Changes in serum uric acid, serum uric acid/serum creatinine ratio, and gamma-glutamyltransferase might predict the efficacy of neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer

PURPOSE

The purpose of this study was to investigate the predictive value of changes in serum uric acid (SUA), the ratio of serum uric acid to serum creatinine (SUA/SCr), and serum gamma-glutamyltransferase (GGT) from before to after therapy in patients with locally advanced rectal cancer (LARC).

METHODS

Data from 114 LARC patients from January 2016 to December 2021 were included in this retrospective study. All patients received neoadjuvant chemoradiotherapy (nCRT) and total mesorectal excision (TME). The change in SUA was calculated as a ratio: (SUA level after nCRT-SUA level before nCRT)/SUA level before nCRT. The change ratios of SUA/SCr and GGT were calculated in the same way. The efficacy of nCRT was evaluated by magnetic resonance (MR) and postoperative pathological response. A nonlinear model was used to evaluate whether the change ratios of SUA, SUA/SCr, and GGT were associated with the efficacy of nCRT. The predictive power of the change ratios of SUA, SUA/SCr, and GGT was assessed by receiver operating characteristic (ROC) curves. Univariate and multivariate Cox regression analyses were employed to measure the associations between disease-free survival (DFS) and other predictive indicators. The Kaplan-Meier method was used to further compare DFS between groups.

RESULTS

The nonlinear model indicated that the change ratios of SUA, SUA/SCr, and GGT were associated with the efficacy of nCRT. The change ratios of SUA, SUA/SCr, and GGT were used to predict the area under the ROC curve of efficacy for nCRT (0.95, 0.91-0.99), which was better than the prediction by the change ratio of SUA (0.94, 0.89-0.99), SUA/SCr (0.90, 0.84-0.96), or GGT alone (0.86, 0.79-0.93; p < 0.05). The optimal cut-off values of SUA, SUA/SCr, and GGT change were 0.02, 0.01, and 0.04, respectively. The Kaplan-Meier method indicated that patients with SUA, SUA/SCr, or GGT changes greater than the cut-off values had shorter DFS (p < 0.05).

CONCLUSION

Change ratios of SUA, SUA/SCr, or GGT greater than the cut-off values implied a risk of poor pathological response after nCRT and shorter DFS in LARC patients.

Assessing circulating tumour DNA (ctDNA) as a prognostic biomarker in locally advanced rectal cancer: a systematic review and meta-analysis

INTRODUCTION

Circulating tumour DNA (ctDNA) has emerged as a promising biomarker in various cancer types, including locally advanced rectal cancer (LARC), offering potential insights into disease progression, treatment response and recurrence. This review aims to comprehensively evaluate the utility of ctDNA as a prognostic biomarker in LARC.

METHODS

PubMed, EMBASE and Web of Science were searched as part of our review. Studies investigating the utility of ctDNA in locally advanced rectal cancer (LARC) were assessed for eligibility. Quality assessment of included studies was performed using the Newcastle Ottawa Scale (NOS) risk of bias tool. Outcomes extracted included basic participant characteristics, ctDNA details and survival data. A meta-analysis was performed on eligible studies to determine pooled recurrence-free survival (RFS).

RESULTS

Twenty-two studies involving 1676 participants were included in our analysis. Methodological quality categorised by the Newcastle Ottawa Scale was generally satisfactory across included studies. ctDNA detected at various time intervals was generally associated with poor outcomes across included studies. Meta-analysis demonstrated a pooled hazard ratio of 8.87 (95% CI 4.91-16.03) and 15.15 (95% CI 8.21-27.95), indicating an increased risk of recurrence with ctDNA positivity in the post-neoadjuvant and post-operative periods respectively.

CONCLUSION

Our systematic review provides evidence supporting the prognostic utility of ctDNA in patients with LARC, particularly in identifying patients at higher risk of disease recurrence in the post-neoadjuvant and post-operative periods.

The prognostic role of the change in albumin-derived neutrophil-to-lymphocyte ratio during neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer

The prognosis of patients with locally advanced rectal cancer (LARC) has improved with the adoption of a multidisciplinary treatment approach combining neoadjuvant chemoradiotherapy (nCRT) and total mesorectal excision (TME). Developing real-time, sensitive biomarkers to monitor systemic changes during nCRT is of paramount importance. Although the association between albumin-derived neutrophil-to-lymphocyte ratio (Alb-dNLR) and prognosis in various cancers is established, its prognostic value in LARC patients undergoing nCRT is not well-studied. This study enrolled a cohort of 618 LARC patients, stratifying them into two groups according to their change in Alb-dNLR (∆Alb-dNLR) values, using an optimal cut-off point: a low ∆Alb-dNLR group (≤ 0.90) and a high ∆Alb-dNLR group (> 0.90). The prognostic significance of ∆Alb-dNLR was evaluated using a Cox proportional hazards model. The 5-year overall survival (OS) rates were 75.2% in the low ∆Alb-dNLR group (≤ 0.90) and 85.9% in the high ∆Alb-dNLR group (>0.90) (P < 0.001). The 5-year disease-free survival (DFS) rates were 71.2% and 80.6%, respectively (P = 0.016). Multivariate analyses demonstrated that both ∆Alb-dNLR and pre-Alb-dNLR were independent prognostic factors for OS (P ≤ 0.001), while ∆Alb-dNLR was demonstrated as an independent prognostic factor for DFS (P = 0.016). A predictive nomogram, incorporating the ∆Alb-dNLR subgroup, demonstrated enhanced performance (concordance index [C-index] of 0.720 for OS and 0.690 for DFS) compared to the pre-treatment Alb-dNLR subgroup (C-index of 0.700 for OS and of 0.680 for DFS). Therefore, ∆Alb-dNLR shows significant potential as a usable and prognostic biomarker for predicting OS and DFS in LARC patients undergoing nCRT.

