurrence patterns according to microsatellite instability (MSI), RAS and BRAF^V600E status in stage III CC patients.

METHODS

All stage III CC patients from the PETACC-8 randomized trial tested for MSI, RAS and BRAF^V600E status were included. The site and characteristics of recurrence were analyzed according to molecular status. Survival after recurrence (SAR) was analyzed.

RESULTS

A total of 1650 patients were included. Recurrence occurred in 434 patients (26.3%). Microsatellite stable (MSS) patients had a significantly higher recurrence rate (27.2% vs. 18.7%, P = 0.02) with a trend to more pulmonary recurrence (28.8% vs. 12.9%, P = 0.06) when compared to MSI patients. MSI patients experienced more regional lymph nodes compared to MSS (12.9% vs. 4%, P = 0.046). In the MSS population, the recurrence rate was significantly higher in RAS (32.2%) or BRAF (32.3%) patients when compared to double wild-type patients (19.9%) (p < 0.001); no preferential site of recurrence was observed according to RAS and BRAF^V600E mutations. Finally, decreased SAR was observed in the case of peritoneal recurrence or more than two recurrence sites.

CONCLUSIONS

Microsatellite, RAS and BRAF^V600E status influences recurrence rates in stage III CC patients. However, only microsatellite status seems to be associated with specific recurrence patterns. More than two recurrence sites and recurrence in the peritoneum were associated with poorer SAR.

RNA sequencing reveals PNN and KCNQ1OT1 as predictive biomarkers of clinical outcome in stage III colorectal cancer patients treated with adjuvant chemotherapy

Five-year overall survival of stage III colorectal cancer (CRC) patients treated with standard adjuvant chemotherapy (ACHT) is highly variable. Genomic biomarkers and/or transcriptomic profiles identified lack of adequate validation. Aim of our study was to identify and validate molecular biomarkers predictive of ACHT response in stage III CRC patients by a transcriptomic approach. From a series of CRC patients who received ACHT, two stage III extreme cohorts (unfavorable vs. favorable prognosis) were selected. RNA-sequencing was performed from fresh frozen explants. Tumors were characterized for somatic mutations. Validation was performed in stage III CRC patients extracted from two GEO datasets. According to disease-free survival (DFS), 108 differentially expressed genes (104/4 up/downregulated in the unfavorable prognosis group) were identified. Among 104 upregulated genes, 42 belonged to olfactory signaling pathways, 62 were classified as pseudogenes (n = 17), uncharacterized noncoding RNA (n = 10), immune response genes (n = 4), microRNA (n = 1), cancer-related genes (n = 14) and cancer-unrelated genes (n = 16). Three out of four down-regulated genes were cancer-related. Mutational status (i.e., RAS, BRAF, PIK3CA) did not differ among the cohorts. In the validation cohort, multivariate analysis showed high PNN and KCNQ1OT1 expression predictive of shorter DFS in ACHT treated patients (p = 0.018 and p = 0.014, respectively); no difference was observed in untreated patients. This is the first study that identifies by a transcriptomic approach and validates PNN and KCNQ1OT1 as molecular biomarkers predictive of chemotherapy response in stage III CRC patients. After a further validation in an independent cohort, PNN and KCNQ1OT1 evaluation could be proposed to prospectively identify stage III CRC patients benefiting from ACHT.

Right-sided vs. left-sided obstructing colonic cancer: results of a multicenter study of the French Surgical Association in 2325 patients and literature review

PURPOSE

Few studies compared management and outcomes of obstructing colonic cancer (OCC), according to the tumor site. Our aim was to compare patient and tumor characteristics, postoperative and pathological results, and oncological outcomes after emergency management of right-sided vs. left-sided OCC.

METHODS

A national cohort study including all consecutive patients managed for OCC from 2000 to 2015 in French surgical centers members of the French National Surgical Association (AFC).

RESULTS

During the study period, 2325 patients with OCC were divided in right-sided (n = 819, 35%) and left-sided (n = 1506, 65%) locations. Patients with right-sided OCC were older, more frequently females, and associated with comorbidities, history of cancer, or previous laparotomy. Surgical management was more frequently performed for right-sided than left-sided OCC (99 vs. 96%, p < 0.0001). Tumor resection was more frequently performed in right-sided OCC (95 vs. 90%, p < 0.0001). Among the resected patients, primary anastomosis was more frequently performed in case of right-sided OCC (86 vs. 62%, p < 0.0001). Definitive stoma rate was lower in right-sided location (17 vs. 46%, p < 0.0001). There was no significant difference between locations in terms of cumulative morbidity, anastomotic leak, unplanned reoperation, and mortality. Five-year overall and disease-free survival rates were significantly lower in right-sided OCC (43 and 36%) than in left-sided OCC (53 and 46%, p < 0.0001 and p = 0.001, respectively).

