Highlights
A comprehensive analysis of over 1 million patients diagnosed with cancer during the first two years of the COVID-19 pandemic reveals a troubling shift in oncology outcomes. Key findings include:
- Significant absolute reductions in 1-year cause-specific survival (CSS) for both early-stage and late-stage cancer diagnoses in 2020 and 2021.
- An estimated 17,390 excess cancer-related deaths occurred within one year of diagnosis—a 13.1% increase over expected mortality based on prepandemic trends.
- The most pronounced survival drops were observed in elderly populations (aged 65+) and individuals of minoritized racial and ethnic backgrounds.
- Site-specific analyses highlighted substantial survival declines in early-stage esophageal and colorectal cancers, as well as late-stage prostate cancer.
Background: The Pandemic’s Shadow on Oncology
The COVID-19 pandemic necessitated a radical reorganization of healthcare systems worldwide. In the United States, this transition led to the widespread postponement of elective procedures, the suspension of routine cancer screenings, and a significant shift in patient behavior due to fear of infection. While previous research has documented the resulting delays in cancer diagnoses and the subsequent ‘stage migration’ toward more advanced disease, the direct impact of these disruptions on short-term survival remained largely unquantified until now.
Cancer survival is often a reflection of timely intervention—not just in terms of diagnosis, but also the continuity of surgical, radiological, and systemic therapies. When the pandemic strained hospital resources and interrupted treatment protocols, the clinical community anticipated a ‘tail’ of increased mortality. This study provides the empirical evidence needed to understand the magnitude of that impact during the first 24 months of the crisis.
Study Design and Methodology
This population-based cohort study utilized data from the Surveillance, Epidemiology, and End Results 21 Registries (SEER-21) database, which covers approximately 37% of the U.S. population. The researchers analyzed survival outcomes for individuals diagnosed with invasive cancer between January 1, 2015, and December 31, 2021.
The study cohort was divided into two groups: those diagnosed during the prepandemic period (2015–2019) and those diagnosed during the pandemic years (2020 and 2021). The primary endpoint was 1-year cause-specific survival (CSS), stratified by the stage at diagnosis. By comparing the observed survival in 2020 and 2021 against the established trends from the preceding five years, the authors were able to estimate absolute survival reductions and calculate the number of excess deaths attributable to pandemic-era disruptions.
Key Findings: A Quantifiable Decline in Survival
The study included a total of 1,008,012 individuals diagnosed with cancer during the pandemic’s first two years (473,781 in 2020 and 534,231 in 2021). The demographic breakdown was relatively consistent across both years, with approximately 51% of patients aged 65 or older and a diverse racial composition including White (63-64%), Hispanic (15-16%), and Black (11.5-11.7%) individuals.
Stage-Specific Survival Reductions
The data demonstrated that the decline in survival was not confined to those with advanced disease. For early-stage diagnoses, absolute reductions in 1-year CSS were -0.44 percentage points (95% CI, -0.54 to -0.34) in 2020 and -0.27 percentage points (95% CI, -0.37 to -0.16) in 2021. Late-stage diagnoses saw even steeper declines: -1.34 percentage points (95% CI, -1.75 to -0.93) in 2020 and -1.20 percentage points (95% CI, -1.69 to -0.71) in 2021.
The Human Cost: 17,390 Excess Deaths
Perhaps the most striking finding is the cumulative mortality impact. The study estimates that survival reductions resulted in 17,390 more cancer-related deaths within the first year of diagnosis than would have been expected. This represents a 13.1% increase in mortality, highlighting the severe consequences of care interruptions, regardless of the patient’s initial cancer stage.
Demographic and Site-Specific Vulnerabilities
The impact was not felt equally across all groups. Absolute survival reductions exceeding 1.00 percentage point were consistently observed in both 2020 and 2021 for late-stage diagnoses among patients aged 65 and older and those identified as American Indian, Alaska Native, Asian, or Pacific Islander. These findings suggest that the pandemic may have exacerbated existing healthcare disparities.
Site-specific data revealed that certain cancers were particularly sensitive to pandemic disruptions. For early-stage esophageal cancer, survival dropped by -3.89 and -3.67 percentage points in 2020 and 2021, respectively. Early-stage colorectal cancer and late-stage prostate cancer also showed significant survival deficits, likely reflecting the high dependency of these conditions on timely surgical intervention and routine monitoring.
Expert Commentary: Interpreting the Disruption
The findings from Burus et al. underscore a critical lesson for healthcare policy: the ‘collateral damage’ of a public health crisis can be as lethal as the crisis itself. The fact that survival declined even when controlled for the stage at diagnosis suggests that the issue was not merely ‘late detection,’ but rather a failure in the continuity of care post-diagnosis.
Mechanistic Insights
The biological plausibility of these findings rests on the ‘time-to-treatment’ (TTT) metric. In oncology, even minor delays in the initiation of adjuvant chemotherapy or definitive surgery can allow for micro-metastatic progression. During 2020 and 2021, many patients faced delayed surgeries due to ICU bed shortages or postponed systemic therapies to avoid immunosuppression during viral surges. Furthermore, the reduction in 1-year CSS for early-stage colorectal and esophageal cancers—diseases where surgical margins and lymph node yields are critical—points toward potential variations in surgical quality or post-operative care during the pandemic peaks.
Study Strengths and Limitations
A major strength of this study is its use of the SEER-21 database, which provides a high-quality, population-based view of the U.S. cancer landscape. However, there are limitations. The data does not explicitly detail the exact cause of care disruption for each individual (e.g., whether it was a hospital policy, a patient’s fear of COVID-19, or a direct COVID-19 infection). Additionally, cause-specific survival focuses on cancer deaths, but the interplay between COVID-19 morbidity and cancer progression remains a complex variable that may influence these outcomes.
Conclusion: Implications for Future Healthcare Resilience
This cohort study confirms that the COVID-19 pandemic significantly impaired short-term survival for cancer patients diagnosed in 2020 and 2021. The loss of over 17,000 lives beyond expected levels serves as a stark reminder of the necessity of maintaining oncological services during future emergencies. Moving forward, health systems must prioritize the development of ‘resilient’ cancer pathways—utilizing telehealth, decentralized clinical trials, and protected ‘cold sites’ for surgery—to ensure that life-saving cancer care is never again sidelined by a concurrent public health crisis.
References
Burus T, Damgacioglu H, Huang B, Tucker TC, Deshmukh AA, Lang Kuhs KA. Survival of Patients Diagnosed With Cancer During the COVID-19 Pandemic. JAMA Oncol. 2026 Feb 5:e256332. doi: 10.1001/jamaoncol.2025.6332. Epub ahead of print. PMID: 41642595; PMCID: PMC12878639.