Predictive factors of early relapse in UICC stage I-III colorectal cancer patients after curative resection

A systematic review of population-based studies on metachronous metastases of colorectal cancer

BACKGROUND

The occurrence of metachronous metastases (MM) of colorectal (CRC), colon (CC), and rectal (RC) cancer of population-based studies has not been compiled in a systematic review previously.

METHODS

MEDLINE, Embase, and Cochrane Library were searched for primary studies of any design from inception until January 2021 and updated in August 2023 (CRD42021261648). The PRISMA guidelines were adopted, and the Newcastle-Ottawa Quality Assessment Scale used for risk of bias assessment. Outcomes on overall and organ-specific MM were extracted. A narrative analysis followed.

RESULTS

Out of 2143 unique hits, 162 publications were read in full-text and 37 population-based cohort studies published in 1981-2022 were included. Ten studies adopted time-dependent analyses; eight were registry-based and seven had a low risk of bias. Three studies reported 5-year recurrence rate of MM overall of stages I-III; for CRC, it was 20.5%, for CC, it was 18% and 25.6%, and for RC, it was 23%. Four studies reported 5-year recurrence rate of organ-specific MM of stages I-III-for CRC, it was 2.2% and 5.5% for peritoneal metastases and 5.8% for lung metastases and for CC 4.5% for peritoneal metastases. Twenty-seven studies reported proportions of patients diagnosed with MM, but data on the length of follow-up was incomplete and varied widely. Proportions of patients with CRC stages I-III that developed MM overall was 14.4%-26.1% in 10 studies. In relation to the enrollment period, a downward trend may be discernible.

CONCLUSION

Studies adopting a more appropriate analysis were highly heterogeneous, whereas uncertain data of partly inadequate studies may indicate that MM are overall declining.

Evaluating the Role of Methylated Circulating Tumor DNA in Combination With Pathological Prognostic Factors for Predicting Recurrence of Colorectal Cancer

Background

Colorectal cancer (CRC) has a high rate of recurrence, in particular for advanced disease, but prognosis based on staging and pathology at surgery can have limited efficacy. The presence of circulating tumor DNA (ctDNA) at diagnosis could be used to improve the prediction for disease recurrence.

Objectives

To assess the impact of detecting methylated BCAT1/IKZF1 ctDNA at diagnosis in combination with demographic, lifestyle, clinical factors and tumor pathology, to assess predictive value for recurrence.

Design

A retrospective cohort study.

Methods

The cohort included 180 patients (36 with recurrent CRC), who had undergone complete treatment and surveillance for a minimum of 3 years. Participant clinical details and ctDNA methylated BCAT1/IKZF1 results were compared between those with and without recurrence, and cox regression analysis assessed each factor on disease-free survival.

Results

Clinical factors independently associated with reduced disease-free survival included nodal involvement (HR = 3.83, 95% CI 1.56-9.43, P = .003), M1 stage (HR = 4.41, 95% CI 1.18-16.45, P = .027), a resection margin less than 2 mm (HR = 4.60, 95% CI 1.19-17.76, P = .027), perineural involvement (HR = 2.50, 95% CI 1.01-6.17, P = .047) and distal tumors (HR = 3.13, 95% CI 1.07-9.18, P = .037). Methylated BCAT1/IKZF1 was detected in 51.7% (93/180) of pre-treatment plasma samples. When a positive ctDNA finding was considered in combination with these clinical prognostic factors, there was improved predictive power of recurrence for patients with perineural involvement (HR = 4.44, 95% CI 1.92-10.26, P < .001), and it marginally improved the predictive factor for M1 stage (HR = 7.59, 95% CI 2.30-25.07, P = .001) and distal tumors (HR = 5.04, 95% CI 1.88-13.49, P = .001).

Conclusions

Nodal invasion, metastatic disease, distal tumor site, low resection margins and perineural invasion were associated with disease recurrence. Pre-treatment methylated ctDNA measurement can improve the predictive value for recurrence in a subset of patients, particularly those with perineural involvement.

Registration

Australian and New Zealand Clinical Trials Registry #12611000318987.

Impact of regional lymph node metastasis on pulmonary metastasis as the first recurrence site

Little is known about the impact of regional lymph node metastasis (LNM) on the first recurrence sites following curative colorectal cancer (CRC) surgery. The present study aimed to clarify the relationship between regional LNM stratified by N status and the first recurrence pattern in patients with stage I-III CRC. We performed a retrospective analysis of 1181 consecutive patients with stage I-III CRC who underwent curative surgery between 2010 and 2018. The total sample size included 1181 patients who underwent elective stage I-III CRC surgery. Median follow-up time was 60 months, and median time to recurrence was 12 months. Overall, the numbers of liver recurrence and pulmonary recurrence were 94 (7.9%) and 70 (5.9%), respectively. Higher N status was significantly associated with increased risk of pulmonary recurrence (N0 vs. N1a, p = 0.02; N0 vs. N1b, p < 0.01; N0 vs. N2a, p < 0.01; N0 vs. N2b, p < 0.01) and worse pulmonary recurrence-free survival, but not other recurrences. In Non-LNM patients, on the other hand, advanced T status was associated with increased risk of pulmonary recurrence. The regional LNM was strongly associated with pulmonary metastasis as the first recurrence site following stage I-III CRC resection.

Is a less-intensive follow-up for colon cancer in early stages reasonable?

PURPOSE

Patients with colon cancer are usually included in an intensive 5-year surveillance protocol after curative resection, independent of the tumor stage, though early stages have a considerably lower risk of recurrence. The aim of this study was to analyze the adherence to an intensive follow-up and the risk of recurrence in patients with colon cancer in UICC stages I and II.

METHODS

In this retrospective study, we assessed patients who underwent resection for colon cancer in UICC stages I and II between 2007 and 2016. Data were collected on demographics, tumor stages, therapy, surveillance, recurrent disease, and oncological outcome.

RESULTS

Of the 232 included patients, 43.5% (n = 101) reached the 5-year follow-up disease-free. Seven (7.5%) patients in stage UICC I and sixteen (11.5%) in UICC II had a recurrence, with the highest risk in patients with pT4 (26.3%). A metachronous colon cancer was detected in four patients (1.7%). The therapy of recurrence was intended to be curative in 57.1% (n = 4) of UICC stage I and in 43.8% (n = 7) of UICC stage II, but only in one of seven patients over 80 years. 44.8% (n = 104) of the patients were lost to follow-up.

CONCLUSION

A postoperative surveillance in patients with colon cancer is important and recommended as a recurrent disease can be treated successfully in many patients. However, we suggest that a less intensive surveillance protocol is reasonable for patients with colon cancer in early tumor stages, especially in UICC stage I, as the risk of recurrent disease is low. With elderly and/or frail patients in a reduced general condition, who will not endure further specific therapy in case of a recurrence, the performance of the surveillance should be discussed: we recommend a significant reduction or even renunciation.

What is the Risk for Peritoneal Metastases and Survival Afterwards in T4 Colon Cancers?

BACKGROUND

Patients with T4 colon adenocarcinomas have an increased risk of peritoneal metastases (PM) but the histopathologic risk factors for its development are not well-described.

OBJECTIVE

The purpose of this study was to determine factors associated with PM, time to recurrence, and survival after recurrence among patients with T4 colon cancer.

PATIENTS AND METHODS

Patients with pathologic T4 colon cancer who underwent curative resection from 2005 to 2017 were identified from a prospectively maintained institutional database and classified by recurrence pattern: (a) none - 68.8%; (b) peritoneal only - 7.9%; (c) peritoneal and extraperitoneal - 9.9%; and (d) extraperitoneal only - 13.2%. Associations between PM development and patient, primary tumor, and treatment factors were assessed.

RESULTS

Overall, 151 patients were analyzed, with a median follow-up of 66.2 months; 27 patients (18%) developed PM (Groups B and C) and 20 (13%) patients recurred at non-peritoneal sites only (Group D). Median time to developing metastases was shorter for Groups B and C compared with Group D (B and C: 13.7 months; D: 46.7 months; p = 0.022). Tumor deposits (TDs) and nodal stage were associated with PM (p < 0.05), and TDs (p = 0.048) and LVI (p = 0.015) were associated with additional extraperitoneal recurrence. Eleven (41%) patients with PM underwent salvage surgery, and median survival after recurrence was associated with the ability to undergo cytoreduction (risk ratio 0.20, confidence interval 0.06-0.70).

