Thanks for your question.
Such a lump on the finger is likely to be a ganglion cyst which forms around the joints or tendons. If this is a ganglion cyst as confirmed by your doctor after examination and if it is not causing any pain or discomfort, it can be left and may disappear without treatment. Other cause for the lump may be a wart, or due to osteoarthritis and other arthritis-related conditions. An examination by your doctor and imaging studies such as an x-ray may be required to find out the exact cause. Sometimes biopsy may also be done.
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How is the consistency of the swelling? Is it firm or soft?
In that case it is nothing to worry about. It could be a soft tissue swelling such as lipoma. Therefore please do not worry about this and just make sure that your doctor examines this whenever you visit him next.
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