How are distinct explanations of cancer alternative to, articulated with, or enabled by one another in research towards precision immuno-oncology? To answer this question, this chapter draws on the qualitative study of a platform for the development of neoantigen-based adoptive cell transfer (ACT) therapies in Switzerland. This form of immunotherapy requires the development of tools for the selection of patient’s immune cells that are most specific to the mutational landscape of their tumour. First, the chapter details how experts in this setting diverge on ideas, tools and heuristics to explain cancer. These positionings are akin or relate to the opposition between the so-called ‘somatic mutation/clonal’ theories of tumorigenesis and the holistic approaches to cancer known as ‘tissue organization field theory’. Second, the chapter details practical ways these diverging explanations are brought together. In fact, a specific experimental and organisational work enables a minima the functioning of a shared research program of precision immuno-oncology. No doubt, practitioners leverage the different explanatory frameworks we examine as oppositional elements structuring distinct interpretations of and experimentations on cancer. Yet, our study suggests that the gap between these alternative explanations might be far narrower than postulated by those who consider them incommensurable theories of cancer. Issues of integration and compatibility are seldom discussed by the concerned actors in daily collaboration, nor they prevent common experimentation. This socio-epistemic process offers us the opportunity to conclude by elaborating on the insights social science methods provide to philosophical questions of alleged incommensurability between theoretical presuppositions in cancer research.