Follow-up Of Colorectal Cancer Patients Research Articles

Understanding colorectal cancer patient follow-up: a qualitative interview study.

There are increasing numbers of patients who have been treated for colorectal cancer (CRC) who struggle with ongoing physical and psychological symptoms. 'Cancer survivor' is often used to describe these patients but this terminology remains controversial. This study sought to understand the follow-up experience of CRC patients in the UK and identify the terminology they prefer following diagnosis and treatment. Purposeful sampling of patients from specialist CRC follow-up clinics was performed until data saturation was achieved. Two 1:1 semi-structured qualitative interviews were performed for each participant. Data were analysed thematically. Seventeen participants, median age = 62, 53% male were interviewed. Several themes were identified. Of note, fear of cancer recurrence dominates patients' agendas at follow-up appointments. There are also clinical and administrative barriers to discussing symptoms including being embarrassed, feeling that their symptoms were not relevant or not having enough time to discuss issues. However, there are several methods which may improve this, such as through the use of video consultations and questionnaires. In addition, patients identified inadequate holistic support despite significant psychological and social distress. Our data suggest that labelling a diverse group of patients as 'cancer survivors' can be problematic. It is important that clinicians systematically screen patients for symptoms that are known to occur following treatment. Clinicians and patients should have routine access to pathways and programmes that can support patients in navigating their life after cancer therapy.

MiR-1 Variations in Colorectal Cancer: Possible Implementation as a Potential Accessory Biomarker

Background and Aims: Colorectal cancer (CRC) is one of the most common human cancers. Currently, carcinoembryonic antigen (CEA) is used as the main standard biomarker of CRC, though this biomarker is not specifically made for CRC and, in a minority of cases, shows inadequate sensitivity. Therefore, searching for novel accessory biomarkers may fill these gaps in clinical management. miRNAs physiologically regulate various metabolic processes and are misregulated in various cancers. Therefore, the present investigation was conducted to evaluate miR-1 levels in CRC samples.
 Materials and Methods: The CRC and adjacent tissue samples were obtained from 24 patients. In addition, sera were collected from the patient group and 24 healthy controls. Total RNA was extracted from tissue samples, and cDNA was synthesized. Real-time PCR determined the expression of miR-1. Serum levels of CEA were also measured using a Monobind ELISA assay kit.
 Results: The level of miR-1 in CRC tumors was significantly down-regulated. Moreover, patients with metastasis showed lower expression of miR-1 compared to cases without metastasis; however, this difference was not statistically significant. The ROC curve for miR-1 showed an AUC of 0.69. In addition, ROC analysis revealed a sensitivity of 70.27% and a specificity of 62.96% for miR-1.
 Conclusion: There is still a need for new upcoming markers in addition to the main CRC biomarker, CEA. The levels of miR-1 in colorectal cancer tissue samples may provide additional information for the management and follow-up of CRC patients; though, the clinical application needs further studies.

The histopathological features and their prognostic impact in the postoperative follow-up of colorectal cancer patients.

The validation of histological prognostic markers in colorectal cancer not only for survival parameters but also for early postoperative outcomes is of paramount importance. The aim of our study was to search for the tumor histopathological (HP) characteristics that may influence the postoperative morbidity, especially the occurrence of anastomotic leakage. Our results indicated that peritumoral inflammatory cell infiltrate appeared to correlate with both anastomotic fistula and overall postoperative complications. Likewise, high-grade and undifferentiated colorectal tumors seemed to be correlated with a higher incidence of postoperative leakage and complications. No relation could be established between the other HP features and the postoperative untoward outcomes.

Quality Indicators and Outcomes in a Prospective Cohort of Colorectal Cancer Patients.

