Abstract Cancer is the leading cause of death at ages ≤80 in the US. To understand the burden of cancer death potentially addressable by new or improved screening approaches, we estimated the proportion of US cancer deaths without recommended guideline-based screening, especially after accounting for lung cancer screening eligibility and adherence. Using 2018-2019 mortality data from the National Center for Health Statistics and published estimates of the proportion of screening-eligible lung cancer patients, we estimated that 31.4% of nearly 600,000 annual cancer deaths were from colorectal, female breast, cervical, and smoking-eligible lung cancers (Table). Further accounting for adherence to lung cancer screening guidelines reduced the estimated proportion of screened cancer deaths to 17.4%; thus, 82.6% of cancer deaths may not be addressed by current guideline-based screening. Among the cancers not covered by guideline-based screening are uncommon cancer types, which (as defined by the National Cancer Institute) comprised 30.4% of cancer deaths. According to incidence-based mortality data from Surveillance, Epidemiology, and End Results registries, 24.7% of all cancer deaths were from stage 4 cancer types without guideline-based screening. These estimates, based on population data without patient-level information on mode of diagnosis, almost certainly underestimate the percentage of cancer deaths missed by currently available screening efforts. The large proportion of cancer deaths unaddressed by guideline-based screening represents a vast opportunity for new cancer screening technologies that are safe, effective, accessible, and affordable to enable earlier detection and successful treatment of the full spectrum of cancer types that contribute to the overall cancer burden. Table. Deaths from cancer by primary type in 2018-2019, US National Center for Health Statistics, with eligibility for and adherence to guideline-based low-dose computed tomography screening for lung cancer All cancer types Lung Colon/rectum Breast (female) Uterine cervix Total screened % of all All cancer deaths 1,198,854 281,681 104,059 84,745 8,290 478,775 39.9% Eligible for screening based on smoking (63.7% of lung)* 179,431 104,059 84,745 8,290 376,525 31.4% Adherent to smoking-guideline-based screening (6.6% of lung)† 11,842 104,059 84,745 8,290 208,936 17.4% *Modeled estimate of proportion of lung cancer patients eligible for screening (Landy et al. 2023). †Lung cancer screening receipt from 2019 American College of Radiology Lung Cancer Screening Registry (Fedewa et al. 2022). Citation Format: Ellen T. Chang, Anuraag Kansal, Earl A. Hubbell, Graham A. Colditz, Allison W. Kurian, Christina A. Clarke. Most cancer deaths are unaddressed by current screening paradigms [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6075.