CONCLUSIONS

Although patients with right-sided OCC are frailer than left-sided OCC, tumor resection and anastomosis are more frequently performed, without difference in surgical results. However, right-sided OCC is associated with worse prognosis than distal location.

Associations Between Molecular Classifications of Colorectal Cancer and Patient Survival: A Systematic Review

BACKGROUND & AIMS

Colorectal cancer (CRC) is a heterogeneous disease with different mechanisms of pathogenesis. Classification systems have been proposed based on molecular features of tumors, but none are used in clinical practice. We performed a systematic review of studies on the associations between molecular classifications of CRC and patient survival.

METHODS

We searched the PubMed, Embase, Cochrane, and Web of Science databases for combinations of terms related to CRC, molecular markers, subtype classifications, and survival (overall survival, disease-specific survival, disease-free survival). We included only studies that used at least 3 molecular markers to classify tumors and provided an estimate of survival associated with each subtype. Data extraction and quality assessment were performed independently by 2 reviewers.

RESULTS

We identified 6 studies that fulfilled the inclusion criteria. In these studies, molecular subtypes were assigned based on pathways associated with tumor development or findings from gene expression clustering analyses. Most studies proposed classification systems with 5 subtypes, including information on microsatellite instability, mutations in BRAF, and mutations in KRAS. None of the studies included TNM stage in their classification system. Three classification systems used similar definitions. Only 3 studies provided internal or external validation of the proposed classification schemes. Tumors with microsatellite stability and mutations in KRAS or BRAF were associated with decreased survival times, compared with tumors with microsatellite stability and no mutations.

CONCLUSIONS

In a systematic review of studies of molecular classifications of CRC and patient survival, we found that most subtypes were not significantly or not differentially associated with survival. None of the systems integrated TNM staging. Further research and validation are needed to develop molecular subtype classification systems for clinical practice.

Colorectal Cancer: Why Does Side Matter?

Colorectal cancer (CRC) is a heterogeneous disease, and the search for clinical and molecular prognostic and predictive factors is thus necessary to better tailor each individual patient's management. Primary tumor location (PTL) seems to act as a master prognostic factor pooling different clinical, pathological, and molecular poor prognostic factors. In fact, right-sided (RS) CRC patients are more frequently female and elderly with microsatellite unstable, BRAF mutated, CpG island methylator phenotype (CIMP)-high, poorly differentiated tumors, compared to left-sided (LS) CRC patients. PTL does not seem to clearly influence disease-free survival (DFS) in localised colon cancer even though the opposite prognostic value of RS tumors on DFS depending on RAS/BRAF mutational status has been recently suggested in these patients. In metastatic CRC (mCRC), the poor prognosis associated with RS tumors is confirmed in the most recent publications in the era of double and triple chemotherapeutic regimens and targeted agents. Concerning the predictive value of PTL, in patients with RAS wild-type mCRC in the first-line setting, anti-epidermal growth factor receptor (EGFR) therapy combined with chemotherapy appears to be more effective than bevacizumab in LS CRC, while patients with RS CRC benefit less from anti-EGFR therapy, and intensive chemotherapy plus bevacizumab may be more appropriate but EGFR antibodies remain an option if objective response is needed. Due to the limitation of the current data (unplanned and retrospective analyses), these conclusions must be interpreted with caution. Clinical trials in RS CRC may be of interest to clarify what is the best treatment strategy in these patients.

RAS genes in colorectal carcinoma: pathogenesis, testing guidelines and treatment implications

The RAS family is among the most commonly mutated genes in all human malignancies including colon cancer. In normal cells, RAS proteins act as a link in the intracellular signal transduction initiated by binding of growth factors to cell membrane receptors mediating cell survival. RAS isoproteins have great morphological similarities, but despite that, they are thought to have different functions in different tissues. RAS mutations, as supported by several studies including animal models, have a role in the development and progression of colorectal cancer. The detection of RAS mutations in patients with colorectal carcinoma, specifically KRAS and NRAS, has significant clinical implications. It is currently recommended that patients with colon cancer who are considered for antiepidermal growth factor receptor monoclonal antibodies, get RAS mutation testing since only those with wildtype-RAS genes benefit from such treatment. Despite decades of research, there is currently no effective and safe treatment that directly targets RAS-mutated neoplasms. Multiple therapeutic approaches directed against RAS mutations are currently experimental, including a promising immunotherapy study using T-cells in patients with metastatic colon cancer.