Some quality indicators of proper health care in patients with colorectal cancer have been established. Our goal was to evaluate the relationship between performing of certain procedures or treatments, included as quality indicators, and some outcomes of indicators in the follow-up of colorectal cancer patients. This was a prospective cohort study of patients diagnosed with colorectal cancer that underwent surgery and were followed at 1, 2, 3, and 5years. CT scanning, colonoscopy, chemotherapy, and radiotherapy were evaluated in relation to various clinical outcomes and PROM changes over 5years. Multivariable generalized linear mixed models were used to evaluate their effect on mortality, complications, recurrence, and PROM changes (HAD, EQ-5D, EORTC-Q30) at the next follow-up. CT scanning or colonoscopy was related to a decrease in the risk of dying, while chemotherapy at a specified moment was related to an increased risk. In the case of recurrence, CT scanning and chemotherapy showed statistically increased the risk, while all the procedures and treatments influenced complications. Regarding PROM scales, CT scanning, colonoscopy, and radiotherapy showed statistically significant results with respect to an increase in anxiety and decrease in quality of life measured by the EORTC. However, undergoing radiotherapy at a specified moment increased depression levels, and overall, receiving radiotherapy decreased the quality of life of the patients, as measured by the EuroQol-5d. After adjustment for sociodemographic factors, comorbidities, and severity of the disease, performing certain quality indicators of proper health care in patients with colorectal cancer was related to less mortality but higher adverse outcomes. ClinicalTrials.gov Identifier: NCT02488161.

1695P ePRO follow-up of colorectal cancer patients receiving oxaliplatin-based adjuvant chemotherapy is feasible and enhances the quality of patient care

Electronic patient reported outcomes (ePROs) have been shown to improve the quality of life and survival, and reduce the number of unscheduled health care visits in chemotherapy treated patients (pts) with advanced cancers. We hypothesized that ePRO follow-up could improve symptom management, streamline patient flow, and reduce the use of additional healthcare resources among colorectal cancer (CRC) pts treated with oxaliplatin-based chemotherapy in adjuvant setting.

The value of NLR, FIB, CEA and CA19-9 in colorectal cancer

Objective: To investigate the clinical value of neutrophil-lymphocyte ratio (NLR), fibrinogen (FIB), carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) in the diagnosis and prognosis of colorectal cancer. Methods: A case-control study design was used to select 155 patients with colorectal cancer[98 males and 57 females, aged (63.12±13.99)years old], 90 patients with colorectal polyps[62 males and 28 females, aged (56.86±12.74)years old] and 150 healthy subjects[93 males and 57 females, aged (57.02±10.91)years old] from the First Affiliated Hospital of Nanjing Medical University from October 2017 to March 2018. Blood routine tests were detected by instrument method, FIB was detected by Clauss method, and CEA and CA19-9 were detected by electrochemiluminescence method. The levels of the NLR, FIB, CEA and CA19-9 in the 3 groups were compared. The diagnostic efficacy of NLR, FIB, CEA and CA19-9 of colorectal cancer was compared according to the ROC curve. The relationship between the level of NLR, FIB, CEA and CA19-9 and their clinicopathological features in colorectal cancer patients was assessed. According to the median levels of NLR, FIB, CEA and CA19-9, 112 follow-up of colorectal cancer patients could be divided into the high-value group and the low-value group. Kaplan-Meier, log-rank test and Cox regression analysis were used to analyze the relationship between the levels of the four indicators and the prognosis of colorectal cancer. Results: The levels of NLR, FIB, CEA and CA19-9 in colorectal cancer group were 2.11(1.52, 2.86), 3.21(2.58, 3.86)g/L, 3.93(2.27, 8.78)μg/L, 15.11(9.10, 25.73)U/ml. The levels of NLR, FIB, CEA and CA19-9 in colorectal polyp group were 1.74(1.39, 2.17), 2.54(2.26, 3.03)g/L, 1.99(1.18, 2.70)μg/L, 9.83(6.13, 15.68)U/ml. The levels of NLR, FIB, CEA and CA19-9 in healthy control group were 1.68(1.33, 2.28), 2.56(2.30, 2.82)g/L, 1.85(1.28, 2.59)μg/L, 10.03(6.86, 13.26)U/ml. The levels of NLR, FIB, CEA and CA19-9 in colorectal cancer group were significantly higher than those in colorectal polyp group (Z values were 3.568, 5.913, 6.880 and 4.022,P values were all<0.05) and healthy control group(Z values were 3.916, 7.381, 9.131 and 5.251,P values were all<0.05). The levels of NLR, FIB, CEA and CA19-9 in colorectal polyp group were not remarkably different from those in healthy control group (Z values were 0.217, 0.179, 0.320 and 0.061,P values were all>0.05). The diagnostic performance of CEA was the best in single test, followed by FIB, CA19-9 and NLR. The sensitivity of combined NLR+FIB+CEA or NLR+FIB+CEA+CA19-9 was the highest with 72.3%. NLR and FIB levels were associated with tumor sites (Z values were 3.587 and 7.089,P values were both<0.05). FIB and CEA levels were correlated with the depth of tumor invasion (Z values were 3.250 and 3.245, P values were both <0.05). NLR, FIB, CEA and CA19-9 levels were both associated with lymph node metastasis (Z values were 2.010, 3.276, 3.312 and 2.921, P values were all<0.05). The prognosis of patients in the high-value NLR, FIB, CEA and CA19-9 groups was significantly worse than that in the low-value group (χ2 values were 5.744, 6.048, 4.389 and 6.942,P values were all<0.05).Cox multivariate regression analysis showed lymph node metastasis, NLR >2.15 and CA19-9 >15.47 U/ml are independent factors affecting the prognosis of colorectal cancer. Conclusion: NLR, FIB, CEA and CA19-9 can be applied in the auxiliary diagnosis and prognosis of colorectal cancer.

