ED Sciences de la Vie et de la Santé
Understanding cancer evolution: the role of comparative oncology
by Benjamin SPADA (Immunologie Conceptuelle, Expérimentale et Translationnelle)
The defense will take place at 14h00 - Amphithéâtre BBS Bâtiment Bordeaux Biologie Santé, 2 Rue Dr Hoffmann Martinot, 33076 Bordeaux Cedex
in front of the jury composed of
- Thomas PRADEU - Directeur de recherche - CNRS/Laboratoire Immunoconcept - Directeur de these
- Lucie LAPLANE - Chargée de recherche - CNRS - IHPST / Université Paris 1 Panthéon-Sorbonne - Rapporteur
- Samir OKASHA - Professor - University of Bristol - Rapporteur
- Marie L. KAISER - Full professor - Bieledfeld University - Examinateur
- Carlo MALEY - Professor - Arizona State University - Examinateur
This dissertation explores what the study of the organismal evolution of cancer can bring to cancer research. While most philosophical work has focused on tumour evolution within individuals, this thesis shifts the perspective to cancer across the tree of life. It shows that evolutionary biology provides a powerful framework not only to situate cancer historically but also to reconceptualize it as a biological phenomenon. Chapter I examines attempts to explore the different approaches of organismal evolution of cancer, especially the influential view of cancer as “cheating” in multicellularity. While this perspective highlights cancer's ubiquity, it lacks conceptual precision and leads to an overly broad definition. Chapter II traces the history of comparative oncology, from early descriptive studies to its recent “evolutionarization,” showing how the field is the best approach to organismal evolution of cancer. Chapter III presents the core contribution of this dissertation: a universal, evolution-based definition of cancer. By focusing on processes rather than outcomes, this definition avoids the anthropocentric bias commonly found in general oncology and allows for more robust cross-species comparisons. Chapter IV then builds on earlier critiques to propose avenues for comparative oncology, including sharpening definitions, aligning methods with goals, and clarifying the field's theoretical ambitions. The central claim defended here is that studying the organismal evolution of cancer enriches research not by adding complexity but by providing conceptual clarity and unity. This thesis contribution of this work is both academic and conceptual: clarifying what cancer is, mapping the field of comparative oncology, and suggesting how philosophy can help science ask to better formulate their questions. Ultimately, situating cancer in its evolutionary history shows it to be not only a human disease but also a fundamental biological process, one that philosophy is uniquely well equipped to clarify.