Survival in Resected Stage II Colorectal Cancer Is Dependent on Tumor Depth, Vascular Invasion, Postoperative CEA Level, and The Number of Examined Lymph Nodes

Elevated postoperative carcinoembryonic antigen guides adjuvant chemotherapy for stage II colon cancer: a multicentre cohort retrospective study

Most clinical doctors rely on high-risk factors recommended by guidelines to decide whether to undergo adjuvant chemotherapy for stage II colon cancer. However, these high-risk factors do not include postoperative carcinoembryonic antigen (CEA). This study aims to explore the elevation of postoperative CEA as a risk factor, in addition to other high-risk factors, to guide adjuvant chemotherapy for patients with stage II colon cancer. A retrospective analysis was conducted on stage II colon cancer patients who underwent curative surgery at Yunnan Cancer Hospital and The Sixth Affiliated Hospital of Sun Yat-Sen University from April 2008 to January 2019. Patients were classified into three groups based on high-risk factors recommended by guidelines and postoperative CEA levels: low-risk with normal postoperative CEA, low-risk with elevated postoperative CEA and high-risk. COX regression analysis was used to identify independent prognostic factors affecting patients' recurrence free survival (RFS). The Kaplan-Meier method was used to create the patients' RFS curve. The restricted cubic spline (RCS) curve was used to assess the correlation between postoperative CEA and RFS on a continuous scale. Among 761 patients, there were 444 males (62.01%), with a median [IQR] age of 58.0 (18.0-88.0) years. A group of 425 high-risk patients had a 3-year RFS of 82.2% (95% CI 78.5-86.1%), while a group of 291 low-risk patients had a 3-year RFS of 89.7% (95% CI 86.1-93.5%). There was a statistically significant difference between the two groups (HR 1.83; 95% CI 1.22-2.74; P = 0.0067). Among them, the 3-year RFS of 261 low-risk patients with normal postoperative CEA was 93.6% (95% CI 90.5-96.8%), while the 3-year RFS of 30 low-risk patients with elevated postoperative CEA was 57.3% (95% CI 41.8-71.4%). There was a significant difference compared to the 3-year RFS of 425 high-risk patients (overall log-rank P < 0.0001). The multivariate analysis adjusted by the COX proportional hazards model showed that low-risk patients with elevated postoperative CEA patients (HR 14.95, 95% CI 4.51-49.63, P < 0.0001) was independently associated with a 3-year RFS. The restricted cubic spline model showed that in stage II colon cancer patients with tumor diameter > 1.955 ng/mL, the risk of postoperative recurrence increased with increasing postoperative CEA levels. Patients with elevated postoperative CEA levels have a significantly increased risk of recurrence. They should be included as high-risk factors to guide adjuvant chemotherapy for stage II colon cancer.

Construction of machine learning models based on transrectal ultrasound combined with contrast-enhanced ultrasound to predict preoperative regional lymph node metastasis of rectal cancer

Purpose

Constructing a machine learning model based on transrectal ultrasound (TRUS) combined with contrast-enhanced ultrasound (CEUS) to predict preoperative regional lymph node metastasis (RLNM) of rectal cancer and provide new references for decision-making.

Materials and methods

233 patients with rectal cancer were enrolled and underwent TRUS and CEUS prior to surgery. Clinicopathological and ultrasound data were collected to analyze the correlation of RLNM status, clinical features and ultrasound parameters. A 75% training set and 25% test set were utilized to construct seven machine learning algorithms. The DeLong test was used to assess the model's diagnostic performance, then chose the best one to predict RLNM of rectal cancer.

Results

The diagnostic performance was most dependent on the following: MMT difference (36), length (30), location (29), AUC ratio (27), and PI ratio (24). The prediction accuracy, sensitivity, specificity, precision, and F1 score range of KNN, Bayes, MLP, LR, SVM, RF, and LightGBM were (0.553-0.857), (0.000-0.935), (0.600-1.000), (0.557-0.952), and (0.617-0.852), respectively. The LightGBM model exhibited the optimal accuracy (0.857) and F1 score (0.852). The AUC for machine learning analytics were (0.517-0.941, 95% CI: 0.380-0.986). The LightGBM model exhibited the highest AUC (0.941, 95% CI: 0.843-0.986), though no statistic significant showed in comparison with the SVM, LR, RF, and MLP models (P > 0.05), it was significantly higher than that of the KNN and Bayes models (P < 0.05).

Conclusion

The LightGBM machine learning model based on TRUS combined with CEUS may help predict RLNM prior to surgery and provide new references for clinical treatment in rectal cancer.

