Clinicopathological and biomolecular characteristics of stage IIB/IIC and stage IIIA colon cancer: Insight into the survival paradox

Converging deep learning and human-observed tumor-adipocyte interaction as a biomarker in colorectal cancer

BACKGROUND

Tumor-Adipose-Feature (TAF) as well as SARIFA (Stroma AReactive Invasion Front Areas) are two histologic features/biomarkers linking tumor-associated adipocytes to poor outcomes in colorectal cancer (CRC) patients. Whereas TAF was identified by deep learning (DL) algorithms, SARIFA was established as a human-observed histopathologic biomarker.

METHODS

To study the overlap between TAF and SARIFA, we performed a systematic pathological review of TAF based on all published image tiles. Additionally, we analyzed the presence/absence of TAF in SARIFA-negative CRC cases to elucidate the biologic and prognostic role of a direct tumor-adipocyte contact. TCGA-CRC gene expression data is investigated to assess the association of FABP4 (fatty-acid binding protein 4) and CD36 (fatty-acid translocase) with both TAF and CRC prognosis.

RESULTS

By investigating the TAF/SARIFA overlap, we show that many TAF patches correspond to the recently described SARIFA-phenomenon. Even though there is a pronounced morphological and biological overlap, there are differences in the concepts. The presence of TAF in SARIFA-negative CRCs is not associated with poor outcomes in this cohort, potentially highlighting the importance of a direct tumor-adipocyte interaction. Upregulation of FABP4 and CD36 gene expression seem both linked to a poor prognosis in CRC.

CONCLUSIONS

By proving the substantial overlap between human-observed SARIFA and DL-based TAF as morphologic biomarkers, we demonstrate that linking DL-based image features to independently developed histopathologic biomarkers is a promising tool in the identification of clinically and biologically meaningful biomarkers. Adipocyte-tumor-cell interactions seem to be crucial in CRC, which should be considered as biomarkers for further investigations.

The Causes Behind the Survival Paradox in Non-Metastatic Colorectal Cancer Patients and its Impact on the Treatment Regimen: A Retrospective Cohort Study

BACKGROUND

The survival paradox (ie, the prognosis of the population at earlier tumor stages is worse than that of the population at later stages) has been observed in colorectal cancer based on the American Joint Committee on Cancer Tumor-Nodes-Metastases staging system. We aimed to clarify the reason for the survival paradox and its impact on patient treatment.

METHODS

We conducted a retrospective study analyzing eligible patients with colorectal cancer from the Surveillance, Epidemiology, and End Results database and Zhejiang Cancer Hospital between 2010 and 2019. Adjusting for confounders using propensity score matching allowed confirmation of the effect of staging on the survival paradox.

RESULTS

Based on the Surveillance, Epidemiology, and End Results database, the subgroups with survival paradox might be IIB/C versus IIIA, IIA versus IIIA, and T4N0 (IIB/C) versus T3N1 (IIIB). After propensity score matching, stage IIB/C still had a worse prognosis than stage IIIA (5-year overall survival: 69.3% vs 78.5%, P < .001). Interestingly, the proportion of stage IIIA people receiving chemotherapy was higher than that of stage IIB/C (P < .001), and logistic regression models showed that staging was the reason for deciding whether a patient receives chemotherapy or not. These phenomena between stage IIB/C and IIIA were verified in the local database.

CONCLUSION

These results suggested that the survival paradox was mainly due to underestimation of stage T4 weights or overestimation of stage N1 weights, and the low proportion of chemotherapy in patients with T4N0M0 colorectal cancer (proven to be more malignant than stage IIIA) might be related to the assignment to earlier stages, resulting in a lack of attention and poor compliance to chemotherapy in these patients.