The association of preoperative hematologic parameters with short-term clinical outcomes in rectal cancer: A feature importance analysis

BACKGROUND

Various hematologic parameters have been proposed as prognostic factors in rectal cancer management, but data are conflicting and unclear. This study is designed to investigate the prognostic factor capability of preoperative hematologic parameters with postoperative morbidities and mortality in rectal cancer patients undergoing curative resection.

METHODS

All 200 consecutive rectal cancer patients diagnosed at Ghaem University Hospital from 2017 to 2022 were retrospectively evaluated. The receiver operating characteristic (ROC) curves and machine learning (ML) algorithms of Random Forest, Recursive Feature Elimination, simulated annealing, Support Vector Machine, Decision Tree, and eXtreme Gradient Boosting were administered to investigate the role of preoperative hematologic parameters accompanied by baseline characteristics on three clinical outcomes including surgical infectious complications, recurrence, and death.

RESULTS

The frequency of infectious complications was correlated with the surgical procedure, while tumor recurrence was significantly influenced by T stage and N stage. In terms of mortality, alongside T and N stage, the status of resection margin involvement was significantly correlated. Based on the ROC analysis, the NLR >2.69, MPV ≤9 fL, and PDW ≤10.5 fL were more classified patients to mortality status. Likewise, the PLT >220 109/L, MPV ≤9 fL, PDW ≤10.4 fL, and PLR >13.6 were correlated with recurrence. However, all factors examined in this study were not significant classifiers for the outcome of surgical infectious complications. The results of ML algorithms were also in line with ROC analysis.

CONCLUSION

According to the results of both ROC analysis and ML models, preoperative hematologic parameters are considerable prognostic factors of postoperative outcomes in rectal cancer patients, and are recommended to be monitored by clinicians to prevent unfavorable outcomes.

IFN-Type-I Response and Systemic Immunity in Rectal Adenocarcinoma Patients Treated with Conventional or Hypofractionated Neoadjuvant Radiotherapy

The IFN-type-I pathway is involved in radiotherapy (RT)-mediated immune responses. Large RT fractions have been suggested to potently induce this pathway. Neoadjuvant hypofractionated short-course (scRT) and conventional long-course (lcRT) RT applied for the treatment of locally advanced rectal adenocarcinoma patients provides a unique model to address the immuno-stimulatory properties of RT on a systemic level. We prospectively analyzed the IFNβ plasma levels and lymphocyte counts (LCs) of rectal adenocarcinoma patients before and after treatment with scRT (n = 22) and lcRT (n = 40). Flow cytometry was conducted to assess the effects on lymphocytic subpopulations in a subset of 20 patients. A statistically significant increase in the post-RT IFNβ plasma levels was noted in patients undergoing scRT (p = 0.004). Improved pathological tumor regression was associated with elevated post-RT IFNβ levels (p = 0.003). Although all patients experienced substantial lymphopenia after treatment, the post-RT LC of patients treated with scRT were significantly higher compared to lcRT (p = 0.001). Patients undergoing scRT displayed significantly lower percentages of regulatory CD4+/CD25+ T-cells after therapy (p = 0.02). scRT enables effective stimulation of the IFN-type-I pathway on a systemic level and confers decreased lymphocytic cytotoxicity and limited regulatory T-cell activation compared to lcRT, supporting its increasing role in immuno-RT trials.

Combined DNA Analysis from Stool and Blood Samples Improves Tumor Tracking and Assessment of Clonal Heterogeneity in Localized Rectal Cancer Patients

Objectives: In this study, stool samples were evaluated for tumor mutation analysis via a targeted next generation sequencing (NGS) approach in a small patient cohort suffering from localized rectal cancer. Introduction: Colorectal cancer (CRC) causes the second highest cancer-related death rate worldwide. Thus, improvements in disease assessment and monitoring that may facilitate treatment allocation and allow organ-sparing "watch-and-wait" treatment strategies are highly relevant for a significant number of CRC patients. Methods: Stool-based results were compared with mutation profiles derived from liquid biopsies and the gold standard procedure of tumor biopsy from the same patients. A workflow was established that enables the detection of de-novo tumor mutations in stool samples of CRC patients via ultra-sensitive cell-free tumor DNA target enrichment. Results: Notably, only a 19% overall concordance was found in mutational profiles across the compared sample specimens of stool, tumor, and liquid biopsies. Conclusion: Based on these results, the analysis of stool and liquid biopsy samples can provide important additional information on tumor heterogeneity and potentially on the assessment of minimal residual disease and clonal tumor evolution.

Prognostic Significance of Lymphocyte-to-Monocyte and Platelet-to-Lymphocyte Ratio in Rectal Cancer: A Systematic Review, Meta-analysis, and Meta-regression

BACKGROUND

The low lymphocyte-to-monocyte ratio and high platelet-to-lymphocyte ratio have been reported to be poor prognostic indicators in various solid tumors, but the prognostic significance in rectal cancer remains controversial.