CONCLUSION

PM risk after resection of T4 colon cancer is independently associated with factors related to lymphatic spread, such as N stage and TDs. Well-selected patients can undergo cytoreduction with long-term survival. These findings support frequent postoperative surveillance and aggressive early intervention, including cytoreduction.

Early Versus Late Recurrence in Rectal Cancer: Does Timing Matter?

BACKGROUND

The definition of early recurrence (ER) in rectal cancer is unclear, and the association of ER with post-recurrence survival (PRS) is poorly described. We therefore sought to identify if time to recurrence (TTR) is associated with PRS.

METHODS

We reviewed all curative-intent resections of nonmetastatic rectal cancer from 2003 to 2018 in our institutional registry within an NCI-Designated Comprehensive Cancer Center. Clinicopathologic data at diagnosis and first recurrence were collected and analyzed. ER was pre-specified at < 24 months and late recurrence (LR) at ≥ 24 months. PRS was evaluated by the Kaplan-Meier method and Cox proportional hazards modeling.

RESULTS

At a median follow-up of 53 months, 61 out of 548 (11.1%) patients undergoing resection experienced recurrence. Median TTR was 14 months (IQR 10-18) with 45 of 61 patients (74%) classified as ER. There were no significant baseline differences between patients with ER and LR. Most recurrences were isolated to the liver (26%) or lung (31%), and 16% were locoregional. ER was not associated with worse PRS compared to LR (P > 0.99). On multivariable analysis, detection of recurrence via workup for symptoms, CEA > 10 ng/mL at recurrence, and site of recurrence were independently associated with PRS.

CONCLUSION

ER is not associated with PRS in patients with resected rectal cancer. Symptomatic recurrences and those accompanied by CEA elevations are associated with worse PRS, while metastatic disease confined to the liver or lung is associated with improved PRS. Attention should be directed away from TTR and instead toward determining therapy for patients with treatable oligometastatic disease.

An 11-gene signature for the prediction of systemic recurrences in colon adenocarcinoma

Background

Prognosis varies among patients within the same colon adenocarcinoma (COAD) stage, indicating the need for reliable molecular markers to enable individualized treatment. This study aimed to investigate gene signatures that can be used for better prognostic prediction of COAD.

Methods

Gene-expression profiles of COAD patients were obtained from the Gene Expression Omnibus database (n = 332) and The Cancer Genome Atlas database (n = 431). The relationship between gene signature and relapse-free survival was analysed in the training set (n = 93) and validated in the internal validation set (n = 94) and external validation sets (n = 145 and 431).

Results

Overall, 11 genes (N-myc downstream regulated gene 1 [NDRG1], fms-like tyrosine kinase 1 [FLT1], lipopolysaccharide binding protein [LBP], fatty acid binding protein 4 [FABP4], adiponectin gene [ADIPOQ], angiotensinogen gene [AGT], activin A receptor, type II-like kinase 1 [ACVRL1], CC chemokine ligand 11 [CCL11], cell division cycle 42 [CDC42], T-cell receptor alpha variable 9_2 [TRAV9_2], and proopiomelanocortin [POMC]) were identified by univariable and least absolute shrinkage and selection operator (LASSO) Cox regression analyses. Based on the risk-score model, the patients were grouped into the high-risk or low-risk groups using the median risk score as the cut-off. The area under the curve (AUC) values for 1-, 3-, and 5-year recurrence were 0.970, 0.849, and 0.859, respectively. Patients in the high-risk group had significantly poorer relapse-free survival than did those in the low-risk group. The predictive accuracy of the 11-gene signature was proven in the validation sets. Our gene signature showed better predictive performance for 1-, 3-, and 5-year recurrence than did the other four models.

Conclusions

The 11-gene signature showed good performance in predicting recurrence in COAD. The accuracy of the signature for prognostic classification requires further confirmation.

The Latest Update of Prognostic Factors of Stage III Colon Cancer Who Underwent Curative Operation and Postoperative Adjuvant Chemotherapy

This study aimed to explore the predicting factor of the poor prognosis of stage III colon cancer. Adjuvant chemotherapy for stage III colon cancer has become popular. However, the choice of the optimal adjuvant chemotherapy regimen still remains unclear. A total of 135 patients with stage III colon cancer, treated with postoperative adjuvant chemotherapy from January 2007 to December 2012 at the Kitasato University East Hospital, were reviewed retrospectively in terms of clinicopathologic characteristics associated with survival and recurrence (median observation: 61 months). We used a multivariate Cox hazards model to identify independent prognostic factors in stage III colon cancer. Of the 135 patients, 38 had recurrence. Five-year overall survival was 83.9%, while 3-year recurrence-free survival was 72.8%. Oxaliplatin-containing adjuvant chemotherapy was almost exclusively applied to stage IIIB colon cancer. Univariate analysis of the negative prognostic factors were N2 (P = 0.0004); operation time (P = 0.0346); tumor size (P = 0.0092); depth of invasion (P = 0.005); histology (P = 0.0403); infiltration type (P &lt; 0.0001); lymphatic permeation (ly3, P = 0.0001); and vascular permeation (v3, P = 0.0005). On multivariate analysis, the independent prognostic factors for relapse-free survival were v3 (P = 0.032) and N2 (P = 0.0216). Combination of the prognostic factors clearly stratified prognosis of stage III colon cancer patients, and those with either factor positive had a poor prognosis despite administration of adjuvant chemotherapy. Both v3 and pN2 may be critical prognostic factors in stage III colon cancer with adjuvant chemotherapy. This information would elucidate areas of concern in the present therapeutic strategy in stage III colon cancer.

Identifying Stage II Colorectal Cancer Recurrence Associated Genes by Microarray Meta-Analysis and Building Predictive Models with Machine Learning Algorithms

Background

Stage II colorectal cancer patients had heterogeneous prognosis, and patients with recurrent events had poor survival. In this study, we aimed to identify stage II colorectal cancer recurrence associated genes by microarray meta-analysis and build predictive models to stratify patients' recurrence-free survival.

Methods

We searched the GEO database to retrieve eligible microarray datasets. The microarray meta-analysis was used to identify universal recurrence associated genes. Total samples were randomly divided into the training set and the test set. Two survival models (lasso Cox model and random survival forest model) were trained in the training set, and AUC values of the time-dependent receiver operating characteristic (ROC) curves were calculated. Survival analysis was performed to determine whether there was significant difference between the predicted high and low risk groups in the test set.

Results

Six datasets containing 651 stage II colorectal cancer patients were included in this study. The microarray meta-analysis identified 479 recurrence associated genes. KEGG and GO enrichment analysis showed that G protein-coupled glutamate receptor binding and Hedgehog signaling were significantly enriched. AUC values of the lasso Cox model and the random survival forest model were 0.815 and 0.993 at 60 months, respectively. In addition, the random survival forest model demonstrated that the effects of gene expression on the recurrence-free survival probability were nonlinear. According to the risk scores computed by the random survival forest model, the high risk group had significantly higher recurrence risk than the low risk group (HR = 1.824, 95% CI: 1.079-3.084, p = 0.025).

Conclusions

We identified 479 stage II colorectal cancer recurrence associated genes by microarray meta-analysis. The random survival forest model which was based on the recurrence associated gene signature could strongly predict the recurrence risk of stage II colorectal cancer patients.

Defining early recurrence in patients with resected primary colorectal carcinoma and its respective risk factors

PURPOSE

There is no evidence-based definition of early recurrence following resection of colorectal cancer. The purpose of this study is to define a point that discriminates between early and late recurrence in patients who have undergone colorectal cancer resection with curative intent and to analyze associated risk factors.

