Hello,
Thanks for posting your query.
The condition your son is having is called Gynaecomastia .Gynecomastia is usually secondary to the normal hormonal imbalances between testosterone and estrogen that commonly occurs during puberty (pubertal gynecomastia) and it may affect up to 40% of adolescent boys during puberty,
It is physiological or normal phase of development during this teenage .
It should resolve once he completes his pubertal stages and attains adult maturity which may take few months to years.
Yes , your doctor has rightly advised that there are surgical procedures to remove fat from the male breast in cases of abnormal Gynaecomastia .
However as of now I do not think your son needs any such procedure.
Sometimes, treatment may be required if he has very large breast development, if it is not regressing, or if it is causing a lot of stress or anxiety in your child.
Male breast growth that has not stopped by three years, may not go away. In these situations, an evaluation by an experienced Plastic Surgeon can be helpful, either to provide further reassurance or to surgically remove the breast tissue. Surgical sculpture in skilled hands can be a simple solution for this problem.

So please reassure your son and have patience as this is a normal phase of development which will self resolve with time.
Hope I have answered your query.
Kindly accept my answer if you have no further queries.
Regards

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