OBJECTIVES

We sought to determine the prognostic value of the lymphocyte-to-monocyte ratio and the platelet-to-lymphocyte ratio following curative-intent surgery for rectal cancer.

DATA SOURCES

Following PRISMA guidelines (PROSPERO, ID: CRD42020190880), PubMed and Embase databases were searched through January 2021 including 3 other registered medical databases.

STUDY SELECTION

Studies evaluating the impact of pretreatment lymphocyte-to-monocyte ratio and platelet-to-lymphocyte ratio on overall or disease-free survival in patients undergoing curative rectal cancer resection were selected.

MAIN OUTCOMES MEASURES

The main outcome measures were overall and disease-free survival.

RESULTS

A total of 23 studies (6683 patients) were included; lymphocyte-to-monocyte ratio and platelet-to-lymphocyte ratio were evaluated in 14 and 16 studies. A low lymphocyte-to-monocyte ratio was associated with poorer overall survival (HR, 1.57; 95% CI, 1.29-1.90; p < 0.001) and disease-free survival (HR, 1.29; 95% CI, 1.13-1.46; p < 0.001). However, when the analysis was limited to patients treated with surgery alone or to those with stage I to III tumors, lymphocyte-to-monocyte ratio was not a predictor of overall survival and disease-free survival. The platelet-to-lymphocyte ratio did not predict for overall or disease-free survival, regardless of the treatment modality, studied population, tumor stage, or cutoff value. Finally, a low lymphocyte-to-monocyte ratio, but not a high platelet-to-lymphocyte ratio, was inversely correlated with complete pathologic response rate.

LIMITATIONS

The retrospective nature of most included studies was a limitation.

CONCLUSIONS

Pretreatment lymphocyte-to-monocyte ratio, but not platelet-to-lymphocyte ratio, correlates with tumor response to neoadjuvant chemoradiotherapy and poorer prognosis after curative-intent surgery for rectal cancer, and it potentially represents a simple and reliable biomarker that could help optimize individualized clinical decision-making in high-risk patients.

REGISTRATION

https://www.crd.york.ac.uk/prospero/; ID: CRD42020190880.

Serum apolipoprotein B to apolipoprotein A-I ratio is an independent predictor of liver metastasis from locally advanced rectal cancer in patients receiving neoadjuvant chemoradiotherapy plus surgery

BACKGROUND

The ratio of serum apolipoprotein B (apoB) to apolipoprotein A-I (apoAI) had been reported as a prognostic factor in colorectal cancer. This retrospective study aimed to assess the implication of apoB-to-apoAI ratio in predicting liver metastasis from rectal cancer (RC).

METHODS

The clinical data of 599 locally advanced RC patients treated with chemoradiotherapy followed by surgery were reviewed. Serum apoAI, apoB and apoB-to-apoAI ratio were analyzed for their correlation with the liver-metastasis-free, other-metastasis-free and overall survivals, together with the pretreatment and postsurgical pathoclinical features of the patients. Univariate and multivariate survival analyses were realized through the Kaplan-Meier approach and Cox model, respectively. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for independent predictors.

RESULTS

Carbohydrate antigen 19 - 9 ≥ 26.3 U/ml, apoB-to-apoAI ratio ≥ 0.63, tumor regression grade 5 - 3, pT4 and pN + stage emerged as independent predictors of poorer liver-metastasis-free survival. The hazard ratios were 1.656 (95% CI, 1.094-2.506), 1.919 (95% CI, 1.174-3.145), 1.686 (95% CI, 1.053-2.703), 1.890 (95% CI, 1.110-3.226) and 2.012 (95% CI, 1.314-2.077), respectively. Except apoB-to-apoAI ratio, the other 4 factors were also independent predictors of poorer other-metastasis-free and overall survivals. And the independent predictors of poorer overall survival also included age ≥ 67 years old, distance to anal verge < 5 cm.

CONCLUSIONS

Serum apoB-to-apoAI ratio could be used as a biomarker for prediction of liver metastasis risk in locally advanced RC.

Mutational status of plasma exosomal KRAS predicts outcome in patients with metastatic colorectal cancer

Liquid biopsy has become a useful alternative in metastatic colorectal cancer (mCRC) patients when tissue biopsy of metastatic sites is not feasible. In this study we aimed to investigate the clinical utility of circulating exosomes DNA in the management of mCRC patients. Exosomes level and KRAS mutational status in exosomal DNA was assesed in 70 mCRC patients and 29 CRC primary tumor and were analysed at different disease steps evaluating serial blood samples (240 blood samples). There was a significant correlation between the extension of disease and exosomes level and the resection of primary localized tumor was correlated with a decrease of KRAS G12V/ D copies and fractional abundance in metastatic disease. CEA expression and liver metastasis correlated with a higher number of KRAS G12V/D copies/ml and a higher fractional abundance; in the subgroup of mCRC patients eligible for surgery, the size of tumor and the radiological response were related to exosomes level but only the size was related to the number of KRAS WT copies; both KRAS wild-type and mutated levels were identified as a prognostic factor related to OS. Finally, we found that 91% of mutated mCRC patients became wild type after the first line chemotherapy but this status reverted in mutated one at progression in 80% of cases. In a prospective cohort of mCRC patients, we show how longitudinal monitoring using exosome-based liquid biopsy provides clinical information relevant to therapeutic stratification.

