This case illustrates early CT findings of mesothelioma involving the right hemithorax and characterized by micronodules covering the hemidiaphragm and slightly thickening the fissures. Given the pleural effusion was recurrent, the patient underwent a pleural tab after the radiograph and cytology showed some malignant cells, a further pleural biopsy confirmed mesothelioma. Note that there are no calcified pleural plaques.