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1.The bony lesion in the iliac bone on the repeated CT and
MRI scans in a known case of Carcinoma in-situ primary suspicion will be secondaries.
2.You may need to get a CT with contrast will give more information and confirmation of metastasis.
3.Since its second lesion, A compete screening of brain and skull x-ray to see any further lesions.
4.If no other lesions then bone
biopsy to evaluate the nature of the cells involved.
5.Suggest a followup with both the lesions and clinical correlation.
Good luck.
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