GLOBOCAN 2022 Cancer Incidence in Populations Affected by Crises: A Global Mapping and Analysis
 
Background: Crises such as conflict, natural disasters, disease outbreaks, and humanitarian emergencies disrupt health systems, limit access to care, and exacerbate health inequities. Well-studied crises - including the COVID-19 pandemic - show how rapidly cancer diagnosis, treatment, and continuity of care can be compromised, leading to delayed diagnosis and likely worsen outcomes for cancer patients. Yet most existing evidence is fragmented, crisis-specific, with no comprehensive analysis across multiple types of crises.

Objectives: This study provides the first global mapping of cancer incidence in populations affected by crises, identifying where and to what extent different types of crises overlap with cancer burden for the year 2022.
 
Methods: We conducted a global cross-sectional analysis harmonising country-level national cancer incidence estimates from GLOBOCAN 2022 (ICD-10 C00–C97) with the INFORM Severity Index 2022, which measures severity of humanitarian crises on a scale from very low (1) to very high (5). Countries were categorised by crisis type (no crisis, single, multiple, or complex). To estimate the crisis-specific cancer burden, we applied the INFORM indicator percentage of people affected on the total population exposed as a weighting factor to the total estimated cancer cases per country. Beyond the overall index, we disaggregated crisis severity by the index dimensions “Conditions of People Affected” and “Complexity of Crisis”. A Spearman’s rank correlation was used to assess the relationship between crisis severity and age-standardised incidence rates (ASIR).
 
Results: Of the 184 countries analysed, 83 (45.1%) faced at least one crisis in 2022, with the highest prevalence in Africa (68.5% of countries). Globally, an estimated 1.57 million people (8.45%) – one in every 12 cancer patients – lived under crisis conditions. While Asia showed the highest absolute number of crisis-affected cancer cases (n=637,821), Africa faced the highest internal proportional burden, with 30.5% of its cancer population affected. The very-high-severity tier accounted for 60% of all crisis-affected cases despite representing the smallest total cancer populations. Female breast cancer remained the most frequent site among crisis countries, while cervical cancer rose to the third most common site in complex crisis settings. Finally, a significant moderate negative correlation was observed between crisis severity and reported ASIR (ρ = -0.45, p<.001).
 
Conclusions: This study provides the first systematic attempt to globally map the overlap between crisis conditions and cancer burden. Our findings indicate that cancer is a substantial and growing part of the global crises burden, especially in lower-HDI countries. Yet cancer care remains largely unrecognized in current humanitarian aid frameworks. Cancer care should no longer be viewed as an issue separate from crisis and emergency response but must be integrated into humanitarian planning and resource allocation. Strengthening health system resilience in high-burden countries is essential to ensure that cancer patients are not neglected during crises.

Global cancer population under crisis by INFORM severity index in 2022.