Complete Obstruction, a Real Risk Factor: A Comprehensive Study on Obstruction in Stage IIA Colon Cancer With Propensity Score Matching Analysis

MICROABSTRACT

This study evaluates the prognostic significance of obstructions in stage IIA colon cancer, distinguishing between partial and complete obstructions. It employs a retrospective review of 1914 patients with propensity score matching to analyze oncologic outcomes. Findings reveal complete obstruction as a significant risk factor for poorer outcomes, emphasizing the necessity for further research to refine treatment strategies, particularly regarding the efficacy of adjuvant chemotherapy across obstruction types.

BACKGROUND

This study examined the prognostic impact of obstructions in stage IIA colon cancer. The analysis specifically differentiated partial and complete obstructions, analyzing their distinct influences of both on oncologic outcomes.

MATERIALS AND METHODS

A retrospective review was conducted of stage IIA colon cancer cases with the presence of an obstruction. Patients were stratified by whether it was partial or complete based on the severity of obstruction. Propensity score matching was employed to control for confounders.

RESULTS

Among 1914 consecutive patients diagnosed with stage IIA colon cancer, 758 patients (597 patients with partial obstruction, 161 patients with complete obstruction) exhibited obstruction, while 1156 patients had no obstruction. The median follow-up period was 126 months. Complete obstruction was associated with poorer disease-free survival (Hazard ratio (HR) = 1.785, P < .001) and overall survival (HR = 1.853, P = .001). This trend persisted after propensity score matching, patients with complete obstruction showing a worsened disease-free survival (HR = 1.666, P = .028) and overall survival (HR = 1.732, P = .041). Adjuvant chemotherapy showed improved outcomes overall, but its efficacy varied across obstruction types.

CONCLUSION

Differentiating between complete and partial obstructions in stage IIA colon cancer is an important clinical distinction, as our findings suggest that complete obstruction is a significant risk factor for poorer oncologic outcomes. While adjuvant chemotherapy generally improves prognosis in stage IIA colon cancer, the correlation of obstruction type with its efficacy remains uncertain, necessitating further research to refine treatment strategies.

Stroma AReactive Invasion Front Areas (SARIFA): a novel histopathologic biomarker in colorectal cancer patients and its association with the luminal tumour proportion

BACKGROUND

Stroma AReactive Invasion Front Areas (SARIFA) is a novel prognostic histopathologic biomarker measured at the invasive front in haematoxylin & eosin (H&E) stained colon and gastric cancer resection specimens. The aim of the current study was to validate the prognostic relevance of SARIFA-status in colorectal cancer (CRC) patients and investigate its association with the luminal proportion of tumour (PoT).

METHODS

We established the SARIFA-status in 164 CRC resection specimens. The relationship between SARIFA-status, clinicopathological characteristics, recurrence-free survival (RFS), cancer-specific survival (CSS), and PoT was investigated.

RESULTS

SARIFA-status was positive in 22.6% of all CRCs. SARIFA-positivity was related to higher pT, pN, pTNM stage and high grade of differentiation. SARIFA-positivity was associated with shorter RFS independent of known prognostic factors analysing all CRCs (RFS: hazard ratio (HR) 2.6, p = 0.032, CSS: HR 2.4, p = 0.05) and shorter RFS and CSS analysing only rectal cancers. SARIFA-positivity, which was measured at the invasive front, was associated with PoT-low (p = 0.009), e.g., higher stroma content, and lower vessel density (p = 0.0059) measured at the luminal tumour surface.

CONCLUSION

Here, we validated the relationship between SARIFA-status and prognosis in CRC patients and provided first evidence for a potential prognostic relevance in the subgroup of rectal cancer patients. Interestingly, CRCs with different SARIFA-status also showed histological differences measurable at the luminal tumour surface. Further studies to better understand the relationship between high luminal intratumoural stroma content and absence of a stroma reaction at the invasive front (SARIFA-positivity) are warranted and may inform future treatment decisions in CRC patients.

