Table 2.

Distribution of TDLU and MD measures among women with benign breast disease, stratified by menopausal status

OverallPremenopausalPostmenopausal
MedianRangeCorrelation with age, rCorrelation with BMI, rMedianRangeCorrelation with age, rCorrelation with BMI, rMedianRangeCorrelation with age, rCorrelation with BMI, r
TDLU measures
 TDLU count/100 mm210.00–199.2–0.25a−0.29a16.00–199.2−0.14b−0.33a5.50–172.4−0.30a−0.20b
 Median TDLU span, μ25878–809−0.34a−0.0728478–809−0.16b−0.0522483–5680.02−0.02
 Median acini count per TDLU11.01–68−0.36a−0.1013.01–68−0.13−0.038.02–33.5−0.03−0.11
MD measures
 Area measures
  Percent dense area (%)25.90–88.9−0.27a−0.53a32.80–88.9−0.01−0.47a16.30–82.2−0.14−0.59a
  Absolute dense area (cm2)29.90–139.1−0.14b−0.15b35.90–139.10.05−0.0224.70–130.1−0.11−0.32a
  Nondense area (cm2)95.711.6–441.20.28a0.71a79.511.6–441.20.070.71a132.014.9–385.50.090.71a
 Volume measures
  Percent FGV (%)35.10.6–99.3−0.30a−0.61a40.90.6–98.8−0.11−0.60a29.41.5–99.3−0.14−0.62a
  Absolute FGV (cm3)186.26.7–683.5−0.070.29a193.66.7–683.5−0.040.36a173.631–637.8−0.020.21b
  Nondense volume (cm3)345.61.6–21260.24a0.73a282.13.5–21260.080.74a458.81.6–19770.080.71a
 Perilesional volume measures
  Percent perilesional FGV (%)40.20–100−0.31a−0.51a48.20–100−0.14b−0.51a31.70–100−0.06−0.47a
  Absolute perilesional FGV (cm3)6.00–91.5−0.26a−0.11b7.50–86.6−0.23a0.014.30–91.50.004−0.24b
  Nondense perilesional volume (cm3)6.80–137.30.050.36a6.30–126.1−0.070.43a7.80–137.30.130.21b

NOTE: Correlations between MD and TDLU measures (continuous) with age and BMI were assessed by Spearman partial rank-order correlation (r); a, P < 0.001; b, P < 0.05.

We computed the median acini count and median TDLU span for each biopsy with TDLUs observed (n = 194 and n = 101 biopsy targets among pre- and postmenopausal women, respectively).

Abbreviations: BMI, body mass index; FGV, fibroglandular volume; MD, mammographic density; TDLU, terminal duct lobular unit.