A prognostic model for colorectal cancer based on CEA and a 48-multiplex serum biomarker panel

Mortality in colorectal cancer (CRC) remains high, resulting in 860,000 deaths annually. Carcinoembryonic antigen is widely used in clinics for CRC patient follow-up, despite carrying a limited prognostic value. Thus, an obvious need exists for multivariate prognostic models. We analyzed 48 biomarkers using a multiplex immunoassay panel in preoperative serum samples from 328 CRC patients who underwent surgery at Helsinki University Hospital between 1998 and 2003. We performed a multivariate prognostic forward-stepping background model based on basic clinicopathological data, and a multivariate machine-learned prognostic model based on clinicopathological data and biomarker variables, calculating the disease-free survival using the value of importance score. From the 48 analyzed biomarkers, only IL-8 emerged as a significant prognostic factor for CRC patients in univariate analysis (HR 4.88; 95% CI 2.00–11.92; p = 0.024) after correcting for multiple comparisons. We also developed a multivariate model based on all 48 biomarkers using a random survival forest analysis. Variable selection based on a minimal depth and the value of importance yielded two tentative candidate CRC prognostic markers: IL-2Ra and IL-8. A multivariate prognostic model using machine-learning technologies improves the prognostic assessment of survival among surgically treated CRC patients.

Building Consensus for the Follow-up of Colorectal Cancer Patients by Primary Care: A Nominal Group Technique Study

Building Consensus for the Follow-up of Colorectal Cancer Patients by Primary Care: A Nominal Group Technique Study

Characterisation of long-term cancer survivors and application of statistical cure models: a protocol for an observational follow-up study in patients with colorectal cancer

BackgroundImproved colorectal cancer (CRC) survival rates have been reported over the last years, with more than half of these patients surviving more than 5 years after the initial diagnosis. Better understanding these so-called long-term survivors could be very useful to further improve their prognosis as well as to detect other problems that may cause a significant deterioration in their health-related quality of life (HRQoL). Cure models provide novel statistical tools to better estimate the long-term survival rate for cancer and to identify characteristics that are differentially associated with a short or long-term prognosis. The aim of this study will be to investigate the long-term prognosis of CRC patients, characterise long-term CRC survivors and their HRQoL, and demonstrate the utility of statistical cure models to analyse survival and other associated factors in these patients.MethodsThis is a single-centre, ambispective, observational follow-up study in a cohort of n = 1945 patients with CRC diagnosed between 2006 and 2013. A HRQoL sub-study will be performed in the survivors of a subset of n = 485 CRC patients for which baseline HRQoL data from the time of their diagnosis is already available. Information obtained from interviews and the clinical records for each patient in the cohort is already available in a computerised database from previous studies. This data includes sociodemographic characteristics, family history of cancer, comorbidities, perceived symptoms, tumour characteristics at diagnosis, type of treatment, and diagnosis and treatment delay intervals. For the follow-up, information regarding local recurrences, development of metastases, new tumours, and mortality will be updated using hospital records. The HRQoL for long-term survivors will be assessed with the EORTC QLQ-C30 and QLQ-CR29 questionnaires.An analysis of global and specific survival (competitive risk models) will be performed. Relative survival will be estimated and mixture cure models will be applied. Finally, HRQoL will be analysed through multivariate regression models.DiscussionWe expect the results from this study to help us to more accurately determine the long-term survival of CRC, identify the needs and clinical situation of long-term CRC survivors, and could be used to propose new models of care for the follow-up of CRC patients.