Novel biomarker SARIFA in colorectal cancer: highly prognostic, not genetically driven and histologic indicator of a distinct tumor biology

SARIFA (Stroma AReactive Invasion Front Areas) has recently emerged as a promising histopathological biomarker for colon and gastric cancer. To elucidate the underlying tumor biology, we assessed SARIFA-status in tissue specimens from The-Cancer-Genome-Atlas (TCGA) cohorts COAD (colonic adenocarcinoma) and READ (rectal adenocarcinoma). For the final analysis, 207 CRC patients could be included, consisting of 69 SARIFA-positive and 138 SARIFA-negative cases. In this external validation cohort, H&E-based SARIFA-positivity was strongly correlated with unfavorable overall, disease-specific, and progression-free survival, partly outperforming conventional prognostic factors. SARIFA-positivity was not associated with known high-risk genetic profiles, such as BRAF V600E mutations or microsatellite-stable status. Transcriptionally, SARIFA-positive CRCs exhibited an overlap with CRC consensus molecular subtypes CMS1 and CMS4, along with distinct differential gene expression patterns, linked to lipid metabolism and increased stromal cell infiltration scores (SIIS). Gene-expression-based drug sensitivity prediction revealed a differential treatment response in SARIFA-positive CRCs. In conclusion, SARIFA represents the H&E-based counterpart of an aggressive tumor biology, demonstrating a partial overlap with CMS1/4 and also adding a further biological layer related to lipid metabolism. Our findings underscore SARIFA-status as an ideal biomarker for refined patient stratification and novel drug developments, particularly given its cost-effective assessment based on routinely available H&E slides.

Incorporating Novel Technologies in Precision Oncology for Colorectal Cancer: Advancing Personalized Medicine

Colorectal cancer (CRC) is one of the most heterogeneous and deadly diseases, with a global incidence of 1.5 million cases per year. Genomics has revolutionized the clinical management of CRC by enabling comprehensive molecular profiling of cancer. However, a deeper understanding of the molecular factors is needed to identify new prognostic and predictive markers that can assist in designing more effective therapeutic regimens for the improved management of CRC. Recent breakthroughs in single-cell analysis have identified new cell subtypes that play a critical role in tumor progression and could serve as potential therapeutic targets. Spatial analysis of the transcriptome and proteome holds the key to unlocking pathogenic cellular interactions, while liquid biopsy profiling of molecular variables from serum holds great potential for monitoring therapy resistance. Furthermore, gene expression signatures from various pathways have emerged as promising prognostic indicators in colorectal cancer and have the potential to enhance the development of equitable medicine. The advancement of these technologies for identifying new markers, particularly in the domain of predictive and personalized medicine, has the potential to improve the management of patients with CRC. Further investigations utilizing similar methods could uncover molecular subtypes specific to emerging therapies, potentially strengthening the development of personalized medicine for CRC patients.

Identification of a ferroptosis-related gene signature predicting recurrence in stage II/III colorectal cancer based on machine learning algorithms

Background: Colorectal cancer (CRC) is one of the most prevalent cancer types globally. A survival paradox exists due to the inherent heterogeneity in stage II/III CRC tumor biology. Ferroptosis is closely related to the progression of tumors, and ferroptosis-related genes can be used as a novel biomarker in predicting cancer prognosis. Methods: Ferroptosis-related genes were retrieved from the FerrDb and KEGG databases. A total of 1,397 samples were enrolled in our study from nine independent datasets, four of which were integrated as the training dataset to train and construct the model, and validated in the remaining datasets. We developed a machine learning framework with 83 combinations of 10 algorithms based on 10-fold cross-validation (CV) or bootstrap resampling algorithm to identify the most robust and stable model. C-indice and ROC analysis were performed to gauge its predictive accuracy and discrimination capabilities. Survival analysis was conducted followed by univariate and multivariate Cox regression analyses to evaluate the performance of identified signature. Results: The ferroptosis-related gene (FRG) signature was identified by the combination of Lasso and plsRcox and composed of 23 genes. The FRG signature presented better performance than common clinicopathological features (e.g., age and stage), molecular characteristics (e.g., BRAF mutation and microsatellite instability) and several published signatures in predicting the prognosis of the CRC. The signature was further stratified into a high-risk group and low-risk subgroup, where a high FRG signature indicated poor prognosis among all collected datasets. Sensitivity analysis showed the FRG signature remained a significant prognostic factor. Finally, we have developed a nomogram and a decision tree to enhance prognosis evaluation. Conclusion: The FRG signature enabled the accurate selection of high-risk stage II/III CRC population and helped optimize precision treatment to improve their clinical outcomes.