Base excision repair capacity as a determinant of prognosis and therapy response in colon cancer patients

The DNA-damaging agent 5-fluorouracil represents the most commonly used chemotherapeutic drug for colorectal cancer patients. DNA lesions associated with 5-fluorouracil therapy are primarily repaired by base excision repair (BER) and mismatch repair (MMR) pathways. Published evidence suggests that the individual DNA repair capacity (DRC) may affect a patient's prognosis and response to chemotherapy. With this in mind, we designed a prospective study of which the main aim was to investigate BER-DRC in relation to 5-fluorouracil response as potential predictive and/or prognostic biomarker. BER-DRC was supplemented by a microsatellite instability (MSI) analysis which represents an indirect marker of MMR activity in the tumor. All parameters were measured in paired samples of tumor tissue and non-malignant adjacent mucosa of 123 incident colon cancer patients. Our results indicate that BER-DRC in non-malignant adjacent mucosa was positively associated with overall survival (P = 0.007) and relapse-free survival (P = 0.04). Additionally, in multivariate analysis, good therapy responders in TNM stage II and III with an elevated BER-DRC in mucosa exhibited better overall survival. Moreover, the overall survival of these patients was even better in the presence of a decreased BER-DRC in tumor tissue. The ratio of BER-DRC in tumor tissue over BER-DRC in mucosa positively correlated with advanced tumor stage (P = 0.003). With respect to MSI, we observed that MSI-high tumors were mostly localized in proximal colon; however, in our cohort, the MSI status affected neither patients' prognosis nor survival. In summary, the results of the present study suggest that the level of BER-DRC is associated with patients' survival. BER-DRC represents a potential prognostic biomarker, applicable for prediction of therapy response and useful for individual approach to patients.

[How to predict the relapse after surgery or radiofrequency of liver metastases of colorectal cancer? Interest of the serum kinetic variation of a matrix metalloproteinase cluster]

INTRODUCTION

Recurrence after liver surgery or radiofrequency is a clinical and biological challenge because it worsens the colorectal cancer prognosis. To date, no biomarker is yet validated to predict the recurrence in order to intensify adjuvant therapy for patients with higher risk. Matrix metalloproteinases play a major role in the metastasis dissemination and tumoral microenvironment and could be a potential biomarker of interest.

METHODS

Forty-four patients with liver metastasis treated by surgery or radiofrequency were enrolled in this study. Serum levels of MMP-1, MMP-2, MMP-7, MMP-9 and TIMP-1 were monitored in Elisa after therapy and correlated to the recurrence from January 2004 to December 2007. After the curative treatment, patients were assessed for the recurence for two years by CT-scan and examination.

RESULTS

Post-operative serum level of MMP-9 was significantly higher between J0, J1 and J45 after liver surgery or radiofrequency (***P≤0.001). Level of MMP-2 was significantly increased at M3 and M6 (***P≤0.001) but does not appear to be a risk factor of liver recurrence. The level of TIMP-1 at J0 is a deleterious factor (HR=1.76, P=0.042*).

CONCLUSION

This is the first study wich correlates the post-operative level of 4 MMPs and TIMP-1 with the risk of liver recurrence after surgery or radiofrequency. Serum TIMP-1 level at J0 could be helpful to identify patients with higher risk but these results need to be confirmed in a large-scale study.

Adjuvant Therapy for Colon Cancer: Genes, Genes… and the Patient in the Center

Although molecular subtype-based stratification and genomic signatures of increasing complexity are becoming a new strategy to guide therapeutic decisions in stage II/III colon cancer, several prognostic factors that can be easily obtained from formalin-fixed paraffin-embedded (FFPE) specimens should be considered to create combined models that better define individual patients' needs. Clin Cancer Res; 24(16); 3787-9. ©2018 AACRSee related article by Kandimalla et al., p. 3867.

Noninferiority of three months versus six months of oxaliplatin-based adjuvant chemotherapy for resected colon cancer. How should IDEA findings affect clinical practice?