Plasma soluble human leukocyte antigen G predicts the long-term prognosis in patients with colorectal cancer.

BackgroundColorectal cancer (CRC) is the third most common tumor in the world. It is crucial to further screen for indicators that are strictly related to long-term prognosis. Human leukocyte antigen G (HLA-G) is closely involved in tumor development. This study aims to evaluate the long-term predictive value of soluble HLA-G (sHLA-G) in CRC through a double-center retrospective study.MethodsPatients who underwent radical CRC surgery in two hospitals from April 2010 to March 2015 were included. Baseline data of the patients were collected. The patients’ preoperative baseline plasma sHLA-G level was detected. According to whether they survived during five years of follow-up, these patients were divided into two groups. Univariate and multivariate analysis were used to find factors associated with survival. The receiver operation curve (ROC) was performed to analyze the relationship between sHLA-G level and five-year survival, and the cutoff value was obtained. The baseline data and follow-up results of the two groups of patients were compared, and the Kaplan-Meier survival curve was used to analyze the difference in the long-term prognosis of the two groups of patients.ResultsA total of 1,037 cases were included and followed up for more than five years. Three hundred two cases (29.1%) died during the five-year follow-up. The baseline data of the survival group and the death group showed that the baseline level of sHLA-G in the survival group was significantly lower than the death group (41.4±16.9 vs. 64.7±23.2, P<0.05). Univariate and multivariate analyses suggest that age, differentiation, family history, TNM stage, and baseline sHLA-G levels are important factors affecting the survival of CRC patients. The area under ROC of sHLA-G with five-year survival is 0.766, and the cutoff value is 50.8 U/mL. The specificity at this point is 78.1%, and the sensitivity is 72.3%. The Kaplan-Meier survival curve showed that the five-year prognosis of patients in the low-level group was better than that in the high-level group.ConclusionsLower baseline sHLA-G level predicts better prognosis during a five-year follow-up in colorectal cancer patients.

Abstract 4012: Small RNA-sequencing identifies a microRNA signature predictive of response to FOLFOX-based adjuvant therapy in stage II and III colorectal cancer

