TY - JOUR T1 - A case of a Β3 thymoma arising from a “giant” mediastinal thymolipoma JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2015.PA4320 VL - 46 IS - suppl 59 SP - PA4320 AU - Violaine Yvorel AU - Fabien Forest AU - Georgia Karpathiou AU - Marie-Laure Stachowicz AU - Olivier Tiffet AU - Abdulrazzaq Sulaiman AU - Eric Parietti AU - Michel Péoc'h Y1 - 2015/09/01 UR - http://erj.ersjournals.com/content/46/suppl_59/PA4320.abstract N2 - Introduction: Thymolipoma is a rare benign neoplasm of the anterior mediastinum accounting for 2%-9% of thymic tumors. It mainly consists of adipose tissue comporting foci of thymic tissue. Neoplastic transformation of the epithelial component is extremely rare with four cases of thymoma and a case of thymic carcinoid previously reported.Aim: To report a case of thymolipoma associated with B3 thymoma.Case presentation: A 59 year-old woman treated for asthma presented with dyspnea. No mysthenia gravis was present. Imaging revealed a huge mediastinal tumor of fat density compressing the right lung. Surgical resection revealed a 2.8 kg and 39 cm tumor of mainly lipomatous aspect comporting a stellar solid focus of 3 cm. Microscopically, the tumor was a thymolipoma, with a focus (3 cm) of a B3 thymoma. No complementary treatment was applied and the patient is disease-free, two months after operation.Conclusion: This is the first case of a B3 thymoma arising inside a giant thymolipoma. Diagnosis of thymolipoma should be suspected in a fat-density tumor of the anterior mediastinum. Malignant transformation despite rare is possible and resection is mandatory. ER -