I disagree with the above expert
First of all it appears that you indicate that this mass is not in the breast...is that correct?
but rather on the rib cage.
Since you have silicone implants, the mass could be a siliconoma, which is where silicone migrates and forms a mass.
This is a possibility here.
A cyst would not be so elongated typically.
If you have a large concern, and MRI would be helpful in definitely ruling out breast cancer if this were in the breast.
Fine needle aspiration could define what this is...cyst, lipoma, or siliconoma.
Let me know if you have further questions
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