High postoperative carcinoembryonic antigen as an indicator of high‑risk stage II colon cancer

Postoperative carcinoembryonic antigen (post-CEA) has recently been reported to be a reliable prognostic factor for colon cancer. However, most clinicians decide whether or not to conduct adjuvant chemotherapy (AC) for stage II colon cancer according to major guidelines, which do not include post-CEA in their high-risk criteria. The present study aimed to assess post-CEA in stage II colon cancer for which the significance of AC is unknown. The present study analyzed 199 consecutive patients with stage II colon cancer who underwent curative surgery between January 2007 and December 2016. The CEA value was considered high when it was ≥5.0 ng/ml. The prognostic value of high post-CEA values was assessed. Overall, 19 patients exhibited high post-CEA levels. Kaplan-Meier survival curve analysis demonstrated that patients with high post-CEA levels had significantly worse relapse-free survival (RFS) and overall survival (OS) than those with normal post-CEA [RFS, 63.5 (high post-CEA) vs. 88.0% (normal post-CEA), P=0.003; OS, 76.5 (high post-CEA) vs. 96.8% (normal post-CEA), P<0.001]. Multivariate analysis demonstrated that high post-CEA remained a significant independent risk factor for worse RFS [hazard ratio (HR), 3.98; P=0.006]. The same was also demonstrated for patients without AC (HR, 5.43; P=0.008). To the best of our knowledge, the present study was the first to demonstrate that high post-CEA levels may be an indicator of high-risk stage II colon cancer, even for patients without AC. These results highlight the need for a multicenter prospective study.

Clinical Significance of and Predictive Risk Factors for the Postoperative Elevation of Carcinoembryonic Antigen in Patients With Non-Metastatic Colorectal Cancer

Background

Recently, a few researches focus on the correlation between postoperative carcinoembryonic antigen (post-CEA) and the outcome of colorectal cancer (CRC), but none investigates the predictive value of post-CEA in a prognostic model. Besides, current recommendations on the frequency of post-CEA surveillance are not individualized and well followed. There is an absence of identification of patients who are more likely to have abnormal post-CEA levels and need more frequent CEA measurements.

Methods

Consecutive CRC patients who underwent curative surgery were enrolled and randomly divided into the discovery (n=352) and testing cohort (n=233). Impacts of preoperative CEA (pre-CEA) and post-CEA on prognosis were assessed. Cox regression model was applied to develop prognostic nomograms, which were validated by the concordance index (C-index), calibration curve, and receiver operating characteristic curve (ROC) analysis. And prediction improvement of the nomograms was assessed with net reclassification improvement (NRI) and integrated discrimination improvement (IDI). Logistic regression was used to identify predictive risk factors and construct the prediction model for post-CEA elevation.

Results

Post-CEA independently predicted overall survival (OS) and disease-free survival (DFS), while pre-CEA did not. Post-CEA elevation represented higher risks in patients with normal pre-CEA, compared to those with persistent elevated CEA. The nomograms for OS and DFS were established with body mass index, tumor differentiation, N stage, lymphocyte-to-monocyte ratio, and post-CEA. The nomograms showed good calibration and superior discrimination than pTNM stage, with the C-index of 0.783 and 0.759 in the discovery set and 0.712 and 0.774 in the testing set for OS and DFS, respectively. Comparisons between models using IDI and NRI implied that the nomograms performed better than pTNM stage and the predictive power could be improved with the addition of post-CEA. The prediction model for post-CEA elevation was established with age, platelet-to-lymphocyte ratio, preoperative CA19-9, and pre-CEA. The AUC of the model in the two cohorts was 0.802 and 0.764, respectively.

Conclusions

Elevated post-CEA was a strong indicator of poor prognosis. The addition of post-CEA significantly enhanced the performance of prognostic nomograms. And the prediction model for post-CEA elevation may help identify patients who ought to reasonably receive more intensive postoperative surveillance of CEA levels.

Association Between Serum Carcinoembryonic Antigen Levels at Different Perioperative Time Points and Colorectal Cancer Outcomes

Background

Whether elevated postoperative serum carcinoembryonic antigen (CEA) levels are prognostic in patients with stage II colorectal cancer (CRC) remains controversial.

Patients and Methods

Primary and sensitivity analysis populations were obtained from a retrospective, multicenter longitudinal cohort including consecutive patients without neoadjuvant treatment undergoing curative resection for stage I–III CRC. Serum CEA levels before (CEA_pre-m1) and within 1 (CEA_post-m1), 2–3 (CEA_post-m2–3), and 4–6 months (CEA_post-m4–6) after surgery were obtained, and their associations with recurrence-free survival (RFS) and overall survival (OS) were assessed using Cox regression. Sensitivity and subgroup analyses were performed.

Results

Primary and sensitivity analysis populations included 710 [415 men; age, 54.8 (11.6) years] and 1556 patients [941 men; age, 56.2 (11.8) years], respectively. Recurrence hazard ratios (HRs) in the elevated CEA_pre-m1, CEA_post-m1, CEA_post-m2–3, and CEA_post-m4–6 groups were 1.30 (95% CI: 0.91–1.85), 1.53 (95% CI: 0.89–2.62), 1.88 (95% CI: 1.08–3.28), and 1.15 (95% CI: 0.91–1.85), respectively. The HRs of the elevated CEA_pre-m1, CEA_post-m1, CEA_post-m2–3, and CEA_post-m4–6 groups for OS were 1.09 (95% CI: 0.60–1.97), 2.78 (95% CI: 1.34–5.79), 2.81 (95% CI: 1.25–6.30), and 3.30 (95% CI: 1.67–.536), respectively. Adjusted multivariate analyses showed that both in the primary and sensitivity analysis populations, elevated CEA_post-m2–3, rather than CEA_pre-m1, CEA_post-m1, and CEA_post-m4–6, was an independent risk factor for recurrence, but not for OS. The RFS in the elevated and normal CEA_post-m2–3 groups differed significantly among patients with stage II disease [n = 266; HR, 2.89; 95% CI, 1.02–8.24 (primary analysis); n = 612; HR, 2.69; 95% CI, 1.34–5.38 (sensitivity analysis)].

