Primate Comparative Oncology Reveals Unique Human Cancer Susceptibility

Studying cancer from an evolutionary perspective can yield important theoretical and applied insights; however, little is known about the prevalence of cancer among non-human primates. Non-human primates are our closest living relatives, yet the primate lineage is phenotypically diverse, exhibiting wide variation in evolutionary and life-history characteristics. By integrating comparative phenotypic data with prevalence records of neoplastic disease, we assembled a dataset of 2,095 individuals from 36 species across nine primate families to examine cross-species cancer risk. Additionally, functional in vitro studies using isolated and cultured primary fibroblast cell lines from representative species show that resistance to cellular death correlates with certain life-history traits. Comparative phylogenetic modeling of human cancer risk, situated within the broader primate phylogeny, demonstrates a drastic reduction in cancer risk even among primates most closely related to humans (e.g., the great apes). Together, large-scale cancer prevalence records and functional assays provide valuable insights into the ecological and cellular dynamics of cancer in our closest living relatives—and in ourselves. Citation Format: Zachary Taylor Compton, Walker Mellon, Lisa M. Abegglen, Tara Harrison, Joshua D. Schiffman, Amy M. Boddy, Carlo C. Maley. Primate comparative oncology reveal humans' unique cancer susceptibility [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7639.