Cost and effectiveness of follow-up examinations in patients with colorectal cancer resected for cure in a French population-based study

Follow-up strategy and survival for five common cancers: A meta-analysis

BACKGROUND

This meta-analysis aimed to evaluate the effectiveness of intensive follow-up after curative intent treatment for five common solid tumours, in terms of survival and treatment of recurrences.

METHODS

A systematic literature search was conducted, identifying comparative studies on follow-up for colorectal, lung, breast, upper gastro-intestinal and prostate cancer. Outcomes of interest were overall survival (OS), cancer specific survival (CSS), and treatment of recurrences. Random effects meta-analyses were conducted, with particular focus on studies at low risk of bias.

RESULTS

Fourteen out of 63 studies were considered to be at low risk of bias (8 colorectal, 4 breast, 0 lung, 1 upper gastro-intestinal, 1 prostate). These studies showed no significant impact of intensive follow-up on OS (hazard ratio, 95% confidence interval) for colorectal (0.99; 0.92-1.06), breast 1.06 (0.92-1.23), upper gastro-intestinal (0.78; 0.51-1.19) and prostate cancer (1.00; 0.86-1.16). No impact on CSS (hazard ratio, 95% confidence interval) was found for colorectal cancer (0.94; 0.77-1.16). CSS was not reported for other cancer types. Intensive follow-up increased the rate of curative treatment (relative risk; 95% confidence interval) for colorectal cancer recurrences (1.30; 1.05-1.61), but not for upper gastro-intestinal cancer recurrences (0.92; 0.47-1.81). For the other cancer types, no data on treatment of recurrences was available in low risk studies.

CONCLUSION

For colorectal and breast cancer, high quality studies do not suggest an impact of intensive follow-up strategies on survival. Colorectal cancer recurrences are more often treated locally after intensive follow-up. For other cancer types evaluated, limited high quality research on follow-up is available.

Economic Evaluations Informed Exclusively by Real World Data: A Systematic Review

Economic evaluations using Real World Data (RWD) has been increasing in the very recent years, however, this source of information has several advantages and limitations. The aim of this review was to assess the quality of full economic evaluations (EE) developed using RWD. A systematic review was carried out through articles from the following databases: PubMed, Embase, Web of Science and Centre for Reviews and Dissemination. Included were studies that employed RWD for both costs and effectiveness. Methodological quality of the studies was assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. Of the 14,011 studies identified, 93 were included. Roughly half of the studies were carried out in a hospital setting. The most frequently assessed illnesses were neoplasms while the most evaluated interventions were pharmacological. The main source of costs and effects of RWD were information systems. The most frequent clinical outcome was survival. Some 47% of studies met at least 80% of CHEERS criteria. Studies were conducted with samples of 100-1000 patients or more, were randomized, and those that reported bias controls were those that fulfilled most CHEERS criteria. In conclusion, fewer than half the studies met 80% of the CHEERS checklist criteria.

The cost-effectiveness of follow-up strategies after cancer treatment: a systematic literature review

INTRODUCTION

The cost of treatment and follow-up of cancer patients in the UK is substantial. In a budget-constrained system such as the NHS, it is necessary to consider the cost-effectiveness of the range of management strategies at different points on cancer patients' care pathways to ensure that they provide adequate value for money.

SOURCES OF DATA

We conducted a systematic literature review to explore the cost-effectiveness of follow-up strategies of patients previously treated for cancer with the aim of informing UK policy. All papers that were considered to be economic evaluations in the subject areas described above were extracted.

AREAS OF AGREEMENT

The existing literature suggests that intensive follow-up of patients with colorectal disease is likely to be cost-effective, but the opposite holds for breast cancer.

AREAS OF CONTROVERSY

Interventions and strategies for follow-up in cancer patients were variable across type of cancer and setting. Drawing general conclusions about the cost-effectiveness of these interventions/strategies is difficult.

