Detection of carcinoembryonic antigen messenger RNA-expressing cells in peripheral blood 7 days after curative surgery is a novel prognostic factor in colorectal cancer

Prognostic factors in patients with high-risk stage II colon cancer after curative resection: a post hoc analysis of the JFMC46-1201 trial

PURPOSE

The goal of the current study was to identify prognostic factors for disease-free survival (DFS) and overall survival (OS) in high-risk stage II colon cancer.

METHODS

The subjects were patients with histologically confirmed stage II colon cancer undergoing R0 resection who met at least one of the following criteria: T4, perforation/penetration, poorly differentiated adenocarcinoma, mucinous carcinoma, and < 12 examined lymph nodes. Patients self-selected surgery alone or a 6-month oral uracil and tegafur plus leucovorin (UFT/LV) regimen. Serum CEA mRNA at ≥ 24 h after surgery and < 2 weeks after registration was also examined as a potential prognostic factor for stage II colon cancer. This study is registered with UMIN-CTR (protocol ID: UMIN000007783).

RESULTS

1880 were included in the analysis to identify prognostic factors for DFS and OS in patients with high-risk stage II colon cancer. In multivariate analyses, gender, depth of tumor invasion, extent of lymph node dissection, number of examined lymph nodes, and postoperative adjuvant chemotherapy (POAC) emerged as significant independent prognostic factors for DFS. Similarly, multivariate analysis showed that age, gender, depth of tumor invasion, perforation/penetration, extent of lymph node dissection, number of examined lymph nodes, and POAC were significant independent prognostic factors for OS. Univariate analyses showed no significant difference in DFS or OS for CEA mRNA-positive and mRNA-negative cases.

CONCLUSION

This study showed that gender, depth of tumor invasion, extent of lymph node dissection, number of examined lymph nodes, and lack of use of POAC were significant independent prognostic factors in stage II colon cancer.

A meta-analysis of the value of circulating tumor cells in monitoring postoperative recurrence and metastasis of colorectal cancer

Objective

Circulating tumor cells (CTCs) as novel biomarkers are widely investigated in various cancers, although most of the literature shows that CTCs have predictive value for recurrence, metastasis, and prognosis after CRC surgery, results remain controversial. We aimed to systematically evaluate the value of CTCs in monitoring of colorectal cancer (CRC) recurrence and metastasis after surgery.

Method

The PubMed, Cochrane Library, Embase, and other databases were searched from the establishment of the database to May 27, 2021. Relevant literature searches and data extraction were performed independently by two reviewers. The quality assessment was performed using the QUADAS2 scale developed by the Cochrane collaboration. The heterogeneity was checked using the Spearman correlation coefficient and the Cochran-Q test in the Meta-Disc1.4 software. Subgroup analysis was used to explore the source of heterogeneity. Considering that all the included papers were clinical studies with clinical heterogeneity, random effect model was adopted for analysis. And the sensitivity (Sen), specificity (Spe), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curves of CTCs, in monitoring recurrence and metastasis after CRC, were calculated. The publication bias of the included studies was assessed using Deek’s funnel figure.

Result

The literature included a total of 13 articles, comprising 1788 cases, and the overall quality of the literature was high. After summing up the indicators, the sensitivity pooled-value of the peripheral blood CTCs to monitor the recurrence and metastasis value of CRC after CRC was 0.67 [95%CI (0.62, 0.71)], specificity pooled-value was 0.71 [95%CI (0.67, 0.72)], PLR pooled-value was 2.37 [95%CI [1.52, 3.71]), NLR pooled into 0.53 [95%CI (0.36, 0.78)], DOR pooled into 4.97 [95%CI (2.11, 11.72)], AUC was 0.7395.

Conclusion

Peripheral blood CTCs have a moderate monitoring value for recurrence and metastasis after CRC; CTCs detected one week after surgery may be more correlated with recurrence and metastasis.

Tissue-Infiltrating Lymphocytes as a Predictive Factor for Recurrence in Patients with Curatively Resected Colon Cancer: A Propensity Score Matching Analysis

BACKGROUND

In patients with colorectal cancer, the rate of recurrence increases as the histologic stage progresses. However, the prediction of recurrence in individual patients is difficult. Many studies have reported on the relation between outcomes and tissue-infiltrating lymphocytes (TILs). The aim of our study was to clarify the relation between TILs and oncologic outcomes in patients with colon cancer using propensity score matching analysis.

METHODS

The study group comprised 513 patients with colon cancer who received curative resection. By using propensity score matching for sex, age, tumor location, T stage, N stage, histologic type, and adjuvant therapy as conventional prognostic factors, 61 patients with recurrence and 61 patients with no recurrence were selected. Hematoxylin-eosin staining and immunohistochemical staining using CD3, CD8, CD4, and FoxP3 were performed for lymphocytes in the primary tissue. The results were evaluated separately in the whole tumor, the central part, and the invasive margin.

RESULTS

The median follow-up period was 53 months. Among the 513 patients, 70 had recurrence and 443 had no recurrence. In the comparison of outcomes between the 61 patients with recurrence and the 61 patients with no recurrence, univariate analysis showed that the disease-free survival rate was significantly higher among the patients with positive TILs in the whole tumor and in the invasive margin (p = 0.016 and p = 0.012, respectively) and with CD8+ cells in the central part (p = 0.039) than among those with negative results. A multivariate analysis showed that TILs in the invasive margin (hazard ratio 1.81; 95% confidence interval, 1.03-3.05; p = 0.037) and CD8+ cell density in the central part (hazard ratio 1.76; 95% confidence interval, 1.07-2.93; p = 0.023) were prognostic factors that were independent from conventional prognostic factors.

CONCLUSIONS

In patients with curatively resected colon cancer, TILs in the invasive margin and CD8+ cell density in the central part may be prognostic factors suggesting host antitumor immune response.

