C-stage in colon cancer: implications of carcinoembryonic antigen biomarker in staging, prognosis, and management

Increased serum carcinoembryonic antigen level can predict poor survival of patients with small cell lung cancer

Increased serum tumor biomarkers are usually associated with huge tumor burden, but the prognostic value of these markers remains controversial. The serum levels of carcinoembryonic antigen (CEA), nerve cell-specific enolase, and lactate dehydrogenase in 281 patients with small cell lung cancer (SCLC) were analyzed in this study. Increased serum CEA levels were observed in 92 (32.7%) patients. Survival was superior in patients with normal serum CEA levels compared with those with increased serum CEA levels. The median survival time, 2-year overall survival (OS) rate, and 3-year OS rate were 19.1 months vs 14.6 months, 42.7% vs 28.3%, and 30.6% vs 14.1%, respectively (P = 0.002). In multivariate analysis, extensive-stage (ES)-SCLC (hazard ratio [HR] = 1.936, P = 0.001), an increased serum CEA level (HR = 1.432, P = 0.021) at diagnosis, and <4 cycles of chemotherapy (ChT) (HR = 0.432, P = 0.001) were independent negative prognostic factors for the OS. Additionally, normal CEA level (HR = 1.678, P = 0.012), treatment modalities including surgery (HR = 1.595, P = 0.049), and ≥ 4 cycles of ChT (HR = 1.880, P = 0.004) were independent positive prognostic factors for OS in patients with local disease. In the subgroup with ES-SCLC, normal serum CEA level (HR = 1.608, P = 0.043), thoracic radiation therapy (HR = 1.744, P = 0.005), and ≥ 4 cycles of ChT (HR = 2.626, P = 0.001) were independent positive prognostic factors for OS.

Overall Survival of Stage III Colon Cancer with Only One Lymph Node Metastasis Is Independently Predicted by Preoperative Carcinoembryonic Antigen Level and Lymph Node Sampling Status

Background

This study identified predictors of favorable overall survival (OS) for stage III colon cancer patients who had only one lymph node (LN) metastasis (N1a).

Methods

Variables, including preoperative carcinoembryonic antigen (CEA) level, LN sampling status, and the choices of postoperative adjuvant chemotherapy, were recorded. Prognostic significance was determined using the log-rank test and multivariate Cox regression analysis.

Results

The median 42-month follow-up period included 363 eligible patients. Among them, 230 (63.3%) received only 5-flurouracil (5-FU) adjuvant chemotherapy; 76 (20.9%) underwent oxaliplatin-based regimens; and 57 (15.7%) chose surgery alone. The 5-year survival rate of these evaluated patients was 75%, 63%, and 77%, respectively (P = 0.823). Multivariate analysis revealed that normal preoperative CEA level (≦5 ng/mL) and adequate LN sampling (LN ≧ 12) were significant predictors for higher 5-year OS (P < 0.001; P = 0.007, respectively). However, the use of postoperative adjuvant chemotherapy in these N1a colon cancer patients did not significantly affect their 5-year OS.

Conclusions

A preoperative CEA level of less than or equal to 5 ng/mL, and curative surgery with an adequate lymphadenectomy determined a favorable OS outcome in stage III colon cancer with only one LN metastasis.

Carbohydrate antigen 19-9 is a useful prognostic marker in esophagogastric junction adenocarcinoma

The incidence rate of esophagogastric junction (EGJ) adenocarcinoma has been rapidly increasing worldwide. Carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) are major serum tumor markers in gastrointestinal cancers. However, the role of these markers in EGJ adenocarcinoma has not been thoroughly investigated. A total of 211 patients with EGJ adenocarcinoma who underwent surgery or endoscopic submucosal dissection at two academic institutions, Kumamoto University Hospital or Kyushu University Hospital between January 1996 and March 2014, were eligible for this study. Serum CEA and CA19-9 were examined within 1 month before resection. The cut-off values for CEA and CA19-9 were set at 5.0 ng/mL and 37 U/mL, respectively. The clinicopathological features and prognostic roles of the markers were examined using univariate and multivariate analyses. The positive ratios for preoperative CEA (>5.0 ng/mL) and CA19-9 (>37 U/mL) were 20.3% and 12.9%, respectively. The positive ratio of CEA and CA19-9 was significantly higher in patients with tumors invading muscular or deeper layers (P = 0.002 and <0.001, respectively). Cox proportional hazards model revealed that CA19-9 positivity, but not CEA positivity, was an independent prognostic factor in patients with EGJ adenocarcinoma for cancer-specific survival (multivariate hazard ratio [HR] = 3.89, 95% confidence interval [CI] 1.41-10.33; P = 0.010) and overall survival (multivariate HR = 2.43, 95% CI 1.03-5.35; P = 0.043). Preoperative serum CA19-9 is a useful prognostic marker in patients with EGJ adenocarcinoma.

