Defining stage III disease in colorectal cancer-aspects on treatment and evaluation of survival

Predicting treatment failure in stage III colon cancer patients after radical surgery

Purpose

The aim to assess treatment failure in patients with stage III colon cancer who underwent radical surgery and was analyzed using the nomogram.

Methods

Clinical factors and survival outcomes for stage III colon cancer patients registered in the SEER database from 2018 to 2019 were analyzed, with patients split into training and testing cohorts (7:3 ratio). A total of 360 patients from the First Affiliated Hospital of Longyan served as an external validation cohort. Independent predictors of treatment failure were identified using logistic regression analyses. The nomograms was evaluated by concordance index (C-index), calibration curves, and the area under the curve (AUC), decision curve analysis (DCA) and clinical impact curves (CIC) assessed the clinical utility of nomograms versus TNM staging.

Results

The study included 4,115 patients with stage III colon cancer. Multivariate logistic analysis age, tumor site, pT stage, pN stage, chemotherapy, pretreatment CEA levels, number of harvested lymph nodes, perineural invasion and marital status were identified as independent risk factors for treatment failure. The C-indices for the training and testing sets were 0.853 and 0.841. Validation by ROC and calibration curves confirmed the stability and reliability of the model. DCA showed that the net clinical effect of the histogram was superior to that of the TNM staging system, while CIC highlighted the potentially large clinical impact of the model.

Conclusions

The developed Nomogram provides a powerful and accurate tool for clinicians to assess the risk of treatment failure after radical surgery in patients with stage III colon cancer.

Scatter patterns in lymph node metastases as a novel prognostic indicator in patients with stage III/N2 colorectal cancer

To classify patients with stage III/N2 colorectal cancer into high- and low-risk groups for recurrence, the present study compared clinicopathological features by immunohistochemical staining. The single-center analysis included 53/668 patients (7.9%) with stage III/N2 colorectal cancer who underwent radical resection between January 2006 and December 2014. The present study examined cancer cell distribution in metastatic lymph nodes and classified patients into a group with circumferential localization patterns like a cystic mass (CLP) and a group with scatter patterns like fireworks (SPF). Subsequently, 5-year relapse-free survival (5Y-RFS) and 5-year overall survival (5Y-OS) rates were compared and the histological type (differentiation degree) of the primary adenocarcinoma was included. The CLP group included 16 patients (30.2%) and the SPF group included 37 patients (69.8%). The 5Y-RFS rates in these groups were 75.0 vs. 37.8%, respectively (P=0.021), and the 5Y-OS rates were 81.3 vs. 48.6% (P=0.033). Patient clinicopathological characteristics exhibited no significant differences between groups. The adenocarcinoma was well differentiated in 14 patients (Well; 26.4%) and moderately (Mod; n=37) or poorly (Por; n=2) differentiated in 39 patients (Mod+Por; 73.6%). Patients were further classified into four groups: Well/CLP (n=6), Well/SPF (n=8), Mod+Por/CLP (n=10) and Mod+Por/SPF (n=29). For Well/CLP vs. Well/SPF, the 5Y-RFS rates were 66.7 vs. 25.0%, respectively (P=0.293), and for Mod+Por/CLP vs. Mod+Por/SPF (80.0 vs. 41.4%; P=0.052), the respective values for 5Y-OS were 66.7 vs. 50.0% (P=0.552) and 90.0 vs. 48.3% (P=0.059). Based on the aforementioned results, the CLP group was considered a low-risk group for recurrence with a relatively good prognosis; however, the SPF group was considered a high-risk group for recurrence with a poor prognosis, suggesting a need for more potent multi-combination chemotherapy in these patients from the early postoperative period.

Comparison of two novel staging systems with the TNM system in predicting stage III colon cancer survival

BACKGROUND AND OBJECTIVES

Adaptations of the TNM staging system that incorporate the Lymph Node Ratio (LNR) have been proposed for stage III colon cancer. This study compared the concordance of two novel staging systems and the TNM system with observed survival outcomes in stage III patients.

METHODS

A review of patients who underwent surgery for stage III colon cancer between January 2002 and April 2015 at a tertiary care centre was performed. The Kaplan-Meier method was used to estimate the 5-year overall (OS) and disease free survival (DFS) rates, and the concordance probability was calculated to evaluate the discriminatory power of the staging systems.

RESULTS

Two hundred and sixty-one patients were identified. For TNM stages IIIA, IIIB, and IIIC, 5-year OS was 83.4%, 67.6%, and 38.3%, respectively (P < 0.001). All three staging systems were independently predictive of OS and DFS (P < 0.001). However, the novel staging system by Sugimoto et al¹⁸ was the most favourable prognostic tool, with a concordance of 0.646 for DFS and 0.659 for OS.

CONCLUSIONS

The novel staging system by Sugimoto et al¹⁸ was superior to the TNM system. Incorporating LNR into staging models for node positive colon cancers may improve survival information available to patients and potentially aid treatment decisions.

Thymidine Phosphorylase Gene Expression in Stage III Colorectal Cancer

BACKGROUND

The thymidine phosphorylase (TP) enzyme has several tumor-promoting functions. The aim of this study was to explore TP gene expression in relation to clinical and histopathological data obtained from patients with stage III colorectal cancer.

METHODS AND RESULTS

TP gene expression was analyzed by real-time quantitative PCR in tumor and mucosa samples from 254 patients. TP gene expression in tumors correlated with lymph node staging, with higher expression relating to a higher number of positive nodes and a worse N-stage. Higher TP expression was also associated with a worse histological tumor grade. Patients with rectal cancer had significantly higher TP expression in mucosa and tumors compared with patients having colon cancer.

CONCLUSION

Higher intratumoral TP expression appears to be related to a worse N stage, and thus, with a worse prognosis. TP gene expression measured in a preoperative biopsy could be of interest in preoperative staging.