Conclusions

Elevated postoperative CEA levels are prognostic in patients with stage II CRC, with 2–3 months after surgery being the optimal timing for CEA measurement.

Prognostic value of the ratio of carcinoembryonic antigen concentration to maximum tumor diameter in patients with stage II colorectal cancer

Background

Recently, a study from our center indicated that the ratio of preoperative carcinoembryonic antigen (CEA) concentration to maximum tumor diameter (DMAX) may be a prognostic marker for patients with rectal cancer. Therefore, the study aimed to evaluate whether this ratio (CEA/DMAX) has prognostic value for patients with stage II colorectal cancer (CRC).

Methods

A prospectively maintained database was searched for patients with pathologically confirmed stage II CRC who underwent surgery between January 2010 and March 2019. Patients were stratified according to the mean CEA/DMAX value into low and high CEA/DMAX groups. Kaplan-Meier, univariable, and multivariable Cox regression analyses were used to evaluate whether the CEA/DMAX could predict overall survival (OS) and disease-free survival (DFS). Nomograms were constructed in terms of the results of multivariable Cox regression analyses.

Results

The study included 2,499 patients with stage II CRC. The mean CEA/DMAX value was 2.33 (ng/mL per cm). Kaplan-Meier analyses revealed that, relative to the low CEA/DMAX group, the high CEA/DMAX group had significantly poorer OS (67.31% vs. 85.02%, P<0.001) and DFS (61.41% vs. 77.10%, P<0.001). The multivariable Cox regression analysis revealed that CEA/DMAX independently predicted OS (hazard ratio: 2.58, 95% confidence interval: 1.51-4.38, P<0.001) and DFS (hazard ratio: 1.97, 95% confidence interval: 1.38-2.83, P<0.001). Two simple-to-use nomograms comprising CEA/DMAX, age, T stage, and lymphovascular invasion were developed to predict 1-, 3-, and 5-year rates of OS and DFS among patients with stage II CRC. The nomograms had good performance based on the concordance index, receiver operating characteristic (ROC) curve analysis, and calibration curves. Subgroup analyses further confirmed that a high CEA/DMAX was associated with poor OS and DFS among patients with stage II colon cancer and among patients with stage II rectal cancer (both P<0.05).

Conclusions

Among patients with stage II CRC, a high CEA/DMAX independently predicted poor OS and DFS, and the predictive abilities were also observed in subgroup analyses of patients with stage II colon cancer or rectal cancer. Furthermore, we developed two nomograms that had good accuracy for predicting the prognosis of stage II CRC.

Association of perioperative serum carcinoembryonic antigen level and recurrence in low-risk stage IIA colon cancer

Background

The purpose is to investigate prognosis according to serum CEA levels before and after surgery in patients with stage IIA colon cancer who do not show high-risk features.

Methods

Among the patients diagnosed with colon adenocarcinoma between April 2011 and December 2017, 462 patients were confirmed as low-risk stage IIA after surgery and enrolled. The ROC curve was used to determine cut-off values of pre- and postoperative CEA. Patients were classified into three groups using these new cut-off values.

Results

All recurrence occurred in 52 of 463 patients (11.2%). However, recurrence in group H was 15.9%, which was slightly higher than the other two groups (P = 0.04). Group L and M showed 10.5% and 12.8% overall survival, group H was higher at 21.0% (P = 0.005). Recurrence was the only risk factor in group H was significantly higher in group L (HR 2.008, 95% CI, 1.123–3.589, P = 0.019). Mortality was similar to recurrence (HR 1.975, 95% CI 1.091–3.523, P = 0.044).

Conclusion

Among patients with low-risk stage IIA colon cancer, recurrence and mortality rates were higher when perioperative serum CEA levels were above a certain level. Therefore, high CEA level should be considered a high-risk feature and adjuvant chemotherapy should be performed.

Stage migration resulting from inadequate number of examined lymph nodes impacts prognosis in stage II colon cancer after radical surgery

PURPOSE

We evaluated the impact of examined lymph node (ELN) number on the prognosis of stage II colon cancer after radical surgery and developed a novel prognostic scoring system by combining primary tumor extension (pT) and ELN number for reclassification of stage II colon cancer.

METHODS

Three cohorts of patients diagnosed with colon cancer between 2004 and 2010 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate analyses were performed to evaluate the relationship between factors and patients' survival including cause-specific survival (CSS) and overall survival (OS). Survival curves from subgroups were plotted by the Kaplan-Meier method and compared by the log-rank test.