Prognostic models based on postoperative circulating tumor cells can predict poor tumor recurrence-free survival in patients with stage II-III colorectal cancer

Background: It is urgent to develop robust prognostic biomarkers for non-metastatic colorectal cancer (CRC) patients undergoing surgery. The current study aimed to explore and compare the clinical significance of preoperative and postoperative blood tumor biomarkers including circulating tumor cells (CTCs), and develop prognostic models based on tumor biomarkers in patients with stage II-III CRC receiving surgery. Methods: A prospective study was performed to enroll 130 patients with stage II-III CRC receiving surgery between January 2015 and December 2017. Preoperative and postoperative blood tumor biomarkers including CTCs were detected and their prognostic value in predicting tumor recurrence-free survival (RFS) in stage II-III CRC were identified by Kaplan-Meier curves and Cox proportional hazard regression models. Results: CTCs counts within three postoperative days were significantly higher than preoperative CTCs (pre-CTCs). No significant association of pre-CTCs with clinical characteristics and tumor biomarkers was observed while positive postoperative CTCs (post-CTCs) were associated with female, older onset age, high TNM stage, tumor recurrence, and preoperative CEA. Kaplan-Meier curve with log-rank test and univariate Cox proportional hazard regression analysis suggested high N stage, TNM stage, positive pre-carbohydrate antigen (CA) 125, pre-CA19-9, post-CA125, post-CA19-9, post-CA72-4, post-carcinoembryonic antigen (CEA), and post-CTCs were correlated with poor RFS. In multivariate analysis, only TNM stage (adjusted HR=3.786, 95% CI=1.330-10.780; P=0.013), post-CA72-4 (adjusted HR=5.675, 95% CI=2.064-15.604; P=0.001), and post-CTCs (adjusted HR=2.739, 95% CI=1.042-7.200; P=0.041) were significantly correlated with poor RFS. We then developed prognostic models combining post-CTCs and post-CA72-4 with TNM stage or not to stratify the patients into different risk groups. These prognostic models exert a similar good performance in predicting tumor RFS in stage II-III CRC patients. Conclusions: Postoperative CTCs were prior to preoperative CTCs in predicting tumor recurrence survival in non-metastatic CRC patients undergoing surgery. We also developed CTCs-based prognostic models to predict tumor recurrence in stage II-III CRC, which might be used to identify the patients with high risk of recurrence and guide aggressive treatment to improve the clinical outcomes of those patients.

Meta-analysis Reveals the Prognostic Value of Circulating Tumour Cells Detected in the Peripheral Blood in Patients with Non-Metastatic Colorectal Cancer

Detecting circulating tumour cells (CTCs) is considered as effective and minimally invasive technique to predict the prognosis of patients with metastatic colorectal cancer (CRC), but its clinical validity is still conflicting in patients without metastasis. We performed this meta-analysis to evaluate whether detection of CTCs in the peripheral blood can be used as a prognostic marker for patients with non-metastatic CRC. We performed a comprehensive search of the EMBASE, PubMed, and Web of Science databases (up to September 2016). Meta-analyses were conducted using a random-effects model with the hazard ratio (HR) and 95% confidence interval (95% CI) as the effect measures. Twenty studies including 3,687 patients were eligible for inclusion. Overall analyses demonstrated that the presence of CTCs was significantly associated with aggressive disease progression (HR = 2.57, 95% CI = 1.64-4.02, P _{heterogeneity}  < 0.001, I ²  = 81.0%) and reduced disease survival (HR = 2.41, 95% CI = 1.66-3.51, P _{heterogeneity}  = 0.002, I ²  = 59.7%). Subgroup analyses further supported the prognostic effect of CTCs based on different subsets, including sampling time, detection method and cancer type. Our findings suggest that detection of CTCs in the peripheral blood has the clinical utility to indicate poor prognosis in patients with non-metastatic CRC.

Treatment Rationale and Study Design for Clinical Trial on the Efficacy of UFT/LV for Stage II Colorectal Cancer With Risk Factors for Recurrence (JFMC46-1201)

BACKGROUND

The usefulness of adjuvant chemotherapy for stage II colon cancer has not been established. Meanwhile, the presence of stage II colon cancer with high-risk factors for recurrence has been reported. To our knowledge, no prospective study of adjuvant chemotherapy for stage II colon cancer with high-risk factors has been implemented to date.

PATIENTS AND METHODS

This study is a prospective nonrandomized controlled study based on patients' selection of treatment option, including randomized therapeutic decision-making, to evaluate the usefulness of adjuvant chemotherapy with tegafur-uracil (UFT) with leucovorin (LV) for stage II colon cancer with high-risk factors for recurrence, compared with surgery alone. Five courses of UFT/LV therapy will be given as follows: UFT (300 mg/m(2)/d) with LV (75 mg/d) will be orally administered in 3 doses per day. Treatment will be received daily for 28 days, followed by a 7-day rest or will be received daily for 5 days, followed by a 2-day rest. For both regimens, 1 course will last 5 weeks, and 5 courses will be given. The primary end point is disease-free survival. A propensity score matching will be conducted based on 7 variables that represent risk factors to minimize selection bias in a comparison between the nonrandomized arms. For this nonrandomized comparison, a target sample size is set at 1200 (400 and 800 patients for the surgery alone and UFT/LV groups, respectively) and 1720 patients will be enrolled. In this study we aim to evaluate the therapeutic usefulness of adjuvant chemotherapy with UFT/LV for stage II colorectal cancer with risk factors for recurrence.

Circulating tumour cells and outcome in non-metastatic colorectal cancer: a prospective study

BACKGROUND

Circulating tumour cells (CTC) in the blood have been accepted as a prognostic marker in patients with metastatic colorectal cancer (CRC). Only limited data exist on the prognostic impact of CTC in patients with early stage CRC using standardised detection assays. The aim of this study was to elucidate the role of CTC in patients with non-metastatic CRC.

METHODS

A total of 287 patients with potentially curable CRC were enrolled, including 239 patients with UICC stage I-III. CTC were measured in the blood using the CellSearch system preoperatively and on postoperative days 3 and 7. The complete patient group (UICC I-IV) and the non-metastatic cohort (UICC I-III) were analysed independently. Patients were followed for 28 (0-53) months. Prognostic factors for overall and progression-free survival were analysed using univariate and multivariate analyses.

