Results of a 400-patient carcinoembryonic antigen second-look colorectal cancer study

Advances in the management of peritoneal malignancies

Peritoneal surface malignancies (PSMs) are usually associated with a poor prognosis. Nonetheless, in line with advances in the management of most abdominopelvic metastatic diseases, considerable progress has been made over the past decade. An improved understanding of disease biology has led to the more accurate prediction of neoplasia aggressiveness and the treatment response and has been reflected in the proposal of new classification systems. Achieving complete cytoreductive surgery remains the cornerstone of curative-intent treatment of PSMs. Alongside centralization in expert centres, enabling the delivery of multimodal and multidisciplinary strategies, preoperative management is a crucial step in order to select patients who are most likely to benefit from surgery. Depending on the specific PSM, the role of intraperitoneal chemotherapy and of perioperative systemic chemotherapy, in particular, in the neoadjuvant setting, is established in certain scenarios but questioned in several others, although more prospective data are required. In this Review, we describe advances in all aspects of the management of PSMs including disease biology, assessment and improvement of disease resectability, perioperative management, systemic therapy and pre-emptive management, and we speculate on future research directions.

Enabling Direct Protein Detection in a Drop of Whole Blood with an "On-Strip" Plasma Separation Unit in a Paper-Based Lateral Flow Strip

Conventional paper lateral flow assays have low sensitivity and suffer from severe interference from complex human fluid sample matrices, which prevents their practical application in the testing of whole blood samples in the point-of-care settings. To solve this problem, gold nanostar@Raman reporter@silica-sandwiched nanoparticles have been developed as the surface-enhanced Raman scattering (SERS) probes for sensing transduction; and a functionalized filter membrane assembly has been designed and constructed in the paper-based lateral flow strip (PLFS) as a built-in plasma separation unit. In this "on-strip" plasma separation unit, three layers of filter membranes are stacked and surface-modified to maximize the separation efficiency and the plasma yield. As a result, the integrated PLFS has been successfully used for the detection of carcinoembryonic antigen (CEA) in 30 μL of whole blood with the assistance of a portable Raman reader, achieving a limit of detection of 1.0 ng mL^-1. In short, this report presents an inexpensive, disposable, portable, and field-deployable paper-based device as a general point-of-care testing tool for protein biomarker detection in a drop of whole blood.

CEACAM5 stimulates the progression of non-small-cell lung cancer by promoting cell proliferation and migration

Objective

To detect the expression of CEA-related cell adhesion molecule 5 (CEACAM5) in non-small-cell lung cancer (NSCLC) and explore its function in the progression and development of NSCLC.

Methods

qRT-PCR and immunohistochemistry were performed to detect CEACAM5 expression in human NSCLC tissues and cell lines. The correlation between CEACAM5 expression and the clinicopathological features of patients with NSCLC was also investigated. MTT, colony formation, wound healing, and immunoblot assays were performed to detect the functions of CEACAM5 in NSCLC cells in vitro, and immunoblotting was used to detect the effects of CEACAM5 on p38–Smad2/3 signaling.

Results

CEACAM5 expression was elevated in human NSCLC tissues and cells. We further found that CEACAM expression was correlated with clinicopathological features including T division, lymph invasion, and histological grade in patients with NSCLC. The in vitro assays confirmed that CEACAM5 depletion inhibited the proliferation and migration of NSCLC cells by activating p38–Smad2/3 signaling. We verified the involvement of CEACAM5 in the suppression of NSCLC tumor growth in mice.

Conclusion

CEACAM5 stimulated the progression of NSCLC by promoting cell proliferation and migration in vitro and in vivo. CEACAM5 may serve as a potential therapeutic target for the treatment of NSCLC.

Prevention and Treatment of Peritoneal Metastases: a Comprehensive Review

Peritoneal metastases may occur from a majority of cancers that occur within the abdomen or pelvis. When cancer spread to the peritoneal surfaces is documented, a decision regarding palliation versus an aggressive approach using cytoreductive surgery (CRS) and hyperthermic perioperative intraperitoneal chemotherapy (HIPEC) must be made. This decision is dependent on a well-defined group of prognostic indicators. In addition to treatment, prevention of peritoneal metastases may be an option. The clinical and pathologic features of a primary cancer can be used to select perioperative treatments that may prevent cancer cells within the abdomen and pelvis from progressing to established peritoneal metastases. In some clinical situations with appendiceal and colorectal cancers, the clinical or histopathologic features may indicate that second-look surgery plus perioperative chemotherapy should occur. Peritoneal metastases should always be considered by the multidisciplinary team for treatment or prevention.

Peritoneal Metastases from Gastrointestinal Cancer

PURPOSE OF REVIEW

Peritoneal metastases may occur from a majority of cancers that occur within the abdomen or pelvis. When cancer spread to the peritoneal surfaces is documented, a decision regarding palliation vs. an aggressive approach using cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy must be made. The perioperative chemotherapy may be hyperthermic intraperitoneal chemotherapy (HIPEC) administered in the operating room or early postoperative intraperitoneal chemotherapy (EPIC) administered in the first 4 or 5 postoperative days.

RECENT FINDINGS

This decision is dependent on a well-defined group of prognostic indicators. In addition to treatment, the clinical and pathologic features of a primary cancer can be used to select perioperative treatments that may prevent cancer cells within the abdomen and pelvis from progressing to established peritoneal metastases. In some clinical situations with appendiceal and colorectal cancers, the clinical or histopathologic features may indicate that second-look surgery plus perioperative chemotherapy should occur. Peritoneal metastases should always be considered for treatment or prevention.

Tumor Markers in Patients with Chronic Renal Failure

In order to evaluate the specificity of tumor markers in chronic renal failure, we have determined serum levels of carcinoembryonic antigen (CEA), carbohydrate antigen 19.9 (CA 19.9), carbohydrate antigen 50 (CA 50), alfafetoprotein (AFP), neuron-specific enolase (NSE), prostatic acid phosphatase (PAP), prostatic specific antigen (PSA), squamous cell carcinoma antigen (SCC), carbohydrate antigen 15.3 (CA 15.3) and carbohydrate antigen 125 (CA 125) in 30 patients with cronic renal failure and in 36 hemodialyzed patients without clinical evidence of neoplasia. CEA, CA 50, NSE and SCC frequently show increased serum levels, suggesting a renal metabolism, while others remain, generally, within the normal levels.