METHODS

A retrospective single-center cohort study was performed at a university hospital recognized as a comprehensive cancer center, specializing in colorectal cancer surgery. Patient data were retrieved from a prospectively maintained institutional database. Included patients underwent resection for primary, non-metastatic colorectal carcinomas with curative intent between 1995 and 2010. Aims of the study were (1) to define the optimal cut-off point of recurrence-free survival based on overall survival using a minimum p value approach and (2) to identify patterns of initial recurrence and putative risk factors for early recurrence using regression models.

RESULTS

Recurrence was diagnosed in 412 of 1893 patients. Statistical analysis suggested that a recurrence-free survival of 16 months could be used to distinguish between early and late recurrence based on overall survival (p < 0.001). Independent risk factors for early recurrence included advanced pT categories (pT3,4/ypT3,4) and positive lymph node status (pN+/ypN+). Early recurrence was independent of site of recurrence and was associated with worse prognosis.

CONCLUSIONS

Recurrence of colorectal carcinoma within 16 months after primary treatment should be labeled as "early." Tumor categories pT3,4/ypT3,4 and positive lymph node status pN+/ypN+ are predictive of early recurrence.

The JPJDF has Synergistic Effect with Fluoropyrimidine in the Maintenance Therapy for Metastatic Colorectal Cancer

Background:

Maintenance chemotherapeutic regimen with low toxicity is needed for metastatic colorectal cancer. A recent patent has been issued on the spleen-strengthening and detoxification prescription (JPJDF), a traditional Chinese herbal medicinal formula with anti-angiogenesis effect. The clinical effect of JPJDF on the maintenance treatment of advanced colorectal cancer has not been evaluated.

Objective:

This study aims to evaluate the effectiveness and safety of JPJDF in combination with fluoropyrimidine compared to fluoropyrimidine alone as maintenance therapy for metastatic colorectal cancer.

Methods:

We applied a prospective, randomized, double-blinded, single center clinical study design. A total of 137 patients with advanced colorectal cancer were recruited. Patients received either Fluoropyrimidine (Flu-treated group, n = 68), or Fluoropyrimidine plus JPJDF (Flu-F-treated group, n = 69) as maintenance treatment after 6-cycle of FOLFOX4 or FOLFORI induction treatment. The primary endpoints were Progression-Free Survival (PFS) and Overall Survival (OS). The secondary endpoints were safety, Performance Status (PS) score and other symptoms.

Results:

The endpoint of disease progression was observed in 91.7% of patients. The PFS was 5.0 months and 3.0 months in the Flu-F-treated and Flu-treated groups, respectively. The OS was 15.0 months and 9.0 months in the Flu-F-treated and Flu-treated groups, respectively. Some common symptoms, such as hypodynamia, anepithymia, dizziness and tinnitus and shortness of breath, were improved in the Flu-F-treated group. There was no significant difference in the common adverse reactions between the two groups.

Conclusion:

JPJDF and fluoropyrimidine have synergistic effect in the maintenance treatment of mCRC.

Factors associated with colon cancer early, intermediate and late recurrence after surgery for stage I-III: A 5-year prospective study

OBJECTIVE

To identify factors associated with early, intermediate or late recurrence colon cancer recurrence.

METHODS

A total of 1,732 consecutive patients with colon cancer were recruited and followed for a period of 5 years. Recurrence at 1 year (early), from 1 to 2 (early), from 2 to 3 (intermediate) and from 3 to 5 years (late) was the main outcome measures.

RESULTS

Predictors of early recurrence (AUC (95% CI):0.74 (0.70-0.78) were as follows: TNM stage II and III, more than one type of invasion, haemoglobin <10 g/dl, residual tumour (R1), ASA IV, log odds of positive lymph nodes ratio ≥-0.53, perforation, neoadjuvant chemotherapy, infectious complications within 1 year and CEA pre- and post-intervention. These factors remained significant for predicting intermediate (AUC [95% CI]: 0.72 [0.67-0.77]) and late (AUC [95% CI]: 0.68 [0.63-0.74]) recurrence, except for ASA class, log lymph node ratio, perforation and neoadjuvant chemotherapy. Additionally, laterality (left) and medical complications up to 2 years were significant.

CONCLUSIONS

These risk factors show good predictive ability of early, intermediate and late recurrence, confirming factors established by guidelines and adding some others. They could serve to provide more appropriate and accurate treatment and follow-up tailored to patient characteristics.

Defining and predicting early recurrence in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy

BACKGROUND

The definition of "early recurrence (ER)" after rectal cancer surgery is currently unclear.

OBJECTIVE

To determine an evidence-based cut-off to distinguish early and late recurrence (LR) for patients with rectal cancer and compare the clinicopathological factors between the two groups.

METHODS

Patients who underwent neoadjuvant chemoradiotherapy (nCRT) and radical resection for locally advanced rectal cancer were included. A minimum p-value approach was used to evaluate the optimal cut-off value of recurrence-free survival to divide the patients into ER and LR groups based on overall survival. A logistic regression model was used to assess risk factors for ER.

RESULTS

A total of 763 patients were included, of which 167 (21.9%) experienced recurrence. The optimal cut-off value of recurrence-free survival to differentiate between ER (n = 125, 74.9%) and LR (n = 42, 25.1%) was 24 months (P = 0.000001). The median postrecurrence survival of ER and LR was 12 months and 22 months, respectively (p = 0.028). The most common recurrent sites in patients with ER and LR were lung metastases, the incidence of liver metastases, however, differed considerably in ER and LR (27.2% vs 9.5%, P = 0.019). Risk factors including elevated preoperative carcinoembryonic antigen (CEA), higher ypTNM stage, positive circumferential resection margin (CRM), and perineural invasion were significantly associated with ER.

CONCLUSION

A recurrence-free interval of 24 months is the optimal cut-off value for defining ER versus LR. Elevated preoperative CEA, higher ypTNM staging, positive CRM, and perineural invasion were associated with ER of locally advanced rectal cancer.

Early postoperative recurrences for colon cancer: Results from a Pakistani rural cohort

Objectives

We conducted this study to determine the factors associated with early postoperative recurrence in colon cancer patients treated with curative intent.

Methods

All consecutive patients who underwent curative resection for colon cancer between January 2014 and December 2016 were reviewed. All patients received either adjuvant chemotherapy or follow-up at the Bannu Institute of Nuclear Medicine Oncology and Radiotherapy (BINOR). The patients lived in rural areas of southern Khyber Pakhtunkhwa province.

Results

We enrolled 72 patients, 28 of whom experienced a postoperative recurrence within 2 years (early recurrence). In univariate analysis, postoperative early relapse was significantly correlated with advanced age (>60 years, p = 0.030), nodal status (p = 0.012), pathological stage (p = 0.013), number of nodes removed (p < 0.001), and perineural invasion (p = 0.044). In multivariate analysis, age more than 60 years (p = 0.031) and fewer than 12 lymph nodes removed (p = 0.003) were independent predictors for early recurrence. The liver was the most common site of recurrence (42.8%) in this study.

Conclusion

Our results showed that advanced age and the removal of fewer than 12 lymph nodes during surgery were significant predictors for early postoperative recurrence. Identification of high-risk patients during follow-up with enhanced therapeutic modalities can improve disease-free survival.

A signature predicting relapse based on integrated analysis on relapse-associated alternative mRNA splicing in I-III rectal cancer

Researches focusing on the effects of alternative splicing (AS) on relapse of rectal cancer is little and signature based on the AS is blank. In this study, bioinformatic analysis was performed to identify and analyze the relapse-associated ASs, a signature was also constructed. In conclusion, 829 relapse-associated ASs of 676 mRNA were identified. 603 proteins with 2119 interactions were involved in the PPI (protein-protein interactions) network. 43 relapse-associated ASs and 64 SFs (splicing factors) with 160 interactions were indicated. Finally, we built a robust signature to predict the relapse of I-III rectal cancer with a high AUC (0.98) of ROC at 1 year. Based on the ASs involved in the signature, 4 molecular subgroups that could distinguish the relapse rate in diverse groups were identified. Our research provided an overview of relapse-associated ASs in I-III rectal cancer.