RESULTS

CTC were detected more frequently in patients with metastatic disease. No clinicopathological variables were associated with CTC detection in non-metastatic patients. CTC detection (⩾1 CTC per 7.5 ml blood) in the blood was significantly associated with worse overall survival (49.8 vs 38.4 months; P<0.001) in the non-metastatic group (UICC I-III), as well as in the complete cohort (48.4 vs 33.6 months; P<0.001). On multivariate analysis CTC were the strongest prognostic factor in non-metastatic patients (hazard ratio (HR) 5.5; 95% confidence interval (CI) 2.3-13.6) as well as in the entire study group (HR 5.6; 95% CI 2.6-12.0).

CONCLUSIONS

Preoperative CTC detection is a strong and independent prognostic marker in non-metastatic CRC.

Meta-analysis of the prognostic value of circulating tumor cells detected with the CellSearch System in colorectal cancer

BACKGROUND

The prognostic value of circulating tumor cells (CTCs) detected with the CellSearch System in patients with colorectal cancer (CRC) is controversial. The aim of our meta-analysis was to evaluate whether the detection of CTCs in the peripheral blood with the standardized CellSearch System has prognostic utility for patients with CRC.

METHODS

The PubMed, Science Citation Index, Cochrane Database, Embase, and the references in relevant studies were systematically searched (up to December, 2014). No search restrictions were imposed. Our meta-analysis was performed in Stata software, version 12.0 (2011) (Stata Corp, College Station, TX, USA), with the odds ratio (OR), risk ratio (RR), hazard ratio (HR), and 95% confidence interval (95% CI) as the effect measures. Subgroup and sensitivity analyses were also conducted.

RESULTS

Eleven studies containing 1847 patients with CRC were analyzed. There was a significantly higher incidence of CTCs in the metastasis-positive group than in the metastasis-negative group (OR = 4.06, 95% CI [1.74, 9.50], P < 0.01, I(2) = 0%). For hepatic metastasis, a type of metastasis, a higher incidence of CTCs was observed in the hepatic-metastasis-positive group than in the -negative group (OR = 2.61, 95% CI [1.73, 3.96], P < 0.01, I(2) = 0%). The presence of CTCs was significantly related to overall survival (HR = 2.00, 95% CI [1.49, 2.69], P < 0.01, I(2) = 67.1%) and progression-free survival (HR = 1.80, 95% CI [1.52, 2.13], P < 0.01, I(2) = 43.9%) of patients with CRC, regardless of the sampling time. The response rate for the CTC(+) groups was significantly lower than that for the CTC(-) groups at baseline and during treatment (baseline: 33% versus 39%, RR = 0.79, 95% CI [0.63, 0.99], P = 0.04, I(2) = 7.0%; during treatment: 17% versus 46%, RR = 0.41, 95% CI [0.22, 0.77], P = 0.01, I(2) = 0.0%;).

CONCLUSIONS

Our meta-analysis indicates that the detection of CTCs in the peripheral blood with the CellSearch System has prognostic utility for patients with CRC.

Clinical impact of minimal cancer cell detection in various colorectal cancer specimens

Detection of cancer cells using molecular targets is achieved by combining immunochemical reactions with gene amplification techniques. This enables the detection of cancer cells in specimens that are traditionally determined to be cancer-free. These improvements in detection can lead to prognoses that are different from those derived by conventional pathological staging. Survival is worse when cancer cells are detected in regional lymph nodes compared to when the nodes are cancer-free. Furthermore, the circulating tumor cell (CTC) count increases as the cancer progresses. Consequently, there is a correlation between CTC count and prognosis. However, large-scale prospective studies are required to confirm this. The development of more convenient and cost-effective analysis techniques will facilitate the practical application of these findings.

Molecular biomarkers for the detection of metastatic colorectal cancer cells

Approximately half of all patients with colorectal cancer develop local recurrence or distant metastasis during the course of their illness. Recently, the molecular detection of metastatic cancer cells in various types of clinical samples, such as lymph nodes, bone marrow, peripheral blood, and peritoneal lavage fluid, has been investigated as a potential prognostic marker. The prognostic value of molecular tumor cell detection was independent of the type of detection method used. As assays become more sensitive and quantitative, a more thorough assessment of the cancer status of patients will be based on molecular markers alone. At present, it is difficult to conclude that one specific molecular marker is superior to others. Comparative analyses are recommended to assess the prognostic impact of molecular analyses in the same patient and determine the biomarkers that provide the most accurate prognostic information.

Prognostic significance of isolated tumor cells in patients with colorectal cancer in recent 10-year studies

Circulating tumor cells (CTCs) that detach from the primary tumor and move into the circulation are detected in patients with metastatic cancer. The discovery of such cancer cells has been used as a predictor of recurrence and prognosis, although a consensus regarding such applications has not been reached. Peritoneal cytology may be used for identifying high risk of recurrence or mortality, whereas the intraoperative presence of tumor cells in drainage veins, bone marrow, or the liver is not always useful for evaluating the prognosis. The reported positive rate for tumor cells in the peripheral blood of patients with colorectal cancer, including metastasis, has varied from 10 to 80%; however, numerous studies have demonstrated significant differences in the recurrence and mortality rates between patients with and without isolated tumor cells (ITCs) in the peripheral blood. However, the clinical significance of CTCs as an absolute prognostic factor has not been elucidated, since the measurement methodologies and/or the number of cases differed between the studies. Future prospective studies including larger patient populations may elucidate the utility of routine detection of ITCs in daily practice.