Soluble Interleukin-2 Receptors in Patients with Advanced Colorectal Carcinoma

The levels of soluble interleukin-2 receptors (sIL-2R) were measured in the serum of 52 patients with advanced colorectal carcinoma and compared to CEA and CA 19-9 levels. Twenty-five normal, age and sex-matched individuals served as controls. Seventy-five per cent of the patients had increased mean serum levels of sIL-2R (1539 ± 155 U/ml), while normal controls had mean levels of 555 ± 31 U/ml (p < 0.001). The relationship with hepatic or lymph nodal metastases showed no statistically significant difference (p=0.34 and p=0.47, respectively). Serum sIL-2R levels showed a linear correlation with CEA (p < 0.05). Patients with lower pretreatment sIL-2R levels (less than 1.200 U/ml) had a longer survival than patients with higher initial levels (more than 1.200 U/ml) (p=0.0049).

In conclusion, the present work shows that the serum levels of sIL-2R: a) are elevated in patients with advanced colorectal cancer, b) have no relationship with the type of metastases, c) correlate with serum CEA and d) have a prognostic value for survival.

A Prospective Study of Comparing Multi-Gene Biomarker Chip and Serum Carcinoembryonic Antigen in the Postoperative Surveillance for Patients with Stage I-III Colorectal Cancer

Background

Circulating biomarkers can predict clinical outcomes in colorectal cancer patients. The aim of the study was to evaluate the feasibility of our multigene biomarker chip for detecting circulating tumor cells for postoperative surveillance of stage I–III colorectal cancer patients.

Materials and Methods

In total, 298 stage I–III colorectal cancer patients were analyzed after curative resection between June 2010 and October 2014. During each follow-up, a postoperative surveillance strategy, including ESMO Guidelines Working Group recommendations and the biochip, was used.

Results

After a 28.4-month median follow-up, 48 (16.1%) patients had postoperative relapse. Univariate analysis revealed that the postoperative relapse risk factors were rectal tumor, perineural invasion, elevated preoperative and postoperative serum carcinoembryonic antigen levels, and positive biochip results (all P < 0.05). Multivariate analyses revealed that postoperative relapse correlated significantly with elevated postoperative serum carcinoembryonic antigen levels (odds ratio = 4.136, P = 0.008) and positive biochip results (odds ratio = 66.878, P < 0.001). However, the sensitivity (P = 0.003), specificity (P = 0.003), positive (P = 0.002) and negative (P = 0.006) predictive values, and accuracy (P < 0.001) of the biochip for predicting postoperative relapse were significantly higher than those of elevated postoperative serum carcinoembryonic antigen levels. Moreover, the median lead time between positive biochip result and postoperative relapse detection was significantly earlier than that between elevated postoperative serum carcinoembryonic antigen level and postoperative relapse detection (10.7 vs. 2.8 months, P < 0.001). Furthermore, positive biochip results correlated strongly with lower disease-free survival and overall survival of colorectal cancer patients (both P < 0.001).

Conclusion

Compared with conventional serum carcinoembryonic antigen detection, our multigene chip aided more accurate and earlier prediction of postoperative relapse during stage I–III colorectal cancer patient surveillance. In clinical practice, this biochip may facilitate early postoperative relapse diagnosis in colorectal cancer 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).

Emerging Role and Targeting of Carcinoembryonic Antigen-related Cell Adhesion Molecule 6 (CEACAM6) in Human Malignancies

Background: Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is a member of the CEA family of cell adhesion proteins that belong to the immunoglobulin superfamily. CEACAM6 is normally expressed on the surface of myeloid (CD66c) and epithelial surfaces. Stiochiomertic expression of members of the CEA family (CEACAM1, 5, 6, 7) on epithelia maintains normal tissue architecture through homo-and hetero-philic interactions. Dysregulated over-expression of CEACAM6 is oncogenic, is associated with anoikis resistance and an invasive phenotype mediated by excessive TGFβ, AKT, FAK and SRC signaling in human malignancies. Methods: Extensive literature review through PubMed was conducted to identify relevant preclinical and clinical research publications regarding CEACAM6 over the last decade and was summarized in this manuscript. Results: CEACAM5 and 6 are over-expressed in nearly 70% of epithelial malignancies including colorectal cancer (CRC), pancreatic ductal adenocarcinoma (PDA), hepatobiliary, gastric, breast, non-small cell lung and head/neck cancers. Importantly, CEACAM6 is a poor prognostic marker in CRC, while its expression correlates with tumor stage, metastasis and post-operative survival in PDA. CEACAM6 appears to be an immune checkpoint suppressor in hematologic malignancies including acute lymphoblastic leukemia and multiple myeloma. Several therapeutic monoclonal antibodies or antibody fragments targeting CEACAM6 have been designed and developed as a targeted therapy for human malignancies. A Llama antibody targeting CEACAM6 is being evaluated in early phase clinical trials. Conclusion: This review focuses on the role of CEACAM6 in the pathogenesis and signaling of the malignant phenotype in solid and hematologic malignancies and highlights its potential as a therapeutic target for anti-cancer therapy.

Correlation of CEA but not CA 19-9 as serum biomarkers of disease activity in a case of metastatic rectal adenocarcinoma

We present the case of a 62-year-old-man with moderately differentiated adenocarcinoma of the rectum. This patient underwent neoadjuvant chemoradiation and surgical resection followed by adjuvant chemotherapy. After completing therapy, this patient had 2 instances of CEA elevation, both of which preceded the discovery of recurrent disease. While on treatment for these recurrences, CA 19-9 increased rapidly to 4,405. This CA 19-9 elevation persisted for approximately 4 months in the absence of clinical, radiographic or additional serologic evidence of progressive disease before returning to baseline. Shortly after this tumor marker normalized, a small area of locally recurrent disease was discovered. This case highlights the utility and pitfalls of colorectal cancer disease monitoring with CEA and CA 19-9. The differential diagnosis of CA 19-9 elevation is discussed in this report.

CEACAM6 as detected by the AP11 antibody is a marker notable for mucin-producing adenocarcinomas

A new monoclonal antibody recognizing CEACAM6, which we named AP11, was generated by immunizing BALB/c mice with phytohemagglutinin-activated human peripheral blood mononuclear cells. This study aims to evaluate whether CEACAM6 can serve as a tumor marker using AP11. We examined the expression of CEACAM6 with AP11 in 11 human carcinoma cell lines by flow cytometry and 439 human tissues including 282 tumor tissues and 157 normal tissues by immunohistochemistry. CEACAM6 epitope recognized by AP11 was well preserved in formalin-fixed and paraffin-embedded tissues. Adenocarcinomas of the stomach (86 %), colorectum (95 %), pancreas (100 %), and lung (83 %), urinary bladder (100 %), and mucinous ovarian tumors (88 %) had a high rate of CEACAM6 immunoreactivity. We observed a variable expression of CEACAM6 in hepatocellular carcinomas (35 %), squamous cell carcinomas of the lung (60 %), renal cell carcinomas (14 %), urothelial carcinomas (13 %), serous carcinomas of the ovary (17 %), and breast carcinomas (11 %). Small-cell carcinomas of the lung, prostatic adenocarcinomas, papillary thyroid carcinomas, malignant melanomas, giant cell tumors, and osteosarcomas were negative for CEACAM6. All normal tissues of various organs were negative for CEACAM6. In conclusion, CEACAM6 as detected by AP11, may serve as a marker for mucin-producing adenocarcinomas of the gastrointestinal tract and ovary as well as non-small cell lung cancer. Thus, AP11 represents a valuable diagnostic tool for detecting CEACMA6-positive cancers.