The eagerly awaited results of the multi-continental International Duration Evaluation of Adjuvant Chemotherapy (IDEA) project have recently been presented at major oncological meetings. The 3-year disease-free survival (DFS) was presented for 12,834 Stage III colon cancer patients in a pooled analysis of 6 individual noninferiority phase III randomized trials, all investigating three versus six months of oxaliplatin-based adjuvant therapy. Noninferiority (NI) could not be demonstrated for the whole population as the DFS hazard ratio (HR) of 1.07 with its 95% CI of 1.00-1.15 crossed the postulated NI boundary of 1.12. However, there was an expected reduction in the incidence of specific side effects with the three months treatment. NI could be demonstrated for the T3N1 subgroup (∼60% of patients, HR for DFS 1.01, 95% CI 0.90-1.12). Moreover, NI was also declared for the subgroup treated with the CAPOX regimen (capecitabine plus oxaliplatin, ∼40% of patients), but the CAPOX choice was physician-based and not subject to randomization. Overall, the IDEA results indicate that three months of therapy might be adequate for most of Stage III tumors; however, a small subset of these patients still have high risk of recurrence and death with short treatment duration. Precise predictors of benefit need to be identified, nonetheless tumor-intrinsic factors, such as tumor stage, might currently be considered as useful tools to inform the decision-making process.

Real-World Implications of Nonbiological Factors with Staging, Prognosis and Clinical Management in Colon Cancer

Background: The present study analyzed the nonbiological factors (NBFs) together with the American Joint Committee on Cancer (AJCC) Tumor-Node-Metastasis (TNM) staging system to generate a refined, risk-adapted stage for the clinical treatment of colon cancer. Methods: Eligible patients (N = 28,818) with colon cancer between 1 January 2010 and 31 December 2014, were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier curves and Cox proportional hazards regression, analyzed the probabilities of cancer-specific survival (CSS) in patients with colon cancer, with different NBF-TNM stages. Results: Insurance status, marital status, and median household income were significant prognostic NBFs in the current study (p < 0.05). The concordance index of NBF-TNM stage was 0.857 (95% confidence interval (CI) = 0.8472⁻0.8668). Multivariate Cox analyses, indicated that NBF1-stage was independently associated with a 50.4% increased risk of cancer-specific mortality in colon cancer (p < 0.001), which increased to 77.1% in non-metastatic colon cancer. NBF0-stage improved in CSS as compared to the NBF1-stage in the respective stages (p < 0.05). Conclusions: The new proposed NBF-stage was an independent prognostic factor in colon cancer. Effect of NBFs on the survival of colon cancer necessitates further clinical attention. Moreover, the incorporation of NBF-stage into the AJCC TNM staging system is essential for prognostic prediction, and clinical guidance of adjuvant chemotherapy in stage II and III colon cancer.

Real-world study of a novel prognostic scoring system: for a more precise prognostication and better clinical treatment guidance in stages II and III colon cancer

PURPOSE

This study aimed to improve the American Joint Committee on Cancer (AJCC) Tumor Node Metastases (TNM) staging system and demonstrate the improvement in prognostic accuracy and clinical management guidance in colon cancer using the novel prognostic score (P score).

METHODS

Eligible patients were identified using the Surveillance, Epidemiology, and End Results database. A P score (based on age, tumor size, and tumor grade) was assigned to each patient. The Cox proportional hazards regression analyses were performed to identify independent factors associated with prognosis. The Kaplan-Meier survival curves were used to analyze the prognosis of patients with colon cancer with different P scores. The TNM staging system was compared with the P score in stages I-IV by calculating the concordance index.

RESULTS

The multivariate Cox analysis indicated that a higher P score was independently associated with a higher risk of cancer-specific mortality. The Kaplan-Meier survival curves showed that the survival benefit gradually increased as the P score decreased. The concordance index rose from 0.5, 0.593, 0.633, and 0.551 of AJCC TNM staging system to 0.709, 0.651, 0.691, and 0.623 of P score in stages I-IV, respectively.

CONCLUSIONS

The P score was an independent prognostic factor of colon cancer and had a much better prognostic accuracy than the AJCC TNM staging system in all patients with colon cancer. It may help in identifying patients with high-risk stage II colon cancer who were candidates for adjuvant therapy and differentiating patients with stage III colon cancer for adjuvant therapy.