Abstract Purpose: Current NCCN guidelines for identifying high-risk stage II/III colorectal cancer (CRC) who may benefit from FOLFOX-based adjuvant chemotherapy remain inadequate. While stage III CRC patients often receive six months of oxaliplatin-based therapy following radical surgery, such treatments are frequently toxic and do not benefit all patients. The use of adjuvant chemotherapy in stage II CRC patients is even more controversial. Hence, identification of high-risk CRC patients with the highest likelihood to benefit from such treatments is of paramount clinical importance. Since microRNAs (miRNAs) have emerged as key functional players and important disease biomarkers, using genomewide miRNA expression profiling, we explored their potential as predictive biomarkers of therapeutic response in CRC. Experimental design: Small RNA-sequencing was performed in a cohort of stage II/III CRC patients who received, at least 6 months of FOLFOX-based therapy (n=71; 30 with recurrence, and 41 without recurrence). Identification of differentially expressed miRNAs was done using DESeq2, and biomarker prioritization using LASSO-Cox's proportional hazards model and AUC (area under the curve) analysis, using recurrence-free survival (RFS) as an outcome. The miRNA-signature was validated by using miRCURY LNA miRNA assays in three, independent patient cohorts of tissue (fresh frozen and FFPE) and serum specimens obtained from stage II/III CRC patients (n=91, 77 and 82, respectively). Univariate and multivariate Cox proportional hazard models were used to evaluate the performance of the miRNA classifier, in conjunction with known clinicopathological risk factors and the microsatellite instability (MSI) status. Results: The small RNA-expression profiling led to the identification of a 13-gene miRNA classifier that significantly predicted recurrence free survival (HR: 2.72, 95% CI: 1.96-3.76, p&amp;lt;0.0001) with an AUC of 0.90 (95% CI: 0.83-0.97). This classifier was successfully validated in two tissue cohorts, with impressive AUCs of 0.78 (95% CI: 0.64-0.90, fresh frozen cohort) and 0.86 (95% CI: 0.69-1.00, FFPE cohort), respectively. Importantly, our miRNA signature yielded an impressive AUC of 0.73 (95% CI: 0.60-0.88), even in the preoperative serum specimens from CRC patients. Multivariate analyses revealed that our miRNA classifier was the only independent predictor of response to FOLFOX-based treatment in stage II and III CRC patients. Conclusions: We report a novel miRNA-based classifier, which robustly predicts response to FOLFOX-based adjuvant chemotherapy in stage II/III CRC patients. Validation of this classifier in pre-operative serum provides an attractive opportunity to explore its potential for disease monitoring during the longitudinal follow-up in CRC patients. Citation Format: Raju Kandimalla, Uthra Balaji, Jinghua Gu, Marta Mendiola, Francesc Balaguer, Luis Bujanda, Joan Maurel, Jaime Feliu, Ajay Goel. Small RNA-sequencing identifies a microRNA signature predictive of response to FOLFOX-based adjuvant therapy in stage II and III colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4012.

Plasma microRNA Levels Combined with CEA and CA19-9 in the Follow-Up of Colorectal Cancer Patients.

Colorectal cancer (CRC) ranks among the most common cancers worldwide. Surgical removal remains the best strategy for treatment of resectable tumors. An important part of caring for patients after surgery is monitoring for early detection of a possible relapse of the disease. Efforts are being made to improve the sensitivity and specificity of routinely used carcinoembryonic antigen (CEA) with the use of additional biomarkers such as microRNAs. The aim of our study was to evaluate the prognostic potential of microRNAs and their use as markers of disease recurrence. The quantitative estimation of CEA, CA19-9, and 22 selected microRNAs (TaqMan Advanced miRNA Assays) was performed in 85 paired (preoperative and postoperative) blood plasma samples of CRC patients and in samples taken during the follow-up period. We have revealed a statistically significant decrease in plasma levels for miR-20a, miR-23a, miR-210, and miR-223a (p = 0.0093, p = 0.0013, p = 0.0392, and p = 0.0214, respectively) after surgical removal of the tumor tissue. A statistically significant relation to prognosis (overall survival; OS) was recorded for preoperative plasma levels of miR-20a, miR-21, and miR-23a (p = 0.0236, p = 0.0316, and p =0.0271, respectively) in a subgroup of patients who underwent palliative surgery. The best discrimination between patients with favorable and unfavorable outcomes was achieved by a combination of CEA, CA19-9 with miR-21, miR-20a, and miR-23a (p < 0.0001). The use of these microRNAs for early disease recurrence detection was affected by a low specificity in comparison with CEA and CA19-9. CEA and CA19-9 had high specificity but low sensitivity. Our results show the benefit of combining currently used standard biomarkers and microRNAs for precise prognosis estimation.

Is There a Role for Primary Care in the Follow-Up of Colorectal Cancer Patients? The Case of a Portuguese University Hospital