Colorectal cancer: prevention and management of metastatic disease

This paper compared the similarities and differences of the two most common types of colorectal cancer metastases. The treatment of liver metastases by surgery combined with systemic chemotherapy was explained. The different natural history of liver metastases as compared to peritoneal metastases and the possibility for prevention of peritoneal metastases were emphasized. Perioperative cancer chemotherapy or second-look surgery must be considered as individualized treatments of selected patients who have small volume peritoneal metastases or who are known to be at risk for subsequent disease progression on peritoneal surfaces. However, the fact that peritoneal metastases, when diagnosed in the follow-up of colorectal cancer patients, can be cured with a combination of cytoreductive surgery and hyperthermic perioperative chemotherapy cannot be ignored. Careful follow-up and timely intervention in colorectal cancer patients with progressive disease are a necessary part of the management strategies recommended by the multidisciplinary team. After a critical evaluation of the data currently available, these strategies for prevention and management of colorectal metastases are presented as the author's recommendations for a high standard of care. As more information becomes available, modifications may be necessary.

Physician follow-up and observation of guidelines in the post treatment surveillance of colorectal cancer

BACKGROUND

Guidelines for post resection surveillance of colorectal cancer recommend a collection of the patient's history and physical examination, testing for carcinoembryonic antigen (CEA), and colonoscopy. No consistent guidelines exist for the use of abdominal computed tomography (CT) and position emission tomography (PET)/PET-CT. The goal of our study was to describe current trends, the impact of oncologic follow-up on guideline adherence, and the patterns of use of nonrecommended tests.

METHODS

We used Texas Cancer Registry-Medicare-linked data (2000-2009) to identify physician visits, CEA testing, colonoscopy, abdominal CT, and PET/PET-CT scans in patients ≥ 66 years old with stage I-III colorectal cancer who underwent curative resection. Compliance with guidelines was assessed with a composite measure of physician visits, CEA tests, and colonoscopy use from start of surveillance.

RESULTS

In patients who survived 3 years, the overall compliance with guidelines was 25.1%. In patients seen regularly by a medical oncologist, compliance with guidelines increased to 61.5% compared with 8.8% for those not seen by a medical oncologist regularly (P < .0001). The use of abdominal CT and PET/PET-CT increased from 57.5% and 9.5%, respectively, in 2001 to 65.8% and 24.6% (P < .0001) in 2006. Patients who saw a medical oncologist were more likely to get cross-sectional imaging than those who did not (P < .0001).

CONCLUSION

Compliance with current minimum guidelines for post treatment surveillance of colorectal cancer is low and the use of nonrecommended testing has increased over time. Both compliance and use of nonrecommended tests are markedly increased in patients seen by a medical oncologist. The comparative effectiveness of CT and PET/PET-CT in the surveillance of colorectal cancer patients needs further examination.

Detection of resectable recurrences in colorectal cancer patients with 2-[18F]fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography

PURPOSE

To evaluate the usefulness of 2-[(18)F]fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) in the early detection of resectable recurrences of colorectal cancer (CRC) and the impacts on the clinical disease management.

METHODS

FDG-PET/CT was performed on patients with elevated serum carcinoembryonic antigen (CEA) levels >5 ng/mL (Group 1) or suspicious recurrences without rise in serum CEA levels (Group 2). The results were analyzed on the basis of histological data, disease progression, and/or clinical follow-up. Recurrence was defined as evidence of recurrent lesions within 6 months of the FDG-PET/CT scan. Resectable recurrences and changes in management were calculated based on medical records.

RESULTS

In our study, 128 consecutive FDG-PET/CT analyses (n=49 in Group 1 and n=79 in Group 2) were performed on 96 recruited patients. Recurrences were proven in 63. The overall sensitivity, specificity, and accuracy of FDG-PET/CT were 98.4%, 89.2%, and 93.8%, respectively, and were 100%, 88.9%, and 95.9% in Group 1 and 96.9% and 89.4% and 92.4% in Group 2, respectively. Surgical resections were performed in 38.7% (12/31) of Group 1 patients and 53.1% (17/32) of Group 2 patients. FDG-PET/CT induced changes in planned management in 48.4% (62/128) of all patients, which included 63.3% (31/49) of Group 1 patients and 39.2% (31/79) of Group 2 patients (p=0.008). After a follow-up, 3.4% (1/29) of patients who underwent surgical resection of recurrent lesions and 34.3% (11/34) patients who did not undergo resection died at the end of study (p=0.004).

CONCLUSIONS

The surgical resection of limited recurrent disease, as determined by FDG-PET/CT, improves the survival of CRC patients. FDG-PET/CT should be performed not only in patients with elevated serum CEA levels, but also in those in whom recurrences are suspected to improve the early detection of resectable disease.

Patients at risk for peritoneal surface malignancy of colorectal cancer origin: the role of second look laparotomy

Peritoneal surface malignancy (PSM) is a frequent occurrence in the natural history of colorectal cancer (CRC). Although significant advances have been made in screening of CRC, similar progress has yet to be made in the early detection of PSM of colorectal cancer origin. The fact that advanced CRC can be confined to the peritoneal surface without distant dissemination forms the basis for aggressive multi-modality therapy consisting of cytoreductive surgery (CRS) plus hyperthermic intra-peritoneal chemotherapy (HIPEC), and neoadjuvant and/or adjuvant systemic therapy. Reported overall survival with complete CRS+HIPEC exceeds that of systemic therapy alone for the treatment of PSM from CRC, underscoring the advantage of this multi-modality therapeutic approach. Patients with limited peritoneal disease from CRC can undergo complete cytoreduction, which is associated with the best reported outcomes. As early or limited peritoneal carcinomatosis is undetectable by conventional imaging modalities, second look laparotomy is an important means to identify disease in high-risk patients at a stage most amenable to complete cytoreduction. This review focuses on the identification of patients at risk for PSM from CRC and discusses the role of second look laparotomy.

