Applying comprehensive histologic assessment and genetic testing to synchronous multifocal lung adenocarcinomas and further survival analysis

To the Editor:The differentiation of multiple primary lung adenocarcinomas (MPLAs) from metastases is important to allow for proper clinical management and prognostic prediction.The current revised diagnostic criteria for MPLAs proposed by the American College of Chest Physicians (ACCP) have been commonly applied since 2003.[1] However, it remains technically challenging to determine whether 2 or more lung adenocarcinomas from the same patient are homologous.Various approaches and algorithms including gene mutation analysis addressing this problem have been described.[2,3] Here, we present a cohort of 45 patients with synchronous multifocal lung adenocarcinomas.