GROWING POINTS

The search identified 2036 references but applying inclusion/exclusion criteria a total of 44 articles were included in the analysis. Breast cancer was the most common (n = 11) cancer type followed by colorectal (n = 10) cancer. In general, there were relatively few studies of cost-effectiveness of follow-up that could influence UK guidance. Where there was evidence, in the most part, NICE guidance broadly reflected this evidence.

AREAS TIMELY TO DEVELOP RESEARCH

In terms of future research around the timing, frequency and composition of follow-ups, this is dependent on the type of cancer being considered. Nevertheless, across most cancers, the possibility of remote follow-up (or testing) by health professionals other than hospital consultants in other settings appears to warrant further work.

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).

Economic studies in colorectal cancer: challenges in measuring and comparing costs

Estimates of the costs associated with cancer care are essential both for assessing burden of disease at the population level and for conducting economic evaluations of interventions to prevent, detect, or treat cancer. Comparisons of cancer costs between health systems and across countries can improve understanding of the economic consequences of different health-care policies and programs. We conducted a structured review of the published literature on colorectal cancer (CRC) costs, including direct medical, direct nonmedical (ie, patient and caregiver time, travel), and productivity losses. We used MEDLINE to identify English language articles published between 2000 and 2010 and found 55 studies. The majority were conducted in the United States (52.7%), followed by France (12.7%), Canada (10.9%), the United Kingdom (9.1%), and other countries (9.1%). Almost 90% of studies estimated direct medical costs, but few studies estimated patient or caregiver time costs or productivity losses associated with CRC. Within a country, we found significant heterogeneity across the studies in populations examined, health-care delivery settings, methods for identifying incident and prevalent patients, types of medical services included, and analyses. Consequently, findings from studies with seemingly the same objective (eg, costs of chemotherapy in year following CRC diagnosis) are difficult to compare. Across countries, aggregate and patient-level estimates vary in so many respects that they are almost impossible to compare. Our findings suggest that valid cost comparisons should be based on studies with explicit standardization of populations, services, measures of costs, and methods with the goal of comparability within or between health systems or countries. Expected increases in CRC prevalence and costs in the future highlight the importance of such studies for informing health-care policy and program planning.

Receipt of recommended surveillance among colorectal cancer survivors: a systematic review

PURPOSE

Regular surveillance decreases the risk of recurrent cancer in colorectal cancer (CRC) survivors. However, studies suggest that receipt of follow-up tests is not consistent with guidelines. This systematic review aimed to: (1) examine receipt of recommended post-treatment surveillance tests and procedures among CRC survivors, including adherence to established guidelines, and (2) identify correlates of CRC surveillance.

METHODS

Systematic searches of Medline, PubMed, PsycINFO, CINAHL Plus, and Scopus databases were conducted using terms adapted for each database's keywords and subject headings. Studies were screened for inclusion using a three-step process: (1) lead author reviewed abstracts of all eligible studies; (2) coauthors reviewed random 5 % samples of abstracts; and (3) two sets of coauthors reviewed all "maybe" abstracts. Discrepancies were adjudicated through discussion.

RESULTS

Thirty-four studies are included in the review. Overall adherence ranged from 12 to 87 %. Within the initial 12 to 18 months post-treatment, adherence to recommended office visits was 93 %. Adherence ranged from 78 to 98 % for physical exams, 18-61 % for colonoscopy, and 17-71 % for carcinoembryonic antigen (CEA) testing. By 2 to 3 years post-treatment, cumulative adherence ranged from 70 to 88 % for office visits, 89-93 % for physical exams, 49-94 % for colonoscopy, and 7-79 % for CEA testing. Between 18 and 28 % of CRC survivors received greater than recommended overall surveillance; overuse of physical exams (42 %), colonoscopy (24-76 %), and metastatic disease testing (1-29 %) was also prevalent. Studies of correlates of CRC surveillance focused on sociodemographic and disease/treatment characteristics, and patterns of association were inconsistent across studies.