Peripheral blood CD45RO+T cells is a predictor of the effectiveness of neoadjuvant chemoradiotherapy in locally advanced rectal cancer

To investigate the relationship between the changes in circulating CD45RO+T lymphocyte subsets following neoadjuvant therapy for rectal cancer in patients with locally advanced rectal cancer.The clinicopathological data of 185 patients with rectal cancer who received neoadjuvant therapy in the General Surgery Department of Beijing Chaoyang Hospital affiliated to Capital Medical University from June 2015 to June 2017 were analyzed. Venous blood samples were collected 1 week before neoadjuvant therapy and 1 week before surgery, and the expression of CD45RO+T was detected by flow cytometry. The receiver operating characteristic curve analysis was used to determine the optimal cut-off point of CD45RO+ratio. Log-rank test and multivariate Cox regression were used to analyze the overall survival rate (OS) and disease-free survival rate (DFS) associated with CD45RO+ratio.Circulating CD45RO+ratio of 1.07 was determined as the optimal cut-off point and CD45RO+ratio-high was associated with lower tumor regression grade grading (P = .031), T stage (P = .001), and tumor node metastasis (TNM) stage (P = .012). The 3-year DFS and OS rate in the CD45RO+ratio-high group was significantly higher than that in the CD45RO+ratio-low group (89.2% vs 60.1%, P<.001; 94.4% vs 73.2%, P<.001). The multivariate Cox analysis revealed that elevated CD45RO+ratio was an independent factor for better DFS (OR, 0.339; 95% CI, 0.153-0.752; P = .008) and OS (OR, 0.244; 95% CI,0.082-0.726; P = .011).Circulating CD45RO+ratio could predict the tumor regression grade of neoadjuvant therapy for rectal cancer, as well as long-term prognosis. These findings could be used to stratify patients and develop alternative strategies for adjuvant therapy.

Associations between hepatitis B virus exposure and the risk of extrahepatic digestive system cancers: A hospital-based, case-control study (SIGES)

OBJECTIVES

This case-control study was aimed to investigate associations between HBV infection and extrahepatic digestive system cancers.

METHODS

The patients of gastric, small intestinal, colonic, rectal, anal, biliary tract, and pancreatic cancers were retrospectively collected between 2016.5 and 2017.12. Simultaneously, the healthy controls were collected from the health check-up registry, and cancer-free status was confirmed based on medical records. Propensity score matching was performed to reduce bias. Multinomial logit model and conditional logistic regression model were used to assess the risk of individual cancer according to HBV serological markers and classifications.

RESULTS

Totally, 4748 patients involving seven cancers, and 57,499 controls were included. After matching, HBsAg was associated with increased risk of gastric cancer (aOR = 1.39, 95% CI: 1.05-1.85), and anti-HBs served as a protective factor for gastric (aOR = 0.72, 95% CI: 0.61-0.85), colonic (aOR = 0.73, 95% CI: 0.60-0.89), rectal (aOR = 0.73, 95% CI: 0.63-0.85), and pancreatic (aOR = 0.58, 95% CI: 0.42-0.82) cancers. Compared to subgroups with non-infection and vaccination status, inactive HBsAg carriers and active HBV infection subgroup were correlated with gastric carcinogenesis (aOR = 1.41, 95% CI: 1.03-1.93). However, no clear association was found between HBV infection and other cancers.

CONCLUSIONS

HBV infection was potentially associated with an increased risk of gastric cancer. The development mechanism of HBV-associated gastric cancer needs to investigate further.

Combination of Preoperative Plasma Fibrinogen and Neutrophil-to-Lymphocyte Ratio (the F-NLR Score) as a Prognostic Marker of Locally Advanced Rectal Cancer Following Preoperative Chemoradiotherapy

BACKGROUND

Coagulation and inflammation play important roles in tumor progression. This study aimed to explore the prognostic impact of combined analysis of fibrinogen and neutrophil-to-lymphocyte (NLR) ratio (F-NLR score) in locally advanced rectal cancer (LARC) receiving preoperative chemoradiotherapy (pCRT) and radical surgery.

METHOD

Totally 317 patients were included. X-tile analysis was used to determine the optimal cutoff values of preoperative fibrinogen and NLR. F-NLR scores were defined as 2 (both high fibrinogen and NLR), 1 (one of these abnormalities), or 0 (neither abnormality). Time-dependent ROC analysis was used to evaluate the predictive accuracy of fibrinogen, NLR, and F-NLR score. Cox regression analysis was performed to evaluate the prognostic impact of the F-NLR score. A predictive nomogram for disease-free survival (DFS) was developed and validated internally.

RESULTS

One hundred and seventeen (36.9%), 156 (49.2%), and 44 (13.9%) patients had F-NLR score of 0, 1, and 2, respectively. Higher F-NLR score was associated with poorly differentiated tumors, deeper tumor invasion, lymph node metastasis, and more advanced pTNM stage (all P < 0.05). The 5-year OS rates in the F-NLR 0, 1, and 2 groups were 93.6%, 87.3%, and 68.4%, respectively (P < 0.001), while the 5-year DFS rates were 91.8%, 76.8%, and 56.1%, respectively (P < 0.001). Cox regression analysis demonstrated that F-NLR score (F-NLR 1, HR = 2.021, P = 0.046; F-NLR 2, HR = 3.356, P = 0.002), pTNM stage III (HR = 3.109, P = 0.009), and circumferential resection margin (CRM) involvement (HR = 3.120, P = 0.021) were independently associated with DFS. A nomogram for DFS was developed (C-index 0.708).