Investigation of free cancer cells in peripheral blood using CEA mRNA expression in perioperative colorectal cancer patients

The aim of this study was to evaluate the impact of laparoscopic surgery (Lap) on circulating free tumor cells in colorectal cancer patients. In this study, we selected carcinoembryonic antigen (CEA) mRNA expression in peripheral blood as the marker of the circulating tumor cells and compared this marker between Lap and open colectomy (OC), to investigate differences due to surgical approach. A total of 50 patients underwent curative surgery for solitary colorectal cancer at our department, between June, 2008 and February, 2011. The patients were divided into OC and Lap groups (25 patients each). Total RNA was extracted subsequent to peripheral blood collection prior to surgery, immediately following surgery and 1, 3 and 7 days after surgery. CEA mRNA was detected with reverse transcription polymerase chain reaction (RT-PCR) and the association between peripheral blood CEA mRNA-positive rate, surgical findings and clinicopathological characteristics was investigated. The peripheral blood CEA mRNA-positive rate was significantly increased immediately after surgery, compared to the preoperative rate (P=0.001), but decreased over time. No significant differences were observed at any blood-sampling time point after postoperative day 1. The positive rate was significantly increased in the OC group immediately after surgery, compared to the preoperative rate (P=0.004). However, there were no significant differences between the rates prior to and immediately after surgery in the Lap group. The patients were then divided into those who were peripheral blood CEA mRNA-positive and -negative after surgery (postoperative positive and negative groups, respectively) and the clinicopathological characteristics were compared. Significant differences were identified between the groups in lower rectal cancer patients and patients with a large intraoperative blood loss (P=0.001 and P=0.01, respectively). In conclusion, in colorectal cancer patients, there were no significant differences in the perioperative peripheral blood CEA mRNA-positive rate or its short-term changes between patients undergoing OC and Lap surgery. It was suggested that Lap is equivalent to OC with regard to free cancer cells.

Evaluation of alpha 1-antitrypsin and the levels of mRNA expression of matrix metalloproteinase 7, urokinase type plasminogen activator receptor and COX-2 for the diagnosis of colorectal cancer

Background

Colorectal cancer (CRC) is the second most common cause of death from cancer in both men and women in the majority of developed countries. Molecular tests of blood could potentially provide this ideal screening tool.

Aim

Our objective was to assess the usefulness of serum markers and mRNA expression levels in the diagnosis of CRC.

Methods

In a prospective study, we measured mRNA expression levels of 13 markers (carbonic anhydrase, guanylyl cyclase C, plasminogen activator inhibitor, matrix metalloproteinase 7 (MMP7), urokinase-type plasminogen activator receptor (uPAR), urokinase-type plasminogen activator, survivin, tetranectin, vascular endothelial growth factor (VEGF), cytokeratin 20, thymidylate synthase, cyclooxygenase 2 (COX-2), and CD44) and three proteins in serum (alpha 1 antitrypsin, carcinoembryonic antigen (CEA) and activated C3 in 42 patients with CRC and 33 with normal colonoscopy results.

Results

Alpha 1-antitrypsin was the serum marker that was most useful for CRC diagnosis (1.79±0.25 in the CRC group vs 1.27±0.25 in the control group, P<0.0005). The area under the ROC curve for alpha 1-antitrypsin was 0.88 (0.79–0.96). The mRNA expression levels of five markers were statistically different between CRC cases and controls: those for which the ROC area was over 75% were MMP7 (0.81) and tetranectin (0.80), COX-2 (0.78), uPAR (0.78) and carbonic anhydrase (0.77). The markers which identified early stage CRC (Stages I and II) were alpha 1-antitrypsin, uPAR, COX-2 and MMP7.

Conclusions

Serum alpha 1-antitrypsin and the levels of mRNA expression of MMP7, COX-2 and uPAR have good diagnostic accuracy for CRC, even in the early stages.

Peri-operative bowel perforation in early stage colon cancer is associated with an adverse oncological outcome

BACKGROUND

The presence of an inflammatory response resulting from bowel perforation or anastomotic leakage has been suggested to enhance recurrence rates in colorectal cancer patients. Currently, it is unknown if bowel perforation or anastomotic leakage has prognostic significance in early stage colon cancer patients. In this study, the impact of peri-operative bowel perforation including anastomotic leakage on disease-free survival of stage I/II colon cancer patients was investigated.

METHODS

Prospective follow up data of 448 patients with stages I/II colon cancer that underwent resection were included. Patients who died within 3 months after initial surgery were excluded.

RESULTS

Median follow up was 56.0 months. Patients with peri-operative bowel perforation (n = 25) had a higher recurrence rate compared to patients without perforation (n = 423), 36.0 % vs. 16.1 % (p = 0.01). Disease-free survival was significantly worse for the perforation group compared to patients without perforation (p = 0.004). Multivariate analysis including T-stage, histological grade, and adjuvant chemotherapy showed peri-operative bowel perforation to be an independent factor significantly associated with disease recurrence (odds ratio, 2.7; 95 % CI, 1.1-6.7).

CONCLUSION

Peri-operative bowel perforation is associated with increased recurrence rates and impaired disease-free survival in early-stage colon cancer patients.

Clinical significance of and future perspectives for hepatic arterial infusion chemotherapy in patients with liver metastases from colorectal cancer

The most common site of metastases in patients with colorectal cancer is the liver. Hepatic resection is considered to be the treatment of choice for liver metastasis from colorectal cancer; however, hepatic resection can be performed in only 20 or 25% of all patients. Recurrence develops in the remnant liver or other organs after hepatic resection in over half of all patients with liver-only metastasis. Hepatic arterial infusion (HAI) chemotherapy can provide relatively high concentrations of drugs to microscopic or macroscopic metastases in the liver, with less toxicity than systemic administration. Meta-analyses have shown HAI chemotherapy to have a significantly higher response rate than systemic chemotherapy and its effect on extrahepatic metastases is negligible. HAI chemotherapy provides much better local control of liver metastases from colorectal cancer than systemic chemotherapy. However, well-controlled studies are needed to elucidate the optimal treatment strategies for neoadjuvant and postoperative adjuvant chemotherapy that optimally combine HAI chemotherapy, molecular targeted agents, and systemic chemotherapy such as FOLFOX or FOLFIRI.