RESULTS

Cohort 1 and cohort 2 consisted of 13,960 and 5312 stage II colon cancer patients, respectively. Cohort 3 consisted of 4713 stage III patients. Factors including ELN, age, and pT were found to be associated with patients' survival in cohorts 1 and 2. Patients who were older or with smaller tumors were more likely to experience inadequate ELN. Patients with a higher score, as calculated by the novel scoring system, showed worse survival. Compared with stage III colon cancer patients, stage II patients with high scores had a comparable or even worse survival than stage IIIA and IIIB patients.

CONCLUSION

Inadequate ELN leads to understaging in stage II colon cancer and predicts inferior prognosis. Our analyses show that the novel prognostic scoring system, consisting of combined pT and ELN, quantified stage migration effect and can be applied to the reclassification of stage II colon cancer.

A nomogram for predicting overall survival in patients with resected non-small cell lung cancer treated with chemotherapy

Background

Chemotherapy is a common treatment for patients with resected non-small cell lung cancer (NSCLC). However, there are few models for predicting the survival outcomes of these patients. Here, we developed a clinical nomogram for predicting overall survival (OS) in this cohort.

Methods

A total of 16,661 patients with resected NSCLC treated with chemotherapy were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. We identified prognostic factors and integrated them into a nomogram. The model was subjected to bootstrap internal validation using the SEER database and external validation using a database in China and the National Cancer Database (NCDB). The model’s predictive accuracy and discriminative ability were tested by calibration and concordance index (C-index).

Results

Age, sex, number of dissected lymph nodes, extent of surgery, N stage, T stage, and grade were independent factors for OS and were integrated into the model. The calibration curves for probability of 1-, 3-, and 5-year OS showed excellent agreement between the predicted and actual survivals. The C-index of the nomogram was higher than that of the Tumor-Node-Metastasis staging system for predicting OS (training cohort, 0.62 vs. 0.58; China cohort, 0.68 vs. 0.63; NCDB cohort, 0.59 vs. 0.57).

Conclusions

We developed a nomogram that can present individual prediction of OS for patients with resected NSCLC who are undergoing chemotherapy. This practical prognostic tool may help clinicians in treatment planning.

No benefit of more intense follow-up after surgery for colorectal cancer in the risk group with elevated CEA levels - An analysis within the COLOFOL randomized clinical trial

BACKGROUND

Patients with colorectal cancer were examined to determine (1) whether elevated carcinoembryonic antigen (CEA) levels, either before treatment or after surgery, was associated with an increased risk of overall or colorectal cancer-specific mortality or recurrence, and (2) whether high intensity follow-up would benefit those patients.

MATERIALS AND METHODS

Post-hoc analysis based on 2509 patients that underwent surgery for colorectal cancer, stage II or III, in the COLOFOL randomized trial with 5-year follow-up. Serum CEA levels were ascertained before treatment and one month after surgery. Follow-up examinations included computed tomography of the thorax and abdomen and serum CEA sampling. Patients were randomized to examinations at either 6, 12, 18, 24, and 36 months (high-intensity group) or at 12 and 36 months after surgery (low-intensity group). Levels of CEA >5 μg/l were defined as elevated.

RESULTS

Elevated CEA levels before treatment were associated with increased risk of recurrence (hazard ratio [HR], 1.49; 95% confidence interval [CI]: 1.22-1.83), colorectal cancer-specific mortality (HR, 1.44; 95% CI: 1.08-1.91), and overall mortality (HR, 1.38; 95% CI: 1.07-1.78). Elevated CEA levels after surgery were associated with increased colorectal cancer-specific mortality (HR, 1.68; 95% CI: 1.08-2.61) and overall mortality (HR, 1.79; 95% CI: 1.22-2.63). The intensity of the follow-up regimen had no effect on 5-year outcomes in patients with elevated CEA levels.

CONCLUSION

Both pre-treatment and post-surgery elevated serum CEA levels were associated with increased overall and cancer-specific mortality. Intensified follow-up showed no benefit over low-intensity follow-up in this high-risk group of patients with elevated CEA levels.

Evaluation of the prognostic relevance of the recommended minimum number of lymph nodes in colorectal cancer-a propensity score analysis

PURPOSE

Nodal status in colorectal cancer (CRC) is an important prognostic factor, and adequate lymph node (LN) staging is crucial. Whether the number of resected and analysed LN has a direct impact on overall survival (OS), cancer-specific survival (CSS) and disease-free survival (DFS) is much discussed. Guidelines request a minimum number of 12 LN to be analysed. Whether that threshold marks a prognostic relevant cut-off remains unknown.

METHODS

Patients operated for stage I-III CRC were identified from a prospectively maintained database. The impact of the number of analysed LN on OS, CSS and DFS was assessed using Cox regression and propensity score analysis.

