Welcome to HealthcareMagic. This type of breast swelling of enlargement in males is called gynecmastia. There are various causes of gynecomastia
. One of the most common cause is obesity. Please check it out. If he is obese then he needs to cut down on his fat by regular exercise.
Another important cause is an imbalance between the male and female sex hormones
like in Hypogonadotropic Hypogonadism
and pituitary disorders. So for this he needs to be seen by an endocrinologist
as further tests are required.
Hope it helps you. Regards.