Tumor budding for predicting prognosis of resected rectum cancer after neoadjuvant treatment

Prognostic impact of tumor budding in rectal cancer after neoadjuvant therapy: a systematic review and meta-analysis

BACKGROUND

Tumor budding (TB) is a negative prognostic factor in colorectal cancer; however, its prognostic impact following neoadjuvant therapy for patients with rectal cancer remains unclear. This study aims to assess the prognostic impact of TB and the correlation between TB and other pathological features in patients with rectal cancer after neoadjuvant therapy.

METHODS

A comprehensive search of PubMed, Embase, Cochrane, Scopus, CNKI, Wanfang, and ClinicalKey databases was conducted for studies on the prognosis of TB in rectal cancer after neoadjuvant therapy from the inception of the databases to January 2023, and the final literature included was determined using predefined criteria. Quality assessment of the studies included, extraction of general and prognostic information from them, and meta-analyses were carried out progressively.

RESULTS

A total of 11 studies were included, and the results of the meta-analysis showed that high-grade tumor budding (TB-1) increased the risk of poor 5-year disease-free survival (HR = 1.75, 95% CI 1.38-2.22, P < 0.00001), 5-year overall survival (HR = 1.77, 95% CI 1.21-2.59, P = 0.003), local recurrence (OR = 4.15, 95% CI 1.47-11.75, P = 0.007), and distant metastasis (OR = 5.36, 95% CI 2.51-11.44, P < 0.0001) in patients with rectal cancer after neoadjuvant therapy. TB-1 was significantly associated with poor differentiation and lymphatic, perineural, and venous invasion.

CONCLUSION

Tumor budding is significantly correlated with unfavorable prognosis and poor pathological characteristics following neoadjuvant therapy for rectal cancer. We anticipate more high-quality, prospective studies in the future to confirm our findings.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022377564.

Bioinformatics analysis of markers based on m6A related to prognosis combined with immune invasion of rectal adenocarcinoma

BACKGROUND

Colorectal cancer (CRC) is a common form of cancer, with rectal cancer accounting for approximately one-third of all cases. Among rectal cancers, 95% are classified as rectal adenocarcinoma (READ). Emerging evidence suggests that long noncoding RNAs (lncRNAs) play a significant role in the development and progression of various cancers. In our study, we aimed to identify differentially expressed lncRNAs potentially associated with m6A and establish a risk assessment model to predict clinical outcomes for READ patients.

METHODS

The READ dataset from the TCGA database was utilized in this study to synergistically and logically integrate m6A and lncRNA, while employing bioinformatics technology for the identification of suitable biomarkers. A risk prediction model comprising m6A-associated lncRNAs was constructed to investigate the prognostic, diagnostic, and biological functional relevance of these m6A-related lncRNAs.

RESULTS

Our research builds a composed of three related to m6A lncRNA rectal gland cancer prognosis model, and the model has been proved in the multi-dimensional can serve as the potential of the prognosis of rectal gland cancer biomarkers. Our study constructed a prognostic model of rectal adenocarcinoma consisting of three related m6A lncRNAs: linc00702, ac106900.1 and al583785.1.

CONCLUSION

The model has been validated as a potential prognostic biomarker for rectal cancer in multiple dimensions, aiming to provide clinicians with an indicator to assess the duration of straight adenocarcinoma. This enables early detection of rectal cancer and offers a promising target for immunotherapy.

Preoperative prediction of tumor budding in rectal cancer using multiple machine learning algorithms based on MRI T2WI radiomics

Objective

This study aimed to explore the radiomics model based on magnetic resonance imaging (MRI) T2WI and compare the value of different machine algorithms in preoperatively predicting tumor budding (TB) grading in rectal cancer.