Prognostic Effect of Pretreatment Serum Carcinoembryonic Antigen Level: A Useful Tool for Prediction of Distant Metastasis in Locally Advanced Rectal Cancer Following Neoadjuvant Chemoradiotherapy and Total Mesorectal Excision

Many studies have reported the prognostic value of pretreatment serum carcinoembryonic antigen (pre-CEA) levels on colorectal cancer outcomes. However, controversy remains concerning the significance of pre-CEA levels in patients with rectal cancer treated with neoadjuvant chemoradiotherapy (CRT). Our aim in this study was to investigate the prognostic role of the pre-CEA level in patients with locally advanced rectal cancer undergoing neoadjuvant CRT followed by total mesorectal excision (TME).A total of 419 patients with stages II and III rectal cancer treated with neoadjuvant CRT followed by TME with available pre-CEA data were included. The outcomes studied were 5-year local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS). Optimal pre-CEA cutoff values to predict DMFS were determined based on current smoking history.The median pre-CEA level of smokers was 3.8 ng/mL, and that of nonsmokers was 2.8 ng/mL (P < 0.01). Pre-CEA levels of 6.6 ng/mL for nonsmokers and 11.4 ng/mL for smokers were determined to best separate patients on the basis of time to distant metastasis by using log-rank statistics. The pre-CEA level was associated with DMFS (hazard ratio = 1.743, 95% confidence interval = 1.129-2.690, P = 0.01). The pre-CEA level was not associated with LRFS or DFS.The pre-CEA level appears to be a significant preoperative prognostic factor. Moreover, it is as valuable as any known pathologic factor. Future studies evaluating oncologic outcomes should take into consideration the pre-CEA level.

Trends and predictors of resection of the primary tumor for patients with stage IV colorectal cancer

BACKGROUND AND OBJECTIVES

Over 130,000 patients are diagnosed with colorectal cancer annually, with approximately 20% presenting with unresectable metastatic disease. Recent consensus guidelines recommend against primary tumor resection for asymptomatic patients with unresectable metastases. Our goal was to examine the trends and predictors of surgical resection.

METHODS

Cases of colorectal cancer with synchronous metastases diagnosed between 1988-2010 were identified using the Surveillance, Epidemiology and End Results (SEER) Database. Associations between resection and clinicopathologic variables were sought using univariate and multivariate logistic regression.

RESULTS

Overall, 68% of patients with synchronous metastatic colorectal cancer underwent primary tumor resection. Resection rates were as high as 76% in the earliest time period (1988-1992) and steadily dropped to 60% in the most recent period (2008-2010). Socioeconomic factors associated with resection on univariate analysis included age, race, gender, marital status, insurance status, and geographic region. Clinicopathologic characteristics associated with resection included tumor location, grade, size, and CEA level. In the multivariate model, gender, geographic region, insurance status, tumor location, grade and CEA level were independent predictors of primary tumor resection.

CONCLUSIONS

Surgical resection of the primary site remains common practice for patients with synchronous metastatic colorectal cancer. Treatment disparities are associated with socioeconomic as well as clinicopathologic factors.

