ESPE Abstracts

Background: Pubertal gynaecomastia (PG) is considered a clinical sign of an oestrogen–androgen imbalance at the breast tissue level although little evidence exists. PG occurs in 40–60% of adolescent Caucasian boys, and in most cases however, no underlying endocrinopathy can be identified. Very few longitudinal studies on PG exist.

Objective and method: As a part of the longitudinal COPENHAGEN Puberty Study we followed 110 healthy Danish boys (aged 5.8–16.4 years) in a prospective cohort over 7 years with semi-annual examinations including blood samples (FSH, LH, testosterone, estradiol, SHBG, and IGF1), to assess the development of pubertal gynaecomastia by palpation. The boys each had from two to 14 examinations. Anthropometry and pubertal stages (PH1–6 and G1–5) were evaluated, testicular volume was determined using Prader’s orchidometer, and the presence of gynaecomastia was assessed.

Results: A total of 949 examinations were carried out and PG was present at 107 of the examinations. 50 of the boys (45%) of the boys developed gynaecomastia during the 7 years period. Median age at first examination with PG was 13.3 years (ranging from 10.8 to 15.3 years), and the median genital stage was G3 (ranging G2–G5). The average testicular volume at presentation was 12 ml (ranging from 4 to 25 ml). In addition two boys G1 but pubic hair stage PH2 presented with gynaecomastia at age 12.0 and 12.5 years, respectively. Twelve of the boys had intermittent gynaecomastia with one or more intermediate examinations without the presence of gynaecomastia follow by examinations with palpable gynaecomastia. To our knowledge this is the first report of a ‘coming and going’ breast phenomenon in adolescent boys, which may result from difficulties in palpation of glandular breast tissue, especially in obese boys, but could also reflect a biological phenomenon due to fluctuating sex steroid levels.