Frailty and Colorectal Surgery: Review and Concept of Cancer Frailty

Frailty is characterized by reduced physiological reserves across multiple systems. In patients with frailty, oncological surgery has been associated with a high rate of postoperative complications and worse overall survival. Further, given that cancer and frailty can co-exist in the same patient, cancer and cancer-related symptoms can rapidly accelerate the progression of baseline frailty, which we have termed "cancer frailty". This distinction is clinically meaningful because the prioritization of interventions and the treatment outcomes may differ based on health conditions. Specifically, in patients with cancer frailty, improvements in frailty may be achieved via surgical removal of tumors, while prehabilitation may be less effective, which may in turn result in delayed treatment and cancer progression. In this review, we focused on challenges in the surgical treatment of non-metastatic colorectal cancers in patients with frailty, including those related to decision making, prehabilitation, and surgery. Potential recommendations for treating patients with cancer frailty are also discussed.

A correlation study affecting survival in patients after radical colon cancer surgery: A retrospective study

The objective of this study was to explore the relevant factors affecting the 5-year survival rate of patients after radical colon cancer surgery, and to provide some basis for improving the quality of life and prognosis of colon cancer patients. The clinical data of 116 colon cancer patients who underwent treatment in our hospital from January 2017 to December 2017 were retrospectively selected. Using the date of performing surgical treatment as the starting point and the completion of 5 years after surgery or patient death as the end point, all patients were followed up by telephone to count the 5-year survival rate and analyze the influence of each factor with the prognosis of colon cancer patients. Of the 116 patients, 14 patients were lost to follow-up. Of the 102 patients with complete follow-up, 33 patients were died, with an overall 5-year survival rate of 67.6%. After univariate analysis, it was found that distant metastasis (χ2 = 10.493, P = .001), lymph node metastasis (χ2 = 25.145, P < .001), depth of muscle infiltration (χ2 = 14.929, P < .001), alcohol consumption (χ2 = 15.263, P < .001), and preoperative obstruction (χ2 = 9.555, P = .002) were significantly associated with the prognosis of colon cancer patients. Multivariate logistic analysis showed that distant metastasis (odds ratio [OR]: 1.932, 95% confidence intervals [CI]: 1.272-2.934, P = .002), lymph node metastasis (OR: 1.219, 95% CI: 1.091-1.362, P < .001), and obstruction (OR: 1.970, 95% CI: 1.300-2.990, P < .001) were significant independent risk factors affecting the prognosis in patients after radical colon cancer surgery. In summary, preoperative obstruction, lymph node metastasis, and distant metastasis are independent factors influencing 5-year survival rate after radical colon cancer surgery. Patients with risk factors should be followed up more closely and reasonable postoperative adjuvant chemotherapy regimens should be used to improve long-term survival.

Impact on inadequate lymph node harvest on survival in T4N0 colorectal cancer: A would-be medical center experience in Taiwan

Insufficient lymph node harvest (< 12) may lead to incorrect classification of stage I and II disease. Many studies have indicated a poor prognosis with inadequate lymph node harvest in stages I to III, but few studies have demonstrated the relationship between low lymph node harvest and T4 disease. This study aimed to identify the influence of insufficient number of lymph nodes harvested on survival in T4N0 colorectal cancer. We enrolled patients with T4N0 colorectal cancer who underwent radical resection between 2010 and 2016. A total of 155 patients were divided into 2 groups; 142 patients had ≥ 12 harvested lymph nodes, and the other 13 had < 12 lymph nodes. All patients were followed up for at least 5 years. The primary outcome was the impact of the number of lymph nodes harvested on disease-free survival and overall survival, which were investigated using Kaplan-Meier survival techniques. There were no significant differences in recurrence rate, emergent or elective surgery, laparoscopic or open surgery, or chemotherapy between the 2 groups. Kaplan-Meier analyses showed no statistical differences in 5-year disease-free survival (P = .886) and 5-year overall survival (P = .832) between the groups. There were no significant differences in disease-free survival and overall survival between patients with adequate (≥ 12) and inadequate (< 12) lymph node harvest in T4N0 colorectal cancers.

