BackgroundHow can research remain as faithful as possible to the psychoanalytical approach, which proceeds by case study, and at the same time meet the current requirements for scientific validation and publication in clinical psychology? Especially if the project is part of an interdisciplinary context, aiming to bring psychoanalysis – which promotes qualitative analysis – into dialogue with epistemological frameworks that use very different methods such as, for example, quantitative and hypothetical-deductive medicine. Although psychoanalysis was conceived, from its origins, as both a theory of the human psyche and as a therapeutic method seeking to validate its foundations – the hypothesis of the unconscious, analysis and interpretation of the transference on the analyst –, its endogenous validation criteria remain insufficient, from the point of view of research in the human and social sciences where the psychologist-researcher situates her/himself. Even if a translation of the results is possible, a methodology that guarantees objective results accepted by a larger scientific community is required. Our study, wishing to better understand the psychological effects of cancer in adolescence and early adulthood on romantic life and sexuality, had to consider these epistemological concerns. Conceived from its origin in a dual culture – that of medical care and clinical psychology with an analytical orientation –, it led us to use the qualitative methodology of Grounded theory (GT). Our paper aims to show that the use of GT ensures scientific rigor while maintaining the essentials of the psychoanalytical method and process – applied, in this context, to the collection and analysis of data, and to the way of producing results. MethodologyAlthough they come from sociology, we will show that many of the core operators of GT are very close to psychoanalytical ones. For example, inductive and iterative dimensions or the necessary a-theoretical approach of the researcher offer particularly congruent points of contact with the psychoanalytical process, which we will illustrate with concrete examples from our study. ResultsThe inductive, reflexive, and iterative properties of GT are very close to the central operators of the psychoanalytical process while respecting an accepted scientific approach in the social sciences. Promoting co-constructive results and articulating individual and populational scales, they respect both the psychodynamic subjectivity of the participants and the conditions for targeting a scientific approach more generally used in the social sciences. Moreover, using GT in psychoanalytical research fosters translational research and an immediate transfer of scientific knowledge to participants in the field. This is another point of similarity with the psychoanalytical method in which the process itself can be considered as a result. ConclusionGT offers the psychologist-researcher with a psychoanalytical orientation a particularly relevant methodological tool to satisfy many validation conditions of other scientific communities, while respecting his or her epistemological and clinical reference. It is therefore a valuable methodological operator for interdisciplinary research in psychoanalytical psychology.