CONCLUSION

F-NLR score is a promising predictor for disease recurrence in LARC patients after pCRT.

ctDNA applications and integration in colorectal cancer: an NCI Colon and Rectal-Anal Task Forces whitepaper

An increasing number of studies are describing potential uses of circulating tumour DNA (ctDNA) in the care of patients with colorectal cancer. Owing to this rapidly developing area of research, the Colon and Rectal-Anal Task Forces of the United States National Cancer Institute convened a panel of multidisciplinary experts to summarize current data on the utility of ctDNA in the management of colorectal cancer and to provide guidance in promoting the efficient development and integration of this technology into clinical care. The panel focused on four key areas in which ctDNA has the potential to change clinical practice, including the detection of minimal residual disease, the management of patients with rectal cancer, monitoring responses to therapy, and tracking clonal dynamics in response to targeted therapies and other systemic treatments. The panel also provides general guidelines with relevance for ctDNA-related research efforts, irrespective of indication.

Adnexal masses in patients with colorectal cancer

OBJECTIVE

To evaluate the clinicopathological features and outcomes of patients undergone surgery for benign and metastatic adnexal masses during the surveillance of colorectal cancer (CRC).

METHODS

A single institute retrospective study involving 90 patients diagnosed with CRC that undergone surgery at Hacettepe University Hospital between 2000-2018. Clinicopathological and survival data was obtained from hospital records.

RESULTS

Elevated blood levels of CEA (HR, 1.23; 95 % CI: 1.03-1.24; p = 0.01), adnexal masses larger than 5 cm (HR, 3.296; 95 % CI: 1.527-7.076; p = 0.002), bilaterality of adnexal mass (HR, 2.200; 95 % CI: 2.464-11.969; p = 0.001) and high PCI score (HR, 0.150; 95 % CI: 0.044-0.479; p = 0.01) were found to be significantly associated with ovarian metastasis. There was a significant difference in overall survival (OS), with respect to complete and incomplete resection in adnexal surgery of ovarian metastasis (46.6 vs. 29.6 months; p = 0.004). The median survival time was 32.8 months for patients with ≤ 24 months interval time to adnexal metastasis surgery, and 48.5 months for patients with >24 months interval time to adnexal metastasis surgery (p = 0.001).

CONCLUSION

This study showed that numerous clinicopathological variables such as bilaterality and size of adnexal mass, serum blood levels of CEA and PCI score may have a significant impact on the prediction and management of ovarian masses diagnosed during CRC surveillance. Complete resection and interval time to adnexal surgery is significantly associated with OS.

Expression levels of circulating miRNAs as biomarkers during multimodal treatment of rectal cancer - TiMiSNAR-mirna: a substudy of the TiMiSNAR Trial (NCT03962088)

BACKGROUND

Neoadjuvant chemoradiotherapy followed by surgery is the mainstay treatment for locally advanced rectal cancer, leading to significant decrease in tumor size (downsizing) and a shift towards earlier disease stage (downstaging). Extensive histopathological work-up of the tumor specimen after surgery including tumor regression grading and lymph node status helped to visualize individual tumor sensitivity to chemoradiotherapy, retrospectively. As the response to neoadjuvant chemoradiotherapy is heterogeneous, however, valid biomarkers are needed to monitor tumor response. A relevant number of studies aimed to identify molecular markers retrieved from tumor tissue while the relevance of blood-based biomarkers is less stringent assessed. MicroRNAs are currently under investigation to serve as blood-based biomarkers. To date, no screening approach to identify relevant miRNAs as biomarkers in blood of patients with rectal cancer was undertaken. The aim of the study is to investigate the role of circulating miRNAs as biomarkers in those patients included in the TiMiSNAR Trial (NCT03465982). This is a biomolecular substudy of TiMiSNAR Trial (NCT03962088).

METHODS

All included patients in the TiMiSNAR Trial are supposed to undergo blood collection at the time of diagnosis, after neoadjuvant treatment, after 1 month from surgery, and after adjuvant chemotherapy whenever indicated.

DISCUSSION

TiMiSNAR-MIRNA will evaluate the association of variation between preneoadjuvant and postneoadjuvant expression levels of miRNA with pathological complete response. Moreover, the study will evaluate the role of liquid biopsies in the monitoring of treatment, correlate changes in expression levels of miRNA following complete surgical resection with disease-free survival, and evaluate the relation between changes in miRNA during surveillance and tumor relapse.

TRIAL REGISTRATION

Clinicaltrials.gov NCT03962088 . Registered on 23 May 2019.

Prognostic value of pretreatment tumor-to-blood standardized uptake ratio (SUR) in rectal cancer

OBJECTIVES

The prognostic value of SUV on pretreatment F-18 FDG PET/CT imaging in patients with rectal cancer is a matter of debate. SUR is of prognostic value for survival in different cancers. In this study, we aimed to examine the potential prognostic value of SUR and other parameters in pretreatment F-18 FDG PET/CT for non-metastatic rectal cancer.