Influence of surgical manipulation and surgical modality on the molecular detection of circulating tumor cells from colorectal cancer

Purpose

The aim of this study was to evaluate the relationship between the detection of circulating tumor cell molecular markers from localized colorectal cancer and the time-course of a surgical manipulation or surgical modality.

Methods

From January 2010 to June 2010, samples from the peripheral blood and the inferior mesenteric vein were collected from 42 patients with cancer of the sigmoid colon or rectum. Pre-operative, intra-operative (both pre-mobilization and post-mobilization), and post-operative samples were collected. We examined carcinoembryonic antigen (CEA) mRNA and cytokeratin-20 (CK20) mRNA by real-time reverse-transcriptase polymerase chain reaction. Changes in mRNA detection rates were analyzed according to the time of blood sample collection, the surgical modality, and patient clinicopathological features.

Results

mRNA expression rates before surgical resection did not differ between blood samples from the peripheral and inferior mesenteric veins. The detection rate for CEA and CK20 mRNA showed a tendency to increase after operative mobilization of the cancer-bearing bowel segment. Furthermore, the cumulative detection rates for CEA and CK20 mRNA increased significantly over the course of surgery (pre-mobilization vs. post-mobilization). The cumulative detection rate decreased significantly after surgical resection compared with the pre-operative rates. However, no significant difference was observed in the detection rates between different surgical modalities (laparoscopy vs. open surgery).

Conclusion

The results of this study suggest that surgical manipulation has a negative influence on the dissemination of circulating tumor cells during operations on localized colorectal cancer. However, the type of surgical technique did not affect circulating tumor cells.

Prognostic role of carcinoembryonic antigen is influenced by microsatellite instability genotype and stage in locally advanced colorectal cancers

BACKGROUND

Carcinoembryonic antigen (CEA) is the most frequently used marker for colorectal cancer (CRC). Influence of genetic instability on tumor marker expression is not known. The aim of this study was to investigate microsatellite instability (MSI) of CEA serum levels in locally advanced CRC.

METHODS

The observational cohort consisted of stage II-III CRC patients (n = 131) 75 years old or youngerwho underwent surgery with curative intent. CEA serum levels were measured before (preCEA) and immediately after surgery (postCEA). DNA from the extracted tumors was investigated for MSI. Survival was analyzed in univariate and multivariate analyses.

RESULTS

The median preCEA was 3 U/ml (IQR = 1-3, range = 1-136 U/ml). Stage III cancers with MSI had an elevated preCEA more often than those without MSI (25% vs. 0%; p = 0.026). A preCEA >10 U/ml was significantly associated with elevated postCEA (CEA >1 U/ml; odds ratio [OR] = 5.4, 95% CI = 2.1-14.2; p < 0.001). Survival wasnot significantly different between those with postCEA <10 U/ml vs. postCEA ≥ 10 U/ml or when stratified by MSI status. A cutoff of postCEA ≤ 1 U/ml conferred significantly improved survival compared to higher CEA levels. Stratified for MSI status, this difference was significant for microsatellite stable (MSS) cancers only (p = 0.021). In multivariate analysis, postCEA >1 U/ml (hazard ratio [HR] = 3.5, 95% CI = 1.7-7.3, p = 0.001) and stage III (HR = 6.7, 95% CI = 3.0-14.9; p < 0.001) were predictors of decreased survival.

CONCLUSIONS

Preoperative CEA levels were significantly higher in stage III cancers with the MSI genotype, and high preoperative CEA was associated with increased postoperative CEA. Absent postoperative CEA in serum conferred improved long-term survival.

The clinical significance of circulating tumor cells in non-metastatic colorectal cancer--a review

BACKGROUND

Finding a clinical tool to improve the risk stratification and identifying those colorectal cancer patients with an increased risk of recurrence is of great importance. The presence of circulating tumor cells (CTC) in peripheral blood can be a strong marker of poor prognosis in patients with metastatic disease, but the prognostic role of CTC in non-metastatic colorectal cancer is less clear. The aim of this review is to examine the possible clinical significance of circulating tumor cells in non-metastatic colorectal cancer (TNM-stage I-III) with the primary focus on detection methods and prognosis.

METHODS

The PubMed and Cochrane database and reference lists of relevant articles were searched for scientific literature published in English from January 2000 to June 2010. We included studies with non-metastatic colorectal cancer (TNM-stage I-III) and CTC detected pre- and/or post-operatively in peripheral blood.

RESULTS

Nine studies qualified for further analyses. Detection rates of CTC in peripheral blood of patients with non-metastatic colorectal cancer varied from 4% to 57%. Seven studies applied RT-PCR and two studies used immunocytochemical methods. Seven studies found the presence of CTC to be a prognostic marker of poor disease-free survival.

CONCLUSION

The presence of CTC in peripheral blood is a potential marker of poor disease-free survival in patients with non-metastatic colorectal cancer. The low abundance of CTC in non-metastatic colorectal cancer requires very sensitive and specific detection methods. An international consensus on choice of detection method and markers, is warranted before incorporating CTC into risk stratification in the clinical setting.

Predictive markers of colorectal cancer liver metastases

Liver metastases are the most common site of distant failure after curative resection of colorectal cancer and a source of significant cancer-related morbidity and mortality. Currently, imaging and conventional histopathologic features, such as T-stage and N-stage, are used by clinicians to inform prognosis and guide adjuvant treatment to reduce the risk of developing distant metastases. However, these tools only have a moderate ability to predict the development of liver metastases. Novel methods, including the detection of circulating tumor cells and carcinoembryonic antigens in serum, have been developed, and their prognostic and predictive characteristics have been assessed. In addition, several molecular and genetic markers in the primary tumor have been studied. Unfortunately, these studies are often small and their results have been mixed, yielding no consistent sets of externally validated predictors of colorectal liver metastases. For widespread clinical relevance, future tests need to be independently carried out on large independent patient samples.