Potential Prognostic Impact of Baseline CEA Level and Surgery of Primary Tumor Among Patients with Synchronous Stage IV Colorectal Cancer: A Large Population Based Study

Prognostic role of surgical resection of the primary tumor and baseline CEA among patients with synchronous stage IV colorectal cancer (CRC) remains an area of debate. The objective of this study was to determine the prognostic value of baseline CEA and surgical resection of the primary among patients with synchronous stage IV CRC in the era of modern chemotherapy and biologic therapy. The Surveillance, Epidemiology and End Results Registry was searched to identify patients with synchronous stage IV CRC diagnosed between 2004 and 2009. Colorectal-cancer-specific survival (CCS) was estimated using the Kaplan-Meier product limit method. Cox models were fitted to assess the multivariable relationship of various patient and tumor characteristics and CCS. Three hundred thirty-three thousand, three hundred ninety nine patients were identified in the SEER registry. Median CCS among patients with their primary tumor removed was 21 M vs. 7 M (primary intact) respectively (p < 0.001). Median CCS among patients who had an elevated vs. non-elevated baseline CEA level was 14 M vs. 24 M respectively (p < 0.0001). By multivariable analysis, patients with an elevated baseline CEA had a 56 % increased risk of death from CRC compared to those with a non-elevated CEA level (HR = 1.56, 95%CI 1.47-1.65, p < 0.0001). Similarly patients who underwent surgical resection of the primary tumor had a 33 % decreased risk of death from CRC compared to those who did not (HR = 0.61, 95%CI 0.54-0.69, p < 0.0001). In our review of this large population SEER based study, an elevated baseline CEA level and surgical resection of the primary tumor among patients with synchronous stage IV CRC appeared to impact survival outcomes. Prospective validation of these results in a surgically unresectable patient population will be required.

Dipeptidyl-peptidase IV activity is correlated with colorectal cancer prognosis

Background

Dipeptidyl-peptidase IV (EC 3.4.14.5) (DPPIV) is a serine peptidase involved in cell differentiation, adhesion, immune modulation and apoptosis, functions that control neoplastic transformation. Previous studies have demonstrated altered expression and activity of tissue and circulating DPPIV in several cancers and proposed its potential usefulness for early diagnosis in colorectal cancer (CRC).

Methods and principal findings

The activity and mRNA and protein expression of DPPIV was prospectively analyzed in adenocarcinomas, adenomas, uninvolved colorectal mucosa and plasma from 116 CRC patients by fluorimetric, quantitative RT-PCR and immunohistochemical methods. Results were correlated with the most important classic pathological data related to aggressiveness and with 5-year survival rates. Results showed that: 1) mRNA levels and activity of DPPIV increased in colorectal neoplasms (Kruskal-Wallis test, p<0.01); 2) Both adenomas and CRCs displayed positive cytoplasmic immunostaining with luminal membrane reinforcement; 3) Plasmatic DPPIV activity was lower in CRC patients than in healthy subjects (Mann-U test, p<0.01); 4) Plasmatic DPPIV activity was associated with worse overall and disease-free survivals (log-rank p<0.01, Cox analysis p<0.01).

Conclusion/significance

1) Up-regulation of DPPIV in colorectal tumors suggests a role for this enzyme in the neoplastic transformation of colorectal tissues. This finding opens the possibility for new therapeutic targets in these patients. 2) Plasmatic DPPIV is an independent prognostic factor in survival of CRC patients. The determination of DPPIV activity levels in the plasma may be a safe, minimally invasive and inexpensive way to define the aggressiveness of CRC in daily practice.

Glycosylation characteristics of colorectal cancer

Glycans on proteins and lipids are known to alter with malignant transformation. The study of these may contribute to the discovery of biomarkers and treatment targets as well as understanding of cancer biology. We here describe the change of glycosylation specifically defining colorectal cancer with view on N-glycans, O-glycans, and glycosphingolipid glycans in colorectal cancer cells and tissues as well as patient sera. Glycan alterations observed in colon cancer include increased β1,6-branching and correlating higher abundance of (poly-)N-acetyllactosamine extensions of N-glycans as well as an increase in (truncated) high-mannose type glycans, while bisected structures decrease. Colorectal cancer-associated O-glycan changes are predominated by reduced expression of core 3 and 4 glycans, whereas higher levels of core 1 glycans, (sialyl) T-antigen, (sialyl) Tn-antigen, and a generally higher density of O-glycans are observed. Specific changes for glycosphingolipid glycans are lower abundances of disialylated structures as well as globo-type glycosphingolipid glycans with exception of Gb3. In general, alterations affecting all discussed glycan types are increased sialylation, fucosylation as well as (sialyl) Lewis-type antigens and type-2 chain glycans. As a consequence, interactions with glycan-binding proteins can be affected and the biological function and cellular consequences of the altered glycosylation with regard to tumorigenesis, metastasis, modulation of immunity, and resistance to antitumor therapy will be discussed. Finally, analytical approaches aiding in the field of glycomics will be reviewed with focus on binding assays and mass spectrometry.