METHODS

One hundred four non-metastatic rectal cancer patients who underwent pretreatment PET/CT between March 2012 and January 2018 were included in the study. Firstly, SUV_max, SUV_mean, MTV, and TLG were calculated semi-automatically at the workstation. SUR was calculated as the ratio of tumor SUV_max to thoracic aorta blood SUV_mean. Univariate Cox regression and Kaplan-Meier analysis were used to evaluate overall survival (OS), progression free survival (PFS), and local recurrence (LR). Then, multivariate Cox regression analysis, which included the parameters that were significant in the univariate analysis, was performed.

RESULTS

Multivariate Cox regression analysis revealed that SUR was a prognostic factor for PFS. Age and T stage were prognostic factors for both OS and PFS. MTV was found to be independent risk factors for OS.

CONCLUSIONS

In our study, SUR was the only F-18 FDG PET/CT parameter found to be significant for PFS. The development of new parameters can increase the prognostic value of F-18 FDG PET/CT.

High platelet-to-lymphocyte ratio predicts improved survival outcome for perioperative NSAID use in patients with rectal cancer

PURPOSE

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to block tumor-associated inflammation in rectal cancer. However, the perioperative use of NSAIDs remains controversial. This study was designed to investigate whether the perioperative use of NSAIDs influences outcomes and to provide a predictive marker to identify patients who would benefit from NSAIDs.

METHODS

We enrolled 515 patients with stage I to III rectal cancer in this retrospective study. Patients were classified into the NSAID and non-NSAID groups according to their perioperative use of NSAIDs. The whole cohort was stratified by platelet-to-lymphocyte ratio (PLR). The primary endpoints were disease-free survival (DFS) and overall survival (OS).

RESULTS

The NSAID group had a 12.6% lower risk of recurrence than the non-NSAID group (P = 0.015), while the association with survival was nonsignificant. In the high-PLR subset, the NSAID group had a 17.3% lower risk of recurrence (P = 0.003) and a better DFS (P = 0.033) outcome than the non-NSAID group. Multivariate analysis confirmed this independent significant association with DFS (P = 0.023). In the low-PLR subset, the association of NSAID use with survival was nonsignificant.

CONCLUSION

Perioperative use of NSAIDs was associated with improved survival outcomes in rectal cancer patients with high PLR.

High neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio predict poor survival in rectal cancer patients receiving neoadjuvant concurrent chemoradiotherapy

This study explored the prognostic value of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in rectal cancer patients receiving neoadjuvant concurrent chemoradiotherapy (CCRT).Between January 2006 and December 2016, 184 patients with newly-diagnosed rectal cancer receiving neoadjuvant CCRT were enrolled. Risk of overall survival (OS) and disease-free survival (DFS) were calculated using the Kaplan-Meier method and Cox proportional hazard models. Stratified survival analyses were also performed between post-neoadjuvant pathological (yp) stage.The mean follow-up time was 72.73 ± 36.82 months. High- and low-NLR patients differed significantly in both 5-year DFS (P = .026) and OS (P = .016). High- and low-PLR patients differed significantly in 5-year DFS (P = .011) but not OS (P = .185). Multivariate analyses revealed worse 5-year DFS (adjusted HR [aHR] = 2.8; 95% CI: 1.473-5.41; P = .002) and 5-year OS (aHR = 1.871; 95%CI: 1.029-3.4; P = .04) in the high-NLR group after adjusting for covariates. After adjustments, the high-PLR group had inferior 5-year DFS (aHR = 2.274; 95%CI: 1.473-5.419; P = .038) but not 5-year OS (aHR = 1.156; 95%CI: 0.650-2.056; P = .622). Further stratified analysis indicated that yp stage II and III patients with high NLR had worse 5-year DFS (aHR = 2.334; 95% CI: 1.158-4.725; P = .018) and OS (aHR = 2.226; 95% CI: 1.165-4.251; P = .015). Additionally, yp stage II and III patients with high PLR had inferior 5-year DFS (aHR = 2.012; 95% CI: 1.049-3.861; P = .036).Pre-CCRT NLR and PLR are independent prognostic factors for rectal cancer patients and could be used as a potential biomarker to identify high-risk patients for more intense treatment and care.

MRI Tumor Regression Grade and Circulating Tumor DNA as Complementary Tools to Assess Response and Guide Therapy Adaptation in Rectal Cancer

PURPOSE

Response to preoperative chemo-radiotherapy (CRT) varies. We assessed whether circulating tumor DNA (ctDNA) might be an early indicator of tumor response or progression to guide therapy adaptation in rectal cancer.

EXPERIMENTAL DESIGN

A total of 243 serial plasma samples were analyzed from 47 patients with localized rectal cancer undergoing CRT. Up to three somatic variants were tracked in plasma using droplet digital PCR. RECIST and MRI tumor regression grade (mrTRG) evaluated response. Survival analyses applied Kaplan-Meier method and Cox regression.

RESULTS

ctDNA detection rates were: 74% (n = 35/47) pretreatment, 21% (n = 10/47) mid CRT, 21% (n = 10/47) after completing CRT, and 13% (n = 3/23) after surgery. ctDNA status after CRT was associated with primary tumor response by mrTRG (P = 0.03). With a median follow-up of 26.4 months, metastases-free survival was shorter in patients with detectable ctDNA after completing CRT [HR 7.1; 95% confidence interval (CI), 2.4-21.5; P < 0.001], persistently detectable ctDNA pre and mid CRT (HR 3.8; 95% CI, 1.2-11.7; P = 0.02), and pre, mid, and after CRT (HR 11.5; 95% CI, 3.3-40.4; P < 0.001) compared with patients with undetectable or nonpersistent ctDNA. In patients with detectable ctDNA, a fractional abundance threshold of ≥0.07% mid CRT or ≥0.13% after completing CRT predicted for metastases with 100% sensitivity and 83.3% specificity for mid CRT and 66.7% for CRT completion. All 3 patients with detectable ctDNA post-surgery relapsed compared with none of the 20 patients with undetectable ctDNA (P = 0.001).