Multiplex RT-PCR-based detections of CEA, CK20 and EGFR in colorectal cancer patients

AIM: To develop a multiplex reverse transcription polymerase chain reaction (RT-PCR) method detecting circulating tumor cells in the peripheral blood of colorectal cancer (CRC) patients.

METHODS: Peripheral blood samples were collected from 88 CRC patients and 40 healthy individuals from the blood donors’ clinic and subsequently analyzed by multiplex RT-RCR for the expression of carcinoembryonic antigen (CEA), cytokeratin 20 (CK20) and epidermal growth factor receptor (EGFR) mRNA. The analysis involved determining the detection rates of CEA, CK20 and EGFR transcripts vs disease stage and overall survival. Median follow-up period was 19 mo (range 8-28 mo).

RESULTS: Rates of CEA, CK20 and EGFR detection in CRC patients were 95.5%, 78.4% and 19.3%, respectively. CEA transcripts were detected in 3 healthy volunteer samples (7.5%), whereas all control samples were tested negative for CK20 and EGFR transcripts. The increasing number of positive detections for CEA, CK20 and EGFR transcripts in each blood sample was positively correlated with Astler-Coller disease stage (P < 0.001) and preoperative serum levels of CEA (P = 0.029) in CRC patients. Data analysis using Kaplan-Meier estimator documented significant differences in the overall survival of the different CRC patient groups as formed according to the increasing number of positivity for CEA, CK20 and EGFR transcripts.

CONCLUSION: These data suggest that multiplex RT-PCR assay can provide useful information concerning disease stage and overall survival of CRC patients.

Serum sE-selectin levels and carcinoembryonic antigen mRNA-expressing cells in peripheral blood as prognostic factors in colorectal cancer patients

BACKGROUND

This study analyzed the possible prognostic value of presurgical serum soluble (s)E-selectin levels and/or carcinoembryonic antigen (CEA) mRNA positivity in predicting the disease-free survival of colorectal cancer (CRC) patients.

METHODS

CEA mRNA (obtained from blood-borne cells by reverse transcriptase-polymerase chain reaction [RT-PCR]), tumor necrosis factor-alpha (TNF-alpha), and sE-selectin levels were analyzed in blood samples obtained from 78 patients with primary (n = 62) or recurrent (n = 16) CRC, 40 patients with benign colorectal (CR) diseases, and 78 controls.

RESULTS

CEA mRNA positivity by RT-PCR was significantly associated with advanced stage (P < .05). Median baseline sE-selectin levels were higher in patients with CRC (43 ng/mL) compared with controls (36 ng/mL) or patients with benign CR diseases (31 ng/mL, P < .001). These were significantly associated with CEA mRNA positivity by RT-PCR (P < .05). Multivariate analysis by forward stepping showed that elevated TNF-alpha (P = .001) and CEA mRNA positivity by RT-PCR (P = .0001) were independent predictors of elevated baseline sE-selectin levels. Positive presurgical sE-selectin levels were associated with an increased recurrence rate compared with patients with low levels of this molecule (P < .001). Positivity for both CEA mRNA and sE-selectin had a negative prognostic impact, with a 5-year recurrence-free survival rate of 51% compared with 95% of patients with negative parameters (P < .05).

CONCLUSIONS

Detection of presurgical serum sE-selectin levels and CEA mRNA-positive blood-borne cells in CRC patients might provide useful prognostic information in terms of recurrence-free survival, either alone or in combination, and may help in the choice of more aggressive treatment and/or more strict follow-up procedures in high-risk patients.

Lead time of carcinoembryonic antigen elevation in the postoperative follow-up of colorectal cancer did not affect the survival rate after recurrence

BACKGROUND AND AIMS

The role of carcinoembryonic antigen (CEA) in the early detection of recurrence during the postoperative follow-up of colorectal cancer remains unclear. We hypothesize that the tumor with longer lead time of CEA elevation to the definite recurrence may have a better prognosis because of its slower growth rate and closer observation.

MATERIALS AND METHODS

From 1995 to 2003, 4,841 consecutive patients who received curative resection of localized colorectal adenocarcinoma were enrolled from a prospective database. The patients with persisting CEA elevation after operation had been already excluded. Postoperative follow-up, including physical examination, imaging, and CEA test, were performed according to a surveillance program. A CEA >/=5 ng/mL was defined as elevated. The definition of the CEA lead time was the period between CEA elevation and detection of recurrence. All statistical analyses were performed by SPSS package for Windows (Microsoft, Redmond, WA, USA).

RESULTS

The postoperative median follow-up time for the 4,841 patients was 68 months. A total of 999 patients (20.6%) had CEA elevation and recurrence. Among these patients, recurrence was confirmed in 727 patients (72.8%)before, at the same time, or within 3 months of CEA elevation and thus had a short lead time of CEA elevation (SLT group). In 272 patients (27.2%), recurrence was confirmed after more than 3 months of CEA elevation and thus had a longer lead time of CEA elevation (LLT group). The recurrence pattern showed similarities in these two groups. A total of 193 patients (193/999, 19.3%) received a second radical operation, and 806 patients (80.7%) were inoperable. The re-resection rate between the SLT group (146 patients, 20.1%) and the LLT group (47 patients, 17.3%) was not significantly different. The overall survival rate after recurrence showed no difference between these two groups (P = 0.123).

CONCLUSION

Most cases of recurrence were detected at nearly the same time when the CEA level was elevated. Therefore, a more sensitive test is needed for early detection. The relationship between the lead time of CEA and the clinical outcome was not statistically significant. A more aggressive approach to the patient who has CEA elevation and is highly suspect of recurrence may be needed.

Meta-analysis shows that detection of circulating tumor cells indicates poor prognosis in patients with colorectal cancer

BACKGROUND & AIMS

The prognostic significance of circulating (CTCs) and disseminated tumor cells in patients with colorectal cancer (CRC) is controversial. We performed a meta-analysis of available studies to assess whether the detection of tumor cells in the blood and bone marrow (BM) of patients diagnosed with primary CRC can be used as a prognostic factor.