Early intervention for treatment and prevention of colorectal carcinomatosis: a plan for individualized care

The benefits that are reported in patients who have carcinomatosis from colorectal cancer increase as the extent of disease within the abdomen and pelvis decreases. To optimize treatments that involve cytoreductive surgery and perioperative chemotherapy, early intervention is necessary. Strategies to improve the results of carcinomatosis treatments include second-look surgery and hyperthermic intraperitoneal chemotherapy in patients at high risk for recurrence. Alternatively, the use of hyperthermic intraperitoneal chemotherapy can be used to treat or prevent carcinomatosis at the time of primary colorectal cancer resection in selected patients.

Proactive management of peritoneal metastases from colorectal cancer: the next logical step toward optimal locoregional control

SUMMARY Although surgery for colorectal cancer has improved over the last decade, locoregional recurrence and peritoneal metastases continue as a mechanism of surgical treatment failure in 10–20% of patients. These patients have a dismal prognosis. Clinical information is available in order to identify patients who are at high risk for locoregional recurrence and peritoneal metastases. These patients, once identified, should be offered new treatment options shown to be of benefit in selected patients. Using perioperative chemotherapy at the time of colorectal cancer resection improves locoregional control and diminishes peritoneal metastases. Also, in patients at high risk, a proactive second-look surgery utilizing peritonectomy and hyperthermic intraperitoneal chemotherapy is of benefit, with reasonable morbidity and mortality.

Review of biomarkers in colorectal cancer

AIM

Advances in molecular technology have resulted in the discovery of many putative biomarkers relevant to colorectal cancer (CRC).

METHOD

Literature searches were performed on PubMed and EMBASE using the words 'colorectal cancer', AND 'biomarkers OR markers'. Biomarkers that are either currently in clinical use or have potential clinical use were identified.

RESULTS

Most potential markers are in the discovery phase waiting to undergo clinical validation. Hypermethylation of the plasma septin-9 gene shows promise as a nonstool-based screening tool. Hypermethylation of the DYPD gene (encodes the enzyme dihydropyrimidine dehydrogenase) and variation of the uridine diphosphate-glucuronosyltransferase 1A (UGT1A1) gene have predictive value for side effects and the efficacy of 5-fluoruracil and irinotecan, respectively. Mismatch repair protein immunohistochemistry is able to predict response to 5-fluorouracil, and the KRAS (Kirsten rat sarcoma viral oncogene) and B-RAF (v-RAF murine sarcoma viral oncogene homolog B1) somatic gene mutation status can predict the response to anti-epidermal growth factor receptor therapy.

CONCLUSION

Recent advances indicate that the widespread use of biomarkers may herald the next major advance in the diagnosis and management of CRC.

Dynamic expression of CEACAM7 in precursor lesions of gastric carcinoma and its prognostic value in combination with CEA

Background

The significance of carcinoembryonic antigen-related cell adhesion molecule 7 (CEACAM7) expression in gastric carcinoma and precancerous lesions and its correlation with CEA expression has rarely been previously investigated.

Methods

CEACAM7 and CEA expression was detected by immunohistochemistry in consecutive sections of 345 subjects with gastric carcinoma and precancerous lesions. Laser confocal analysis was performed to determine CEACAM7 and CEA localization. Correlation between CEACAM7 and CEA expression with clinicopathological parameters was statistically analyzed.

Results

CEACAM7 expression correlated with pathologic grading (P = 0.006), Lauren's classification (P = 0.023), and CEA expression (Spearman R = 0.605, P < 0.001) in gastric carcinoma. CEACAM7 co-localized with CEA predominantly in the cytoplasmic membrane of cancerous cells. CEA expression was correlated with lymph node metastasis (P = 0.031). CEACAM7 and CEA expression increased progressively from precursor lesions to gastric carcinomas. A combination of CEACAM7 and CEA expression was determined to be an independent predictor for patients with gastric carcinoma by multivariate analysis (P = 0.001).

Conclusions

CEACAM7 expression correlates with tumor differentiation and CEA expression in gastric carcinoma. CEACAM7 and CEA expression may synergistically promote gastric carcinogenesis. Combined CEACAM7 and CEA expression analysis can be a useful postoperative predictor for patients with gastric carcinoma.

The Role of High Frequency Dynamic Threshold (HiDT) Serum Carcinoembryonic Antigen (CEA) Measurements in Colorectal Cancer Surveillance: A (Revisited) Hypothesis Paper

Following curative treatment for colorectal cancer (CRC), 30% to 50% of patients will develop recurrent disease. For CRC there are several lines of evidence supporting the hypothesis that early detection of metachronous disease offers a second opportunity for cure. This paper revisits the potential role of serum carcinoembryonic antigen (CEA) in follow-up. A comprehensive review of the literature (1978–2008) demonstrates that the initial promise of serum CEA as an effective surveillance tool has been tarnished through perpetuation of poorly designed studies. Specific limitations included: testing CEA as only an ‘add-on’ diagnostic tool; lack of standardization of threshold values; use of static thresholds; too low measurement frequency. Major changes in localizing imaging techniques and treatment of metastatic CRC further cause a decrease of clinical applicability of past trial outcomes. In 1982, Staab hypothesized that the optimal benefit of serum CEA as a surveillance tool is through high-frequency triage using a dynamic threshold (HiDT). Evidence supporting this hypothesis was found in the biochemical characteristics of serum CEA and retrospective studies showing the superior predictive value of a dynamic threshold. A multi-centred randomized phase III study optimizing the usage of HiDT against resectability of recurrent disease is commencing recruitment in the Netherlands.

Positron emission tomography and colorectal cancer

Colorectal cancer (CRC) is a major cause of cancer-related morbidity and mortality. Molecular imaging using positron emission tomography (PET) is now an integral part of multidisciplinary cancer care. In this review, we discuss the role of PET in CRC including well established indications in the assessment of recurrent disease and emerging applications such as initial staging, monitoring therapy efficacy and using PET for radiotherapy planning. With rapid advancement in imaging technology, we also discuss the future potential of combining PET and magnetic resonance imaging and the use of novel radiotracers.

Revised guidelines for second-look surgery in patients with colon and rectal cancer

Proper indications for a second surgical intervention in patients with colorectal cancer have always been a controversial subject. Surgeons find benefit in a second-look operation where a limited extent of cancer is discovered and resected with negative margins. However, a negative exploratory laparotomy or an intervention that is unable to achieve an R0 resection provides little or no benefit. Unfortunately, this type of intervention may place the patient in a worse condition, leading to morbidity or mortality. This manuscript attempts to define clinical parameters of primary colorectal cancer that are associated with a pattern of recurrence and that can be definitively addressed by second-look surgery. Also, new surgical technologies that may assist in achieving a potentially curative resection of local-regional recurrence are described. Cytoreductive surgery with peritonectomy and perioperative intraperitoneal chemotherapy with hyperthermia is presented as a new treatment option for reoperative surgery. A new management plan utilized in patients at high risk for local-regional recurrence may result in a high likelihood of conversion of a second-look cancer-positive patient to a long-term survivor.

