Gynecomastia is a swelling of the breast tissue in boys or men, caused by an imbalance of the hormones estrogen and
testosterone. Gynecomastia can affect one or both breasts, sometimes unevenly. signs and symptoms usually include swollen breast gland tissue and breast tenderness.
In most cases if the causative factor is removed it will regress over time, there are multiple medical options for treatment as well other than surgery.