<p> Supplementary online material: Distribution of fibrocystic changes in reduction mammaplasty specimens</p><p>All Patients with mammary Patients with breast Patients Patients Patients with specimen Patients with specimen patients hypertrophy (no breast asymmetry (positive breast ≤50 years >50 years weight ≤500g weight >500g cancer history) cancer history) n=311 n=79 n=233 n=157 n = 390 n=355 n=35 Fibrolipomatosis, n (%) 38 (9.7) 36 (10.1) 2 (5.7) 33 (10.6) 5 (6.3) 18 (5.7) 20 (9.1)</p><p>Fibrosis, n (%) 201 (51.5) 187 (52.7) 14 (40.0) 171 (55.0) 30 (38.0)** 117 (37.1) 84 (38.4)</p><p>Cysts, n (%) 3 (0.8) 2 (0.6) 1 (2.9) 1 (0.3) 2 (2.5) 2 (0.6) 1 (0.5)</p><p>Adenosis, n (%) 15 (3.8) 15 (4.2) 0 10 (3.2) 5 (6.3) 9 (2.9) 6 (2.7)</p><p>Sclerosing adenosis ‡ 8 (2.1) 8 (2.3) 0 6 (1.9) 2 (2.5) 4 (1.3) 4 (1.8)</p><p>Metaplasia, n (%) 22 (5.6) 17 (4.8) 5 (14.3) 13 (4.2) 9 (11.4)* 15 (4.8) 7 (4.5)</p><p>Epithelial hyperplasia, n (%) 37 (9.5) 33 (9.3) 4 (11.4) 29 (9.3) 8 (10.1) 28 (8.9) 9 (4.1)*</p><p>Moderate ‡ 2 (0.5) 1 (0.3) 1 (2.9) 2 (0.6) 0 2 (0.6) 0</p><p>Atypical ‡ 0 0 0 0 0 0 0</p><p>Columnar cell lesions, n (%) 0 0 0 0 0 0 0</p><p>Radial scar and complex 0 0 0 0 0 0 0 sclerosing lesions, n (%)</p><p>Intraductal papilloma and 5 (1.3) 5 (1.4) 0 4 (1.3) 1 (1.3) 4 (1.3) 1 (0.5) papillomatosis, n (%) ‡</p><p>Unspecified fibrocystic 107 (27.4) 94 (26.5) 13 (37.1) 77 (24.8) 30 (38.0) 78 (24.5) 29 (13.2)** changes</p><p>*, p <0.05, **, p <0.01 between 2 consecutive criteria. ‡ Benign breast lesions associated to increased risk of breast cancer according to College of American Pathologist (Fitzgibbons et al, 1998) </p>