Second-look surgery for colorectal cancer: revised selection factors and new treatment options for greater success

Proper indications for second-look surgery in patients with colorectal cancer have always been a controversial subject. The surgical literature suggests benefit in a reoperation, where a limited extent of cancer is discovered and then resected with negative margins. However, patients are often subjected to a negative exploratory laparotomy or an intervention that is unable to achieve an R-0 resection; in these circumstances, little or no benefit occurs. Unfortunately, an unsuccessful repeat intervention may place the patient in a worse condition, especially if morbidity occurs. This paper seeks to identify the clinical parameters of a primary colorectal cancer and a followup plan that are associated with cancer recurrence that can be definitively addressed by the second look surgery. New surgical technologies, including cytoreductive surgery with peritonectomy and perioperative intraperitoneal chemotherapy with hyperthermia, are suggested for use in this group of patients. This new management strategy used in patients with local-regional recurrence may result in a high proportion of patients converted from a second-look positive patient to a long-term survivor.

Performance of FDG PET/CT in postoperative colorectal cancer patients with a suspected recurrence and a normal CEA level

PURPOSE

The performance of 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography/computed tomography (FDG PET/CT) has been not established for the evaluation of recurrent colorectal cancer. The aim of this study was to evaluate the diagnostic value of FDG PET/CT in postoperative colorectal cancer patients with normal carcinoembryonic antigen (CEA) levels.

METHODS

This retrospective study was conducted on 63 FDG PET/CT cases, involving postoperative colorectal cancer patients suspected of having recurrent or metastatic lesions with normal CEA levels. The diagnostic performance of FDG PET/CT was evaluated based on diverse suspected conditions, using physical examination, a conventional imaging work-up, and endoscopy. Histopathology, a clinical imaging work-up (including an FDG PET/CT examination), and determination of tumor marker levels during the follow-up served as the reference standard.

RESULTS

The sensitivity, specificity, and accuracy for FDG PET/CT were 95, 76.6, and 88.8% for a lesion-by-lesion analysis, and 96.3, 86.1, and 90.5% for a case-by-case analysis, respectively. Three false-negative lesions among 107 suspected recurrent findings were identified as compared with nine false-positive lesions. For radiologically suspected recurrent or metastatic conditions, FDG PET/CT diagnostic performance was superior to radiological image modalities, for both lesion-by-lesion and case-by-case analyses. On follow-up of patients with normal CEA levels, but high CA19-9 levels, the use of FDG PET/CT detected true-positive findings in 63.3% of cases.

CONCLUSION

FDG PET/CT is a valuable tool to distinguish recurrence or metachronous tumor from postoperative changes or other benign lesions in postoperative colorectal cancer patients with normal CEA levels and radiologically or clinically suspicious lesions.

Reoperation for recurrent colorectal cancer

Recurrence of colorectal carcinoma represents a significant challenge. As the majority of recurrences involve more than just the anastomosis, surgical resection is ordinarily a major undertaking. Curative resection may require resection of other organs and structures, resulting in complex reconstructive procedures and substantial morbidity. In addition, carefully selected patients with distant metastases to sites such as the liver and lungs may also undergo potentially curative resection. Long-term survival following curative surgery for recurrence, however, ranges from only 15 to 40%. In addition to resection for curative intent, some patients may benefit from palliative procedures designed to relieve symptoms. Surgery alone is not usually sufficient therapy in these patients. Chemotherapy and radiation therapy play a vital adjunctive role in the management of recurrent disease. This article strives to review the risk factors and patterns of recurrence, selection of individuals for resection of recurrent disease, and outcomes of surgical procedures.

Ability of 18F-FDG PET/CT to diagnose recurrent colorectal cancer in patients with elevated CEA concentrations

OBJECTIVE

Elevated levels of serum carcinoembryonic antigen (CEA) in patients with colorectal cancer (CRC) during follow-up suggest recurrence, which can be visualized by (18)F-FDG PET/CT. Since the magnitude of CEA elevation reflects cancer volume, the ability of PET/CT to detect recurrence in patients with only mildly elevated CEA might be limited. However, the accuracy of PET/CT in detecting recurrence associated with elevated CEA has not been fully assessed. We retrospectively evaluated the diagnostic performance of (18)F-FDG PET/CT postoperatively relative to CEA levels among patients with CRC.

METHODS

We visually assessed 75 PET/CT evaluations of 57 postoperative patients with CEA >5.0 ng/ml. Tumor volumes were also determined using image analysis software. The final diagnosis was confirmed based on histopathological findings, or at least on 6 months of clinical follow-up.

RESULTS

Two lung cancers were excluded and we finally analyzed data from 73 of the 75 PET/CT evaluations. Recurrences were diagnosed in 54 (prevalence 74%). The sensitivity and specificity of PET/CT to detect recurrence was 50/54 (93%) and 14/19 (74%), respectively. The positive and negative predictive values were 91 and 78%, respectively, and the positive and negative likelihood ratios were 3.52 and 0.10, respectively. Values for the sensitivity of PET/CT were 88 and 95%, and those for specificity were 78 and 70%, at serum CEA concentrations of 5-10 and >10 ng/ml, respectively. Serum CEA (r = 0.500, p < 0.001) significantly correlated with cancer volumes.

CONCLUSIONS

The present findings showed that (18)F-FDG PET/CT could accurately detect recurrent CRC irrespective of the elevated CEA concentration.

Carcinoembryonic Antigen in the Staging and Follow-up of Patients with Colorectal Cancer

CEA is a complex glycoprotein produced by 90% of colorectal cancers and contributes to the malignant characteristics of a tumor. It can be measured in serum quantitatively, and its level in plasma can be useful as a marker of disease. Because of its lack of sensitivity in the early stages of colorectal cancer, CEA measurement is an unsuitable modality for population screening. An elevated preoperative CEA is a poor prognostic sign and correlates with reduced overall survival after surgical resection of colorectal carcinoma. A failure of the CEA to return to normal levels after surgical resection is indicative of inadequate resection of occult systemic disease. Frequent monitoring of CEA postoperatively may allow identification of patients with metastatic disease for whom surgical resection or other localized therapy might be potentially beneficial. To identify this group, serial CEA measurement appears to be more effective than clinical evaluation or any other diagnostic modality, although its sensitivity for detecting recurrent disease is not as high for locoregional or pulmonary metastases as it is for liver metastases. Several studies have shown that a small percentage of patients followed postoperatively with CEA monitoring and who undergo CEA-directed salvage surgery for metastatic disease will be alive and disease-free 5 years after surgery. Furthermore, CEA levels after salvage surgery do appear to predict survival in patients undergoing resection of liver or pulmonary metastases. However, several authors argue that CEA surveillance is not cost-effective in terms of lives saved. In support of this argument, there is no clear difference in survival after resection of metastatic disease with curative intent between patients in whom the second-look surgery was performed on the basis of elevated CEA levels and those with other laboratory or imaging abnormalities. There is also no clear consensus on the frequency or duration of CEA monitoring, although the ASCO guidelines currently recommend every 2-3 months for at least 2 years after diagnosis. In the follow-up of patients undergoing palliative therapy, the CEA level correlates well with response, and CEA is indicative of not only response but may also identify patients with stable disease for whom there is also a demonstrated benefit in survival and symptom relief with combination chemotherapy. More recently, scintigraphic imaging after administration of radiolabeled antibodies afforded an important radionuclide technique that adds clinically significant information in assessing the extent and location of disease in patients with colorectal cancer above and beyond or complementary to conventional imaging modalities. Immunotherapy based on CEA is a rapidly advancing area of clinical research demonstrating antibody and T-cell responses.