Assessment of the value of carcinoembryonic antigen reduction ratio as a prognosis factor in rectal cancer

BACKGROUND

Carcinoembryonic antigen (CEA) is the most widely used tumor marker for colorectal cancer. This study aimed to investigate the role of CEA reduction ratio after preoperative chemoradiotherapy (CRT).

METHODS

We enrolled 284 patients who underwent preoperative CRT followed by radical surgical resection. Patients were divided into 3 groups: serum CEA levels before CRT (pre-CRT CEA) less than 5 ng/mL (group 1); pre-CRT CEA of 5 ng/mL or more with CEA reduction ratio of 50% or more (group 2); and pre-CRT CEA of 5 ng/mL or more with CEA reduction ratio less than 50% (group 3).

RESULTS

The 5-year disease-free survival (DFS) rate was not different between groups 1 (71.8%) and 2 (69.4%) but was significantly lower in group 3 (49.5%). CEA group, lymph node status after CRT (ypN) stage, and histologic type were independent prognostic factors for DFS on multivariate analysis.

CONCLUSIONS

CEA reduction ratio might be an independent prognostic factor for DFS in rectal cancer patients treated with preoperative CRT and radical surgery.

Future directions for monitoring treatment response in colorectal cancer

Treatment of advanced colon and rectal cancer has significantly evolved with the introduction of neoadjuvant chemoradiation therapy so much that, along with more effective chemotherapy regimens, surgery has been considered unnecessary among some institutions for select patients. The tumor response to these treatments has also improved and ultimately has been shown to have a direct effect on prognosis. Yet, the best way to monitor that response, whether clinically, radiologically, or with laboratory findings, remains controversial. The authors' aim is to briefly review the options available and, more importantly, examine emerging and future options to assist in monitoring treatment response in cases of locally advanced rectal cancer and metastatic colon cancer.

Tumor markers in colorectal cancer, gastric cancer and gastrointestinal stromal cancers: European group on tumor markers 2014 guidelines update

Biomarkers currently play an important role in the detection and management of patients with several different types of gastrointestinal cancer, especially colorectal, gastric, gastro-oesophageal junction (GOJ) adenocarcinomas and gastrointestinal stromal tumors (GISTs). The aim of this article is to provide updated and evidence-based guidelines for the use of biomarkers in the different gastrointestinal malignancies. Recommended biomarkers for colorectal cancer include an immunochemical-based fecal occult blood test in screening asymptomatic subjects ≥50 years of age for neoplasia, serial CEA levels in postoperative surveillance of stage II and III patients who may be candidates for surgical resection or systemic therapy in the event of distant metastasis occurring, K-RAS mutation status for identifying patients with advanced disease likely to benefit from anti-EGFR therapeutic antibodies and microsatellite instability testing as a first-line screen for subjects with Lynch syndrome. In advanced gastric or GOJ cancers, measurement of HER2 is recommended in selecting patients for treatment with trastuzumab. For patients with suspected GIST, determination of KIT protein should be used as a diagnostic aid, while KIT mutational analysis may be used for treatment planning in patients with diagnosed GISTs.

Real-world cost-effectiveness of oxaliplatin in stage III colon cancer: a synthesis of clinical trial and daily practice evidence

OBJECTIVES

Previous cost-effectiveness analyses of oxaliplatin have been based on randomised trials whereas current Dutch policy requires evidence from daily practice. The objective of this study was to examine the real-world cost-effectiveness of oxaliplatin plus fluoropyrimidines (FL) versus FL-only as adjuvant treatment of stage III colon cancer.