Chemotherapeutic Effectiveness of Combining Cetuximab for Metastatic Colorectal Cancer Treatment: A System Review and Meta-Analysis

This meta-analysis used the database including PubMed, Medline, Cochrane Library, CNKI, Chinese-Cqvip, and Wanfang for randomized controlled trials (RCTs) to investigate the clinical effectiveness for combining cetuximab treatment with chemotherapy for treating metastatic colorectal cancer (mCRC). A total of 12 RCTs involved 7,108 patients with mCRC were included. The patients received chemotherapy with (3,521 cases) or without cetuximab (3,587 cases). Outcomes were overall survival (OS), progression-free survival (PFS), disease control rate (DCR), overall response rate (ORR), odd ratio (OR), and risk ratio (HR). Our results showed that the chemotherapy alone group has shorter OS, PFS, and ORR than the chemotherapy plus cetuximab group, with significant differences (PFS:HR = 0.77, 95% CI = 0.72–0.82, P < 0.00001; OS:HR = 0.88, 95% CI = 0.79–0.99, P = 0.03; ORR:OR = 1.79, 95% CI = 1.30–2.47; P = 0.0003). Results of subgroup analysis showed that cetuximab treatment prolonged PFS and OS in KRAS wild-type patients, with statistically significant differences (PFS:HR = 0.79, 95% CI = 0.65–0.95, P = 0.01; OS:HR = 0.85, 95% CI = 0.74–0.98, P = 0.02). Combining cetuximab with chemotherapy, the PFS and OS of wild-type KRAS patients and the ORR of all patients were significantly improved.

Efficacy and toxicity of adjuvant chemotherapy on colorectal cancer patients: how much influence from the genetics?

We studied the predictive value for response and toxicity of functional polymorphisms in genes involved in the oxaliplatin/fluorouracil pathway in colorectal cancer patients. One hundred and twenty-seven (127) patients were treated with curative intended surgery followed by adjuvant chemotherapy with FOLFOX (fluorouracil, leucovorin and oxaliplatin) regimen. The median age was 65.53 (27-80) years (66.9% male, 59.1% rectum). The median follow-up was 8.5 years (IQR, 4.1-9.4). At the end of follow-up, 59 patients (46.5%) had relapsed or died in the whole study population. We did find that XRCC1GG genotype is associated with a higher risk of developing haematologic toxicity. Furthermore, we report a significant association of the TS 3'UTR 6 bp/6 bp polymorphism and the XRCC1 rs25487 with a higher risk of developing anaemia and diarrhoea, respectively. On the other hand, none of the studied polymorphisms showed clinically relevant association with disease-free survival and overall survival or early failure to adjuvant FOLFOX therapy.

Development and validation of a novel epigenetic signature for predicting prognosis in colon cancer

Epigenetic factors play a critical role in carcinogenesis by imparting a distinct feature to the chromatin architecture. The present study aimed to develop a novel epigenetic signature for evaluating the relapse-free survival of colon cancer patients. Public microarray datasets were acquired from the Gene Expression Omnibus databases: GSE39582, GSE17538, GSE33113, and GSE37892 set. Patients from GSE39582 set were randomized 1:1 into training and internal validation series. Patients were divided into high-risk and low-risk groups in training series based on a set of 11 epigenetic factors (p < .001). The good reproducibility for the prognostic value of the epigenetic signature was confirmed in the internal validation series (p < .001), external validation series (a combination of GSE17538 set, GSE33113 set, and GSE37892 set; p = .018), and entire series (p < .001). Furthermore, a nomogram, which integrated the epigenetic signature, pathological stage, and postoperative chemotherapy, was developed based on the GSE39582 set. The time-dependent receiver operating characteristic curve at 1 year demonstrated that the comprehensive signature presented superior prognostic value than the pathological stage. In conclusion, an epigenetic signature, which could be utilized to divide colon cancer patients into two groups with significantly different risk of relapse, was established. This biomarker would aid in identifying patients who require an intensive follow-up and aggressive therapeutic intervention.

HSPB1 rs2070804 polymorphism is associated with the depth of primary tumor

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer in the world. Genome-wide association studies are a powerful method to analyze the status of single-nucleotide polymorphisms (SNPs) in specific genes. Heat shock proteins (HSPs) were found to be involved in the cancer progression and chemoresistance. However, there is still no further study about polymorphisms of HSP beta-1 (HSPB1) in colorectal cancer. We proposed the SNP of HSPB1 may be correlated with the progression and metastasis in colon cancer.

METHODS

We recruited 379 colorectal cancer patients and categorized as four stages following the UICC TNM system. Then, we selected tagging SNPs of HSPB1 by 10% minimum allelic frequency in Han Chinese population from the HapMap database and analyze with the Chi-square test.

RESULTS

We demonstrated the association of HSPB1 genetic polymorphisms rs2070804 with tumor depth with colorectal cancer. But, there is a lack of association between HSPB1 genetic polymorphisms and colorectal cancer invasion, recurrence or metastasis.

CONCLUSIONS

The polymorphisms of HSPB1 seemed to change the tumor behavior of colorectal cancer. HSPB1 rs2070804 polymorphism is associated with the depth of the primary tumor. But, there is no further correlation with other to the clinical parameters such as cancer invasiveness, local recurrence, or distant metastasis.

Transcriptome profiling reveals an integrated mRNA-lncRNA signature with predictive value of early relapse in colon cancer

The purpose of our study was to develop a multigene signature based on transcriptome profiles of both mRNAs and lncRNAs to identify a group of patients who are at high risk of early relapse in stages II-III colon cancer. Firstly, propensity score matching was conducted between patients in early relapse group and long-term survival group from GSE39582 training series (N = 359) and patients were matched 1:1. Global transcriptome analysis was then performed between the paired groups to identify tumor specific mRNAs and lncRNAs. Finally, using LASSO Cox regression model, we built a multigene early relapse classifier incorporating 15 mRNAs and three lncRNAs. The prognostic and predictive accuracy of the signature was internally validated in 102 colon cancer patients and externally validated in other 241 patients. In the training set, patients with high risk score were more likely to suffer from relapse than those with low risk score (HR: 2.67, 95% CI: 2.07-3.46, P < 0.001). The results were validated in the internal validation set (HR: 2.23, 95% CI: 1.23-3.78, P = 0.003) and external validation (HR 1.88, 95% CI 1.42-2.48; P < 0.001) set. Time-dependent receiver operating curve at 1 year showed that the integrated mRNA-lncRNA signature [area under curve (AUC) = 0.742] had better prognostic accuracy than AJCC TNM stage (AUC = 0.615) in the entire 702 patients. In addition, survival decision curve analyses at 12 months revealed a good clinical usefulness of the integrated mRNA-lncRNA signature. In conclusion, we successfully developed an integrated mRNA-lncRNA signature that can accurately predict early relapse.

miR-148a inhibits early relapsed colorectal cancers and the secretion of VEGF by indirectly targeting HIF-1α under non-hypoxia/hypoxia conditions

Vascular endothelial growth factor (VEGF) is correlated with angiogenesis and early relapse of colorectal cancer (CRC). This study investigated the role of miR‐148a in the regulation of VEGF/angiogenesis and early relapse of CRC. We established a stable clone with miR‐148a expression in HCT116 and HT29 cell lines and created a hypoxic condition by using CoCl₂ to determine the underlying mechanism of miR‐148a. The effects of miR‐148a on the phosphoryl‐ERK (pERK)/hypoxia‐inducible factor‐1α (HIF‐1α)/VEGF pathway were evaluated through Western blotting and the inhibitory effect of miR‐148a on angiogenesis was demonstrated through a tube formation assay. Sixty‐three CRC tissues (28 early relapse and 35 non‐early relapse) were analysed to assess the relationship between miR‐148a and HIF‐1α/VEGF. The protein expression of pERK/HIF‐1α/VEGF in HCT116 and HT29 cells was significantly decreased by miR‐148a (all P < 0.05). The protein expression of VEGF/HIF‐1α was strongly inversely associated with the expression of miR‐148a in the 63 CRC tissue samples (all P < 0.05). Tube formation assay demonstrated that miR‐148a significantly obliterated angiogenesis. miR‐148a suppresses VEGF through down‐regulation of the pERK/HIF‐1α/VEGF pathway and might lead to the inhibition of angiogenesis; miR‐148a down‐regulation increased the early relapse rate of CRC. This demonstrates that miR‐148a is a potential diagnostic and therapeutic target.

