Abstract: A 71-year-old man presented with a progressive right knee pain which persisted for 6 months and was not relieved by pain medications. He had a history of lung squamous carcinoma 1 year ago. X-ray and magnetic resonance imaging (MRI) revealed hyperostosis, degenerative changes, and occupancy lesions of the right patella. The patient underwent 99mTc methylene diphosphonate (99mTc-MDP) bone scan and single photon emission tomography/computed tomography (SPECT/CT), which showed abnormal metabolism of the right patella with bone destruction and soft tissue swelling. Finally, patellectomy was taken and pathology confirmed patella metastasis from lung squamous carcinoma.