Systematic reviews as a "lens of evidence": Determinants of cost-effectiveness of breast cancer screening

A critical review and analysis of the context, current burden, and application of policy to improve cancer equity in Ghana

BACKGROUND

Cancer causes a major disease burden worldwide. This is increasingly being realised in low and middle-income countries, which account disproportionately for preventable cancer deaths. Despite the World Health Organization calling for governments to develop policies to address this and alleviate cancer inequality, numerous challenges in executing effective cancer policies remain, which require consideration of the country-specific context. As this has not yet been considered in Ghana, the aim of this review was to bring together and critique the social-environmental, health policy and system factors to identifying opportunities for future health policies to reduce cancer burden in the Ghanian context. A critical policy-focused review was conducted to bring together and critique the current health systems context relating to cancer in Ghana, considering the unmet policy need, health system and social factors contributing to the burden and policy advances related to cancer.

CONCLUSION

The findings highlight the changing burden of cancer in Ghana and the contextual factors within the socio-ecosystem that contribute to this. Policies around expanding access to and coverage of services, as well as the harmonization with medical pluralism have potential to improve outcomes and increase equity but their implementation and robust data to monitor their impact pose significant barriers.

Healthcare and Cancer Treatment Costs of Breast Screening Outcomes among Higher than Average Risk Women

Concurrent cohorts of 644,932 women aged 50-74 screened annually due to family history, dense breasts or biennially in the Ontario Breast Screening Program (OBSP) from 2011-2014 were linked to provincial administrative datasets to determine health system resource utilization and costs. Age-adjusted mean and median total healthcare costs (2018 CAD) and incremental cost differences were calculated by screening outcome and compared by recommendation using regression models. Healthcare costs were compared overall and 1 year after a false positive (n = 46,081) screening mammogram and 2 years after a breast cancer diagnosis (n = 6011). Mean overall healthcare costs by age were highest for those 60-74, particularly with annual screening for family/personal history (CAD 5425; 95% CI: 5308 to 5557) compared to biennial. Although the mean incremental cost difference was higher (23.4%) by CAD 10,235 (95% CI: 6141 to 14,329) per breast cancer for women screened annually for density ≥ 75% compared to biennially, the cost difference was 12.0% lower (-CAD 461; 95% CI: -777 to -114) per false positive result. In contrast, for women screened annually for family/personal history, the mean cost difference per false positive was 19.7% higher than for biennially (CAD 758; 95% CI: 404 to 1118); however, the cost difference per breast cancer was only slightly higher (2.5%) by CAD 1093 (95% CI: -1337 to CAD 3760). Understanding that associated costs of annual compared to biennial screening may balance out by age and outcome can assist decision-making regarding the use of limited healthcare resources.

Critical Appraisal of Decision Models Used for the Economic Evaluation of Bladder Cancer Screening and Diagnosis: A Systematic Review

BACKGROUND AND OBJECTIVE

Bladder cancer is common among current and former smokers. High bladder cancer mortality may be decreased through early diagnosis and screening. The aim of this study was to appraise decision models used for the economic evaluation of bladder cancer screening and diagnosis, and to summarise the main outcomes of these models.

METHODS

MEDLINE via PubMed, Embase, EconLit and Web of Science databases was systematically searched from January 2006 to May 2022 for modelling studies that assessed the cost effectiveness of bladder cancer screening and diagnostic interventions. Articles were appraised according to Patient, Intervention, Comparator and Outcome (PICO) characteristics, modelling methods, model structures and data sources. The quality of the studies was also appraised using the Philips checklist by two independent reviewers.