CONCLUSIONS

Deviation from surveillance recommendations includes both under- and overuse. Examination of modifiable determinants is needed to inform interventions targeting appropriate and timely receipt of recommended surveillance.

IMPLICATIONS FOR CANCER SURVIVORS

Among CRC survivors, it remains unclear what modifiable psychosocial factors are associated with the observed under- and overuse of surveillance. Understanding and intervening with these psychosocial factors is critical to improving adherence to guideline-recommended surveillance and thereby reducing mortality among this group of survivors.

Alternatives for the intensive follow-up after curative resection of colorectal cancer. Potential novel biomarkers for the recommendations

Early diagnosis of recurrence and metastasis of colorectal cancer following surgery of curative intent is of vital importance in terms of survival and quality of life. The consistent implementation of appropriate patient follow-up strategy is therefore essential. Debates over the methodology, evaluation and strategy of follow-up have been known for many years, and continue today. By introducing several follow-up models, the present paper offers different options featuring certain individual, national and international, conceptual and financial aspects. Colorectal cancer is an important public health concern due to its destructive nature and frequency, it is therefore essential to develop new monitoring strategies, involving new biomarkers and extensive clinical validation. Since the recurrence rate is very high in high-risk patients, the improvement of individual patient risk estimates and the utilization of a corresponding follow-up model require broad international co-operation and common practice, along with the determination of optimal levels of evidence.

Surveillance after colorectal cancer resection: a systematic review

BACKGROUND

Surveillance programs are widely accepted as an integral part of the treatment plan provided to patients after surgical treatment of colorectal cancer. Despite an enormous amount of research performed regarding these programs, there is still uncertainty regarding what is appropriate surveillance.

OBJECTIVE

We sought to systematically review recent literature regarding outcomes achieved with different types of surveillance programs for patients with surgically treated colorectal cancer.

DATA SOURCES

A search of the PubMed database was performed to identify studies published in the English language between January 2000 and January 2010.

STUDY SELECTION

We included 2 types of studies in our systematic review: first, comparative studies where 2 or more surveillance strategies were applied and outcomes compared; second, single-cohort studies where the outcomes of a single surveillance strategy were reported.

MAIN OUTCOME MEASURES

Cancer-related outcomes included survival, recurrence detection rate, and the ability of a recurrence to be resected with curative intent.

RESULTS

Our review found 15 studies meeting our inclusion criteria. Of these, 9 were comparative (4 randomized trials) and 6 were single-cohort studies. One study reported a better survival rate among patients who received more intensive follow-up. The vast majority of recurrences occurred within 3 years.

LIMITATIONS

Our review found that the recent literature regarding the efficacy of surveillance is inconclusive, largely because of the small sample sizes and the heterogeneity in the surveillance programs and outcomes reported.

CONCLUSIONS

Future randomized trials need to focus on larger sample sizes, and experimental designs should isolate specific elements of surveillance to better understand how each element contributes to improvements in patient outcomes. Risk stratification and duration of surveillance are key elements of surveillance strategies that also deserve focused investigation.

Cost of pretherapeutic staging of patients with colorectal cancer metastases in a French population

BACKGROUND

Little is known about the economic burden of pretherapeutic staging of patients presenting colorectal cancer metastases.

OBJECTIVE

The aim of this study was to estimate the cost of pretherapeutic staging and identify cost determinants for 132 patients presenting colorectal metastases and living in the north-east of France.

METHOD

Staging cost was estimated using direct medical costs from the point of view of the French Health Insurance System. Independent factors were identified using a linear regression model, and bootstrap resampling was used to estimate unbiased standard errors and 95% confidence intervals.

RESULTS

The overall mean cost for pretherapeutic staging was estimated to be 1534€ [95% CI: 1250€-1818€]. Staging costs increased significantly with the number of medical procedures performed during the staging, and according to health care patterns (in-patient hospital stay versus out-patient episodes, public versus private care).

CONCLUSION

These results could now be used to estimate the impact of new imaging techniques on clinical practices and pretherapeutic staging costs.

