Bilateral Pleural Mesothelioma In Situ and Peritoneal Mesothelioma In Situ Associated With BAP1 Germline Mutation: A Case Report

Mesothelioma in situ is a recently described precursor to invasive mesothelioma. Thus far, all cases in the literature have involved one pleural cavity or the peritoneal cavity. We describe a patient with biopsy-proven mesothelioma in situ involving both pleural cavities and the peritoneal cavity. Genetic analysis results revealed that the patient had a BAP1 germline mutation. This is the first report of mesothelioma in situ involving multiple body cavities and raises a question of whether such patients will all have BAP1 germline mutations.(c) 2022 The Authors. Published by Elsevier Inc. on behalf of the International Association for the Study of Lung Cancer. This is an open access article under the CC BY-NC-ND li-cense (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).