CONCLUSIONS

ctDNA identified patients at risk of developing metastases during the neoadjuvant period and post-surgery, and could be used to tailor treatment.

Device for whole genome sequencing single circulating tumor cells from whole blood

Whole-genome sequencing on circulating tumor cells (CTCs) at the single cell level has recently been found helpful for precision medicine, as the oncogenic profiles of single CTCs are useful for discovering oncogenic mutation heterogeneities and guiding/adjusting cancer treatment. To overcome the limits of existing methods of single CTC sequencing, in which CTC enrichment, identification and gene amplification are performed by discrete modules, this study presents a novel method in which all processing steps from blood sample collection to preparation of gene amplification products for sequencers are finished in a single microfluidic chip. This microfluidic chip comprehensively performs blood filtering, CTC enrichment, CTC identification/isolation, CTC lysis and whole genome amplification (WGA) at the single cell level. By sequencing single CTCs from clinical blood samples with pointing key driver and drug-resistance mutations, the novel microfluidic chip was validated to be capable of genetically profiling single CTCs with minimum cell loss/human labor, and more importantly, high accuracy and repeatability, which are crucial factors for promoting clinical application of single CTC sequencing.

Prognostic value of preoperative carcinoembryonic antigen/tumor size in rectal cancer

BACKGROUND

Carcinoembryonic antigen (CEA) is a commonly used biomarker in colorectal cancer. However, controversy exists regarding the insufficient prognostic value of preoperative serum CEA alone in rectal cancer. Here, we combined preoperative serum CEA and the maximum tumor diameter to correct the CEA level, which may better reflect the malignancy of rectal cancer.

AIM

To assess the prognostic impact of preoperative CEA/tumor size in rectal cancer.

METHODS

We retrospectively reviewed 696 stage I to III rectal cancer patients who underwent curative tumor resection from 2007 to 2012. These patients were randomly divided into two cohorts for cross-validation: training cohort and validation cohort. The training cohort was used to generate an optimal cutoff point and the validation cohort was used to further validate the model. Maximally selected rank statistics were used to identify the optimum cutoff for CEA/tumor size. The Kaplan-Meier method and log-rank test were used to plot the survival curve and to compare the survival data. Univariate and multivariate Cox regression analyses were used to determine the prognostic value of CEA/tumor size. The primary and secondary outcomes were overall survival (OS) and disease-free survival (DFS), respectively.

RESULTS

In all, 556 patients who satisfied both the inclusion and exclusion criteria were included and randomly divided into the training cohort (2/3 of 556, n = 371) and the validation cohort (1/3 of 556, n = 185). The cutoff was 2.429 ng/mL per cm. Comparison of the baseline data showed that high CEA/tumor size was correlated with older age, high TNM stage, the presence of perineural invasion, high CEA, and high carbohydrate antigen 19-9 (CA 19-9). Kaplan-Meier curves showed a manifest reduction in 5-year OS (training cohort: 56.7% vs 81.1%, P < 0.001; validation cohort: 58.8% vs 85.6%, P < 0.001) and DFS (training cohort: 52.5% vs 71.9%, P = 0.02; validation cohort: 50.3% vs 79.3%, P = 0.002) in the high CEA/tumor size group compared with the low CEA/tumor size group. Univariate and multivariate analyses identified CEA/tumor size as an independent prognostic factor for OS (training cohort: hazard ratio (HR) = 2.18, 95% confidence interval (CI): 1.28-3.73, P = 0.004; validation cohort: HR = 4.83, 95%CI: 2.21-10.52, P < 0.001) as well as DFS (training cohort: HR = 1.47, 95%CI: 0.93-2.33, P = 0.096; validation cohort: HR = 2.61, 95%CI: 1.38-4.95, P = 0.003).

CONCLUSION

Preoperative CEA/tumor size is an independent prognostic factor for patients with stage I-III rectal cancer. Higher CEA/tumor size is associated with worse OS and DFS.

Leptin and adiponectin dynamics at patients with rectal neoplasm - Gender differences

Background

Numerous studies associate adipokines with colorectal malignancy, but few data deal with patients suffering exclusively of rectal carcinoma (RC).

Aims

We evaluated leptin and adiponectin levels in RC patients compared to healthy population and their dynamics after surgery.

Material and methods

Serum leptin and adiponectin were evaluated before surgery in 59 RC consecutive patients (38 males and 21 females), and in age and weight matched healthy controls. Measurements were repeated at 24, 72 hours and 7 days after surgery.