Estimating the cost related to surveillance of colorectal cancer in a French population

Little is known about costs related to the surveillance of patients that have undergone curative resection of colorectal cancer. The aim of this study was to calculate the observed surveillance costs for 385 patients followed-up over a 3-year period, to estimate surveillance costs if French guidelines are respected, and to identify the determinants related to surveillance costs to derive a global estimation for France, using a linear mixed model. The observed mean surveillance cost was <euro> 713. If French recommendations were strictly applied, the estimated mean cost would vary between <euro> 680 and <euro> 1,069 according to the frequency of abdominal ultrasound. The predicted determinants of cost were: age, recurrence, duration of surveillance since diagnosis, and adjuvant treatments. For France, the surveillance cost represented 4.4% of the cost of colorectal cancer management. The cost of surveillance should now be balanced with its effectiveness and compared with surveillance alternatives.

A cost and benefit study of esophagectomy for patients with esophageal cancer

INTRODUCTION

The incidence of esophageal cancer is increasing all over the world but the cost-and-benefit of esophagectomy for esophageal cancer patients was rarely studied. The aim of this study is to compare the cost-and-benefit of esophagectomy in different stages of esophageal cancer.

MATERIALS AND METHODS

Clinical and utilization data, including medical expenses and reason for treatment, of esophageal cancer patients were collected, summed and followed up for 5 years. The patients were divided into two groups according to their treatments, with or without esophagectomy. The monthly medical expense and relative expense performance index (REPI) were then calculated. Factors influenced total and monthly medical expense and survival time were further analyzed.

RESULTS

A total of 310 esophageal cancer patients, 281 male and mean age of 64.3, were included in this study. One hundred forty-nine patients had undergone esophagectomy. The 5-year survival rate, total and monthly medical expense for two groups was 36.0% and 10.2% (p<0.001), USD $22,532.8 vs. 12,256.4 (p<0.001) and USD $2,101.65 vs. 2,033.94 (p=0.831), respectively. The REPIs in four different stages were 7.573, 2.422, 2.446 and 0.705. Both esophagectomy and tumor stage were the sole factors that could influence total and monthly medical expense respectively. Both esophagectomy and tumor stage could influence a patient's survival time.

CONCLUSIONS

Esophagectomy has better performance than non-esophagectomy for patients with stages I to III esophageal cancer. Therefore, adding economical considerations, esophagectomy is recommended for patients, at least earlier than stage III.

Serum carcinoembryonic antigen monitoring after curative resection for colorectal cancer: clinical significance of the preoperative level

AIM

We evaluated preoperative serum carcinoembryonic antigen (CEA) as a prognostic factor for colorectal cancer and determined when surveillance of this marker was useful.

METHODS

Serum CEA was measured preoperatively in 1,263 patients who underwent curative resection for colorectal cancer at 3-month intervals for the first 2 postoperative years and at 6-month intervals thereafter. Mean follow-up was 48 months (range 1-156 months).

RESULTS

The 5-year disease-free survival was less in patients with a high preoperative serum CEA level (P<0.0001). Among patients with a tumor recurrence, 38.5% had high follow-up serum CEA levels. The number of patients with high postoperative serum CEA levels exceeded the number of patients with high preoperative levels. High preoperative and follow-up serum CEA levels were independent prognostic factors for tumor recurrence (P=0.003 and P<0.001, respectively). In patients with high preoperative serum CEA levels, CEA surveillance had a 92.3% positive predictive value (PPV) and a 96.1% negative predictive value (NPV). The mean interval between postoperative serum CEA elevation and the diagnosis of a tumor recurrence [diagnostic interval (DI)] was 2.5 months (range 5-17 months). The DI was 0 in 18.8% of patients with a tumor recurrence.

CONCLUSION

High serum CEA levels preoperatively and at follow-up are prognostic factors for colorectal cancer. Postoperative serum CEA surveillance is used most effectively when patients have high preoperative serum CEA levels. Considering the DI of 0 in 18.8% of the patients, the current CEA surveillance schedule might be changed.