RESULTS

Searches identified 3082 potentially relevant studies, which resulted in 18 articles that met our inclusion criteria. Four of these articles were on bladder cancer screening, and the remaining 14 were diagnostic or surveillance interventions. Two of the four screening models were individual-level simulations. All screening models (n = 4, with three on a high-risk population and one on a general population) concluded that screening is either cost saving or cost effective with cost-effectiveness ratios lower than $53,000/life-years saved. Disease prevalence was a strong determinant of cost effectiveness. Diagnostic models (n = 14) assessed multiple interventions; white light cystoscopy was the most common intervention and was considered cost effective in all studies (n = 4). Screening models relied largely on published evidence generalised from other countries and did not report the validation of their predictions to external data. Almost all diagnostic models (n = 13 out of 14) had a time horizon of 5 years or less and most of the models (n = 11) did not incorporate health-related utilities. In both screening and diagnostic models, epidemiological inputs were based on expert elicitation, assumptions or international evidence of uncertain generalisability. In modelling disease, seven models did not use a standard classification system to define cancer states, others used risk-based, numerical or a Tumour, Node, Metastasis classification. Despite including certain components of disease onset or progression, no models included a complete and coherent model of the natural history of bladder cancer (i.e. simulating the progression of asymptomatic primary bladder cancer from cancer onset, i.e. in the absence of treatment).

CONCLUSIONS

The variation in natural history model structures and the lack of data for model parameterisation suggest that research in bladder cancer early detection and screening is at an early stage of development. Appropriate characterisation and analysis of uncertainty in bladder cancer models should be considered a priority.

An artificial intelligence based app for skin cancer detection evaluated in a population based setting

Artificial intelligence (AI) based algorithms for classification of suspicious skin lesions have been implemented in mobile phone apps (mHealth), but their effect on healthcare systems is undocumented. In 2019, a large Dutch health insurance company offered 2.2 million adults free access to an mHealth app for skin cancer detection. To study the impact on dermatological healthcare consumption, we conducted a retrospective population-based pragmatic study. We matched 18,960 mHealth-users who completed at least one successful assessment with the app to 56,880 controls who did not use the app and calculated odds ratios (OR) to compare dermatological claims between both groups in the first year after granting free access. A short-term cost-effectiveness analysis was performed to determine the cost per additional detected (pre)malignancy. Here we report that mHealth-users had more claims for (pre)malignant skin lesions than controls (6.0% vs 4.6%, OR 1.3 (95% CI 1.2-1.4)) and also a more than threefold higher risk of claims for benign skin tumors and nevi (5.9% vs 1.7%, OR 3.7 (95% CI 3.4-4.1)). The costs of detecting one additional (pre)malignant skin lesion with the app compared to the current standard of care were €2567. Based on these results, AI in mHealth appears to have a positive impact on detecting more cutaneous (pre)malignancies, but this should be balanced against the for now stronger increase in care consumption for benign skin tumors and nevi.

Perspective on oral cancer screening: Time for implementation research and beyond

Screening aims to detect cancer in asymptomatic populations. In oral cancer, clinical oral examination is the current standard method for screening. Oral cancer screening may be performed by a physician or a healthcare workers and is an affordable and feasible method. There is some evidence that this low-cost method is effective in decreasing mortality from oral cancer in high risk population. The cluster-randomised trial in India that had 15 years of follow-up reported an 81 % mortality reduction in high-risk populations of tobacco and/or alcohol users who adhered to four screening rounds. The observational studies similarly reported 21-22 % reduction in advanced oral cancer and 24-26 % reduction in oral cancer mortality among high risk population. Implementation and evaluation of oral cancer screening programmes in high risk population will support the goals of the World Health Organisation on global oral health.

Cost-effectiveness of clinical breast examination screening programme among HER2-positive breast cancer patients: a modelling study

PURPOSE

For many low- and middle-income countries (LMICs), breast cancer (BC) screening based on mammography is not a viable option. Clinical breast examination (CBE) may represent a pragmatic and cost-effective alternative. This paper examines the cost-effectiveness of CBE screening programme among a patient group for whom its cost-effectiveness is likely to be least evident (HER2-positive patients) and discuss the wider implications for BC screening in LMICs.

METHODS

A Markov model was used to examine clinical and economic outcomes over a life-time horizon from the patient, public payer, and healthcare sector perspective. HER2-positive patients entered the model at either disease-free survival or metastatic BC state. The downstaging effect of CBE determined the starting probabilities in the no-screening and screening scenarios. The model used a monthly cycle length, with half-cycle correction. Costs and outcomes were discounted at 1.5% annually.

RESULTS

Compared with no-screening, the cost-effectiveness ratio (ICER) per quality-adjusted life-year gained for the CBE screening programme was $1801, $2381, and $4179 from three mentioned perspectives, respectively. The finding of cost-effectiveness remained robust to a range of sensitivity analyses. The parameters to which ICERs are most sensitive are average age of cohorts, reduction in proportion of metastatic patients at diagnosis, cost of CBE, and BC detection rate of the programme.