Benefit of Uracil-Tegafur Used as a Postoperative Adjuvant Chemotherapy for Stage IIA Colon Cancer

Background and Objectives: Postoperative adjuvant therapy with uracil and tegafur (UFT) is often used for stage II colon cancer in Japan, but a limited number of studies have investigated the effects of UFT in these patients. Materials and Methods: We conducted a population-based cohort study in patients with resected stage II colon cancer comparing the outcomes after postoperative adjuvant chemotherapy with UFT with an observation-only group. The data were collected from the Taiwan National Health Insurance Research Database from 2000 to 2015. The outcomes of the study were disease-free survival (DFS) and overall survival (OS). The hazard ratios (HRs) were calculated using multivariate Cox proportional hazard regression models. Results: No differences in the DFS and OS were detected between the UFT (1137 patients) and observation (2779 patients) cohorts (DFS: adjusted HR 0.702; 95% confidence interval (CI) 0.489-1.024; p = 0.074) (OS: adjusted HR 0.894; 95% CI 0.542-1.186; p = 0.477). In the subgroup analyses of the different substages, UFT prolonged DFS in patients with stage IIA colon cancer (adjusted HR 0.652; 95% CI 0.352-0.951; p = 0.001) compared with DFS in the observation cohort, but no differences in the OS were detected (adjusted HR 0.734; 95% CI 0.475-1.093; p = 0.503). Conclusions: Our results show that DFS improved significantly in patients with stage IIA colon cancer receiving UFT as a postoperative adjuvant chemotherapy compared with DFS in the observation group.

CINSARC signature outperforms gold-standard TNM staging and consensus molecular subtypes for clinical outcome in stage II-III colorectal carcinoma

The outcome of stage II-III colorectal cancer (CRC) is highly variable and therapeutic choice is currently based on TNM staging with a few additional biomarkers. However, studies show that some stage III patients have a better prognosis than some stage II patients. A promising consensus molecular (CMS) classification with prognostic relevance has been developed, but it is not used in daily practice. Our team developed CINSARC, a 67-gene expression prognostic signature, whose prognostic value has been demonstrated in many cancer types. It is applicable to formalin-fixed, paraffin-embedded (FFPE) blocks using NanoString® technology. We investigated whether it could predict outcome in stage II-III CRC. We established the CINSARC classification on the TCGA retrospective cohort comprising 297 stage II-III CRC patients using RNA sequencing and on a second independent cohort comprising 169 cases using NanoString® technology. We compared its recurrence-free and overall survival prognostic value with TNM staging and CMS classification. In the TCGA cohort, we showed that CINSARC significantly splits the population of stage II-III CRC into two groups with different progression-free interval (P = 1.68 × 10^-2; HR = 1.87 [1.11-3.16]) and overall survival (P = 3.73 × 10^-3; HR = 2.45 [1.31-4.59]) and is a strong prognostic factor in multivariate analysis, outperforming TNM staging and CMS classification. We validated these results in the second cohort by applying CINSARC on FFPE samples with Nanostring® technology. CINSARC is a ready-to-use tool with a robust independent prognostic value in stage II-III CRC.

Preoperative Hepatic and Regional Arterial Chemotherapy in Patients Who Underwent Curative Colorectal Cancer Resection: A Prospective, Multi-center, Randomized Controlled Trial

OBJECTIVE

To evaluate the effects of the addition of preoperative hepatic and regional arterial chemotherapy (PHRAC) on prognosis of stage II and III colorectal cancer (CRC) in a multicenter setting.