Serum p53 antibody as tumor marker for follow-up of colorectal cancer after curative resection

BACKGROUND

No large-scale studies have examined the use of serial measurements of serum p53 antibodies (s-p53Abs) combined with carcinoembryonic antigen (CEA) measurements during the follow-up of colorectal cancer (CRC) patients after curative resection.

METHODS

A highly specific enzyme-linked immunosorbent assay was used to analyze s-p53Abs levels in 305 CRC patients before and after curative resection at a single institution. Agreement between recurrence and serial s-p53Ab and CEA measurements was evaluated by diagnostic accuracy odds ratio (DOR), kappa, and area under receiver operating characteristic curve (AUC).

RESULTS

Among 305 patients, 76 (25%) patients had disease recurrence during follow-up. None of the 168 s-p53Ab seronegative patients (s-p53Ab < 10 U/microL) without recurrence had an abnormal s-p53Ab test during follow-up. Among the remaining low-level (10 U/microL <or= s-p53Ab <or= 76 U/microL, n = 103) and high-level (s-p53Ab titer > 76 U/microL, n = 34) seropositive patients, recurrence defined by s-p53Ab tests resulted in a DOR of 4.3 and infinity, a kappa of 0.35 and 1.00, and an AUC of 0.633 [95% confidence interval (CI), 0.495 to 0.772; P = 0.047], and 1.0 (95% CI, 1.000 to 1.000; P < 0.0001), respectively. Recurrence defined by CEA tests had an AUC of 0.781 (95% CI, 0.654 to 0.909) for low-level and 0.796 (95% CI, 0.611 to 0.982) for high-level seropositive patients.

CONCLUSIONS

Agreement between clinical recurrence and serial s-p53Ab test was dependent upon preoperative s-p53Ab level. Serial s-p53Ab testing outperformed CEA testing when predicting clinical recurrence in colorectal cancer patients with an abnormal preoperative s-p53Ab level.

Appropriateness of colonoscopy in a digestive endoscopy unit: a prospective study using ASGE guidelines

RATIONALE, AIMS AND OBJECTIVES

Appropriate indications for colonoscopy (C) are essential for a rational use of resources. The aim of this study is to evaluate the appropriateness of indication for C according to the American Society for Gastrointestinal Endoscopy (ASGE) guidelines and to evaluate whether appropriate use was correlated with the diagnostic yield of C.

METHODS

We analysed 677 consecutive C performed over an 11-month period in a digestive endoscopy unit with an open access system.

RESULTS

The rate of 'generally indicated' C was 77% and 'generally not indicated' C was 18%. The rate of indication not listed in the ASGE guidelines was 5%. The percentage of generally not indicated C requested by gastroenterologists for outpatients was lower than that requested by primary care surgeons or doctors (9.5%, 29%, 25.3%, respectively). In 38 (7.3%) and in 111 (21.3%) of 520 patients with appropriate C, cancer and polyps larger than 5 mm were found, respectively. Twenty polyps greater than 5 mm were detected in 15 cases (12%) of 122 inappropriate C, with only one case of intramucosal carcinoma; four (12%) polyps measuring over 5 mm were found in C not listed in ASGE guidelines. No advanced stage cancer was detected in the inappropriate group and in C not listed in ASGE guidelines.

CONCLUSIONS

Our results showed the high rate of inappropriate procedures, according to ASGE guidelines, requested by surgeons, internists and primary care doctors for both outpatients and inpatients. The proportion of not indicated endoscopic procedures requested by gastroenterologists must be reduced through more carefully application of ASGE guidelines. Endoscopic findings were more stringent in appropriate C.