RESULTS

Of the 687 patients, 81.8% had ≥ 12 LN resected and analysed. Median LN yield was 17.0 (IQR 13.0-23.0). Resection and analysis of ≥ 12 LN was associated with improved OS (HR = 0.73, 95% CI: 0.56-0.95, p = 0.033), CSS (HR 0.52, 95% CI: 0.31-0.85, p = 0.030) and DFS (HR = 0.73, 95% CI: 0.57-0.95, p = 0.030) in multivariate Cox analysis. After adjusting for biasing factors with propensity score matching, resection of ≥ 12 LN was significantly associated with improved OS (HR = 0.59; 95% CI: 0.43-0.81; p = 0.002), CSS (HR = 0.34; 95% CI: 0.20-0.60; p < 0.001) and DFS (HR = 0.55; 95% CI: 0.41-0.74; p < 0.001) compared to patients with < 12 LN.

CONCLUSION

Eliminating biasing factors by a propensity score matching analysis underlines the prognostic importance of the number of analysed LN. The set threshold marks the minimum number of required LN but nevertheless represents a cut-off regarding outcome in stage I-III CRC. This analysis therefore highlights the significance and importance of adherence to surgical oncological standards.

Identification of Genomic Alterations of Perineural Invasion in Patients with Stage II Colorectal Cancer

Purpose

The molecular mechanism of perineural invasion (PNI) in stage II colorectal cancer (CRC) remains not to be defined clearly. This study aims to identify the genomic aberrations related to PNI in stage II CRC.

Patients and Methods

Using array-based comparative genomic hybridization (array-CGH), primary tumor tissues and paracancerous normal tissues of stage II CRC with PNI and without PNI were analyzed. We identified genomic aberrations by using Genomic Workbench and MD-SeeGH and validated the aberrations of selected genes by real-time polymerase chain reaction (PCR). Gene ontology (GO) and pathway analysis were performed to determine the most likely biological effects of these genes.

Results

The most frequent gains in stage II CRC were at 7q11.21-q11.22, 8p11.21, 8p12-p11.23, 8q11.1-q11.22, 13q12.13-q12.2, and 20q11.21-q11.23 and the most frequent losses were at 17p13.1-p12, 8p23.2, and 118q11.2-q23. Four high-level amplifications at 8p11.23-p11.22, 18q21.1, 19q11-q12, and 20q11.21-q13.32 and homozygous deletions at 20p12.1 were discovered in Stage II CRC. Gains at 7q11.21-q22.1, 16p11.2, 17q23.3-q25.3, 19p13.3-p12, and 20p13-p11.1, and losses at 11q11-q12.1, 11p15.5-p15.1, 18p11.21, and 18q21.1-q23 were more commonly found in patients with PNI by frequency plot comparison together with detailed genomic analysis. It is also observed that gains at 8q11.1-q24.3, 9q13-q34.3, and 13q12.3-q13.1, and losses at 8p23.3-p12, 17p13.3-p11.2, and 21q22.12 occurred more frequently in patients without PNI. Further validation showed that the expression of FLT1, FBXW7, FGFR1, SLC20A2 and SERPINI1 was significantly up-regulated in the NPNI group compared to the PNI group. GO and pathway analysis revealed some genes enriched in specific pathways.

Conclusion

These involved genomic changes in the PNI of stage II CRC may be useful to reveal the mechanisms underlying PNI and provide candidate biomarkers.

Prognostic Value of EGFR Expression for Patients With Stage III Colorectal Cancer Receiving Fluoropyrimidine Metronomic Maintenance Therapy After Radical Resection and Adjuvant Oxaliplatin-Based Chemotherapy

This study evaluated the survival effects of metronomic maintenance therapy with oral fluoropyrimidine in patients with stage III colorectal cancer (CRC) according to epidermal growth factor receptor (EGFR) expression. We enrolled 197 patients with stage III CRC who had undergone radical resection and FOLFOX regimen adjuvant chemotherapy. The clinicopathological features and effects of metronomic maintenance therapy with oral capecitabine (daily dose of 850 mg/m², twice daily, on days 1–14 every 3 weeks for 6 months) on survival according to treatment group and EGFR expression were analyzed. By conducting an in vitro cell line study and in vivo study through knockout of the EGFR gene, we analyzed the capacities of cell proliferation and migration. Relapse and survival were significantly more common in the FOLFOX group. Metronomic maintenance therapy was a significantly independent associated factor of relapse and survival as well as a prognostic factor of disease-free survival and overall survival. Significant intergroup differences in survival were only observed in patients with positive EGFR expression. Thus, our findings suggest EGFR expression is a prognostic factor in patients with stage III CRC receiving metronomic maintenance therapy. Analysis of EGFR expression in these patients helps identify potential candidates who may receive the optimal survival benefit from metronomic maintenance therapy.