CONCLUSION

For HER2-positive patients and compared with no-screening, CBE screening programme in Vietnam is cost-effective from all investigated perspectives. CBE is a 'good value' intervention and should be considered for implementation throughout Vietnam as well as in LMICs where mammography is not feasible.

Economic evaluations of mammography to screen for breast cancer in low- and middle-income countries: A systematic review

Background

Low- and middle-income countries (LMICs) have limited resources compared to high-income countries (HICs). Therefore, it is critical that LMICs implement cost-effective strategies to reduce the burden of breast cancer. This study aimed to answer the question of whether mammography is a cost-effective breast cancer screening method in LMICs.

Methods

A systematic article search was conducted through Medline, Embase, Web of Science, and Econlit. Studies were included only if they conducted a full economic evaluation and focused on mammography screening in LMICs. Two reviewers screened through the title and abstract of each article and continued with full-text selection. Data were extracted and synthesized narratively. Quality assessment for each included study was conducted using the Consensus Health Economic Criteria (CHEC) extended checklist.

Results

This review identified 21 studies economically evaluating mammography as a breast cancer screening method in LMICs. Eighteen of these studies concluded that mammography screening was a cost-effective strategy. Most studies (71%) were conducted in upper-middle-income countries (Upper MICs). The quality of the studies varied from low to good. Important factors determining cost-effectiveness are the target age group (eg, 50-59 years), the screening interval (eg, biennial or triennial), as well as any combination with other breast cancer control strategies (eg, combination with treatment strategy for breast cancer patients).

Conclusions

Mammography screening appeared to be a cost-effective strategy in LMICs, particularly in Upper MICs. More studies conducted in lower-middle-income and low-income countries are needed to better understand the cost-effectiveness of mammography screening in these regions.

Cost-effectiveness evaluation of mammography screening program in Taiwan: Adjusting different distributions of age and calendar year for real world data

BACKGROUND/PURPOSE

We estimated loss-of-life expectancy (LE) and lifetime medical expenditures (LME) stratified by stages to evaluate the cost-effectiveness of breast cancer (BC) screening in Taiwan.

METHODS

We interlinked four national databases- Cancer Registry, Mortality Registry, National Health Insurance Claim, and Mammography Screening. A cohort of 123,221 BC was identified during 2002-2015 and followed until December 31, 2017. We estimated LE and loss-of-LE by rolling extrapolation algorithm using age-, sex-, and calendar-year-matched referents simulated from vital statistics. LME was estimated by multiplying monthly cost with survival probability and adjusted for annual discount rate. We calculated incremental cost-effectiveness ratio (ICER) by comparing the loss-of-LE of those detected by screening versus non-screening after accounting for administration fees and radiation-related excess BC.

RESULTS

The LEs of stages I, II, III, and IV were 31.4, 27.2, 20.0, and 5.2 years, respectively, while the loss-of-LEs were 1.2, 4.9, 11.7, and 25.0 years with corresponding LMEs of US$ 73,791, 79,496, 89,962, and 66,981, respectively. The difference in LE between stages I and IV was 26.2 years while that of loss-of-LE was 23.8 years, which implies that a potential lead time bias may exist if diagnosis at younger ages for earlier stages were not adjusted for. The ICER of mammography seemed cost-saving after the coverage exceeded half a million.

CONCLUSION

Mammography could detect BC early and be cost-saving after adjustment for different distributions of age and calendar year of diagnosis. Future studies exploring healthcare expenditure and impaired quality of life for false-positive cases are warranted.

Systematic reviews as a "lens of evidence": Determinants of participation in breast cancer screening

OBJECTIVE

To assess the determinants of the participation rate in breast cancer screening programs by conducting a systematic review of reviews.

METHODS

We conducted a systematic search in PubMed via Medline, Scopus, Embase, and Cochrane identifying the literature up to April 2019. Out of 2258 revealed unique abstracts, we included 31 reviews, from which 25 were considered as systematic. We applied the Walsh & McPhee Systems Model of Clinical Preventive Care to systematize the determinants of screening participation.

