The leading cause of cancer-related death worldwide is lung cancer. While hematogenous spread from primary lung cancer to multiple other organs is frequently reported, metastases of malignant tumors to diaphragm and to spleen are rare. Nowadays, Positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) has evolved in such a way that it has become a useful imaging modality in the assessment of various cancers, particularly for tumor staging and post treatment monitoring. It is able to provide metabolic information. In this case, we present an interesting integrated PET/CT imaging in a lung cancer patient with rare, diaphragm and splenic metastases. So, PET/CT could very well demonstrated rare and unexpected metastatic cancer and provided more accurate staging in a lung cancer patient.