SUMMARY OF BACKGROUND DATA

Our previous single-center pilot trial suggested that PHRAC in combination with surgical resection could reduce the occurrence of liver metastasis (LM) and improve survival in CRC patients.

METHODS

A prospective multi-center randomized controlled trial was conducted from December 2008 to December 2012 at 5 hospitals in China. Eligible patients with clinical stage II or III CRC who underwent curative resection were randomized to receive PHRAC plus adjuvant therapy (PHRAC arm) or adjuvant therapy alone (control arm). The primary endpoint was DFS. Secondary endpoints were cumulative LM rates, overall survival (OS), and safety (NCT00643877).

RESULTS

A total of 688 patients from 5 centers in China were randomly assigned (1:1) to each arm. The five-year DFS rate was 77% in the PHRAC arm and 65% in the control arm (HR = 0.61, 95% CI 0.46-0.81; P = 0.001). The 5-year LM rates were 7% and 16% in the PHRAC and control arms, respectively (HR = 0.37, 95% CI 0.22-0.63; P < 0.001). The 5-year OS rate was 84% in the PHRAC arm and 76% in the control arm (HR = 0.61, 95% CI 0.43-0.86; P = 0.005). There were no significant differences regarding treatment related morbidity or mortality between the two arms.

CONCLUSIONS

The addition of PHRAC could improve DFS in patients with stage II and III CRC. It reduced the incidence of LM and improved OS without compromising patient safety.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00643877.

Perineural invasion and number of retrieved lymph nodes are prognostic factors for T2N0 colon cancer

PURPOSE

The prognosis of pathological T2N0 colon cancer has not been adequately investigated. This study aimed to determine the prognostic factors for pathological T2N0 colon cancer by comparing it with those for pathological T3N0 colon cancer.

METHODS

We retrospectively reviewed patients with primary colon cancer who underwent curative resection between January 2007 and December 2015 and included 889 patients with postoperative pathological T2-3N0M0 disease. The clinicopathological characteristics were analyzed to identify the independent prognostic factors.

RESULTS

Pathological T2 (n = 185, 20.8%) and T3 (n = 704, 79.2%) tumors showed no difference in the 5-year disease-free survival (5Y DFS) rate (95.8% vs. 93.2%, p = 0.257) after a median follow-up of 55 months (range, 1-106 months). Multivariate Cox regression analysis showed that perineural invasion (hazard ratio [HR] = 2.041, 95% confidence interval [CI] 1.122-3.712, p = 0.019) and number of retrieved lymph nodes < 12 (HR = 2.994, 95% CI 1.327-6.753, p = 0.008) were independent prognostic factors for DFS. Pathological T2 tumors with poor prognostic factors showed similar 5Y DFS as that of T3 tumors with poor prognostic factors (88.9% vs. 88.6%, p = 0.916), but not with T3 tumors without poor prognostic factors (88.9% vs. 95.0%, p = 0.089).

CONCLUSION

Pathological T2N0 colon cancer showed oncologic outcomes similar to that of T3N0 colon cancer. Therefore, more intensive surveillance is necessary for patients with high-risk T2N0 colon cancer.