METHODS

A Markov model was developed to estimate lifetime cost and quality-adjusted life-years from a hospital perspective. The effectiveness of the oxaliplatin arm was modelled by combining published efficacy data from the pivotal clinical registration trial (MOSAIC trial) with real-world (RW) data from a Dutch population-based observational study. RW patients were categorised into "eligible" or "ineligible", depending on whether the patients fulfilled the MOSAIC trial eligibility criteria. Ineligible RW patients (18 %) had a poorer prognosis than eligible RW patients (82 %) and MOSAIC trial patients. The effectiveness of the comparator was modelled using MOSAIC trial results. All cost inputs were based on RW patients and reported in Euro 2012. Cost-effectiveness analyses were performed for four different scenarios: (1) cost-effectiveness analyses based on MOSAIC trial patients; (2) cost-effectiveness analyses using MOSAIC and eligible RW patients; (3) cost-effectiveness analyses using MOSAIC and both eligible and ineligible RW patients, assuming oxaliplatin had an equal effect in ineligible and eligible patients; (4) cost-effectiveness analyses using MOSAIC and both eligible and ineligible RW patients, assuming oxaliplatin had no effect amongst ineligibles. For each scenario, univariate and probabilistic sensitivity analyses were undertaken.

RESULTS

MOSAIC trial patients and eligible RW patients treated with oxaliplatin had comparable 2-year disease-free survivals (79.5 vs. 78.4 %). Oxaliplatin showed an incremental QALY gain of 1.02, 1.13, 1.17 and 0.93 and incremental cost of <euro>9,961, <euro>11,055, <euro>9,814 and <euro>11,854 in scenarios 1-4, respectively. The corresponding incremental cost-effectiveness ratios (ICERs) were <euro>9,766, <euro>9,783, <euro>8,388 and <euro>12,746 in scenarios 1-4, respectively. In all scenarios, univariate and probabilistic sensitivity analyses indicated that the ICERs are acceptable and robust under a wide range of model assumptions.

CONCLUSIONS

The ICERs of the different scenarios that resulted from combining MOSAIC trial data with data from Dutch daily practice all suggest that FL + oxaliplatin is cost-effective versus FL alone in the adjuvant treatment of colon cancer. This article illustrates how one could design and implement a real-world cost-effectiveness study to yield internally valid results that could also be generalisable.

Individualized Cutoff Value of the Preoperative Carcinoembryonic Antigen Level is Necessary for Optimal Use as a Prognostic Marker

Purpose

Carcinoembryonic antigen (CEA) is an important prognostic marker in colorectal cancer (CRC). However, in some stages, it does not work. We performed this study to find a way in which preoperative CEA could be used as a constant prognostic marker in harmony with the TNM staging system.

Methods

Preoperative CEA levels and recurrences in CRC were surveyed. The distribution of CEA levels and the recurrences in each TNM stage of CRC were analyzed. An optimal cutoff value for each TNM stage was calculated and tested for validity as a prognostic marker within the TNM staging system.

Results

The conventional cutoff value of CEA (5 ng/mL) was an independent prognostic factor on the whole. However, when evaluated in subgroups, it was not a prognostic factor in stage I or stage III of N2. A subgroup analysis according to TNM stage revealed different CEA distributions and recurrence rates corresponding to different CEA ranges. The mean CEA levels were higher in advanced stages. In addition, the recurrence rates of corresponding CEA ranges were higher in advanced stages. Optimal cutoff values from the receiver operating characteristic curves were 7.4, 5.5, and 4.5 ng/mL for TNM stage I, II, and III, respectively. Those for N0, N1, and N2 stages were 5.5, 4.8, and 3.5 ng/mL, respectively. The 5-year disease-free survivals were significantly different according to these cutoff values for each TNM and N stage. The multivariate analysis confirmed the new cutoff values to be more efficient in discriminating the prognosis in the subgroups of the TNM stages.

Conclusion

Individualized cutoff values of the preoperative CEA level are a more practical prognostic marker following and in harmony with the TNM staging system.

AJCC Cancer Staging Manual 7th edition criteria for colon cancer: do the complex modifications improve prognostic assessment?