METHODS

We searched the Medline, Biosis, Science Citation Index, and Embase databases and reference lists of relevant articles (including review articles) for studies that assessed the prognostic relevance of tumor cell detection in the peripheral blood (PB), mesenteric/portal blood (MPB), or BM of patients with CRC. Meta-analyses were performed using a random effects model, with hazard ratio (HR) and 95% confidence intervals (95% CIs) as effect measures.

RESULTS

A total of 36 studies, including 3094 patients, were eligible for final analyses. Pooled analyses that combined all sampling sites (PB, MPB, and BM) associated the detection of tumor cells with poor recurrence-free survival (RFS) (HR = 3.24 [95% CI: 2.06-5.10], n = 26, I(2) = 77%) and overall survival (OS) (2.28 [1.55-3.38], n = 21, I(2) = 66%). Stratification by sampling site showed that detection of tumor cells in the PB compartment was a statistically significant prognostic factor (RFS: 3.06 [1.74-5.38], n = 19, I(2) = 78%; OS: 2.70 [1.74-4.20], n = 16, I(2) = 59%) but not in the MPB (RFS: 4.12 [1.01-16.83], n = 8, I(2) = 75%; OS: 4.80 [0.81-28.32], n = 5, I(2) = 82%) or in the BM (RFS: 2.17 [0.94-5.03], n = 4, I(2) = 78%; OS: 1.50 [0.52-4.32], n = 3, I(2) = 84%).

CONCLUSION

Detection of CTCs in the PB indicates poor prognosis in patients with primary CRC.

Prognostic significance of circulating tumour cells following surgical resection of colorectal cancers: a systematic review

Background:

The role of adjuvant chemotherapy after resection of colorectal cancers (CRCs) is well understood for patients with stage-I or stage-III disease. Its efficacy for those with stage-II disease remains much less clear. Many investigators have sought to identify prognostic markers that might clarify which patients have the highest risk of recurrence and would, therefore, be most likely to benefit from chemotherapy. This systematic review examines evidence for the use of peripherally sampled, circulating tumour cells (CTCs) as such a prognostic marker.

Methods:

A comprehensive literature search was used to identify studies reporting on the significance of CTCs in the postoperative blood of CRC patients.

Results:

Fourteen studies satisfied the inclusion criteria. Six of the nine studies that took blood samples 24 h or more postoperatively found detection of postoperative CTCs to be an independent predictor of cancer recurrence.

Conclusion:

The presence of CTCs in peripheral blood at least 24 h after resection of CRCs is an independent prognostic marker of recurrence. Further studies are needed to clarify the optimal time point for blood sampling and determine the benefit of chemotherapy in CTC-positive patients with stage-II disease.

Detection of epithelial cells by RT-PCR targeting CEA, CK20, and TEM-8 in colorectal carcinoma patients using OncoQuick density gradient centrifugation system

BACKGROUND

The detection of epithelial-specific mRNA correlates well with the presence of cancer cells in the peripheral blood and provides a rational explanation for subsequent metastasis.

MATERIAL AND METHODS

Forty-two, patients with colorectal cancer and 14 controls were included in our study. Peripheral blood samples were acquired at 24 h before and 48 h after laparotomy. Tissue samples were also acquired from the primary lesion. All samples were examined for the expression profile of CEA, CK20, and TEM-8.

RESULTS

Tissue samples expressed CEA in every specimen, CK20 in 30, and TEM-8 in 41. CEA and CK20 were not identified in the control blood samples while TEM-8 was detected in 4. CEA was detected in 17, CK20 in 28 and TEM-8 in 23, of the preoperative blood samples. CEA mRNA expression in preoperative blood sample and TNM stage were found independently associated with increased tumor size. Positive CEA, CK20, and TEM-8 signals were found in 25, 25, and 23 of the postoperative blood samples respectively.

CONCLUSIONS

CK20 and CEA are significantly more frequently detected in colon cancer patients than in healthy controls and can serve as markers. Cancer cell mRNA is commonly detected in the preoperative and postoperative peripheral blood samples. Tumor size was independently associated with the preoperative detection of CEA mRNA. Although TEM-8 mRNA detection in the peripheral blood showed no specificity for cancer patients or correlation with clinical stage, identification and validation of genes and proteins implicated in metastatic process needs to be further investigated.

The role of carcinoembriogenic antigen in predicting response and survival to neoadjuvant chemoradiotherapy for distal rectal cancer

PURPOSE

Carcinoembriogenic antigen (CEA) is the most frequently used tumor marker in rectal cancer. A decrease in carcinoembriogenic antigen after radical surgery is associated with survival in these patients. Neoadjuvant chemoradiotherapy may lead to significant primary tumor downstaging, including complete tumor regression in selected patients. Therefore, we hypothesized that a decrease in CEA after neoadjuvant chemoradiotherapy could reflect tumor response to chemoradiotherapy, affecting final disease stage and ultimately survival.

METHODS

Patients with distal rectal cancer managed by neoadjuvant chemoradiotherapy and available pretreatment and postchemoradiotherapy levels of CEA were eligible for the study. Outcomes studied included final disease stage, relapse, and survival, and these were compared according to initial CEA level, post-chemoradiotherapy CEA level, and the reduction in CEA.

RESULTS

Overall 170 patients were included. Post-chemoradiotherapy CEA levels <5 ng/ml were associated with increased rates of complete clinical response and pathologic response. Additionally, postchemoradiotherapy CEA levels <5 ng/ml were associated with increased overall and disease-free survival (P = 0.01 and P = 0.03). There was no correlation between initial CEA level or reduction in CEA and complete response or survival.

CONCLUSION

A postchemoradiotherapy CEA level <5 ng/ml is a favorable prognostic factor for rectal cancer and is associated with increased rates of earlier disease staging and complete tumor regression. Postchemoradiotherapy CEA levels may be useful in decision making for patients who may be candidates for alterative treatment strategies.