The Use of Circulating Tumor DNA for Prognosis of Gastrointestinal Cancers

Gastrointestinal cancers, including oesophageal, gastric and colorectal cancers (CRC) have high rates of disease recurrence despite curative resection. There are a number of recent studies that have investigated the use of circulating tumor DNA (ctDNA) for prognostic value in these cancers. We reviewed studies that had been published prior to March 2018 that assessed the prognostic values of ctDNA in patients with oesophageal and gastric cancers, gastrointestinal stromal tumors (GIST) and CRC. We identified 63 eligible clinical studies that focussed on recurrence and survival. Studies assessed investigated various ctDNA biomarkers in patients with different stages of cancer undergoing surgical resection, chemotherapy and no treatment. For oesophageal squamous cell carcinoma and oesophageal adenocarcinoma, methylation of certain genes such as APC and DAPK have been highlighted as promising biomarkers for prognostication, but these studies are limited and more comprehensive research is needed. Studies focusing on gastric cancer patients showed that methylation of ctDNA in SOX17 and APC were independently associated with poor survival. Two studies demonstrated an association between ctDNA and recurrence and survival in GIST patients, but more studies are needed for this type of gastrointestinal cancer. A large proportion of the literature was on CRC which identified both somatic mutations and DNA methylation biomarkers to determine prognosis. ctDNA biomarkers that identified somatic mutations were more effective if they were personalized based on mutations found in the primary tumor tissue, but ctDNA methylation studies identified various biomarkers that predicted increased risk of recurrence, poor disease free survival and overall survival. While the use of non-invasive ctDNA biomarkers for prognosis is promising, larger studies are needed to validate the clinical utility for optimizing treatment and surveillance strategies to reduce mortality from gastrointestinal cancers.

Reduced miR-433 expression is associated with advanced stages and early relapse of colorectal cancer and restored miR-433 expression suppresses the migration, invasion and proliferation of tumor cells in vitro and in nude mice

The expression of microRNA (miR-433) is altered in various types of human cancer. The present study analyzed the prognostic and biological value of miR-433 expression in colorectal cancer using reverse transcription-quantitative polymerase chain reaction in 125 colorectal tissue specimens (including a test cohort of 40 cases of paired colorectal cancer and adjacent normal mucosae and a confirmation cohort of 85 cases of stage I–III colorectal cancer). In vitro and nude mouse xenograft experiments were subsequently used to assess the effects of miR-433 expression on the regulation of colorectal cancer cell proliferation, adhesion, migration, and invasion. The data indicated that miR-433 expression was significantly downregulated in colorectal cancer tissues in the test and confirmation patient cohorts and that low miR-433 expression was associated with advanced tumor stage and early relapse. Furthermore, the restoration of miR-433 expression was able to significantly inhibit the proliferation of tumor cells by inducing G1-S cell cycle arrest, suppressing cyclinD1 and CDK4 expression, and markedly inhibited the migratory and invasive capacities of tumor cells in vitro. The restoration of miR-433 expression or liposome-based delivery of miR-433 mimics suppressed the growth of colorectal cancer cell xenografts in nude mice. In conclusion, miR-433 may be a putative tumor suppressor in colorectal cancer, and the detection of low miR-433 expression will be investigated in further studies as a putative biomarker for the detection of early relapse in patients with colorectal cancer.

Predictive Nomogram for Recurrence of Stage I Colorectal Cancer After Curative Resection

BACKGROUND

Patients with stage I colorectal cancer (CRC) have excellent prognosis after curative surgery. However, approximately 5% to 10% of patients experience recurrence and have a poor prognosis. Because the incidence of stage I CRC is increasing with active screening programs worldwide, a more accurate and easy-to-use predictive tool for recurrence is becoming more important. This study aimed to develop a predictive nomogram for recurrence in stage I CRC.

PATIENTS AND METHODS

A total of 1538 patients who underwent curative surgery for stage I CRC were enrolled. Predictive factors for recurrence were determined by multivariate Cox regression model and were used to develop a predictive nomogram. This model was internally validated, and performance was evaluated through calibration plots.

RESULTS

The cumulative recurrence rate at 5 years after surgery for stage I CRC was 5.3%. In multivariate Cox analysis, independent predictors of recurrence were tumor location at rectum, pT2 stage, and presence of lymphovascular invasion. The 5-year recurrence rate was significantly different depending on the number of risk factors (0.7% for 0, 5.8% for 1, and 9.7% for ≥ 2 risk factors). On this basis, a nomogram for recurrence-free survival was developed and internally validated. The concordance index of the nomogram was 0.71, and the performance was acceptable.

CONCLUSION

We developed and internally validated a nomogram that can predict postoperative recurrence in stage I CRC patients. This nomogram may be used to more accurately stratify the risk of recurrence and to perform personalized postoperative surveillance in stage I CRC patients.

A robust gene signature for the prediction of early relapse in stage I-III colon cancer

Colon cancer patients experiencing early relapse consistently exhibited poor survival. The aim of our study was to develop an mRNA signature that can help to detect early relapse cases in stage I-III colon cancer. Public microarray datasets of stage I-III colon cancer samples were extracted from the Gene Expression Omnibus database. Propensity score matching analysis was performed between patients in the early relapse group and the long-term survival group from GSE39582 discovery series (N = 386), and patients were 1 : 1 matched. Global mRNA expression changes were then analyzed between the paired groups to identify the differentially expressed genes. Lasso Cox regression modeling analysis was conducted for the selection of prognostic mRNA. Fifteen mRNA were finally identified to build an early relapse classifier. With specific risk score formula, patients were classified into a high-risk group and a low-risk group. Relapse-free survival was significantly different between the two groups in every series, including discovery [hazard ratio (HR): 2.547, 95% confidence interval (CI): 1.708-3.797, P < 0.001)], internal validation (HR: 5.146, 95% CI: 1.968-13.457, P < 0.001), and external validation (HR: 1.977, 95% CI: 1.295-3.021, P < 0.001) sets of patients. Time-dependent receiver-operating characteristic at 1 year suggested more prognostic accuracy of the classifier [area under curve (AUC = 0.703)] than the American Joint Commission on Cancer tumor-node-metastasis staging system (AUC = 0.659) in all 951 patients. In conclusion, we developed a robust mRNA signature that can effectively classify colon cancer patients into groups with low and high risks of early relapse. This mRNA signature may help select high-risk colon cancer patients who require more aggressive therapeutic intervention.

Do High-risk Features Support the Use of Adjuvant Chemotherapy in Stage II Colon Cancer? A Turkish Oncology Group Study

Background

A high-risk group of patients with stage II colon cancer has been identified by the results of studies in Western populations. The aim of this study was to investigate the prognostic factors of adjuvant chemotherapy in Turkish patients with stage II colon cancer.

Methods

A total of 554 stage II colon cancer patients were retrospectively enrolled in the study. Three hundred fifty-three patients had received adjuvant chemotherapy (5-FU-LV, FOLFOX or FLOX) and 201 had received no adjuvant chemotherapy. T4 tumor stage, lymphovascular invasion, perineural invasion, bowel obstruction and/or perforation, <12 harvested lymph nodes, and poor differentiation were defined as high-risk factors.

Results

The median age of the patients was 62 years (range 26–88). The median disease-free survival (DFS) was 58.1 months (95% CI, 47.6 months to 68.5 months) in the non-treatment group and has not been reached in the treatment group (P <0.01). In univariate analysis, patient age >60 years and T4 tumor stage were statistically significant factors that affected DFS as poor prognostic factors. Adjuvant chemotherapy reduced the risk of recurrence with statistical significance (P <0.01). In multivariate analysis, patient age >60 years and T4 tumor stage were independent risk factors affecting DFS. In addition, adjuvant chemotherapy was an independent favorable prognostic factor for DFS (P <0.01).

Conclusions

Clinical and pathological risk factors in patients with stage II colon cancer may be different in the Turkish population compared to other populations. Further prospective studies in colon cancer are needed to understand the differences in biology and risk factors between races.