BACKGROUND

The 7th edition of the AJCC Cancer Staging Manual (AJCC-7) includes substantial changes for colon cancer (CC), which are particularly complex in patients with stage II and III disease. We used a national cancer database to determine if these changes improved prediction of survival.

STUDY DESIGN

The database of the Surveillance, Epidemiology and End Results Program was queried to identify patients with pathologically confirmed stage I to III CC diagnosed between 1988 and 2008. Colon cancer was staged by the 6(th) edition of the AJCC Cancer Staging Manual (AJCC-6) and then restaged by AJCC-7. Five-year disease-specific survival and overall survival were compared.

RESULTS

After all exclusion criteria were applied, AJCC-6 and AJCC-7 staging was possible in 157,588 patients (68.9%). Bowker's test of symmetry showed that the number of patients per substage was different for AJCC-6 and AJCC-7 (p < 0.001). The Akaike information criteria comparison showed superior fit with the AJCC-7 model (p < 0.001). However, although AJCC-7 staging yielded a progressive decrease in disease-specific survival and overall survival of patients with stage IIA (86.3% and 72.4%, respectively), IIB (79.4% and 63.2%, respectively), and IIC (64.9% and 54.6%, respectively) CC, disease-specific survival and overall survival of patients with stage IIIA disease increased (89% and 79%, respectively). Subset analysis of patients with >12 lymph nodes examined did not affect this observation.

CONCLUSIONS

The AJCC-7 staging of CC does not address all survival discrepancies, regardless of the number of lymph nodes examined. Consideration of other prognostic factors is critical for decisions about therapy, particularly for patients with stage II CC.

Clinical presentation predicts the outcome of patients with colon cancer

AIM: To elucidate the relationship between clinical presentation and outcome.

METHODS: A single institution retrospective chart review of patients admitted with the diagnosis of colon cancer. We used univariate and a multivariate analysis to identify symptoms association with mortality. An odds ratio based clinical score was created to evaluate the contribution of the quality of symptoms to outcome. Primary measure of outcome was survival.

RESULTS: During the study period, 236 patients met the inclusion criteria. Overall survival was 60.6%, mean follow-up 3.0 years. A bivariate analysis showed that increasing number of symptoms is not associated with mortality. However, a symptom-specific analysis performed using a logistic regression model controlling for age, stage and the duration of complaints revealed that the presence of melena was independently associated with mortality [P = 0.04, odds ratio (OR) 7.4], while rectal bleeding was associated with survival (P = 0.004, OR 3.9). Applying the proposed clinical score to an receiver operating characteristic curve showed that score > 1 had a strong association with mortality. The same logistic regression model was applied. The results showed that a score > 1 was an independent predictor of mortality (P < 0.001) and associated with node-positive disease (P = 0.008).

CONCLUSION: The quality of symptoms rather than quantity is correlated with outcome among patients with colon cancer. The proposed clinical scoring system may correctly predict the patient’s outcome.

Prognostic factors of stage Ⅱa colon cancer

AIM: To investigate the prognostic factors of stage Ⅱa (pT3N0M0) colon cancer.

METHODS: The demographic, clinical and laboratory data for 161 patients with stage Ⅱa colon cancer treated with curative surgery alone at Peking University Cancer Hospital from January 2004 to June 2008 were reviewed retrospectively. Eighty-four valid cases were selected in this study based on inclusive and exclusive criteria. The 3-year disease-free survival (DFS) was tested by univariate and multivariate analyses to identify prognostic factors.

RESULTS: The overall 3-year DFS for the selected 84 cases was 88.1%. The 3-year DFS for patients with elevated CEA levels was significantly lower than those with normal CEA levels (76.5% vs 95.8%, P = 0.007). Multivariate analysis demonstrated that CEA level (OR = 8.013, 95% CI 1.573-40.817, P = 0.012), expression of Ki67 (OR = 3.298, 95% CI 0.799-13.610, P = 0.099), male gender (OR = 7.212, 95% CI 1.293-40.237, P = 0.024) and anemia (OR = 6.461, 95% CI 1.537-27.151, P = 0.011) were independent prognostic factors for the 3-year DFS. Stratified analysis revealed that elevated level of CEA combined with high expression of Ki67 was associated with a poorer prognosis (3-year DFS = 70%).