Results

Adipokine levels were higher in women. Controls had higher leptin (32.±4.34 vs 9.51±1.73 ng/ml in women and 11±2.66 vs 2.54±0.39 ng/ml in men, p = 0.00048 and 0.0032) and lower adiponectin (9±0.64 vs 11.85±1.02 μg/ml in women and 7.39±0.51 vs 8.5±0.62 μg/ml in men, p = 0.017 and 0.019) than RC patients. Surgery caused an increase of leptin from 5.11±0.8 to 18.7±2.42 ng/ml, p = 6.85 x 10¨⁸, and a decrease of adiponectin from 9.71±0.58 to 7.87±0.47 μg/ml, p = 1.4 x 10¨¹⁰ for all RC patients and returned thereafter to the initial range at 7 days. Adipokines were correlated with body weight (BW). The significance of correlation persisted after surgery only in males, but disappeared in females. Adipokines were not modified by tumor position, presurgical chemoradiotherapy or surgical technique. Women with RC experiencing weight loss had higher adiponectin than women without weight modifications (p<0.05 at all time points).

Conclusions

Adipokine levels of patients with RC differ from the healthy population, possibly reflecting an adaptation to disease. Adipokine modifications after surgery may be related to acute surgical stress. Whether leptin and adiponectin directly interact is not clear. Women have higher adipokine levels, more so after significant weight loss, but the strength of their correlation with BW decreases after surgery. These data suggest gender differences in the adipokine profile of RC patients which may find clinical applications.

Prognostic value of preoperative albumin to globulin ratio in elderly patients with rectal cancer

To identify the value of predictors of poor prognosis of elderly patients with rectal cancer who underwent surgery, we investigated the relations between albumin to globulin ratio (AGR) and clinicopathological findings.We conducted a retrospective cohort study of clinicopathological characteristics (general status, pathological features of tumors, preoperative laboratory data, disease free, and overall survival) for elderly patients with stage I-III rectal cancer. The AGR is calculated as albumin/(total protein - albumin).According to the optimal cut-off point of AGR (1.43), the enrolled patients were divided into low AGR (n = 83) and high AGR (n = 136) groups. Meanwhile, age, hemoglobin, tumor size, and differentiation degree were the independent risk factors of low preoperative AGR value. Compared to patients with high AGR, those with low AGR were related to worse disease-free survival (DFS) (P = .0008) and overall survival (OS) (P = .0003). Moreover, in multivariate analysis, low AGR and poor TNM stage were the independent predictor of poor DFS and OS. Finally, the nomograms illustrated the effect of prognostic factors on DFS and OS.Preoperative AGR has a significant prognostic value and was identified as an independent predictor of DFS and OS in elderly rectal cancer patients.

Neutrophil-to-Lymphocyte Ratio in Rectal Cancer-Novel Biomarker of Tumor Immunogenicity During Radiotherapy or Confounding Variable?

The aim of this study was to investigate the predictive value of blood-derived makers of local and systemic inflammatory responses on early and long-term oncological outcomes. A retrospective analysis of patients with locally advanced rectal cancer treated with preoperative long-course 5-fluorouracil-based radiochemotherapy was performed. Differential blood counts before neoadjuvant treatment were extracted from the patients' electronic charts. Optimal cut-off values for neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) were determined. Potential clinical and hematological prognostic factors for disease-free survival (DFS) were studied using uni- and multivariate analysis. A total of 220 patients were included in the analysis. Median follow-up was 67 months. Five-year DFS and overall survival (OS) were 70% and 85%, respectively. NLR with a cut-off value of 4.06 was identified as optimal to predict DFS events. In multivariate analysis, only tumor volume (HR 0.33, 95% CI (0.14-0.83), p = 0.017) and NLR (HR 0.3, 95% CI (0.11-0.81), p = 0.017) remained significant predictors of DFS. Patients with a good histological response (Dworak 3 and 4) to radiotherapy also had a lower NLR than patients with less pronounced tumor regression (3.0 vs. 4.2, p = 0.015). A strong correlation between primary tumor volume and NLR was seen (Pearson's r = 0.64, p < 0.001). Moreover, patients with T4 tumors had a significantly higher NLR than patients with T1-T3 tumors (6.6 vs. 3.3, p < 0.001). An elevated pretherapeutic NLR was associated with higher T stage, inferior DFS, and poor pathological response to neoadjuvant radiochemotherapy. A strong correlation between NLR and primary tumor volume was seen. This association is important for the interpretation of study results and for the design of translational studies which are warranted.

Utilization of Next Generation Sequencing in Analysis of Circulating MicroRNAs as Predictive Biomarkers for Patients with Locally Advanced Rectal Carcinoma

BACKGROUND

MicroRNAs (miRNA) are short non-coding RNAs involved in post-transcriptional regulation of gene expression. MiRNAs are essential regulators of both physiological processes as of pathogeneses of many diseases, and their dysregulation was observed in many malignancies including rectal cancer. Circulating miRNAs presented in blood plasma could be potential candidates for non-invasive predictive biomarkers of the response of patients with locally advanced rectal cancer to chemoradiotherapy. Presented study aims to evaluate the potential of next-generation sequencing in the analysis of circulating miRNAs.

MATERIAL AND METHODS

MiRNA expression profiles were done using samples of RNA isolated from blood plasma collected during TNM restaging and paired samples collected before initiation of neoadjuvant chemoradiotherapy. Sequencing libraries were prepared using kit which implements universal molecular indices that help to sensitively filter biological bias during data analysis. Sequencing data were processed by multidimensional biostatistical approaches.

CONCLUSION

We identified specific miRNA profile enabling to distinguish the patients accordingly to their response to chemoradiotherapy. This work was supported by the Czech Ministry of Health grant No. 16-31765A. The authors declare they have no potential confl icts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 22. 2. 2019 Accepted: 27. 2. 2019.