Abstract
A previously healthy 71-year-old woman presented at our hospital in July 2012 with a mass on the left side of her back ; she also experienced excruciating pain while exercising. The chest magnetic resonance imaging revealed a high-intensity hourglass-shaped mass, measuring 45 × 35 × 35 mm in size, in the T1 and T2 waves, penetrating the left 8th intercostal muscle. We performed a complete resection of the tumor and partial resection of the 8th and 9th ribs using thoracoscopy ; the chest wall was reconstructed using an expanded polytetrafluoroethylene sheet. The mass was pathologically diagnosed as an infiltrating intramuscular lipoma. She was followed-up for 6 months ; there was no recurrence.
Lipomas are common benign tumors. However, intrathoracic lipomas are rare, and hourglass transmural lipomas are even rarer, with only seven cases reported in Japan. The tumor cannot be diagnosed pathologically until the thoracic wall tumor is resected. Therefore, during the operation, it was unclear if the tumor was a benign lipoma or a malignant liposarcoma.
Although thoracoscopic surgery is a common procedure, thoracoscopically resecting a tumor wedged between ribs is difficult. Hence, in hourglass transmural lipoma cases, tumor resection and partial resection of the ribs is an effective surgical procedure.