Molecular correlates and prognostic value of tmTNF-α expression in colorectal cancer of 5-Fluorouracil-Based Adjuvant Therapy

Transmembrane tumor necrosis factor-α (tmTNF-α) is known to induce the activation of NF-κB to protect tumor cells. Upregulation of tmTNF-α leads to resistance to apoptosis and induces drug resistance in breast cancer. However, the expression of tmTNF-α in colorectal cancer (CRC) and its association with clinical outcome in CRC have remained unclear. In this study, we examined the tmTNF-α expression in CRC by immunohistochemistry and western blotting, assessed the prognostic value of tmTNF-α related to the recurrence/metastasis and survival of stage II/III CRC by the Kaplan-Meier survival curve and Cox regression model, and also explored the role of tmTNF-α expression on the chemotherapeutic efficacy of 5-Fluorouracil by flow cytometry assay and cell counting kit-8 (CCK-8) in vitro. Overall, we found that 77 (78.6%) out of 98 patients exhibited higher tmTNF-α expression in the CRC tissues comparing with the adjacent tissues. The tmTNF-α expression was correlated with Differentiation (P = 0.019), TNM stage (P = 0.039), Lymph nodes metastasis (P = 0.024) and Lymphovascular invasion (P = 0.027) but not related with Age (P = 0.617), Gender (P = 0.625), Tumor location (P = 0.138), Perforation/Obstruction (P = 1.000), Depth of invasion (P = 0.327), and microsatellite instability status (P = 0.150). The prognostic analyses showed that high tmTNF-α expression patients was significantly associated with decreased Disease-Free Survival (P = 0.0209) and Overall Survival (P = 0.0163). CCK-8 results suggested that the tmTNF-α influenced the chemotherapeutic effect of 5-Fluorouracil on colon cancer cells. Altogether, these data indicated the stageII/III CRC patients with high tmTNF-α expression were more likely to have a worse prognosis than patients with low tmTNF-α expression and tmTNF-α may influence the chemotherapeutic effect of 5-Fluorouracil. The mechanism for these observations warrants further study.

Time to local recurrence as a predictor of survival in unrecetable gastric cancer patients after radical gastrectomy

Local recurrence is common after radical surgery. However, the factors that contribute to survival after local recurrence remain unclear. In this retrospective study we analyzed the relationship between time to recurrence and survival after recurrence in 74 patients with locally recurrent gastric cancer. All patients received palliative radiotherapy with or without chemotherapy. The patients were divided into two groups according to the time between gastrectomy and local recurrence: early local recurrence (ELR, < 12 months after primary surgery), and late local recurrence (LLR, ≥12 months after primary surgery). The median overall survival (OS) time was 15 months for patients with ELR and 25 months for LLR patients. Univariate and multivariate analysis revealed that time to local recurrence was significantly associated with OS after local recurrence (P = 0.001). The hazard ratio of ELR compared with LLR patients was 0.442 (95% confidence interval: 0.264-0.741). These results indicate that early local recurrence predicted poor prognosis in gastric cancer patients with unresectable local recurrence.

Prognostic and Oncologic Significance of Perineural Invasion in Sporadic Colorectal Cancer

BACKGROUND

The presence of perineural invasion (PNI) in colorectal cancer (CRC) indicates a more aggressive phenotype, resulting in a poor prognosis. The aims of this study were to evaluate the oncologic outcome of PNI+ tumors and to investigate whether PNI status affects patient survival.

METHODS

The study retrospectively enrolled 3807 patients from a single institution who underwent surgery for colorectal adenocarcinoma between January 2006 and December 2010. The patients were classified into two groups based on PNI status: PNI+ and PNI-.

RESULTS

The PNI+ group included 565 patients (14.8 %) and had significantly more involved circumferential resection margins (p = 0.001) and a more advanced TNM stage (p = 0.001) than the PNI- group. Compared with the PNI- group, the PNI+ group had worse 5-year overall survival (65 vs. 88 %; p = 0.001) and 5-year disease-free survival (63 vs. 85 %; p = 0.001). Among PNI+ patients with stage IIA disease, those who received adjuvant therapy had significantly greater 5-year overall survival than those who did not (89.3 vs. 50.8 %; p = 0.001). In multivariate analyses, PNI+ was an independent negative prognostic factor for 5-year overall survival (hazard ratio [HR] 1.518, 95 % confidence interval [CI] 1.175-1.961; p = 0.001) and 5-year disease-free survival (HR 1.495, 95 % CI 1.237-1.806; p = 0.001).

CONCLUSIONS

PNI positivity is an independent predictor of aggressive behavior and unfavorable prognosis in CRC. Further evaluation is needed to confirm the impact of PNI status on survival in stage IIA CRC.

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

Background

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

Methods

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

Results

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

Conclusions

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

Blood CEA levels for detecting recurrent colorectal cancer

BACKGROUND

Testing for carcino-embryonic antigen (CEA) in the blood is a recommended part of follow-up to detect recurrence of colorectal cancer following primary curative treatment. There is substantial clinical variation in the cut-off level applied to trigger further investigation.

OBJECTIVES

To determine the diagnostic performance of different blood CEA levels in identifying people with colorectal cancer recurrence in order to inform clinical practice.

SEARCH METHODS

We conducted all searches to January 29 2014. We applied no language limits to the searches, and translated non-English manuscripts. We searched for relevant reviews in the MEDLINE, EMBASE, MEDION and DARE databases. We searched for primary studies (including conference abstracts) in the Cochrane Central Register of Controlled Trials (CENTRAL), in MEDLINE, EMBASE, and the Science Citation Index & Conference Proceedings Citation Index - Science. We identified ongoing studies by searching WHO ICTRP and the ASCO meeting library.

SELECTION CRITERIA

We included cross-sectional diagnostic test accuracy studies, cohort studies, and randomised controlled trials (RCTs) of post-resection colorectal cancer follow-up that compared CEA to a reference standard. We included studies only if we could extract 2 x 2 accuracy data. We excluded case-control studies, as the ratio of cases to controls is determined by the study design, making the data unsuitable for assessing test accuracy.

DATA COLLECTION AND ANALYSIS

Two review authors (BDN, IP) assessed the quality of all articles independently, discussing any disagreements. Where we could not reach consensus, a third author (BS) acted as moderator. We assessed methodological quality against QUADAS-2 criteria. We extracted binary diagnostic accuracy data from all included studies as 2 x 2 tables. We conducted a bivariate meta-analysis. We used the xtmelogit command in Stata to produce the pooled estimates of sensitivity and specificity and we also produced hierarchical summary ROC plots.

MAIN RESULTS

In the 52 included studies, sensitivity ranged from 41% to 97% and specificity from 52% to 100%. In the seven studies reporting the impact of applying a threshold of 2.5 µg/L, pooled sensitivity was 82% (95% confidence interval (CI) 78% to 86%) and pooled specificity 80% (95% CI 59% to 92%). In the 23 studies reporting the impact of applying a threshold of 5 µg/L, pooled sensitivity was 71% (95% CI 64% to 76%) and pooled specificity 88% (95% CI 84% to 92%). In the seven studies reporting the impact of applying a threshold of 10 µg/L, pooled sensitivity was 68% (95% CI 53% to 79%) and pooled specificity 97% (95% CI 90% to 99%).

AUTHORS' CONCLUSIONS

CEA is insufficiently sensitive to be used alone, even with a low threshold. It is therefore essential to augment CEA monitoring with another diagnostic modality in order to avoid missed cases. Trying to improve sensitivity by adopting a low threshold is a poor strategy because of the high numbers of false alarms generated. We therefore recommend monitoring for colorectal cancer recurrence with more than one diagnostic modality but applying the highest CEA cut-off assessed (10 µg/L).