Prognostic and predictive value of an autophagy-related signature for early relapse in stages I-III colon cancer

We postulated that expression differences of autophagy-related genes are instrumental in stratifying the risk of early relapse after surgery and evaluating the prognosis of patients with stages I-III colon cancer. Therefore, propensity score matching analysis was performed between patients in early relapse group and long-term survival group from GSE39582 test series and internal validation series. Using Cox regression model, a nine-autophagy-related signature (CAPN2, ATG16L2, TP63, SIRT1, RPS6KB1, PEX3, ATG5, UVRAG, NAF1) was established to classify patients into those at high risk of early relapse (high-risk group), and those at low risk of early relapse (low-risk group). Relapse-free survival (RFS) was significantly different between the two groups in test [hazard ratio (HR): 2.019, 95% confidence interval (CI): 1.362-2.992, P < 0.001], internal validation (HR: 2.464, 95% CI: 1.196-5.079, P < 0.001) and another two external validation series (GSE14333-HR: 2.250, 95% CI: 1.227-4.126, P = 0.007; GSE33113-HR: 5.552, 95% CI: 2.098-14.693, P < 0.001). Then, based on RFS, we developed a nomogram, integrating the nine-autophagy-related classifier and four clinicopathological risk factors to evaluate prognosis of stages I-III colon cancer patients. Time-dependent receiver operating curve at 2 years showed that the integrated signature (area under curve = 0.758) had better prognostic accuracy than American Joint Committee on Cancer TNM stage (area under curve = 0.620). In conclusion, we identified and built a nine-autophagy-related signature, a credible approach to early relapse prediction in stages I-III colon cancer patients, which can assist physicians in devising more efficient therapeutic strategies.

Gut butyrate-producing organisms correlate to Placenta Specific 8 protein: Importance to colorectal cancer progression

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Genes from stools have molecular significance with CRC tumorgenesis.

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SCFAs, the metabolites of microbiota, can suppress CRC tumorigenesis.

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Relationship between colonic genes, gut microbiota, or their metabolites is significant.

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Changes of PLAC8 and butyrate-producing organisms were found in stools of CRC patients.

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Butyrate can reduce the CRC formation through regulating PLAC8 expression.

Tumor metastasis or recurrence often occurs in patients with curative resection of colorectal cancer (CRC). Placental-specific 8 (PLAC8), which has increased expression in stool, may be associated with CRC recurrence. Insights into the role of PLAC8 in CRC recurrence and its clinical significance may support to develop strategies for preventing CRC recurrence and deterioration. Clinical tissues, cell and animal models were used to clarify the roles of PLAC8 in CRC tumorigenesis, invasion, and migration. Next-generation sequencing of 16S ribosomal DNA has been used to assess the gut microbiota in stool of CRC patients. We found that PLAC8 was upregulated in tissues from patients with late-stage CRC. In our in vitro studies, PLAC8 was dynamically regulated in mitotic cells. Overexpressed PLAC8 was nucleated at the centrosome during mitosis, and therefore, PLAC8 overexpression might increase cell growth and migration (all p < 0.05). The tumorigenic and invasive effects of PLAC8 on CRC cells were also confirmed in a xenograft mouse model. We further identified reduced levels of two butyrate-producing organisms, Butyricicoccus and Prevotella spp., in stools from CRC patients. We found that butyrate downregulated PLAC8 expression and induced apoptosis in PLAC8-overexpressing cells. Our data suggests that PLAC8 gene and protein expression and dysbiosis of gut microflora, especially in butyrate-producing microorganisms, may be indicators of CRC progression.

Association of Preoperative and Postoperative Serum Carcinoembryonic Antigen and Colon Cancer Outcome

Importance

Guidelines recommend measuring preoperative carcinoembryonic antigen (CEA) in patients with colon cancer. Although persistently elevated CEA after surgery has been associated with increased risk for metastatic disease, prognostic significance of elevated preoperative CEA that normalized after resection is unknown.

Objective

To investigate whether patients with elevated preoperative CEA that normalizes after colon cancer resection have a higher risk of recurrence than patients with normal preoperative CEA.

Design, Setting, and Participants

This retrospective cohort analysis was conducted at a comprehensive cancer center. Consecutive patients with colon cancer who underwent curative resection for stage I to III colon adenocarcinoma at the center from January 2007 to December 2014 were identified.

Exposures

Patients were grouped into 3 cohorts: normal preoperative CEA, elevated preoperative but normalized postoperative CEA, and elevated preoperative and postoperative CEA.

Main Outcomes and Measures

Three-year recurrence-free survival (RFS) and hazard function curves over time were analyzed.

Results

A total of 1027 patients (461 [50.4%] male; median [IQR] age, 64 [53-75] years) were identified. Patients with normal preoperative CEA had 7.4% higher 3-year RFS (n = 715 [89.7%]) than the combined cohorts with elevated preoperative CEA (n = 312 [82.3%]) (P = .01) but had RFS similar to that of patients with normalized postoperative CEA (n = 142 [87.9%]) (P = .86). Patients with elevated postoperative CEA had 14.9% lower RFS (n = 57 [74.5%]) than the combined cohorts with normal postoperative CEA (n = 857 [89.4%]) (P = .001). The hazard function of recurrence for elevated postoperative CEA peaked earlier than for the other cohorts. Multivariate analyses confirmed that elevated postoperative CEA (hazard ratio [HR], 2.0; 95% CI, 1.1-3.5), but not normalized postoperative CEA (HR, 0.77; 95% CI, 0.45-1.30), was independently associated with shorter RFS.