RESULTS

The reviews, mainly in high-income settings, reported a wide range for breast cancer screening participation rate: 16-90%. The determinants of breast cancer screening participation were simple low-cost interventions such as invitation letters, basic information on screening, multiple reminders, fixed appointments, prompts from healthcare professionals, and healthcare organizational factors (e.g. close proximity to screening facility). More complex interventions (such as face-to-face counselling or home visits), mass media or improved access to transport should not be encouraged by policy makers unless other information appears. The repeated participation in mammography screening was consistently high, above 62%. Previous positive experience with screening influenced the repeated participation in screening programs. The reviews were inconsistent in the use of terminology related to breast cancer screening participation, which may have contributed to the heterogeneity in the reported outcomes.

CONCLUSIONS

This study shows that consistent findings of systematic reviews bring more certainty into the conclusions on the effects of simple invitation techniques, fixed appointments and prompts, as well as healthcare organizational factors on promoting participation rate in screening mammography.

Network Meta-analysis for the Diagnostic Approach to Pathologic Nipple Discharge

Pathologic nipple discharge (PND) is one of the most common breast-related complaints for referral because of its supposed association with breast cancer. The aim of this network meta-analysis (NMA) was to compare the diagnostic efficacy of ultrasound, mammogram, cytology, magnetic resonance imaging (MRI), and ductoscopy in patients with PND, as well as to determine the best diagnostic strategy to assess the risk of malignancy as cause for PND. Cochrane Library, PubMed, and Embase were searched to collect relevant literature from the inception of each of the diagnostic methods until January 27, 2020. The search yielded 1472 original citations, of which 36 studies with 3764 patients were finally included for analysis. Direct and indirect comparisons were performed using an NMA approach to evaluate the combined odd ratios and to determine the surface under the cumulative ranking curves (SUCRA) of the diagnostic value of different imaging methods for the detection of breast cancer in patients with PND. Additionally, a subgroup meta-analysis comparing ductoscopy to MRI when conventional imaging was negative was also performed. According to this NMA, sensitivity for detection of malignancy in patients with PND was highest for MRI (83%), followed by ductoscopy (58%), ultrasound (50%), cytology (38%), and mammogram (22%). Specificity was highest for mammogram (93%) followed by ductoscopy (92%), cytology (90%), MRI (76%), and ultrasound (69%). Diagnostic accuracy was the highest for ductoscopy (88%), followed by cytology (82%), MRI (77%), mammogram (76%), and ultrasound (65%). Subgroup meta-analysis (comparing ductoscopy to MRI when ultrasound and mammogram were negative) showed no significant difference in sensitivity, but ductoscopy was statistically significantly better with regard to specificity and diagnostic accuracy. The results from this NMA indicate that although ultrasound and mammogram may remain low-cost useful first choices for the detection of malignancy in patients with PND, ductoscopy outperforms most imaging techniques (especially MRI) and cytology.

Systematic reviews as a "lens of evidence": Determinants of cost-effectiveness of breast cancer screening

Systematic reviews with economic components are important decision tools for stakeholders seeking to evaluate technologies, such as breast cancer screening (BCS) programs. This overview of systematic reviews explores the determinants of the cost-effectiveness of BCS and assesses the quality of secondary evidence. The search identified 30 systematic reviews that reported on the determinants of the cost-effectiveness of BCS, including the costs of breast cancer and BCS. While the quality of the reviews varied widely, only four out of 30 papers were considered to be of a high quality. We did not identify publication bias in the original evidence on the cost-effectiveness of mammography screening; however, we highlight a need for improved clarity in both reporting and data verification. The reviews consisted mainly of studies from high-income countries. Breast cancer costs varied widely among the studies. Factors leading to higher costs included: time (diagnosis and last months before death), later stage or metastases, recurrence of the disease, age below 64 years and type of follow-up (more intensive or more specialized). Overall, screening with mammography was considered cost-effective in the age range 50-69 years in Western European and Northern American countries but not for older or younger women. Its cost-effectiveness was questionable for low-income settings and Asia. Mammography screening was more cost-effective with biennial screening compared to annual screening and single reading using computer-aided detection vs double reading. No information on the cost-effectiveness of ultrasonography was found, and there is much uncertainty on the cost-effectiveness of CBE because of methodological limitations.