Cost-effectiveness modeling of colorectal cancer: Computed tomography colonography vs colonoscopy or fecal occult blood tests

A Comparison of International Modeling Methods for Evaluating Health Economics of Colorectal Cancer Screening: A Systematic Review

OBJECTIVES

Cost-effectiveness analysis (CEA) is an accepted approach to evaluate cancer screening programs. CEA estimates partially depend on modeling methods and assumptions used. Understanding common practice when modeling cancer relies on complete, accessible descriptions of prior work. This review's objective is to comprehensively examine published CEA modeling methods used to evaluate colorectal cancer (CRC) screening from an aspiring modeler's perspective. It compares existing models, highlighting the importance of precise modeling method descriptions and essential factors when modeling CRC progression.

METHODS

MEDLINE, EMBASE, Web of Science, and Scopus electronic databases were used. The Consolidated Health Economic Evaluation Reporting Standards statement and data items from previous systematic reviews formed a template to extract relevant data. Specific focus included model type, natural history, appropriate data sources, and survival analysis.

RESULTS

Seventy-eight studies, with 52 unique models were found. Twelve previously published models were reported in 39 studies, with 39 newly developed models. CRC progression from the onset was commonly modeled, with only 6 models not including it as a model component.

CONCLUSIONS

Modeling methods needed to simulate CRC progression depend on the natural history structure and research requirements. For aspiring modelers, accompanying models with clear overviews and extensive modeling assumption descriptions are beneficial. Open-source modeling would also allow model replicability and result in appropriate decisions suggested for CRC screening programs.

Recent diagnostic procedures for colorectal cancer screening: Are they cost-effective?

Colorectal cancer (CRC) is the third most common cancer worldwide and the fourth most common cause of death. Reduction in mortality rates in some countries worldwide are most likely ascribed to CRC screening and/or improved treatments. We reviewed the most relevant articles which discuss the cost-effectiveness of colorectal cancer screening procedures, in particular, the recent ones through the last eight years. The effectiveness of screening estimated by discounted life years gained (LYGs) compared to no screening, differed considerably between the studies. Despite these differences, all studies consistently emphasized that screening for CRC was cost-effective compared with no screening for each of the recognized screening strategies. Newer technologies for colorectal cancer screening, including computed tomographic colonography (CTC), faecal DNA test, and Pillcam Colon are less invasive and accurate, however, they are not cost-effective, as their cost was higher than all other established screening strategies. When compliance and adherence to such new techniques are increased more than the established strategies they would be more cost-effective particularly CTC.

Screening and Surveillance of Colorectal Cancer Using CT Colonography

OPINION STATEMENT

Colorectal cancer (CRC) is a common cancer among throughout the world with the highest rates in developed countries such as the USA. There is ample evidence demonstrating the beneficial effects of colorectal cancer screening and, largely thanks to screening initiatives and insurance coverage, epidemiologic analyses show a steady decline in both CRC incidence and mortality rates over the last several decades. However, screening rates for CRC in the US remain low and approximately 1 in 3 adults between the ages of 50 and 75 years has not undergone any form of CRC screening, highlighting the need for additional accurate, minimally invasive, and acceptable screening options. Computed tomography colonography (CTC) has emerged as a viable alternative to existing CRC screening tests and research continues to enhance our knowledge regarding the ability of CTC to play a meaningful role in optimizing CRC screening in areas where it is available. This review highlights recent publications of salient research in the field of CTC. CTC continues to evolve, with lower radiation doses and greater evidence of its ability to identify clinical relevant colonic and extracolonic abnormalities. Recent evidence has bolstered the currently recommended CTC screening interval of 5 years and has reiterated the cost-effectiveness of CTC as a CRC screening examination. Additionally, emerging evidence suggests a role for CTC as a polyp and CRC surveillance modality as well as a preoperative adjunct in patients with established CRC. Data supporting the safety and patient acceptance of CTC also has continued to accumulate and CTC has recently been endorsed as an appropriate test for CRC screening in multiple important guidelines and recommendations. CTC is poised to become an important option in the CRC screening and surveillance arena.

The role of virtual colonoscopy in colorectal screening

Colorectal cancer is the second leading cause of cancer-related deaths in the United States. The earlier colorectal cancer is detected, the better chance a person has of surviving 5 years after being diagnosed, emphasizing the need for effective and regular colorectal screening. Computed tomographic colonography has repeatedly demonstrated sensitivities equivalent to the current gold standard, optical colonoscopy, in the detection of clinically relevant polyps. It is an accurate, safe, affordable, available, reproducible, quick, and cost-effective option for colorectal screening and should be considered for mass screening.

