[Intrathoracic giant tumor accompanied by hypoglycemia]

Some non-islet tumors can induce hypoglycemia. We report a case of an intrathoracic giant tumor accompanied by hypoglycemia. The patient was a 53-year-old woman who was found to have hypoglycemia. Chest X-ray film showed a giant tumor in the left hemithorax and rightward shift to the mediastinum. CT and MRI revealed that the tumor's border was clear. The tumor was removed by sternotomy with third and seventh inter-costal incisions. The tumor was lobulated but its border was clear. It seemed to have grown from the posterolateral thoracic wall. After the tumor was removed, re-expansion pulmonary edema occurred but was relieved by diuretics and respiratory management. Histologic findings indicated that it was probably a thymoma or a localised mesothelioma, but it could not be identified even with special stains. Solitary fibrous mesotheliomas are sometimes complicated by hypoglycemia, and some of them produce insulin-like growth factor (IGF). In this case, the pre-operative level of immuno-reactive insulin was low, so the tumor may have produced IGF.