Plasma DNA is more reliable than carcinoembryonic antigen for diagnosis of recurrent esophageal cancer

BACKGROUND

Carcinoembryonic antigen (CEA) and plasma DNA are known to be elevated in patients with esophageal cancer and are higher in patients with disseminated disease. The sensitivity and specificity of these markers in the diagnosis of recurrent esophageal cancer have not been compared.

STUDY DESIGN

Plasma DNA was measured using polymerase chain reaction in 45 patients with esophageal cancer and 44 asymptomatic volunteers. The 95(th) percentile (19 ng /mL) in the volunteers was used to define normal. Thirty-nine patients had localized cancer and underwent resection, and six had disseminated disease at operation. Plasma DNA was measured preoperatively in all patients, with serum CEA measured in 31. Plasma DNA was measured sequentially during followup in 21 patients, including 7 who developed recurrence. CEA was measured in 14 of 21 patients who had sequential plasma DNA measured and in 6 of 7 patients with recurrence. CEA levels greater than 5.0 ng/mL were used as cut-off.

RESULTS

Plasma DNA was more sensitive than CEA for detecting unresectable esophageal cancer (100% versus 40%), but it had a lower specificity (22% versus 89%). The positive predictive value (19% versus 40%) and negative predictive value (100% versus 89%) were similar for plasma DNA and serum CEA, respectively. Plasma DNA was also more sensitive than CEA in detecting recurrent esophageal cancer (100% versus 33%). The specificity and positive predictive values were 100% for both tests, but the negative predictive values were higher for plasma DNA. Plasma DNA rose before there was clinical evidence of recurrence in 67% compared with only 17% for CEA.

CONCLUSIONS

Elevated plasma DNA is an extremely reliable indicator of the presence of recurrent disease, and, in the majority of patients, it rises before clinical evidence of recurrence. In contrast, a normal CEA should be interpreted cautiously, because it does not exclude recurrent disease.

Results of a national survey among Dutch surgeons treating patients with colorectal carcinoma. Current opinion about follow-up, treatment of metastasis, and reasons to revise follow-up practice

OBJECTIVE

Follow-up after curative resection of colorectal carcinoma (CRC) has been subjected to debate concerning its effectiveness to reduce cancer mortality. Current national and international guidelines advise CEA measurements every 3 months during 3 years after surgery. The common clinical practice and opinion about follow-up for colorectal carcinoma, was evaluated by means of a survey among Dutch general surgeons.

METHOD

A web-based survey of follow-up after treatment of CRC was sent to all registered Dutch general surgeons. A reply from 246 surgeons treating patients for colorectal carcinoma in 105 out of 118 hospitals was received (response rate 91%). Questions related to actual follow-up protocol, opinion about serum CEA monitoring, liver and/or lung metastasectomy, and motivation to participate in a new trial concerning follow-up.

RESULTS

For the majority of surgeons the length of follow-up was influenced by age of the patient (62%) and physical condition (76%) prohibiting hepatic metastasectomy. The generally accepted follow-up protocol consisted of CEA measurements every 3 months in the first year and six-monthly thereafter, and ultrasound examination of the liver every 6 months. Nearly all surgeons (92%) were willing to participate in a new study of follow-up protocol.

CONCLUSION

The adherence to national guidelines for the follow-up of colorectal carcinoma is low. The indistinctness about follow-up after curative treatment of colorectal carcinoma also affects clinical practice. Recent advancements in imaging techniques, liver and lung surgery have changed circumstances, which are not yet anticipated upon in current guidelines. Renewal of follow-up based upon scientific evidence is required.

A small rise in CEA is sensitive for recurrence after surgery for colorectal cancer

OBJECTIVE

Rise in carcinoembryonic antigen (CEA) above normal limits can indicate recurrent colorectal cancer. The aim of this study was to evaluate whether a small rise in CEA, even within normal limits was a sensitive indicator of recurrence.

METHOD

150 patients aged 22-87 years were followed up for a mean of 27 months after colorectal surgery with CEA 3 and 6 monthly computerized tomography. We analysed whether a rise in CEA > 1 ng/ml correlated with recurrence of metastases.

RESULTS

Forty-six of 139 patients in final analysis had recurrent disease. A rise in CEA > 1 had a predictive value of 74% for recurrence or metastases (sensitivity 80%, specificity 86%). These findings were similar whether or not the CEA was normal preoperatively.

CONCLUSION

If CEA is measured after surgery for colorectal cancer, a rise of >1 in the patient's postoperative value is predictive for recurrence or metastases with an overall sensitivity of 80% and specificity of 86%. Previous studies have recognized the role of large rises in CEA in predicting recurrence but this study shows that small changes in CEA may be significant even if these levels would be traditionally within 'normal' limits.

The role of positron emission tomography in the management of recurrent colorectal cancer: a review

PURPOSE

Surgery remains the only option for potential cure in patients with recurrent colorectal cancer. Accurate staging modalities aid in the avoidance of futile surgery, which may result in considerable morbidity in patients with incurable disease. Current imaging techniques used in disease staging often are not sensitive enough to identify low-volume metastatic disease. This study reviews the role of positron emission tomography in the assessment of patients with suspected recurrent colorectal cancer.

METHODS

A literature search using the PubMed, MEDLINE, and Embase database was performed, locating English language articles on positron emission tomography, positron emission tomography, recurrent colon, and/or rectal cancer. The references of these papers were searched manually for further references.

RESULTS

Positron emission tomography is more sensitive and more specific than conventional diagnostic imaging for metastatic disease and local recurrence respectively. Studies confirm the superior ability of positron emission tomography scans compared with conventional diagnostic imaging in differentiating between scar tissue and invasive tumor. Positron emission tomography scanning is more sensitive and specific for the assessment of liver metastases (and probably in patients with lung metastasis) than conventional diagnostic imaging. Positron emission tomography is superior to conventional diagnostic imaging in the investigation of raised carcinoembryonic antigen in the postoperative patient and alters management in approximately 37 percent of patients with recurrent colorectal cancer. The limitations and cost effectiveness of positron emission tomography are discussed.