CONCLUSION: Elevated preoperative serum level of CEA and high expression of Ki67 in cancer tissue are predictors of poor prognosis for stage Ⅱa colon cancer. More intensive adjuvant treatment should be considered in patients with such high risk factors.

Elevated preoperative CEA is associated with worse survival in stage I-III rectal cancer patients

Background:

The objective of this investigation was to assess whether preoperative carcinoembryonic antigen (CEA) level is an independent predictor of overall survival in rectal cancer patients.

Methods:

All patients (n=504) undergoing a resection for stage I–III rectal cancer at the Kantonsspital St Gallen were included into a database between 1991 and 2008. The impact of preoperative CEA level on overall survival was assessed using risk-adjusted Cox proportional hazard regression models and propensity score methods.

Results:

In risk-adjusted Cox proportional hazard regression analyses, preoperative CEA level (hazard ratio (HR): 1.98, 95% confidence interval (CI): 1.36–2.90, P<0.001), distance from anal verge (<5 cm: HR: 1.93, 95% CI: 1.11–3.37; P=0.039), older age (HR: 1.07, 95% CI: 1.05–1.09; P<0.001), lower body mass index (HR: 0.94, 95% CI: 0.89–0.98; P=0.006), advanced tumour stage (stage II HR: 1.41, 95% CI: 0.85–2.32; stage III HR: 2.08, 95% CI: 1.31–3.31; P=0.004), R 1 resection (HR: 5.65, 95% CI: 1.59–20.1; P=0.005) and chronic kidney disease (HR: 2.28, 95% CI: 1.03–5.04; P=0.049) were all predictors for poor overall survival.

Conclusion:

This is one of the first investigations based on a large cohort of exclusively rectal cancer patients demonstrating that preoperative CEA level is a strong predictor of decreased overall survival. Preoperative CEA should be used as a prognostic factor in the preoperative assessment of rectal cancer patients.

Tumor-infiltrating mast cells in colorectal cancer as a poor prognostic factor

The purpose of this study is to investigate the clinical/prognostic significance of tumor-infiltrating mast cells (TIMs) in patients with colorectal cancer (CRC). TIM infiltration in 325 stage I to III CRC specimens was detected by immunohistochemistry. The optimal cutpoint of TIM density was assessed by the X-tile program. TIM infiltration in CRC was significantly higher than in normal colorectal tissues. According to the X-tile program, the cutpoint for high TIM infiltration in CRC was determined when TIM density was more than 8.0 per high-power field. Correlation analysis between TIM density and clinicopathological variables demonstrated that TIM infiltration was significantly associated with gender, nodal status, and American Joint Committee on Cancer stage. Multivariate Cox regression analysis showed that high TIM infiltration was a risk factor for both overall survival and disease-free survival. Taken together, high TIM infiltration can be an independent and useful biomarker for predicting the poor survival of patients with CRC.

Role of serum carcinoembryonic antigen in the detection of colorectal cancer before and after surgical resection

AIM: To determine whether serum levels of carcinoembryonic antigen (CEA) correlate with the presence of primary colorectal cancer (CRC), and/or recurrent CRC following radical resection.

METHODS: A total of 413 patients with CRC underwent radical surgery between January 1998 and December 2002 in our department and were enrolled in this study. The median follow-up period was 69 mo (range, 3-118 mo), and CRC recurrence was experienced by 90/413 (21.8%) patients. Serum levels of CEA were assayed preoperatively, and using a cutoff value of 5 ng/mL, patients were divided into two groups, those with normal serum CEA levels (e.g., ≤ 5 ng/mL) and those with elevated CEA levels (> 5 ng/mL).

