Several reports have showed an increased risk of secondary malignancies after bone marrow transplantation (BMT), especially after total body irradiation (TBI). We report on a 39-year-old female who underwent BMT with a matched unrelated donor because of acute myeloid leukemia in second complete remission. Previously, the patient received chemotherapy for induction, consolidation, maintenance and reinduction after diagnosis of relapse. Conditioning regimen consisted of cyclophosphamide and TBI. MTX and CSA was administered for GvHD prophylaxis. Engraftment was confirmed on day 28. Within 6 months following BMT, no complication occurred. Continuous complete remission was demonstrated by repeated bone marrow smears. On day 300 the patient complained of chest pain and dyspnea. X-ray and CT-scan showed thickening of the pleura and pleural effusion. A pleuracarcinosis was diagnosed by cytologic examination of a pleural aspirate. By an open thoracotomy a disseminated inoperable disease became apparent. Diagnosis of an adenocarcinoma was confirmed by histologic examination. The patient died 2 months later due to disseminated tumour in complete remission of AML. Solid tumours are rare as secondary malignancies after BMT. Usually the neoplasmas are late events occurring more than 10 years after BMT. In this case predisposing factors such as genetic disposition, long-term smoking, intensive pretransplant chemotherapy, TBI and immunosuppression may have lead to the early secondary malignancy.