Conclusions and Relevance

Elevated preoperative CEA that normalizes after resection is not an indicator of poor prognosis. Routine measurement of postoperative, rather than preoperative, CEA is warranted. Patients with elevated postoperative CEA are at increased risk for recurrence, especially within the first 12 months after surgery.

The prognostic value of the postoperative serum CEA levels/preoperative serum CEA levels ratio in colorectal cancer patients with high preoperative serum CEA levels

Purpose

This study aimed to assess the prognostic value of the postoperative serum carcinoembryonic antigen (CEA) levels/preoperative serum CEA levels ratio (CEA ratio) in colorectal cancer (CRC) patients with high preoperative serum CEA levels and to identify the optimal prognostic cutoff value.

Patients and methods

The medical records of 187 CRC patients in a single center who underwent surgery between September 2012 and September 2014 were retrospectively reviewed. CEA ratio was defined as the ratio between the postoperative serum CEA and preoperative serum CEA. The optimal cutoff values for the CEA ratio were determined by time-dependent receiver operating characteristic (ROC) curve analyses. The Chi-square test or Fisher’s exact probability test were used to test the correlation between CEA ratio and clinicopathological characteristics. Univariate, multivariate, and subgroup Cox proportional hazards analysis were used to identify independent prognostic factors. Kaplan–Meier method was used for establishing survival curves.

Results

The median follow-up time was 62 months (range 3–88 months). The optimal CEA ratio cutoff value closely related to disease-free survival was 0.295. In the Chi-square test, the CEA ratio was associated with pN stage (p=0.003) and postoperative CEA (p<0.001). In the multivariate analysis, the CEA ratio was an independent prognostic factor for disease-free survival (p=0.003, HR 2.300 [95% CI: 1.326–3.988]) and cancer-special survival (p=0.003, HR 2.525 [95% CI: 1.381–4.614]). The CEA ratio reflected the prognosis of CRC patients more accurately than postoperative CEA levels alone, and the CEA ratio of 0.295 was more likely to reflect the prognosis than other cutoff values.

Conclusion

The CEA ratio is a simple and useful tool for further forecasting the prognosis of CRC patients with high preoperative CEA levels and may help develop strategies for the postoperative treatment of CRC patients.

Predictive Value of the Number of Harvested Lymph Nodes and Cut-Off for Lymph Node Ratio in the Prognosis of Stage II and III Colorectal Cancer Patients

Purpose/aim: The appropriate staging of colorectal cancer requires at least 12 lymph nodes to be sampled. We evaluated whether lymph node sampling (LNS) and lymph node ratio (LNR) can predict the prognosis of stage II-III patients.

MATERIALS AND METHODS

This is a retrospective study on 432 patients classified in LNS ≥12 and LNS <12. Disease-free survival (DFS) was computed using the Kaplan-Meier method. We stratified stage III patients into 4 quartiles base on LNR values. To determine the optimal LNR cut-off, receiver operating characteristic (ROC) curve analysis was performed.

RESULTS

There was a positive association between the number of lymph node sampled and the number of metastatic lymph nodes (p < 0.01). Among stage II patients, the DFS was 81% for LNS ≥ 12 and 72% for LNS < 12 (p = 0.158). Among stage III patients, the DFS was 58% (p < 0.001). We found a significant association between LNR quartiles and relapse in stage III patients but only in the LNS ≥ 12 group. ROC curve analysis indicated an ideal LNR cut-off value at 0.194 (sensitivity 65% and specificity 61%). The DFS of patients with LNR below 0.194 was 71%, and that of patients with LNR above 0.194 was 45% (log-rank test, p < 0.001). In the patients with LNS ≥ 12, the cut-off of 0.257 could predict recurrence (specificity 86%).

CONCLUSIONS

Stage II patients with LNS < 12 tend to have shorter DFS than stage II patients with LNS ≥ 12. In stage III patients, an appropriate LNR cut-off is a better prognostic predictor than LNR quartile, especially in patients with LNS ≥ 12.

Incidence of extramural venous invasion in colorectal carcinoma as determined at the invasive tumor front and its prognostic impact

Extramural venous invasion (EMVI) is prognostic for colorectal cancer; however, veins are only detected partially by normal perpendicular preparation. Therefore, reported findings are conflicting and standardization is required. A total of 239 resection specimens were examined by tangential preparation of the extramural veins at the invasive tumor front. Average follow-up was 39 months. The relationship of EMVI to metachronous hematogenic metastasis (MHM) was evaluated. With this method, a high prevalence of EMVI beginning in stage II is apparent. In stage I, 66% of patients with EMVI developed MHM; in stage II, 25%; and in stage III, 49%. In stage III, the number of tumor-invaded veins is crucial. In the absence of detection of EMVI, MHM occurred in 1 of 29 patients in stage II and in 2 of 13 patients in early stage III. By tangential sectioning at the invasive tumor front, we found a high incidence of EMVI beginning in stage II, which increases with tumor stage. Especially in stages II and III, the correct determination of absent EMVI has a high negative predictive value for MHM. In stage I, EMVI defines a patient group with increased risk for MHM. The quantification of EMVI is an important issue for standardization.