Background: In Portugal, colorectal cancer is the second most common type of cancer. With the increasing number of cancer survivors, follow-up is perceived as a chronic disease, with a significant impact on hospital care. Objective: To characterize colorectal patients in follow-up at Centro Hospitalar Lisboa Norte, EPE, and to determine the profile of economic resources consumed as well as the consultation workload. Materials and Methods: We characterized colorectal patients in follow-up at Centro Hospitalar Lisboa Norte, EPE, registered from 2008 until 2013 and the profile of economic resources consumed. Results: The Department of Oncology is responsible for 56.2% of colorectal patients’ follow-up. In this study, only 0.4% of cases had follow-up secured in primary care, which translates to a significant impact in terms of resources allocation and consultation management, especially if we consider that 41% of patients are in follow-up for longer than 3 years. The average annual adjusted cost of follow-up per patient is EUR 539.09. Patients who were alive on 31 January 2014 had generated 2,930 follow-up hospital appointments per year, representing 12% of the total number of oncology appointments reported in 2013. Discussion and Conclusions: The follow-up of colorectal cancer patients is associated with significant hospital resource allocation and physicians’ time consumption. Other follow-up models might emerge as an alternative to traditional hospital-centered follow-up, such as the shared-care follow-up, which requires a multidisciplinary and survivor-centered approach, ensuring that information and communication are shared between settings with a clear definition of responsibilities, a survivor care plan, and mechanisms for future referencing when justified.

Post-pulmonary metastasectomy prognosis after curative resection for colorectal cancer.

PurposeWe aimed to compare disease-free survival after pulmonary metastasectomy to that after hepatic metastasectomy, and to identify prognostic factors after pulmonary metastasectomy.ResultsBetween 2005 and 2015, 129 patients underwent resection of isolated metachronous lung metastases from colorectal cancer. Three-year DFS after pulmonary metastasectomy was similar to that after hepatic metastasectomy (50.7% vs. 45.5%, respectively; p=0.58). Rectal cancer (hazard ratio [HR]: 2.04, 95% confidence interval [CI]: 1.09–3.79; p=0.03) and ≥2 metastases (HR: 2.17, 95% CI: 1.28–3.68; p=0.004) were independent adverse risk factors associated with disease-free survival after pulmonary metastasectomy on multivariate analysis. Three-year DFS for colon vs. rectal cancer patients was 72.5% vs. 42.6%, respectively (p=0.04). The number of lung metastases was an independent risk factor for DFS after pulmonary metastasectomy in rectal cancer patients.Patients and MethodsPatients who underwent lung metastasectomy after curative resection of colorectal cancers were investigated. Disease-free survival (DFS) after pulmonary metastasectomy was compared to that after hepatic metastasectomy, which has a relatively well-known prognosis. Multivariate Cox proportional hazards analysis was performed to identify clinical variables predictive of survival after pulmonary metastasectomy.ConclusionsDisease-free survival rates after resection of lung vs. liver metastases arising from colorectal cancers are similar. However, lung metastases specifically from rectal cancers produce poorer DFS rates. Primary tumor location must be considered for pulmonary metastasis treatment and follow-up in colorectal cancer patients.

A Study of Hypermethylated Circulating Tumor DNA as a Universal Colorectal Cancer Biomarker.

Circulating tumor DNA (ctDNA) has emerged as a good candidate for tracking tumor dynamics in different cancer types, potentially avoiding repeated tumor biopsies. Many different genes can be mutated within a tumor, complicating procedures for tumor monitoring, even with highly sensitive next-generation sequencing (NGS) strategies. Droplet-based digital PCR (dPCR) is a highly sensitive and quantitative procedure, allowing detection of very low amounts of circulating tumor genetic material, but can be limited in the total number of target loci monitored. We analyzed hypermethylation of 3 genes, by use of droplet-based dPCR in different stages of colorectal cancer (CRC), to identify universal markers for tumor follow-up. Hypermethylation of WIF1 (WNT inhibitory factor 1) and NPY (neuropeptide Y) genes was significantly higher in tumor tissue compared to normal tissue, independently of tumor stage. All tumor tissues appeared positive for one of the 2 markers. Methylated ctDNA (MetctDNA) was detected in 80% of metastatic CRC and 45% of localized CRC. For samples with detectable mutations in ctDNA, MetctDNA and mutant ctDNA (MutctDNA) fractions were correlated. During follow-up of different stage CRC patients, MetctDNA changes allowed monitoring of tumor evolution. These results indicate that MetctDNA could be used as a universal surrogate marker for tumor follow-up in CRC patients, and monitoring MetctDNA by droplet-based dPCR could avoid the need for monitoring mutations.