Identification prognosis-associated immune genes in colon adenocarcinoma

Colon adenocarcinoma (COAD) is one of the most prevalent malignant tumors worldwide. Immune genes (IGs) have a considerable correlation with tumor initiation and prognosis. The present paper aims to identify the prognosis value of IGs in COAD and conduct a prognosis model for clinical utility. Gene expression data of COAD were downloaded from The Cancer Genome Atlas (TCGA), screening and analyzing differentially expressed IGs by bioinformatics. Core genes were screened by univariate and multivariate Cox regression analyses. Survival analysis was appraised by the Kaplan–Meier method and the log-rank test. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Gene Set Enrichment Analysis (GSEA) were used to identify IGs’ relevant signal pathways. We predicted the overall survival (OS) by nomogram. Finally, a prognosis model was conducted based on 12 IGs (SLC10A2, CXCL3, NOX4, FABP4, ADIPOQ, IGKV1-33, IGLV6-57, INHBA, UCN, VIP, NGFR, and TRDC). The risk score was an independent prognostic factor, and a nomogram could accurately predict the OS of individual COAD patients. These results were validated in GSE39582, GSE12945, and GSE103479 cohorts. Functional enrichment analysis demonstrated that these IGs are mainly enriched in hormone secretion, hormone transport, lipid transport, cytokine–cytokine receptor interaction, and peroxisome proliferators-activated receptor signaling pathway. In summary, the risk score is an independent prognostic biomarker. We also excavated several IGs related to COAD’s survival and maybe potential biomarkers for COAD diagnosis and treatment.

A Novel TNM Classification for Colorectal Cancers based on the Metro-ticket Paradigm

Background: Several revisions of the TNM classifications for colorectal cancer (CRC) have acknowledged that the oncological outcomes of stage IIB/IIC CRC are worse than those of stage IIIA. We aimed to develop a novel TNM (nTNM) classification based on the metro-ticket paradigm. Methods: We identified eligible CRC patients from the Surveillance, Epidemiology, and End Results database. The nTNM was developed using distance from the origin on a Cartesian plane incorporating the pN (x-axis) and pT (y-axis) stages, and was compared with the AJCC TNM classification. The areas under the curves (AUCs), calibration curves, and Akaike's information criterion (AIC) were used to evaluate the predictive performances of the two classifications. Clinical benefits were further estimated by decision curve analyses. The validation cohort was applied to validate these findings. Results: A total of 58,192 CRC patients (40,736 training cohort, 17,456 validation cohort) were finally included. In the training cohort, 18,476 patients (45.4%) experienced upstaging and 15,907 patients (39.0%) experienced downstaging in the nTNM classification compared with the TNM classification. Taking the prognosis of stage I as the reference, survival decreased with increasing nTNM stage. The nTNM classification showed better discrimination (AUC, 0.678 vs. 0.667, P<0.001), model-fitting (AIC, 236,525 vs. 237,741), and clinical benefits than the TNM classification. Similar results were found in the validation cohort. Conclusions: The nTNM classification for CRC has better predictive performances and superior accuracy for predicting prognosis compared with the TNM classification. The nTNM classification should therefore be considered in future revisions of the TNM classification.

Staging Paradox and Discrepancy in Adjuvant Chemotherapy in Patients with T4N0, T1-2N1, and T3N1 Colon Cancer

BACKGROUND

A survival paradox between T4N0 (stage IIB/C) and T3N1 (stage IIIB) colon cancer has been rarely reported. The indication and regimen of adjuvant chemotherapy are separately described in the guidelines. This study aimed to elucidate the prognostic factors and investigate proper adjuvant treatment in colon cancer patients at these stages.

METHODS

Patients who underwent R0 resection for pathological T4N0 (n = 49), T1-2N1 (n = 31), or T3N1 (n = 82) colon cancer between 2008 and 2016 at a single institute were retrospectively reviewed. The clinicopathological characteristics, status of adjuvant chemotherapy, and oncologic outcomes of patients with T4N0 tumors were compared with those of patients with T1-2N1 and T3N1 tumors.

RESULTS

The biological characteristics of T4N0 tumors were more aggressive compared with the characteristics of T1-2N1 tumors and were similar to those of T3N1 tumors. The usage rate of oxaliplatin as an adjuvant chemotherapy was significantly lower in T4N0 patients than in T1-2N1 and T3N1 patients. The rate of local recurrence was the highest in patients with T4N0 tumors, and the survival outcomes for patients with T4N0 tumors were significantly worse compared with those of T1-2N1 patients and were similar to those of T3N1 patients. A multivariate analysis revealed that lack of adequate use of oxaliplatin for adjuvant chemotherapy was the only prognostic factor.

