[A case of solitary splenic metastasis following operation for pulmonary pleomorphic carcinoma: detected at an early stage by FDG-PET].

A 58-year-old man was admitted our hospital. Chest computed tomography (CT) showed a nodular opacity in the left upper lobe and a swollen lymph node in the left hilar region. 18-fluorodeoxyglucose positron emission tomography (FDG-PET) showed abnormal uptakes in the same field. Since thoracoscopic lung biopsy revealed that the tumor was poorly differentiated adenocarcinoma, a left upper lobectomy and lymph node dissection were performed. Histological findings showed numerous spindle cells, thus it was diagnosed as pleomorphic carcinoma, pT2N1M0. After three months, a FDG-PET was performed, which detected a tiny lesion in the spleen. However an abdominal CT scan and ultrasonography (US) performed in the same period showed no abnormal findings. After about 2 months, a solitary low density area (5.0 cm) was seen in the spleen on an abdominal CT scan. We performed splenectomy under a diagnosis of a solitary splenic metastasis of the lung cancer. Pathological confirmation was obtained. Our findings demonstrated that whole-body scanning by FDG-PET was able to detect a rare postoperative splenic recurrence earlier than CT or US scan.