MediAI

  A Case-Based Review of Imaging Findings, Differential Diagnosis, Clinical Consequences, and AI-Assisted Interpretation A focal liver lesion with increased prostate-specific membrane antigen (PSMA) uptake in a patient with prostate cancer raises concern for metastatic disease. However, PSMA uptake is not synonymous with malignancy. Hepatic hemangiomas, benign vascular lesions, can demonstrate increased uptake and mimic liver metastases on PSMA positron emission tomography/computed tomography (PET/CT). The key diagnostic principle is to correlate tracer uptake with CT morphology, contrast-enhancement patterns, clinical risk, and, when necessary, liver magnetic resonance imaging (MRI). In this case, two PSMA-avid liver lesions in a man in his 60s undergoing prostate cancer staging were ultimately diagnosed as benign hemangiomas in an external pathology report. Recognizing this pitfall can prevent incorrect upstaging and unnecessary investigations or treatment. Why This Case Matters ...

  Clinical Hook An 86-year-old man had already endured years of treatment for advanced prostate cancer. His prostate-specific antigen (PSA) level began to rise again despite ongoing luteinizing hormone-releasing hormone (LHRH) agonist therapy. Surprisingly, the bone scan showed no evidence of metastatic disease. For many clinicians, a normal bone scan might appear reassuring. Yet the patient's biochemical profile suggested otherwise. Was this simply biochemical recurrence, or was metastatic disease hiding beyond the limits of conventional imaging? A subsequent 18F-FDHT PET/CT answered that question decisively. The examination revealed extensive lymph node metastases above and below the diaphragm, multiple skeletal metastases, and high androgen receptor (AR) expression throughout the metastatic lesions. Based on these findings, the patient's treatment strategy changed from continued hormonal suppression alone to consideration of androgen receptor antagonist therapy. This case ...