Application of Circulating Tumor DNA as a Non-Invasive Tool for Monitoring the Progression of Colorectal Cancer.

BackgroundLiquid biopsy has been proposed to be a promising noninvasive tool to obtain information on tumor progression. Through a clinical observation of a case series of 6 consecutive patients, we aim to determine the value of circulating tumor DNA (ctDNA) for monitoring the tumor burden during the treatment of colorectal cancer (CRC).Materials and MethodsWe used capture sequencing of 545 genes to identify somatic alternations in primary tumor tissues of the six CRC patients who underwent radical surgery and in 23 plasma samples collected at serial time points. We compared the mutation patterns and variant allele frequencies (VAFs) between the matched tissue and the plasma samples and evaluated the potential advantage of using ctDNA as a better tumor load indicator to detect disease relapse over carcinoembryonic antigen (CEA), cancer antigen (CA) 19–9 and imaging studies.ResultsWe identified low-frequency mutations with a mean VAF of 0.88% (corresponding to a mean tumor burden of 0.20ng/mL) in the preoperative plasmas of four patients with locally advanced CRC and a subset of mutations shared by their primary tumors. The tumor loads appeared a sudden decrease upon surgery or other adjuvant treatments and then generally maintained at low levels (0.092ng/mL) until disease recurred. ctDNA increased by 13-fold when disease relapsed in one patient while the CEA and CA 19–9 levels remained normal. In this patient, all six somatic mutations identified in the preoperative plasma were detected in the recrudescent plasma again, with five mutations showing allele fraction increase.ConclusionsWe described a multi-time-point profile of ctDNA of CRC patients during the course of comprehensive treatment and observed a correlation of ctDNA level with the clinically evaluated tumor progression. This demonstrated a new strategy by analyzing the heterogeneous ctDNA to evaluate and monitor the tumor burden in the treatment and follow-up of CRC patients, with potentially better potency than conventional biomarkers.

Hypermethylated circulating DNA detection using picoliter droplet-based PCR in colorectal cancer.

622 Background: Circulating tumor DNA (ctDNA) is thoroughly investigated as a surrogate biomarker of tumor follow-up, in different cancer types, such as colorectal cancer (CRC). Droplet-based digital PCR (ddPCR) is a highly sensitive and also quantitative method for detection of very low amount of ctDNA. Since many different genes can be mutated within a specific tumor type and also wide mutation spectrum can occur within a specific gene, procedures for ctDNA monitoring can be time consuming and need to be improved for a routinely use. To overcome these drawbacks, we characterized the methylation status of 3 genes frequently hypermethylated in CRC to identify universal markers for tumor follow-up. Methods: The characterization of the methylated status of the WIF, NPY and PENK genes in the tumor DNA was performed in 56 CRC of different stages and 45 corresponding plasma samples using droplet-based dPCR, after DNA bisulfite conversion. A two-panels assay (with albumin as a reference) was developed. Methylation level of these 3 genes in tumor tissues was compared to corresponding normal tissues (n = 22) and plasma samples (MetctDNA). To validate, plasma samples of additional 91 patients were analyzed for the presence of ctDNA both by the characterization of KRAS, BRAF, TP53 and PIK3CA mutations (MutctDNA) and of MetctDNA, at various stages of their follow-up, and 9 of them had MetctDNA assessment during treatment follow-up. Results: All tumor samples were positive for WIF1 and/or NPY markers. Hypermethylation of these two genes was significantly higher in tumor tissue compared to normal, independently of the tumor stage (p &lt; 0.0001). MetctDNA could be detected in 75% of metastatic CRC patients and 24% of localized CRC patients (stage 1 to 3). MetctDNA and MutctDNA fractions were strongly correlated (R2 &gt; 0.9, p &lt; 0.0001). During follow-up, MetctDNA levels changes allowed monitoring of tumor evolution in different stages CRC patients. Conclusions: These results indicate that determination of MetctDNA by droplet-based dPCR can reach same efficiency than MutctDNA for ctDNA assessment, using only 2 markers, and thus could be considered as a universal surrogate marker of tumor follow-up in CRC patients.

