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The integration of molecular, genomic and epigenetic biomarkers into oncological diagnostics represents a paradigm shift in precision medicine, fundamentally transforming tumour classification and management. However, global adoption of molecular biomarkers remains profoundly asymmetric. Populations in low- and middle-income countries (LMICs) experience substantial deficits in access to even foundational diagnostic services. Given that LMICs are projected to account for nearly 80% of the estimated 21.6 million annual cancer cases by 2030, the imperative for the WHO to ensure its tumour classification systems promote health equity rather than inadvertently perpetuate existing disparities has never been more urgent.1In a recent editorial, Deshpande and colleagues appropriately highlight the significant under-representation of LMIC expertise in the sixth-edition WHO Blue Book classification panels, where LMIC specialists comprised merely 5% of contributing authors.2 3 They express valid concerns regarding the potential marginalisation of pathologists in resource-constrained environments through increasingly applied molecular-centric diagnostic frameworks. We concur that prevailing global pathology workforce imbalances, wherein LMICs frequently report fewer than one pathologist per 100 000 population compared with 5–10 per 100 000 in high-income settings, significantly compound these challenges. Furthermore, the increased use of ‘not otherwise specified’ diagnostic categories serves as a critical indicator of systemic infrastructure gaps rather than professional or diagnostic deficiencies. Currently, clinicians in LMICs are often compelled to outsource testing overseas if the patient can afford the cost, raising serious concerns regarding data governance and the security of sensitive patient information. Nevertheless, while the diagnosis of inequality is accurate, the proposed remedy warrants careful scrutiny. Deshpande and colleagues suggest a dual-tier diagnostic system featuring a morphology and basic immunohistochemistry-based ‘provisional diagnosis’ for resource-limited contexts, with molecular refinements relegated to supplementary appendices. We respectfully submit that this approach may paradoxically risk institutionalising inequality rather than ameliorating it.This tiered approach brings forth substantive ethical and pragmatic concerns. First, such stratification potentially goes against the WHO foundational principle of ensuring the highest attainable and equitable standard of health for all populations, effectively establishing a restrictive diagnostic ceiling that could become entrenched in LMIC healthcare systems. Second, we disagree with the proposal to place sophisticated tests in appendices unless they meet strict thresholds of global feasibility, therapeutic impact and affordability. Feasibility is dynamic and technology costs can drop rapidly, and requiring proven therapeutic impact before inclusion stifles the data collection needed to demonstrate utility in diverse populations. Affordability should not dictate clinical implementation; relegating molecular criteria to appendices signals they are secondary, discouraging investment needed to make them accessible. Third, this model risks systematically excluding LMIC patients from molecularly informed clinical trials, epidemiological research and access to emerging targeted therapies. Characterising molecular diagnostics as technologically unavailable in resource-limited settings fails to recognise substantial recent progress in technology accessibility and cost reduction. This trajectory is substantiated by evidence of feasibility as India’s Cancer Genome Atlas initiative successfully demonstrated approximately 60% next-generation sequencing coverage in urban centres, while the US National Cancer Institute’s Affordable Cancer Technologies Programme has piloted cost-effective molecular platforms across multiple sites in Africa and Asia.4–6 Emerging point-of-care innovations, including Clustered regularly Interspaced Short Palindromic repeats-based assays, as well as artificial intelligence-augmented diagnostic tools, demonstrate concordance with conventional methodologies while offering dramatically improved affordability and decentralisation potential.7 Technology alone is not enough; a systems-thinking approach is required. Without sustainable financing, workforce training and infrastructure, new tools cannot be used effectively. Public-private partnerships and pooled procurement models are essential to lower costs and ensure long-term sustainability. In Asia, leveraging existing regional mechanisms to prioritise medical devices and assay reagents while adapting to country-specific contexts could offer a promising pathway toward sustainable and equitable access to advanced diagnostic assays. Accelerated diagnostic pathways can significantly improve timeliness of treatment, proving that faster access is feasible without compromising quality.8Rather than stratifying scientific standards, we propose that the WHO maintain a unified, molecular-integrated classification system complemented by judicious and phased implementation. Crucially, this distinguishes between the diagnostic standard (which should be unified and optimal for all) and the implementation pathway (which may vary based on resources). For example, a laboratory might start with morphology and basic immunohistochemistry, progress to targeted molecular panels and eventually adopt comprehensive genomic profiling as capacity grows. Molecular criteria should remain integral to core diagnostic definitions while being accompanied by transparent, evidence-based guidance regarding practical adoption strategies tailored to diverse resource contexts.2To achieve this, future work must focus on capacity building rather than relaxed standards. The WHO should prioritise collaborative, country-led audits of diagnostic capacity in LMICs as a core element of global cancer control. These audits must evaluate the entire diagnostic pathway, from specimen handling and pathology workflows to molecular testing, quality assurance and turnaround times, and be co-designed with national pathology societies and major laboratories. In parallel, the WHO should invest in the co-development of context-appropriate molecular diagnostics rather than promoting the adoption of high-cost molecular platforms optimised and validated for high-income settings. Scalable technologies, technology transfer including open-source platforms, regional audit hubs, South-South knowledge exchange and local capacity building are essential for sustainability.Critically, governance mechanisms must ensure substantive LMIC leadership through equitable participation structures. LMIC representatives should have voting rights on classification panels, and major chapters should require mandatory LMIC co-chairs. The WHO Classification of Tumours must function as globally actionable frameworks, incorporating flexible implementation pathways and contextual guidance to serve every laboratory from Dhaka to Dublin through inclusion, innovation and shared accountability. Ultimately, health equity requires the construction of sustainable capacity. Blue Books should include implementation guidance updated as technologies become affordable, rather than relegating molecular advances to appendices that risk becoming an afterthought in LMICs. Ethical safeguards, including community involvement and data governance, must be central to implementation to protect patient rights.We call on the WHO to establish a Task Force on Equitable Diagnostic Implementation to oversee this transition. This body should report to the World Health Assembly, ensuring accountability against the NCD Global Action Plan 2013–2030.1 Our joint authorship from Singapore Health Services and the National Cancer Institute Sri Lanka exemplifies the cross-regional engagement required: by combining high-income infrastructure insights with LMIC clinical perspectives, we demonstrate that unified standards are achievable without compromising equity. Through inclusive development processes and shared accountability frameworks, WHO tumour classifications can effectively serve all laboratories, ensuring that molecular diagnostics transition from privileged access to a universal standard of care.