Practice Guideline for the Surveillance of Patients After Curative Treatment of Colon and Rectal Cancer

Current evidence suggests improved rates of curative secondary treatment following identification of recurrence among patients who participate in a surveillance program after initial curative resection of colon or rectal cancer. The newer data show that surveillance CEA, chest and liver imaging,and colonoscopy can also improve survival through early diagnosis of recurrence; thus, these modalities are now included in the current guideline. Although the optimum strategy of surveillance for office visits, CEA, chest and liver imaging, and colonoscopy is not yet defined, routine surveillance does improve the detection of recurrence that can be resected with curative intent. Recommended surveillance schedules are shown in Table 4. However, the factors to be considered when recommending surveillance include underlying risk for recurrence, patient comorbidity, and the ability to tolerate major surgery to resect recurrent disease or palliative chemotherapy, performance status, physiologic age, preference, and compliance. The success of surveillance for early detection of curable recurrence will depend on patient and provider involvement to adhere to the surveillance schedule and avoid unnecessary examination. It should be noted that, after curative resection of colorectal cancer, patients are still at risk for other common malignancies(lung, breast, cervix, prostate) for which standard screening recommendations should be observed and measures to maintain general health (risk reduction for cardiovascular disease, eg, cessation of smoking, control of blood pressure and diabetes mellitus, balanced diet, regular exercise and sleep, and flu vaccines) should be recommended.

Time to local recurrence as a prognostic factor in patients with rectal cancer

AIMS

Survival after the local recurrence of rectal cancer is influenced by several factors. The aim of this study was to ascertain whether the time interval from primary surgery for rectal cancer to local recurrence diagnosis has any impact on survival.

METHODS

Population-based data was collected from the Swedish Colorectal Cancer Registry. 7410 patients were operated with radical abdominal surgery for rectal cancer during the period 1995-2002. Of these, 386 (5%) developed a local recurrence as a first event. The patients were divided into two groups: early local recurrence (ELR), diagnosed <12 months after primary surgery, and late local recurrence (LLR), diagnosed ≥12 months after primary surgery. Kaplan-Meier curves and hazard ratios were calculated for survival analyses. Survival was calculated from the date of the local recurrence diagnosis to death or end of follow-up.

RESULTS

Ninety-five patients had ELR and 291 patients LLR. Median time to local recurrence was 1.7 (0.1-7.9) years. Patients with a stage III primary tumour and non-irradiated patients were more common in the ELR compared with the LLR group. Factors that influenced survival were age at diagnosis of local recurrence (p < 0.001), stage of primary tumour (p = 0.027), and surgical resection of local recurrence (p < 0.001). Time to diagnosis of local recurrence had no influence on survival.

CONCLUSIONS

No difference in survival from date of diagnosis of local recurrence was seen between patients with ELR and patients with LLR. All patients with local recurrence should therefore be assessed for potential curative surgery, disregarding time to local recurrence.

Development of a claims-based algorithm to identify colorectal cancer recurrence

PURPOSE

To examine the validity of claims data to identify colorectal cancer (CRC) recurrence and determine the extent to which misclassification of recurrence status affects estimates of its association with overall survival in a population-based administrative database.

METHODS

We calculated the accuracy of claims data relative to medical records from one large tertiary hospital to identify CRC recurrence. We estimated the effect of misclassifying recurrence on survival by applying these findings to the linked Surveillance, Epidemiology, and End Results-Medicare data.

RESULTS

Of 174 eligible CRC patients identified through medical records, 32 (18.4%) had a recurrence. A claims-based algorithm of secondary malignancy codes yielded a sensitivity of 81% and specificity of 99% for identifying recurrence. Agreement between data sources was almost perfect (kappa: 0.86). In a model unadjusted for misclassification, CRC patients with recurrence were 3.04 times (95% confidence interval: 2.92-3.17) more likely to die of any cause than those without recurrence. In the corrected model, CRC patients with recurrence were 3.47 times (95% confidence interval: 3.06-4.14) more likely to die than those without recurrence.

CONCLUSIONS

Identifying recurrence in CRC patients using claims data is feasible with moderate sensitivity and high specificity. Future studies can use this algorithm with Surveillance, Epidemiology, and End Results-Medicare data to study treatment patterns and outcomes of CRC patients with recurrence.

The small-molecule compound BM-1197 inhibits the antiapoptotic regulators Bcl-2/Bcl-xL and triggers apoptotic cell death in human colorectal cancer cells

Small molecule BH3 mimetics comprise a promising new chemotherapeutic strategy for treating relapsed or chemoresistant cancer. In this study, we investigated the cellular mechanism of action by which BM-1197, a Bcl-xL/Bcl-2 dual inhibitor, triggers apoptosis in a panel of colorectal cancer (CRC) lines. Using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, we determined that BM-1197 inhibited CRC cell growth in a concentration- and time-dependent manner. The 50 % inhibitory concentration (IC50) values for the most sensitive cell lines, SW620 and SW480, ranged from 0.07 to 1.10 μM in response to a 72-h treatment. In CRC cells, BM-1197 induced apoptotic death without affecting the expression of Bcl-2 family proteins. However, BM-1197 effectively triggered a conformational change in Bax, releasing Bim from Bcl-xL by disrupting the interaction between Bcl-xL and Bak/Bax. Compared with the control group, BM-1197 treatment significantly increased the fraction of SW480 cells in the sub-G1 phase, the apoptosis rate, and cellular internucleosomal DNA fragmentation. The proapoptotic activity was associated with cytochrome c release, caspase-3 activation, and PARP-1 cleavage. Collectively, BM-1197 effectively suppressed the growth of the human CRC cell line SW480 by inducing mitochondria-dependent apoptotic cell death. These data have specific implications for the in vivo analysis and clinical evaluation of BM-1197 in CRC.

Determinants of recurrence after intended curative resection for colorectal cancer

Despite intended curative resection, colorectal cancer will recur in ∼45% of the patients. Results of meta-analyses conclude that frequent follow-up does not lead to early detection of recurrence, but improves overall survival. The present literature shows that several factors play important roles in development of recurrence. It is well established that emergency surgery is a major determinant of recurrence. Moreover, anastomotic leakages, postoperative bacterial infections, and blood transfusions increase the recurrence rates although the exact mechanisms still remain obscure. From pathology studies it has been shown that tumors behave differently depending on their location and recur more often when micrometastases are present in lymph nodes and around vessels and nerves. K-ras mutations, microsatellite instability, and mismatch repair genes have also been shown to be important in relation with recurrences, and tumors appear to have different mutations depending on their location. Patients with stage II or III disease are often treated with adjuvant chemotherapy despite the fact that the treatments are far from efficient among all patients, who are at risk of recurrence. Studies are now being presented identifying subgroups, in which the therapy is inefficient. Unfortunately, only few of these facts are implemented in the present follow-up programs. Therefore, further research is urgently needed to verify which of the well-known parameters as well as new parameters that must be added to the current follow-up programs to identify patients at risk of recurrence.

Clinical characteristics of second primary cancer in colorectal cancer patients: the impact of colorectal cancer or other second cancer occurring first

Background

Due to improvements in early detection, treatment, and supportive care, the number of colorectal cancer (CRC) survivors is increasing; therefore, careful attention should always be paid to the second primary cancer (SPC) in treating these CRC patients. The present study attempts to determine the correlation and clinical aspects of CRC to other cancers in patients suffering from SPC involving CRC.

Methods

From January 2002 and June 2010, 1,679 cancer cases, CRC was accompanied by SPC in 89 patients (5.3%), including 16 (18%) synchronous and 73 (82%) metachronous SPC patients. These patients were subsequently classified into two groups: the first group had CRC diagnosed first as CRC first (CRCF); and the second group had another type of cancer diagnosed before the diagnosis of CRC as other cancer first (OCF). Of these 73 patients, 22 (30.1%) were in the group of CRCF, whereas 51 (69.9%) were in the group of OCF. Patients’ clinicopathological characteristics and clinical outcomes were analyzed and compared between the two groups.

Results

There was a significant difference in the sites of cancers between the two groups: 14 (27.5%) patients in the OCF group had gastric cancer, compared to one (4.5%) patient in the CRCF group (P = 0.026). Although there was no difference of hepatitis B virus (HBV) or hepatitis C virus (HCV) carriers between the OCF and CRCF groups (P = 0.165), there were six (27.3%) CRC patients with hepatocellular carcinoma (HCC) in the CRCF group, which was significantly higher than the two (3.9%) patients in the OCF group (P = 0.003). Furthermore, the cancer-specific survival rate of the CRCF patient group was significantly higher than that of the OCF patient group (P = 0.036).

