Gynecomastia is seen in two-thirds of adolescent boys during mid to late puberty. It is a normal finding during development. Reassurance is all that is needed.
Enlargement of the breasts can be a normal finding in puberty in males. It results from increased testicular production of estrogen over testosterone and peripheral conversion of prohormones to estrogen. Gynecomastia may be unilateral, bilateral, or painful. Management includes reassurance and watchful waiting since these symptoms usually resolve in less than two years.
Blondell et al. discuss disorders of puberty. Puberty naturally begins between 8 and 14 years in girls and between 9 and 14 years in boys. Pubic hair distribution is used to stage puberty, along with breast size and contour in girls and testicular volume in boys.
Dickson discusses gynecomastia. The syndrome is defined as bengin proliferation of glandular breast tissue in men. Physiologic gynecomastia may occur in newborns, adolescents, and older men. It is self-limited but may be treated to minimize emotional distress. Nonphysiologic gynecomastica may be caused by chronic conditions such as cirrhosis, hypogonadism, renal insuffiency, and medications, supplements or illicit drugs. Estrogen receptor modulators and surgery have a role in treatment in select patients.
Sasco et al. discuss male breast cancer. Male breast cancer is a rare tumor and only 1% of breast tumors are in men. There is a positive correlation between males who develop prostate cancer and those who develop breast cancer.
Figure A depicts the classic appearance of adolescent gynecomastia.
Answers 1 and 2: Since gynecomastia in adolescence may be seen normally in development no lab tests are required.
Answers 3 and 4: Mammogram and core needle biopsy are sometimes indicated in the workup of a breast mass in an individual with suspected breast cancer but would not be necessary in this case.
Blondell RD, Foster MB, Dave KC. Disorders of puberty. Am Fam Physician. 1999 Jul;60(1):209-18, 223-4.
PMID:10414639 (Link to Abstract)
Dickson G. Gynecomastia. Am Fam Physician. 2012 Apr 1;85(7):716-22.
PMID:22534349 (Link to Abstract)
Sasco AJ, Lowenfels AB, Pasker-de Jong P. Review article: epidemiology of male breast cancer. A meta-analysis of published case-control studies and discussion of selected aetiological factors. Int J Cancer. 1993 Feb 20;53(4):538-49.
PMID:8436428 (Link to Abstract)