The purpose of this post-authorisation medical device study is to obtain real life data on the use of Tumor Treating Fields (TTFields) in patients with pleural mesothelioma in routine clinical care. Patients with pleural mesothelioma and clinical indication for TTFields treatment will be enrolled in the study after signing Informed consent to use their data and process it centrally for research purposes. The clinical indication for TTFields is one of the inclusion criteria and is defined prior to inclusion by the treating physician.