Methods

A retrospective study was conducted on 266 patients with preoperative rectal MRI examinations, who underwent complete surgical resection and confirmed pathological diagnosis of rectal cancer. Among them, patients from Qingdao West Coast Hospital were assigned as the training group (n=172), while patients from other hospitals were assigned as the external validation group (n=94). Regions of interest (ROIs) were delineated, and image features were extracted and dimensionally reduced using the Least Absolute Shrinkage and Selection Operator (LASSO). Eight machine algorithms were used to construct the models, and the diagnostic performance of the models was evaluated and compared using receiver operating characteristic (ROC) curves and the area under the curve (AUC), as well as clinical utility assessment using decision curve analysis (DCA).

Results

A total of 1197 features were extracted, and after feature selection and dimension reduction, 11 image features related to TB grading were obtained. Among the eight algorithm models, the support vector machine (SVM) algorithm achieved the best diagnostic performance, with accuracy, sensitivity, and specificity of 0.826, 0.949, and 0.723 in the training group, and 0.713, 0.579, and 0.804 in the validation group, respectively. DCA demonstrated the clinical utility of this radiomics model.

Conclusion

The radiomics model based on MR T2WI can provide an effective and noninvasive method for preoperative TB grading assessment in patients with rectal cancer.

Quality assessment of rectal cancer surgery: How are we doing?

INTRODUCTION

Surgery remains a cornerstone in the treatment of rectal cancer. Optimal surgical resection implies respect for carcinologic principles. The best way to evaluate a good quality of resection requires certainly an exhaustive evaluation of the surgical specimen by the surgeon and the pathologist.

AIM

To assess the quality of resected rectal cancers.

METHODS

This study included patients operated on for rectal malignant epithelial tumors, between January 1st, 2015 and December 31st, 2020, in the general surgery department B at Charles Nicolle's Hospital in Tunis. Data relevant to the pathologic examination were recorded. We performed a descriptive study and an analytic bivariate study comparing the two groups "number of lymph nodes harvested less than 12" versus "number of lymph nodes harvested higher than or equal to 12".

RESULTS

Neoadjuvant therapy was performed in 39 patients (79%). Anterior resection (AR) was performed in 43 patients (43%) and abdominoperineal resection (APR) was performed in 11 patients (20%). There were no invaded margins. The mean distal surgical margin was 3±1.4 cm. Mesorectum was complete in 38 surgical specimens (70%). The median number of lymph nodes harvested was 14. Resection was considered R0 in 47 patients (87%). In bivariate analysis, there was no difference between the "number of harvested lymph nodes <12" and the "number of harvested lymph nodes ≥ 12"groups for the variables: laparotomy, laparoscopic approach, conversion to laparotomy and chemoradiotherapy.

CONCLUSION

Quality of surgical resection of rectal cancer in our department was in accordance with recommendations.

Natural podophyllotoxin analog 4DPG attenuates EMT and colorectal cancer progression via activation of checkpoint kinase 2

Epithelial–mesenchymal transition (EMT) is critical for the metastatic dissemination of cancer cells and contributes to drug resistance. In this study, we observed that epithelial colorectal cancer (CRC) cells transiently exposed to 5-fluorouracil (5-FU) (a chemotherapeutic drug for CRC) as well as 5-FU-resistant cells (5-FU-R) develop EMT characters as evidenced by activation of Vimentin and augmented invasive properties. On the other hand, 4DPG (4′-demethyl-deoxypodophyllotoxin glucoside), a natural podophyllotoxin analog attenuates EMT and invadopodia formation abilities of HCT-116/5-FU-R and SW-620/5-FU-R cells. Treatment with 4DPG restrains Vimentin phosphorylation (Ser38) in 5-FU-R cells, along with downregulation of mesenchymal markers Twist1 and MMP-2 while augmenting the expression of epithelial markers E-cadherin and TIMP-1. Moreover, 4DPG boosts the tumor-suppressor protein, checkpoint kinase 2 (Chk2) via phosphorylation at Thr68 in a dose-dependent manner in 5-FU-R cells. Mechanistically, SiRNA-mediated silencing of Chk2, as well as treatment with Chk2-specific small-molecule inhibitor (PV1019), divulges that 4DPG represses Vimentin activation in a Chk2-dependent manner. Furthermore, immunoprecipitation analysis unveiled that 4DPG prevents complex formation between Vimentin and p53 resulting in the rescue of p53 and its nuclear localization in aggressive 5-FU-R cells. In addition, 4DPG confers suitable pharmacokinetic properties and strongly abrogates tumor growth, polyps formation, and lung metastasis in an orthotopic rat colorectal carcinoma model. In conclusion, our findings demonstrate 4DPG as a targeted antitumor/anti-metastatic pharmacological lead compound to circumvent EMT-associated drug resistance and suggest its clinical benefits for the treatment of aggressive cancers.