An updated Asia Pacific Consensus Recommendations on colorectal cancer screening

OBJECTIVE

Since the publication of the first Asia Pacific Consensus on Colorectal Cancer (CRC) in 2008, there are substantial advancements in the science and experience of implementing CRC screening. The Asia Pacific Working Group aimed to provide an updated set of consensus recommendations.

DESIGN

Members from 14 Asian regions gathered to seek consensus using other national and international guidelines, and recent relevant literature published from 2008 to 2013. A modified Delphi process was adopted to develop the statements.

RESULTS

Age range for CRC screening is defined as 50-75 years. Advancing age, male, family history of CRC, smoking and obesity are confirmed risk factors for CRC and advanced neoplasia. A risk-stratified scoring system is recommended for selecting high-risk patients for colonoscopy. Quantitative faecal immunochemical test (FIT) instead of guaiac-based faecal occult blood test (gFOBT) is preferred for average-risk subjects. Ancillary methods in colonoscopy, with the exception of chromoendoscopy, have not proven to be superior to high-definition white light endoscopy in identifying adenoma. Quality of colonoscopy should be upheld and quality assurance programme should be in place to audit every aspects of CRC screening. Serrated adenoma is recognised as a risk for interval cancer. There is no consensus on the recruitment of trained endoscopy nurses for CRC screening.

CONCLUSIONS

Based on recent data on CRC screening, an updated list of recommendations on CRC screening is prepared. These consensus statements will further enhance the implementation of CRC screening in the Asia Pacific region.

An international review of the main cost-effectiveness drivers of virtual colonography versus conventional colonoscopy for colorectal cancer screening: is the tide changing due to adherence?

OBJECTIVES

The majority of recent cost-effectiveness reviews concluded that computerised tomographic colonography (CTC) is not a cost-effective colorectal cancer (CRC) screening strategy yet. The objective of this review is to examine cost-effectiveness of CTC versus optical colonoscopy (COL) for CRC screening and identify the main drivers influencing cost-effectiveness due to the emergence of new research.

METHODS

A systematic review was conducted for cost-effectiveness studies comparing CTC and COL as a screening tool and providing outcomes in life-years saved, published between January 2006 and November 2012.

RESULTS

Nine studies were included in the review. There was considerable heterogeneity in modelling complexity and methodology. Different model assumptions and inputs had large effects on resulting cost-effectiveness of CTC and COL. CTC was found to be dominant or cost-effective in three studies, assuming the most favourable scenario. COL was found to be not cost effective in one study.

CONCLUSIONS

CTC has the potential to be a cost-effective CRC screening strategy when compared to COL. The most important assumptions that influenced the cost-effectiveness of CTC and COL were related to CTC threshold-based reporting of polyps, CTC cost, CTC sensitivity for large polyps, natural history of adenoma transition to cancer, AAA parameters and importantly, adherence. There is a strong need for a differential consideration of patient adherence and compliance to CTC and COL. Recent research shows that laxative-free CTC screening has the potential to become a good alternative screening method for CRC as it can improve patient uptake of screening.

An evaluation of colonoscopy surveillance guidelines: are we actually adhering to the guidelines?

BACKGROUND

National guidelines put forth by the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Gastroenterology provide recommendations regarding colorectal cancer screening and follow-up surveillance. Practice patterns may differ from these guidelines. This study analyzes the concordance between a tertiary equal access system and national guidelines for colorectal cancer and polyp surveillance.

METHODS

We performed a retrospective database review of all patients at a single institution undergoing screening colonoscopy from 2010 to 2011. Patient demographics, indication for colonoscopy, pathologic findings, and follow-up recommendations documented by the provider were analyzed. Multivariate analysis was performed in an attempt to identify predictors of discordant recommendations.

RESULTS

One thousand four hundred twenty patients were identified (mean age, 54.3 ± 7.7 years, 48.6% women). The gastroenterology service performed the majority of colonoscopies (87.2%) compared with the surgery service (11.6%). The major indications were routine screening (84.4%) and a strong family history of colorectal cancer (12.2%). The adenoma detection rate for the entire cohort was 27.4%. Other pathologic conditions identified included hyperplastic polyps (16%), lymphoid aggregates (3.5%), and invasive adenocarcinoma (0.1%). Overall, follow-up recommendations correlated with established guidelines in 97% of cases. By multivariate analysis, only the final pathologic finding of lymphoid aggregates was associated with discordant recommendations (odds ratio [OR], 4.62; 95% confidence interval [CI], 1.64 to 12.99; P = .004). When comparing discordant recommendations between specialties, there was a statistically significant difference between gastroenterology (1.6%) and surgery (7.6%) (P < .0001) providers; surgeons trended toward recommending earlier follow-up examinations (P = .37).

CONCLUSIONS

Overall, surveillance recommendations correlated well with current national guidelines. Concordance rates were higher with gastroenterologists in this cohort. Alterations based on final pathologic examination and individual cases remain clinically important.