Conclusions

In this retrospective analysis, gastric cancer patients compared to other secondary cancers were at a higher risk of developing subsequent CRC as SPC; alternatively, patients with CRC were at a higher risk of developing HCC as SPC subsequently, no matter whether patients were HBV or HCV carriers. Therefore, careful attention should always be paid to the possibility of secondary CRC to construct effective surveillance when treating cancer patients.

Predictive factors and the prognosis of recurrence of colorectal cancer within 2 years after curative resection

PURPOSE

Because predicting recurrence intervals and patterns would allow for appropriate therapeutic strategies, we evaluated the clinical and pathological characteristics of early and late recurrences of colorectal cancer.

METHODS

Patients who developed recurrence after undergoing curative resection for colorectal cancer stage I-III between January 2000 and May 2006 were identified. Early recurrence was defined as recurrence within 2 years after primary surgery of colorectal cancer. Analyses were performed to compare the clinicopathological characteristics and overall survival rate between the early and late recurrence groups.

RESULTS

One hundred fifty-eight patients experienced early recurrence and 64 had late recurrence. Multivariate analysis revealed that the postoperative elevation of carbohydrate antigen 19-9 (CA 19-9), venous invasion, and N stage correlated with the recurrence interval. The liver was the most common site of early recurrence (40.5%), whereas late recurrence was more common locally (28.1%), or in the lung (32.8%). The 5-year overall survival rates for early and late recurrence were significantly different (34.7% vs. 78.8%; P < 0.001). Survival rates after the surgical resection of recurrent lesions were not different between the two groups.

CONCLUSION

Early recurrence within 2 years after surgery was associated with poor survival outcomes after colorectal cancer recurrence. An elevated postoperative CA 19-9 level, venous invasion, and advanced N stage were found to be significant risk factors for early recurrence of colorectal cancer.

Promoter CpG island methylation of RET predicts poor prognosis in stage II colorectal cancer patients

Improved prognostic stratification of patients with TNM stage II colorectal cancer (CRC) is desired, since 20-30% of high-risk stage II patients may die within five years of diagnosis. This study was conducted to investigate REarranged during Transfection (RET) gene promoter CpG island methylation as a possible prognostic marker for TNM stage II CRC patients. The utility of RET promoter CpG island methylation in tumors of stage II CRC patients as a prognostic biomarker for CRC related death was studied in three independent series (including 233, 231, and 294 TNM stage II patients, respectively) by using MSP and pyrosequencing. The prognostic value of RET promoter CpG island methylation was analyzed by using Cox regression analysis. In the first series, analyzed by MSP, CRC stage II patients (n = 233) with RET methylated tumors had a significantly worse overall survival as compared to those with unmethylated tumors (HRmultivariable = 2.51, 95%-CI: 1.42-4.43). Despite a significant prognostic effect of RET methylation in stage III patients of a second series, analyzed by MSP, the prognostic effect in stage II patients (n = 231) was not statistically significant (HRmultivariable = 1.16, 95%-CI 0.71-1.92). The third series (n = 294), analyzed by pyrosequencing, confirmed a statistically significant association between RET methylation and poor overall survival in stage II patients (HRmultivariable = 1.91, 95%-CI: 1.04-3.53). Our results show that RET promoter CpG island methylation, analyzed by two different techniques, is associated with a poor prognosis in stage II CRC in two independent series and a poor prognosis in stage III CRC in one series. RET methylation may serve as a useful and robust tool for clinical practice to identify high-risk stage II CRC patients with a poor prognosis. This merits further investigation.

Up-regulation of miR-224 promotes cancer cell proliferation and invasion and predicts relapse of colorectal cancer

BACKGROUND

MicroRNAs (miRNAs) are small, non-coding RNAs that can function as oncogenes or tumor suppressors in human cancer. Abnormally expressed miR-224 was found to play a fundamental role in several types of cancer. The aim of this study was to investigate the prognostic and biological values of miR-224 in colorectal cancer (CRC).

METHODS

Quantitative RT-PCR (qRT-PCR) was used to evaluate expression levels of miR-224. The postoperative survival rate was analyzed with Kaplan-Meier method. The roles of miR-224 in cell proliferation, migration and invasion were analyzed with pre-miR-224 transfected cells. In addition, the regulation of SMAD4 by miR-224 was evaluated by qRT-PCR, Western blotting and luciferase reporter assays.

RESULTS

In the present study, we demonstrated that miR-224 was significantly up-regulated in CRC tissue samples and associated with disease relapse and a relative poorer disease-free survival rate. Moreover, ectopic expression of miR-224 potently promoted tumor cell proliferation, migration and invasion in vitro. Furthermore, the over-expression of miR-224 in CRC cell lines decreased SMAD4 expression at the translational level and decreased SMAD4-driven luciferase-reporter activity.

CONCLUSIONS

Our data suggest that miR-224 could play an oncogenic role in the cellular processes of CRC and represent a novel biomarker for tumor relapse of CRC patients.

Clinical significance of microRNA-148a in patients with early relapse of stage II stage and III colorectal cancer after curative resection

Development of robust prognostic/predictive biomarkers in patients with colorectal cancer (CRC) is imperative for advancing treatment strategies for this disease. We aimed to determine whether expression status of microRNAs might be a simple and reliable biomarker to detect postoperative early relapse in patients with CRC after radical resection. We used microRNA arrays and identified that microRNA-148a (miRNA-148a) had substantially different expression levels in early and nonearly relapsed stage II and III CRC tissues. The validation study, which included 55 early relapsed patients and 55 nonearly relapsed patients, further confirmed overexpression of miRNA-148a in nonearly relapsed samples. Subsequently, we explored whether the serum level of miRNA-148a can be used to predict early CRC recurrence. The in vitro and in vivo effects of miRNA-148a were examined by cell proliferation, migration, and invasion, as well as cell cycles, and xenograft in null mice. Last, miRNA-148a was investigated as a potential biomarker for identifying early relapse. Cellular studies demonstrated that the overexpression of miRNA-148a inhibited colon cancer cell proliferation and migration but not invasion. The cell cycle studies also revealed that miRNA-148a caused an accumulation of the G2 population. Moreover, lower levels of miRNA-148a expression were associated with significantly shorter disease-free survival rates and poorer overall survival rates. This study showed that miRNA-148a can inhibit tumorigenesis and reduce the early recurrence of CRC. These findings suggest that miRNA-148a may have potential clinical applications for predicting the early relapse of patients with CRC after radical resection.

Early recurrence in patients undergoing curative surgery for colorectal cancer: is it a predictor for poor overall survival?

PURPOSE

This study evaluated the prognostic value of early recurrence in patients who have undergone curative resection for colorectal cancer.

METHODS

A total of 1,159 consecutive patients who underwent curative resection for non-metastatic colorectal cancer from December 1998 to December 2007 were reviewed. The predictive factors for early recurrence postoperatively and the prognostic factors were analyzed.

RESULTS

Of the 1,159 patients, postoperative recurrence was identified in 280 (24.1%) patients, and 96 (34.3%) of the 280 patients with recurrence were designed as early recurrence (less than 1 year postoperatively). In multivariate analysis, tumor location, tumor diameter, number of retrieved lymph nodes, and lymphovascular invasion were the independent predictors for early recurrence. The early recurrence group had a significantly lower overall survival rate than that of the non-early recurrence group for both colon cancer (P < 0.001) and rectal cancer (P < 0.001). The overall survival rate for stage III tumors significantly differed between the early and non-early recurred patients (P < 0.001), whereas the rate did not differ between the patients with stage II tumors (P = 0.364). In multivariate analysis, early recurrence was an independent predictor for unfavorable overall survival. Moreover, differentiation, N category, and postoperative chemotherapy were the independent predictors for overall survival for the patients with both early and overall recurrence.

CONCLUSION

Poor survival was associated with early postoperative recurrence for patients who underwent curative resection for colorectal cancer. The use of adjuvant chemotherapy prolonged the survival of patients, irrespective of the interval of recurrence.