[Lipoma of the diaphragm; report of a case]

A 50-year-old man was referred to our hospital with an abnormal shadow on chest roentgenogram taken on a health examination in September, 1999. His past history was an operation for scoliosis at the age of 39 years. His family history was unremarkable. Chest roentgenogram showed a smooth rounded bulging nodule in continuity with the left diaphragm. Chest computed tomography (CT) revealed a well-defined and homogeneous nodular lesion with a low attenuation value of -100 Hounsfield unit, corresponding with a fat density, on the base of the left hemithorax. For making diagnosis and treatment, videothoracoscopic surgery was performed in January, 2000. The tumor was removed with combined resection of diaphragm, using stapling device, because the lesion partially adhered to the diaphragm. The postoperative course was uneventful. The pathological diagnosis was lipoma About 2 years later. he was again found to have a similar abnormal shadow on a routine chest roentgenogram in August, 2003. Chest CT showed a nodular lesion involving a previous operative staple line on the base of the left hemithorax. We considered this lesion to be a locally recurrent tumor and performed surgical resection of the lesion with a wide margin of normal diaphragm and partial retroperitoneal fat tissue. The pathological diagnosis of the resected specimen was again lipoma. Since then, he has been in good health without recurrence for about 4 years.