Increased tumor infiltration by mucosal-associated invariant T cells correlates with poor survival in colorectal cancer patients.

The infiltration of tumors by lymphocytes is a prognosis factor in colorectal cancer (CRC). The magnitude and quality of this infiltration have emerged as important component of the clinical outcome in these patients. Specifically, markers associated with functional cell-mediated immunity, i.e., a Th1 immune response, are independent markers of better prognosis, whereas Th17-associated components are deleterious and correlate with poorer survival. Mucosal-associated invariant T (MAIT) cells are a recently described T cell subset with tissue-homing properties. They display a restricted TCR repertoire specific for widely conserved microbial ligands, and display anti-bacterial properties upon release of Th1-like, Th17-like, and/or cytotoxic granules. MAIT-cell-specific transcripts have been found in kidney and brain cancer, but have not been studies in other sites. In this study, we retrospectively analyzed by confocal microscopy the presence of MAIT cells within colorectal tumors as compared with paired healthy tissues. We observed a significant although variable increase, both in density and in proportion of overall tumor-infiltrating T lymphocytes inside the tumors. Importantly, survival curves as well as multivariate analysis showed that patients displaying a higher recruitment of MAIT cells in their tumor, as compared with the neighboring healthy tissue, showed a less favorable clinical outcome. This study suggests that including MAIT-cell-specific markers or transcripts in the analysis of tumor-infiltrating lymphocytes could be a benefit to the diagnosis and follow-up of CRC patients.

Intensified follow-up in colorectal cancer patients using frequent Carcino-Embryonic Antigen (CEA) measurements and CEA-triggered imaging: Results of the randomized “CEAwatch” trial

AimThe value of frequent Carcino-Embryonic Antigen (CEA) measurements and CEA-triggered imaging for detecting recurrent disease in colorectal cancer (CRC) patients was investigated in search for an evidence-based follow-up protocol. MethodsThis is a randomized-controlled multicenter prospective study using a stepped-wedge cluster design. From October 2010 to October 2012, surgically treated non-metastasized CRC patients in follow-up were followed in eleven hospitals. Clusters of hospitals sequentially changed their usual follow-up care into an intensified follow-up schedule consisting of CEA measurements every two months, with imaging in case of two CEA rises. The primary outcome measures were the proportion of recurrences that could be treated with curative intent, recurrences with definitive curative treatment outcome, and the time to detection of recurrent disease. Results3223 patients were included; 243 recurrences were detected (7.5%). A higher proportion of recurrences was detected in the intervention protocol compared to the control protocol (OR = 1.80; 95%-CI: 1.33–2.50; p = 0.0004). The proportion of recurrences that could be treated with curative intent was higher in the intervention protocol (OR = 2.84; 95%-CI: 1.38–5.86; p = 0.0048) and the proportion of recurrences with definitive curative treatment outcome was also higher (OR = 3.12, 95%-CI: 1.25–6.02, p-value: 0.0145). The time to detection of recurrent disease was significantly shorter in the intensified follow-up protocol (HR = 1.45; 95%-CI: 1.08–1.95; p = 0.013). ConclusionThe CEAwatch protocol detects recurrent disease after colorectal cancer earlier, in a phase that a significantly higher proportion of recurrences can be treated with curative intent.

Circulating microRNA Testing for the Early Diagnosis and Follow-up of Colorectal Cancer Patients

Early detection of colorectal cancer (CRC) is key for prevention and the ability to impact long-term survival of CRC patients. However, the compliance rate of recommended colonoscopy for the population aged from 50 to 75years is only 50-75% in the US. A highly sensitive and specific non-invasive test is needed to enhance CRC management. As for late-stage patients, a non-invasive prognostic biomarker is also critical for improving patient treatment protocols. The discovery that non-coding microRNAs (miRNAs) are stable in body fluids such as plasma, serum and exosomes presents the opportunity to develop novel strategies, taking advantage of circulating miRNAs as early diagnostic biomarkers of CRC. The goal of using circulating miRNA-based prognostic biomarkers for CRC patients has been pursued extensively. In this review, we will try to cover the major recent advancements at the frontier of this research area.