CONCLUSIONS

Positron emission tomography scanning is emerging as the imaging modality of choice for patients being considered for surgery for locally recurrent colorectal cancer. Positron emission tomography has the greatest impact by detecting unresectable disease and thereby averting inappropriate surgery. Despite the high set-up costs, its use seems to be cost effective.

FDG-PET in colorectal cancer

[18F]Fluorodeoxyglucose (FDG) positron emission tomography (PET) is a useful imaging tool in the evolving management of patients with colorectal carcinoma. This technique is able to measure and visualize metabolic changes in cancer cells. This feature results in the ability to distinguish viable tumor from scar tissue, in the detection of tumor foci at an earlier stage than possible by conventional anatomic imaging and in the measurement of alterations in tumor metabolism, indicative of tumor response to therapy. Nowadays, FDG-PET plays a pivotal role in staging patients before surgical resection of recurrence and metastases, in the localization of recurrence in patients with an unexplained rise in serum carcinoembryonic antigen and in assessment of residual masses after treatment. In the presurgical evaluation, FDG-PET may be best used in conjunction with anatomic imaging in order to combine the benefits of both anatomical (CT) and functional (PET) information, which leads to significant improvements in preoperative liver staging and preoperative judgment on the feasibility of resection. Integration of FDG-PET into the management algorithm of these categories of patients alters and improves therapeutic management, reduces morbidity due to futile surgery, leads to substantial cost savings and probably also to a better patient outcome. FDG-PET also appears to have great potential in monitoring the success of local ablative therapies soon after intervention and in the prediction and evaluation of response to radiotherapy, systemic therapy, and combinations thereof. This review aims to outline the current and future role of FDG-PET in the field of colorectal cancer.

Colorectal cancer follow-up: Useful or useless?

Follow-up of surgically treated colorectal cancer patients is not supported by objectively certain data. Despite the thousands of investigations reported in the scientific literature, only six randomized prospective studies and two meta-analysis of randomized studies provide data suggesting clear conclusions. Our review of the literature revealed that intensive colorectal follow-up should be performed even if the long-term survival benefit is small. The timing and investigations conducted in follow-ups diverge. The inconsistency of follow-ups is revealed by the fact that the leading USA and European societies propose different guidelines. One datum that the literature agrees on is that pancolonoscopy performed at 3-5 year intervals in colorectal cancer surgery patients supports diagnosis of adenomatous polyps and metachronous cancers. Cost analysis have shown that intensive follow-up would certainly exceed the cut-off point level set for every additional year of good quality of life.

Value of carcinoembryonic antigen and cytokeratins for the detection of recurrent disease following curative resection of colorectal cancer

AIM: To evaluate the efficacy of postoperative serial assay of carcinoembryonic antigen (CEA) and cytokeratins for the detection of recurrent disease in patients with colorectal adenocarcinoma after radical surgery.

METHODS: Between 1993 and 2000, 120 patients with colorectal adenocarcinoma underwent radical surgery in the Department of Surgical Gastroenterology, Federal University of São Paulo-Escola Paulista de Medicina, São Paulo, Brazil. Periodic postoperative evaluation was performed by assaying markers in peripheral serum, colonoscopy and imaging examination. Presence of CEA was detected using the Delfia^® method with 5 μg/L threshold, and cytokeratins using the LIA-mat^® TPA-M Prolifigen^® method with 72 U/L threshold.

RESULTS: In the first postoperative year, patients without recurrent disease had normal levels of CEA (1.5 ± 0.9 μg/L) and monoclonal tissue polypeptide antigen-M (TPA-M, 64.4 ± 47.8 U/L), while patients with recurrences had high levels of CEA (6.9 ± 9.8 μg/L, P < 0.01) and TPA-M (192.2 ± 328.8 U/L, P < 0.05). During the second postoperative year, patients without tumor recurrence had normal levels of CEA (2.0 ± 1.8 μg/L) and TPA-M (50.8 ± 38.4 U/L), while patients with recurrence had high levels of CEA (66.3 ± 130.8 μg/L, P < 0.01) and TPA-M (442.7 ± 652.8 U/L, P < 0.05). The mean follow-up time was 22.3 mo. There was recurrence in 23 cases. Five reoperations were performed without achieving radical excision. Rises in tumor marker levels preceded identification of recurrences: CEA in seven (30%) and TPA-M in eleven individuals (48%).

CONCLUSION: Intensive follow-up by serial assay of CEA and cytokeratins allows early detection of colorectal neoplasm recurrence.

Utility of 2-fluoro-2-deoxy-D-glucose positron emission tomography in managing patients of colorectal cancer with unexplained carcinoembryonic antigen elevation at different levels

PURPOSE

Serum carcinoembryonic antigen elevation without detectable relapse during colorectal cancer follow-up presents a challenge. This study was designed to evaluate the utility of fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose positron emission tomography in colorectal cancer patients with unexplained carcinoembryonic antigen elevation at different levels.

METHODS

Thirty-seven colorectal cancer patients referred for positron emission tomography after primary surgery who had serum carcinoembryonic antigen levels >5 ng/ml and negative or equivocal conventional imaging studies were analyzed. Patient status was determined by histopathology and/or clinical follow-up. Grouping as disease-free, potentially resectable, or advanced disease was performed. The management impact was defined as the percentage of patients with a true-positive positron emission tomography result.

RESULTS

The sensitivity, specificity, and accuracy of positron emission tomography for relapse detection were 89, 89, and 89 percent, respectively. The management impact was 68 percent. In 24 patients with carcinoembryonic antigen levels <25 ng/ml, positron emission tomography helped correct patient grouping in 20 patients (83 percent), including 8 in the disease-free group, 5 in the potentially resectable group, and 7 in the advanced-disease group. In 13 patients with carcinoembryonic antigen levels >25 ng/ml, positron emission tomography identified 8 patients in the advanced-disease group and 1 patient in the potentially resectable group but missed 2 patients with relapse and undergrouped 2 patients in the advanced-disease group as potentially resectable.

CONCLUSIONS

2-fluoro-2-deoxy-D-glucose positron emission tomography can help triage patients for appropriate management with unexplained carcinoembryonic antigen elevation <25 ng/ml. For patients with unexplained elevation of carcinoembryonic antigen >25 ng/ml, the utility of positron emission tomography is mainly to confirm the presence of advanced disease and occasionally to identify potentially resectable lesions.

