She is a member of several pathology and oncology societies, including the European Society for Medical Oncology (ESMO), the American Society of Clinical Oncology (ASCO), the French Society of Pathology, Senologia, and the Study Group for Prognostic and Predictive Factors for Immunohistochemistry (GEFPICS), with her main areas of interest being female cancers. Professor Penault-Llorca has conducted various biomarkers-based research studies in breast, colorectal, gastric, and lung cancer in relation to response to targeted therapies and immunotherapies. She also acts as a coordinating pathologist for various oncology trials. Professor Penault-Llorca has written more than 400 peer-reviewed publications and several books on female cancers and pathologic testing methods and issues.