RESULTS: The overall sensitivity of CEA for the detection of primary CRC was 37.0%. The sensitivity of CEA according to stage, was 21.4%, 38.9%, and 41.7% for stages I-III, respectively. Moreover, for stage II and stage III cases, the 5-year disease-free survival rates were reduced for patients with elevated preoperative serum CEA levels (P < 0.05). The overall sensitivity of CEA for detecting recurrent CRC was 54.4%, and sensitivity rates of 36.6%, 66.7%, and 75.0% were associated with cases of local recurrence, single metastasis, and multiple metastases, respectively. In patients with normal serum levels of CEA preoperatively, the sensitivity of CEA for detecting recurrence was reduced compared with patients having a history of elevated CEA prior to radical resection (32.6% vs 77.3%, respectively, P < 0.05).

CONCLUSION: CRC patients with normal serum CEA levels prior to resection maintained these levels during CRC recurrence, especially in cases of local recurrence vs cases of metastasis.

High expression of CD73 as a poor prognostic biomarker in human colorectal cancer

BACKGROUND AND OBJECTIVES

To investigate the expression dynamics of CD73 and its prognostic significance in human colorectal cancer (CRC).

METHODS

CD73 expression dynamics were detected by Western blotting. Immunohistochemistry was used to examine the expression of CD73 in CRC tissues from two independent cohorts by tissue microarrays. The optimal cutpoint of CD73 expression was assessed by the X-tile program.

RESULTS

Western blotting analysis demonstrated that CD73 expression in CRC was significantly higher than in normal colorectal tissues. According to the X-tile program, the cutpoint for high expression of CD73 in CRC was determined when CD73 expression index was more than 5.9. High expression of CD73 was observed in 44.8% and 50.4% of CRC in the training and validation cohorts, respectively. Overexpression of CD73 was significantly correlated with tumor differentiation, nodal status, American Joint Committee on Cancer stage. Patients with high expression of CD73 had a poorer overall survival rate compared with patients with low expression of CD73 in both cohorts. In multivariate Cox regression analysis, overexpression of CD73 was proven to be an independent prognostic biomarker for CRC.

CONCLUSIONS

High expression of CD73 can be an independent and useful biomarker for predicting the poor survival of patients with CRC.

Detection of methylated SEPT9 in plasma is a reliable screening method for both left- and right-sided colon cancers

BACKGROUND

Methylated Septin 9 (SEPT9) is a sensitive biomarker for colorectal cancer (CRC) from peripheral blood. However, its relationship to cancer localization, guaiac-based fecal occult blood test (gFOBT) and carcinoembryonic antigen (CEA) have not been described.

METHODOLOGY/PRINCIPAL FINDINGS

Plasma samples were collected for SEPT9 analysis from patients with no evidence of disease (NED) (n=92) before colonoscopy and CRC (n=92) before surgical treatment. DNA was isolated and bisulfite-converted using Epi proColon kit 2.0. Qualitative determination was performed using Epi proColon 2.0 RT-PCR assay. Samples for gFOBT and CEA analysis were collected from NED (n=17 and 27, respectively) and CRC (n=22 and 27, respectively). SEPT9 test was positive in 15.2% (14/92) of NED and 95.6% (88/92) of CRC, including 100% (67/67) from stage II to stage IV CRC and 84% (21/25) of stage I CRC when a sample was called positive if 1 out of 3 PCR replicates was positive. In a second analysis (2 out of 3 PCR replicates) specificity improved to 99% (91/92) of NEDs, at a sensitivity of 79.3% (73/92) of SEPT9 positives in CRC. gFOBT was positive in 29.4% (5/17) of NED and 68.2% (15/22) of CRC and elevated CEA levels were detected in 14.8% (4/27) of NED and 51.8% (14/27) of CRC. Both SEPT9 (84.8%) and CEA (85.2%) showed higher specificity than gFOBT (70.6%). SEPT9 was positive in 96.4% (54/56) of left-sided colon cancer (LSCC) cases and 94.4% (34/36) of right-sided colon cancer (RSCC) cases. gFOBT was positive in 83.3% (10/12) of cases with LSCC and 50% (5/10) of cases with RSCC, elevated CEA was detected 60% (9/15) of LSCC and 41.7% (5/12) of RSCC.

CONCLUSIONS/SIGNIFICANCE

The high degree of sensitivity and specificity of SEPT9 in plasma makes it a better method to detect CRC than gFOBT and CEA, even for the more difficult to detect RSCC.