Cytokeratins and carcinoembryonic antigen in diagnosis, staging and prognosis of colorectal adenocarcinoma

AIM: To evaluate the serum levels of cytokeratins and carcinoembryonic antigen (CEA) in diagnosis, staging and prognosis of patients with colorectal adenocarcinoma.

METHODS: The sample consisted of 169 patients. One hundred blood donors formed the control group. Radical surgery was performed on 120 patients, with an average follow-up duration of 22.3 mo. Relapses occurred in 23 individuals after an average of 18.09 mo. CEA was assayed via the Delfia^® method with a limit of 5 ng/mL. Cytokeratins were assayed via the LIA-mat^® TPA-M Prolifigen^® method with a limit of 72 U/L.

RESULTS: In the diagnosis of patients with colorectal adenocarcinoma, CEA showed a sensitivity of 56%, a specificity of 95%, a positive predictive value of 94%, a negative predictive value of 50% and an accuracy of 76.8%. TPA-M had a sensitivity of 70%, a specificity of 96%, a positive predictive value of 97%, a negative predictive value of 66% and an accuracy of 93.6%. The elevation of one of the markers was shown to have a sensitivity of 76.9%, a specificity of 91%, a positive predictive value of 93.5%, a negative predictive value of 70% and an accuracy of 83.6%. There was no variation in the levels of the markers according to the degree of cell differentiation while there was an elevation in their concentrations in accordance with the increase in neoplastic dissemination. There was a statistically significant difference between the patients with stage IV lesions and those with stages I, II and III tumors. With regard to CEA, the average level was 14.2 ng/mL in patients with stage I lesions, 8.5 ng/mL in patients with stage II lesions, 8.0 ng/mL in patients with stage III lesions and 87.7 ng/mL in patients with stage IV lesions. In relation to TPA-M, the levels were 153.1 U/L in patients with stage I tumors, 106.5 U/L in patients with stage II tumors, 136.3 U/L in patients with stage III tumors and 464.3 U/L in patients with stage IV tumors. There was a statistical difference in patients with a high CEA level in relation to a shorter survival (P<0.05). However, there was no correlation between patients with high TPA-M levels and prognostic indices of patients undergoing radical surgery.

CONCLUSION: Cytokeratins demonstrate a greater sensitivity than CEA in the diagnosis of colorectal adenocarcinoma. There is an increase in the sensitivity of the markers with tumor dissemination. Cytokeratins cannot identify the worse prognosis in patients undergoing radical surgery. Cytokeratins constitute an advance in the direction of a perfect tumor marker in the treatment of patients with colorectal cancer.

Isolated diaphragmatic metastasis originated from adenocarcinoma of the colon

Isolated diaphragmatic metastasis arising from colorectal cancer has been reported only one case in the literature presently. Here, we presented a new case and discussed the possible pathogenesis and the treatment options. A 42-year-old male patient had received anterior resection for sigmoid colon cancer. Although the increased serum CEA level was detected 20 months after the surgery, metastatic lesion could not be detected by repeated colonoscopy, CT scan, bone scan or PET scan for 35 months. We could detect a suspicious metastatic lesion on the liver by CT scan at 56 month after the surgery. During a second-look operation, we found a solitary metastasis on the diaphragm and removed it along with the 1 cm tumor-free resection margin. Although the prognosis associated with skeletal metastasis is poor, the complete resection of isolated diaphragmatic metastasis and subsequent appropriate adjuvant chemotherapy may achieve a cure the disease provided that other metastatic lesions are absent.

Jaundice secondary to isolated porta hepatis metastasis in colorectal cancer: case report and review of the literature

Colorectal cancer occurs mainly after the age of 50. The liver is the most frequent site of metastases, although isolated metastases to the porta hepatis are rarely reported in the literature. From 1924 to 1993, only 16 cases of periportal lymph nodes metastases were reported. We report a case of jaundice secondary to porta hepatis metastases from primary colorectal cancer. The appearance of symptoms was concurrent with the elevation of carcinoembryonic antigen in our case. This emphasizes the importance of polymerase chain reaction to detect the small amount of carcinoembryonic antigen transcript in blood or in peritoneal fluid before the appearance of symptoms. Polymerase chain reaction allows the prediction of high risk of recurrence and the presence of micrometastases. More trials are needed to assess the outcome after treatment by adjuvant chemotherapy for micrometastases.

The value of routine serum carcino-embryonic antigen measurement and computed tomography in the surveillance of patients after adjuvant chemotherapy for colorectal cancer

PURPOSE

This analysis aims to evaluate routine carcino-embryonic antigen (CEA) and computed tomography (CT) of thorax, abdomen, and pelvis as part of protocol-specified follow-up policy for colorectal cancer (CRC).

PATIENTS AND METHODS

Patients with resected stage II and III CRC were randomly assigned to bolus fluorouracil/leucovorin or protracted venous infusion fluorouracil. Following completion of chemotherapy, patients were seen in clinic at regular intervals for 5 years. CEA was measured at each clinic visit, and CT of thorax, abdomen, and pelvis was performed at 12 and 24 months after commencement of chemotherapy.

RESULTS

Between 1993 and 1999, 530 patients were recruited. The median follow-up was 5.6 years. Disease relapses were observed in 154 patients. Relapses were detected by symptoms (n = 65), CEA (n = 45), CT (n = 49), and others (n = 9). Fourteen patients, whose relapses were detected by CT, had a concomitant elevation of CEA and were included in both groups. The CT-detected group had a better survival compared with the symptomatic group from the time of relapse (P =.0046). Thirty-three patients (21%) proceeded to potentially curative surgery for relapse and enjoyed a better survival than those who did not (P <.00001). For patients who underwent hepatic or pulmonary metastatic resection, 13 (26.5%) were in the CT group, eight (17.8%) in the CEA group, and only two (3.1%) in the symptomatic group (CT v symptomatic, P <.001; CEA v symptomatic, P =.015).

CONCLUSION

Surveillance CT and CEA are valuable components of postoperative follow-up in stage II and III colorectal cancer.

Follow-up strategies after curative resection of colorectal cancer

Consensus is lacking as to the best strategy for following patients who have undergone definitive surgical medical treatment for colon cancer. The goal of any surveillance program should be detection of recurrent disease at a sufficiently early time to allow subsequent curative therapy. Although periodic clinical examinations, laboratory tests, radiographic imaging, and carcinoembryonic antigen (CEA) testing have been utilized as a form of surveillance, such aggressive and costly intervention has not been validated through clinical studies. Four of the five randomized trials comparing such an intensive surveillance strategy to less frequent testing have not demonstrated the intensive approach to lead to an improvement in overall survival. Furthermore, intensive testing is both costly and has been shown not to improve quality of life. Further research designing appropriate postoperative testing is needed to guide physicians and patients after the curative resection of a colorectal cancer.