The impacts of surgery of the primary cancer and radiotherapy on the survival of patients with metastatic rectal cancer

The role of surgery of the primary cancer and radiation in metastatic colorectal cancer (mCRC) is still controversial currently, and evidence implied that colon cancer (CC) and rectal cancer (RC) should be treated with difference. Hence we focused on metastatic rectal cancer (mRC) solely to compare the cancer cause-specific survival (CSS) of patients receiving varied treatments of the primary cancer: no treatment, surgery only, radiation only, and surgery plus radiation, based on the records of the Surveillance, Epidemiology, and End Results (SEER) database. A total of 8669 patients were included. Results demonstrated that the 2-year CSS was 28.1% for no treatment group, 30.7% for only radiation group, 50.2% for only surgery group, and 66.5% for surgery plus radiation group, reaching statistical difference (P < 0.001). Furthermore, the CSSs of mRC patients in the surgery group were similar regardless of resection ranges (P = 0.44). Besides, we analyzed the prognostic factors for mRC and found carcinoembryonic antigen (CEA) level, metastasis (M) stage, Tumor (T) stage, tumor size, differentiate grade, age and marital status should be taken into consideration when estimating the prognosis. Particularly, patients with normal CEA level or M1a stage showed a significant survival advantage. Overall, present study suggested that surgery of the primary cancer and radiation might help to improve the survival of mRC patients, especially when both treatments were conducted. Our results may assist clinicians to make better treatment strategy for patients with mRC.

Stromal Expression of Vimentin Predicts the Clinical Outcome of Stage II Colorectal Cancer for High-Risk Patients

Background

Increased expression of vimentin in tissue samples from patients with colorectal cancer (CRC) has been previously demonstrated, but its prognostic significance remains controversial, and the clinical significance for patients with stage II CRC is still unknown. The aim of this study was to evaluate the expression of vimentin in CRC and its potential prognostic significance.

Material/Methods

We analyzed vimentin expression in 203 CRC tissue samples from patients with stage II cancer using immunohistochemistry, and correlated the findings with clinicopathological patient features. CRC-specific survival (CSS) and disease-free survival (DFS) were analyzed using the Kaplan-Meier method. Univariate and multivariate analysis was performed using the Cox proportional hazards method for survival.

Results

Vimentin expression was significantly correlated only with tumor (T) stage (p=0.024). Kaplan-Meier survival analysis indicated that vimentin expression could stratify the CSS and DFS of patients with stage II CRC at high risk (p=0.029, p=0.042, respectively), but not those of low-risk stage II patients (p=0.208, p=0.361, respectively). Univariate and multivariate analysis further revealed that stromal vimentin expression is an independent prognostic factor for CSS and DFS of high-risk stage II patients (p=0.043, p=0.022, respectively). Moreover, high-risk stage II patients with low stromal vimentin expression benefitted more from standard adjuvant chemotherapy than those with high stromal vimentin expression (CSS: p=0.012 vs. p=0.407; DFS: p=0.017 vs. p=0.420).

Conclusions

Our study suggests that stromal vimentin expression is a promising indicator for survival prediction and adjuvant chemotherapy response in patients with stage II CRC with high-risk factors for recurrence.

Development of a deregulating microRNA panel for the detection of early relapse in postoperative colorectal cancer patients

Background

Colorectal cancer (CRC) is the third leading cause of cancer mortality worldwide and is associated with high recurrence and mortality, despite recent advancements in therapeutic strategies. MicroRNA (miR) deregulation is associated with CRC development and recurrence; therefore, miRs may be reliable biomarkers for detecting early relapse postoperatively.

Methods

In this study ten candidates were identified using miR arrays: miR-7, miR-31, miR-93, miR-141, miR-195, miR-375, miR-429, miR-494, miR-650, and let-7b. Substantial differences were observed in their expression levels between early relapsed (recurrences within 12 months after surgery) and non-early relapsed CRC patients. The validation study, including 50 early relapsed and 54 non-early relapsed patients, confirmed miR expression alterations in cancer tissue samples.

Results

Using a miR real-time quantitative polymerase chain reaction (RT-qPCR), we observed that expression levels of miR-93, miR-195, and let-7b were significantly decreased, whereas those of miR-7, miR-141 and miR-494 showed increases that were more significant in the CRC tissue samples from the early relapsed patients than in those from the non-early relapsed patients. Disease-free survival and overall survival were significantly worse in the high miR-7, miR-141, and miR-494 expression subgroups and the low miR-93 and miR-195 expression subgroups (all P < 0.05). A panel of 6 miRs (miR-7, miR-93, miR-195, miR-141, miR-494, and let-7b), at a cut-off value of 2 deregulated miRs, distinguished early relapsed CRC from non-early relapsed CRC, with a sensitivity of 76.6 % and a specificity of 71.4 %. By combining this 6-miRs panel with 6 clinicopathologic factors, at a cut-off value of 4, distinguished early relapsed CRC from non-early relapsed CRC, with a sensitivity of 89.4 % and a specificity of 88.9 %.

Conclusions

This study showed that the developed miR panel has the potential to improve predicting early relapse in CRC patients.