Trends in the hidden burden of cancer in an autopsy-based study over 66 years in Japan

Conventional cancer statistics account only for indiviuals with a clinical diagnosis, overlooking potentially large numbers of undetected malignant neoplasms. Autopsy-based studies offer a unique opportunity to estimate the burden of cancer, including latent tumors. In a cohort study of 1 486 557 hospital-based autopsies performed between 1958 and 2023 in Japan, 36 133 latent cancers were found. Detection rates increased over time, with latent prostate and thyroid cancers 6.9-fold and 60-fold more frequent than clinical cases; metastatic latent cancers made up 7.3% of cases and increased in number. The authors conclude that these findings suggest that a reservoir of undiagnosed, metastasis-competent cancers may increase with increasing longevity, and underscore the value of autopsy for cancer epidemiology.