Preoperative serum carcinoembryonic antigen level as a predictive factor of recurrence after curative resection of colorectal cancer

BACKGROUND

We evaluated the prognostic value of the preoperative serum carcinoembryonic antigen (CEA) level in patients with colorectal cancer (CRC).

PATIENTS AND METHODS

The study group comprised 638 patients. The optimal cutoff value for the preoperative serum CEA level was determined. Predictive factors of recurrence were evaluated using multivariate analyses. The relapse-free time was investigated according to the CEA level.

RESULTS

All patients underwent potentially curative resection for CRC without distant metastasis, classified as stage I, II, or III. The optimal cutoff value for preoperative serum CEA level was 10 ng/ml. Elevated preoperative serum CEA level was observed in 92 patients. Multivariate analysis identified tumor-node-metastasis (TNM) stage and preoperative serum CEA level as independent predictive factors of recurrence. The relapse-free survival between CEA levels >10 ng/ml and <10 ng/ml significantly differed in patients with stage II and III. However, there was no significant difference in relapse-free survival between CEA levels >10 ng/ml and <10 ng/ml in patients with stage I.

CONCLUSION

Preoperative serum CEA is a reliable predictive factor of recurrence after curative surgery in CRC patients and a useful indicator of the optimal treatment after resection, particularly for cases classified as stage II or stage III.

Progress in the development of prognostic and predictive markers for gastrointestinal malignancies

Gastrointestinal cancers remain a significant cause of morbidity and mortality. While increasing therapeutic options have improved outcomes for many patients, they have also complicated treatment decision-making. Unfortunately, most patients with advanced gastrointestinal malignancies die from their disease. Prognostic and predictive markers could improve treatment significantly by identifying patients who may or may not require a given therapy, and determining those most likely to benefit from a therapy. Candidates for such markers include blood antigens and circulating tumor cells, tumor enzyme and gene expression, and pharmacodynamic endpoints. In this review, we summarize reported and ongoing research to define and validate prognostic and predictive markers in gastrointestinal malignancies, with an emphasis on colorectal cancer and brief overview of pancreatic and neuroendocrine tumors.

Persistent presence of postoperative circulating tumor cells is a poor prognostic factor for patients with stage I-III colorectal cancer after curative resection

AIM

To detect pre- and postoperative circulating tumor cells (CTCs) in stage I-III colorectal cancer (CRC) patients undergoing curative resection and so identify a subgroup of patients who are at high risk for relapse.

METHODS

Four mRNA molecular markers including human telomerase reverse transcriptase, cytokeratin-19, cytokeratin-20, and carcinoembryonic antigen mRNA were used to detect CTCs in 438 CRC patients underwent curative resection.

RESULTS

Out of 438 patients, 80 CRC patients were classified to preoperative (-)/postoperative (-), 221 patients were preoperative (+)/postoperative (-), while 137 patients were preoperative (+)/postoperative (+). Univariately, postoperative relapse was significantly correlated with depth of invasion (P = 0.032), lymph node metastasis (P < 0.001), vascular invasion (P = 0.001), perineural invasion (P = 0.013), and persistent presence of CTCs (P < 0.001). Using a multivariate proportional hazards regression analysis, the presence of lymph node metastasis (P = 0.012; HR, 7.652; 95% CI: 4.162-14.827), vascular invasion (P = 0.033; HR, 4.360; 95% CI: 2.793-10.847), and the persistent presence of CTCs (P < 0.001; HR, 29.486; 95% CI: 10.281-87.792) were demonstrated to be independent predictors for postoperative relapse. Combination of these three independent predictors showed that patients with any one positive predictor had a hazard ratio of sevenfold to develop postoperative relapse (P < 0.001; HR, 7.064; 95% CI: 4.354-11.464). Furthermore, the persistent presence of CTCs was strongly correlated with poorer relapse-free survival rates (all P < 0.001).

CONCLUSION

The promising results of this study suggest that persistent presence of postoperative CTCs may be a crucial prognostic factor adjuvant to conventional tumor markers in CRC patients who have undergone curative resection. Identification of these high-risk patients of persistent CTCs positivity is important and thus could help to define patients for adjuvant therapy with this tumor entity.

The mesenteric and antimesenteric site of the tumor as possible prognostic factor in colorectal cancer: 5-year survival analysis

INTRODUCTION

Colorectal cancer is still one of the many factors of death both in males and in females. To date, the most important prognostic factors are mainly related to the pathological stage of the disease.

AIM OF THE STUDY

The purpose of this study was to analyze the possible role of tumor circumferential localization on the colonic wall (mesenteric (M) or antimesenteric (AM)) as a possible prognostic factor. In this study, we compare the localization of the tumor with patient's survival. The hypothesis of this study is that M tumors, closer to blood and lymphatic vessels, should be more aggressive in terms of hematogenous and lymphatic spread compared to the AM tumors.

PATIENTS AND METHODS

All patients undergoing curative resection for colorectal cancer were enrolled in this study; there was no statistical difference for age, sex and co-morbidity. The histopathological examination was carried out in the standard manner. Next, we have taken care to survival of neoplastic patients by examining of our 5-year follow-up archive: we divided patients in different groups concerning the different tumor stage and we compare these results with the different localizations of tumor at the operation.

RESULTS

In 45% of cases, we were able to distinguish the different localizations M (160 patients) or AM (47 patients) and this difference is statistically significant (P<0.0001, Pearson Chi-Square-test (PCS-t)). The number of metastatic nodes is statistically higher in the M group compared to the AM group one (P=0.003949). Medium time of follow-up was 36.54 months; AM and M patients have a rather similar survival, only at the end the two curves seem to change but not in a significant manner. Only if we consider the difference between the two groups comparing T3 tumor can we observe a statistically significant difference (P<0.005).

CONCLUSIONS

In conclusion, the localization of M or AM colorectal cancer is feasible in 45% of cases. M tumors have significantly more lymph nodes metastases but a better 5-year survival than AM tumors. A possible explanation for such results might be the different pattern of diffusion of cancer cells.