Cost of care of colorectal cancers according to health care patterns and stage at diagnosis in France

Little is known about the economic burden associated with colorectal cancer in France. The aim of this study was to evaluate the effects of age, stage at diagnosis, health care pattern and level of comorbidities on the mean cost of the management of colorectal cancers, using data from a population-based registry and the French health care system. We estimated the direct costs of medical care for 384 colorectal cancers diagnosed in 2004, using the three main databases of the National Health Insurance. The cost of management was defined as the sum of all health expenditures over the 12 months following the date of diagnosis. The mean cost for first-year management was 24,966 euro (SE 1,195 euro). There was no significant difference in overall costs in relation to sex, age, Charlson index score, cancer location or health care pattern. Costs increased significantly with cancer extension from 17,596 euro for stage I to 35,059 euro for stage IV. Hospitalisation charges represented the greatest economic burden (55.2%), followed by medical purchases (24.4%), outpatient care (17.8%) and transportation (2.5%). These results confirm the major economic burden of colorectal cancer and indicate that total costs depend mainly on the stage at diagnosis. By improving stage at diagnosis, mass screening could contribute to decreasing the cost of managing colorectal cancers.

Negative serum carcinoembryonic antigen has insufficient accuracy for excluding recurrence from patients with Dukes C colorectal cancer: analysis with likelihood ratio and posttest probability in a follow-up study

PURPOSE

This study was designed to determine the efficacy of carcinoembryonic antigen (CEA) monitoring for screening patients with colorectal cancer by using posttest probability of recurrence.

METHODS

For this study, 348 (preoperative serum CEA level elevated: CEA+, n = 119; or normal: CEA-, n = 229) patients who had undergone potentially curative surgery for colorectal cancer were enrolled. After five-year follow-up with measurements of serum CEA levels and imaging workup, posttest probabilities of recurrence were calculated.

RESULTS

Recurrence was observed in 39 percent of CEA+ patients and 30 percent in CEA- patients, and CEA levels were elevated in 33.3 percent of CEA+ patients and 17.5 percent of CEA- patients. With obtained sensitivity (68.4 percent, CEA+; 41 percent, CEA-), specificity (83 percent, CEA+; 91 percent, CEA-) and likelihood ratio (test positive: 4.0, CEA+; 4.4, CEA-; and test negative: 0.38, CEA+; 0.66, CEA-), posttest probability given the presence of CEA elevation in the CEA+ and CEA- was 72.2 and 65.5 percent, respectively, and that given the absence of CEA elevation was 20 and 22.2 percent, respectively.

CONCLUSIONS

Whereas postoperative CEA elevation indicates recurrence with high probability, a normal postoperative CEA is not useful for excluding the probability of recurrence.

ASCO 2006 Update of Recommendations for the Use of Tumor Markers in Gastrointestinal Cancer

Purpose

To update the recommendations for the use of tumor marker tests in the prevention, screening, treatment, and surveillance of gastrointestinal cancers.

Methods

For the 2006 update, an update committee composed of members from the full Panel was formed to complete the review and analysis of data published since 1999. Computerized literature searches of Medline and the Cochrane Collaboration Library were performed. The Update Committee's literature review focused attention on available systematic reviews and meta-analyses of published tumor marker studies.

Recommendations and Conclusion

For colorectal cancer, it is recommended that carcinoembryonic antigen (CEA) be ordered preoperatively, if it would assist in staging and surgical planning. Postoperative CEA levels should be performed every 3 months for stage II and III disease for at least 3 years if the patient is a potential candidate for surgery or chemotherapy of metastatic disease. CEA is the marker of choice for monitoring the response of metastatic disease to systemic therapy. Data are insufficient to recommend the routine use of p53, ras, thymidine synthase, dihydropyrimidine dehydrogenase, thymidine phosphorylase, microsatellite instability, 18q loss of heterozygosity, or deleted in colon cancer (DCC) protein in the management of patients with colorectal cancer. For pancreatic cancer, CA 19-9 can be measured every 1 to 3 months for patients with locally advanced or metastatic disease receiving active therapy. Elevations in serial CA 19-9 determinations suggest progressive disease but confirmation with other studies should be sought. New markers and new evidence to support the use of the currently reviewed markers will be evaluated in future updates of these guidelines.