Related Experiment Video
Updated: May 22, 2026

Changes in Mammary Gland Morphology and Breast Cancer Risk in Rats
Published on: October 16, 2010
Gynecomastia
1University of Kansas School of Medicine, Wichita, KS 67214, USA. gdickson@kumc.edu
Abstract:
Gynecomastia is defined as benign proliferation of glandular breast tissue in men. Physiologic gynecomastia is common in newborns, adolescents, and older men. It is self-limited, but can be treated to minimize emotional distress and physical discomfort. Nonphysiologic gynecomastia may be caused by chronic conditions (e.g., cirrhosis, hypogonadism, renal insufficiency); use of medications, supplements, or illicit drugs; and, rarely, tumors. Discontinuing use of contributing medications and treating underlying disease are the mainstay of treatment. Medications, such as estrogen receptor modulators, and surgery have a role in treating gynecomastia in select patients. Treatment should be pursued early and should be directed by the patient.
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