In male massive weight loss patients, there may be underlying musculoskeletal deformity with barrel chest. Glandular breast tissue may be present. Skin is excessive vertically and horizontally, with a visible inframammary fold (IMF), and skin excess may extend posteriorly to the upper back. Standard position of the NAC is just lateral to the pectoralis muscle, 20 cm from the sternal notch and 10 cm from midline. With gynecomastia, nipple-areolar position is lower, oftentimes beneath the inframammary fold.

Most male neonates have some amount of palpable breast tissue. The next chronological peak for gynecomastia occurs during puberty, with the last peak occurring in men between 50 and 69 years of age.

Physiological gynecomastia in pubertal male teens is benign and self-limited; on the other hand, several conditions and drugs may induce proliferation of male breast tissue. Most cases result from estrogen excess and/or androgen deficiency as a consequence of different endocrine disorders.

Thyroid and testicular disease may cause gynecomastia.

Biochemical evaluation should be performed once physiological or iatrogenic gynecomastia has been ruled out. Nonendocrine illnesses, including liver failure and chronic kidney disease, are other cause of gynecomastia that should be considered.

Medications associated with the onset of gynecomastia are spironolactone, cimetidine, ketoconazole, hGH, estrogens, hCG, antiandrogens, GnRH analogs, and 5-α reductase inhibitors.

History should be queried regarding potential causes of gynecomastia that may be reversible, such as use of medications or marijuana. Medical history including hyperthyroidism or testicular disease should be checked, in addition to family history of breast cancer. Symptoms such as pain and nipple discharge should be checked.

Physical examination should emphasize on the chest as well as other body regions elicited on medical history. Examination of the chest wall should focus on symmetry, presence of breast tissue, skin quality, underlying thoracic/skeletal deformities, and any masses on palpation. Testicular physical examination is warranted.

Examination of the massive weight loss patient may also assess other body regions that may be directly or secondarily addressed at the time of gynecomastia correction.

Mammogram should be considered in a male with breast asymmetry, palpable mass, or family history of breast cancer.⁴ If there are any suspicious findings on mammogram, ultrasound and MRI studies may follow, with PET/CT if concerns are present for metastatic breast cancer.