Gynecomastia, also known as male breast enlargement, is a male breast disease frequently encountered in plastic surgery, and its incidence accounts for about 60%-80% of male breast diseases. It usually manifests as painless progressive breast enlargement or areola deep masses, sometimes with pain or tenderness, and occasionally with milk-like discharge, which may have serious psychological and social effects on patients. The development of male breast development is regulated by estrogen, progesterone, growth hormone, prolactin and other hormones. Male breast enlargement is mainly caused by the relative or absolute increase of effective estrogen in the body, and estrogen and its related hormones in the body environment interact with local breast hormone receptors to induce male breast development. The diagnosis of physiological gynecomastia can be divided into two categories: physiological gynecomastia is mostly of pharmacogenetic origin, and a few are seen in tumors and various endocrine diseases. The diagnosis of gynecomastia is usually based on the appearance and the patient’s complaints. The diagnosis of gynecomastia is generally clear, and the use of ultrasound and radiography can help in the differential diagnosis. The typical two-dimensional image shows a disc-shaped or sideways fan-shaped or shuttle-shaped hypoechoic area centered on the nipple, clearly demarcated from the surrounding tissues, with uneven internal echogenicity and a convergence of strong tubular echogenicity toward the nipple. Mammograms of gynecomastia show increased density due to the development of the glandular tissue, and the contrast with the surrounding tissue is very clear, which can be fibrous, large nodular, patchy and small nodular. Treatment principles for gynecomastia The treatment of gynecomastia is mostly for cosmetic purposes, and only a few are for the prevention of cancer, as the cancer rate is very low. The treatment methods are etiological treatment, drug treatment and surgical treatment. Etiological treatment and drug treatment are mainly used for pathological gynecomastia, and the treatment lies in stopping the use of drugs and treating the original disease. However, if the developed breast does not shrink after medical observation or medication, and the patient requests plastic surgery for cosmetic purposes, surgical treatment can be considered from the plastic surgery perspective, while for physiological gynecomastia, surgical treatment is the main choice. Surgical options for gynecomastia Gynecomastia can be divided into 3 categories according to the different signs, and different treatment methods are proposed according to the different degrees of breast development. The surgical procedures for gynecomastia can also be broadly divided into three categories: the first category is the sharp excision method, the second category is the liposuction method, and the third category is the liposuction plus sharp excision method. The sharp excision method can be divided into the lower areolar margin incision, double circumferential incision around the areola, and inframammary fold incision depending on the incision site. Most patients were satisfied with the appearance of the three methods after treatment, but in terms of scar formation, the scar was most pronounced in patients who underwent glandular excision using the periareolar double-ring incision, which may be related to the increased tension of the wound caused by the removal of skin through the double-ring method, resulting in scar growth at a later stage. In terms of nipple areola sensation, again, the most pronounced hyperalgesia was seen in the double ring group, followed by the inferior crease group, with the least hyperalgesia in the inferior areola hemi-annuloplasty incision. This is related to the ease of injury to the sensory nerves that innervate the areola nipples with circumferential injury. In recent years, there has been an increase in the number of patients with gynecomastia, and patients are becoming more and more demanding in terms of postoperative aesthetics, with no visible signs of surgery being the best realm. Except for the feminization of the male breast due to simple obesity, where minimal scarring can be achieved by simple liposuction or ultrasound-assisted liposuction, most require removal through a certain incision, and the use of a semi-annular incision at the lower edge of the areola is undoubtedly the best. Because the true glandular tissue will behave very tough, simple liposuction cannot remove the true glandular tissue.