Conversation: The conversation between human and AI assistant.
[|Human|] I had a bone scan to check to see if my prostate cancer had spread, but it showed negative. When I had an MRI scan however, there was dark patches showing on my skeleton in many places. I had to have a bone biopsy.  Have you any ideas of what it could be. I am a man of 64.
[|AI|]  Thanks for your question on Chat Doctor. I can understand your concern. In my opinion, possibility of metastatic bone lesions is high in your case. Prostate cancer is known to have metastasis in bones. It gives osteoblastic secondaries. PET scan can pick up lesions only when they are more than 2-3 CMS. Small metastatic lesions can not be picked up by PET scan and hence you are having negative scan. In this case MRI is more sensitive because it can pick up lesions with size less than 1 cm. But biopsy and histopathological confirmation is needed for the diagnosis of bone metastases. So my suspicion is metastatic bone lesions and hence you need to get done biopsy for confirmation. Hope I have solved your. Wish you good health. Thanks.