CONCLUSIONS

T4N0 colon cancer had similar oncological characteristics and survival outcomes to T3N1 colon cancer. Systematic adjuvant chemotherapy, including oxaliplatin, should be incorporated into the therapy for T4N0 patients as well as T3N1 patients.

Re-Evaluation of the Survival Paradox Between Stage IIB/IIC and Stage IIIA Colon Cancer

Objective

We conducted this large population-based study to re-evaluate the survival paradox between stage IIB/C and stage IIIA colon cancer based on the newest staging criteria.

Methods

Colon cancer patients were recruited from the Surveillance, Epidemiology, and End Results (SEER) database using SEER*Stat software (version 8.3.4) with strict inclusion criteria. We used Chi-square test to compare categorical variables between patients diagnosed with stage IIB/IIC and stage IIIA colon cancer. Survival probabilities were then assessed using the Kaplan–Meier method. Cox proportional hazards models were used to analyze hazard ratios (HRs) and 95% confidence intervals (CIs) of clinicopathologic characteristics in stage IIB/IIC and stage IIIA colon cancer patients.

Results

In the current study, a total of 9,227 eligible colon cancer patients were collected from the SEER database between 2010 and 2015. It was found that stage IIIA had 66.4% decreased risk of colon cancer-specific mortality compared with stage IIB (HR = 0.336, 95%CI = 0.286–0.394 for stage IIIA, P < 0.001, using stage IIB as the reference) after the adjustment for other known prognostic factors. And T1N2a colon cancer had significantly lower 5-year overall survival (OS) rate compared with T2N1 disease (74.7% vs. 57.1%, P = 0.018).

Conclusions

Our study confirmed the existence of survival paradox between stage IIB/IIC and stage IIIA colon cancer based on the newest staging criteria. What is more, the subgroup analyses revealed that T1N2a had the least influence on the survival paradox. N2a colon cancer seemed to be associated with worse prognosis than T2 disease, which would give us a better understanding of tumor biology of colon cancer and be conducive to the refinement of individualized treatment regimens in stage III disease.

Tissue-Infiltrating Lymphocytes as a Predictive Factor for Recurrence in Patients with Curatively Resected Colon Cancer: A Propensity Score Matching Analysis

BACKGROUND

In patients with colorectal cancer, the rate of recurrence increases as the histologic stage progresses. However, the prediction of recurrence in individual patients is difficult. Many studies have reported on the relation between outcomes and tissue-infiltrating lymphocytes (TILs). The aim of our study was to clarify the relation between TILs and oncologic outcomes in patients with colon cancer using propensity score matching analysis.

METHODS

The study group comprised 513 patients with colon cancer who received curative resection. By using propensity score matching for sex, age, tumor location, T stage, N stage, histologic type, and adjuvant therapy as conventional prognostic factors, 61 patients with recurrence and 61 patients with no recurrence were selected. Hematoxylin-eosin staining and immunohistochemical staining using CD3, CD8, CD4, and FoxP3 were performed for lymphocytes in the primary tissue. The results were evaluated separately in the whole tumor, the central part, and the invasive margin.

RESULTS

The median follow-up period was 53 months. Among the 513 patients, 70 had recurrence and 443 had no recurrence. In the comparison of outcomes between the 61 patients with recurrence and the 61 patients with no recurrence, univariate analysis showed that the disease-free survival rate was significantly higher among the patients with positive TILs in the whole tumor and in the invasive margin (p = 0.016 and p = 0.012, respectively) and with CD8+ cells in the central part (p = 0.039) than among those with negative results. A multivariate analysis showed that TILs in the invasive margin (hazard ratio 1.81; 95% confidence interval, 1.03-3.05; p = 0.037) and CD8+ cell density in the central part (hazard ratio 1.76; 95% confidence interval, 1.07-2.93; p = 0.023) were prognostic factors that were independent from conventional prognostic factors.

CONCLUSIONS

In patients with curatively resected colon cancer, TILs in the invasive margin and CD8+ cell density in the central part may be prognostic factors suggesting host antitumor immune response.