Retrospective survival analysis of stage II-III rectal cancer: tumour regression grade, grading and lymphovascular invasion are the only predictors

BACKGROUND

Tumour regression grade is gaining interest as a prognostic factor of patients undergoing neoadjuvant chemoradiotherapy and surgery for locally advanced rectal cancer.

METHODS

A series of 68 consecutive patients with locally advanced rectal cancer treated by neoadjuvant chemoradiotherapy and surgery between 2010 and 2016 was retrospectively studied. The impact on disease-free survival (DFS) and overall survival (OS) of several criteria was analysed. Univariate analysis was performed through Kaplan-Meier statistics. Multivariate analysis was performed through Cox regression model. Using criteria found to be related to long-term outcomes, a predictive model of patient's OS was calculated.

RESULTS

Poor tumour regression grade - TRG3 (P = 0.010), poor grading - G3 (P = 0.001) and lymphovascular invasion (LVI; P = 0.030) were associated with short OS at univariate analysis. OS was associated with TRG3 and G3 at multivariate analysis (P = 0.016 and P = 0.027, respectively). DFS was associated with LVI (P = 0.001), G3 tumours (P = 0.046) and TRG3 (P = 0.045) at univariate analysis. At multivariate analysis, only LVI was associated with DFS (P = 0.041). A score, pondering the impact of three parameters (2 points for TRG3, 2 for G3 and 1 for LVI), was created and resulted to predict patient OS (P = 0.008), ranging from 94.5 months (score = 0-1) to 32 months (score = 3-5).

CONCLUSION

TRG3 and G3 were associated with poor OS, and LVI was the most significant predictor of DFS. An easy-to-use score may allow for a more accurate prediction of OS.

Tumor budding outperforms ypT and ypN classification in predicting outcome of rectal cancer after neoadjuvant chemoradiotherapy

Background

Budding is a complementary prognostic factor for colorectal cancer. In this study, we aimed to clarify the role of tumor budding in rectal cancer patients after preoperative chemoradiotherapy.

Methods

A total of 124 patients with rectal cancer treated with neoadjuvant chemoradiotherapy and consecutive surgery were included. Surgical specimens were evaluated for budding and routine clinicopathological features. Budding was evaluated on hematoxylin and eosin (H&E)-stained slides and by cytokeratin immunohistochemical (IHC) staining.

Results

A budding rate of 36.9% (n = 38) by H&E and 55.6% (n = 55) by IHC was observed. Budding was significantly associated with a high ypT and ypN status, poor differentiation, and low degrees of tumor regression. Moreover, budding was strongly predictive of a worse patient outcome, as measured by tumor recurrence or death. In multivariate analyses, budding remained the only significant parameter for overall survival and was even superior to the ypT and ypN status (budding in H&E: hazard ratio (HR) 2.72, 95% confidence interval (95% CI) 1.15–6.44, p = 0.023; budding in IHC: HR 5.19, 95% CI 1.62–16.61, p = 0.006).

Conclusion

Budding is a strong prognostic predictor of survival in rectal cancer patients after neoadjuvant therapy. A standardized evaluation of tumor budding after neoadjuvant therapy may thus aid in risk stratification and guide the clinical management of patients with rectal cancer. Immunostaining can help to enhance the diagnostic accuracy and prognostic significance.