Technique: skin thickness was measured at the 6 o'clock position in both breasts using ultrasonography
Measurements:
(1) skin thickness in mm on the side with breast cancer
(2) skin thickness in mm on the opposite side
ratio of skin thicknesses =
= (skin thickness in mm on the affected side) / (skin thickness in mm on the unaffected side)
Criteria for lymphedema:
(1) skin thickness on the affected side >= 3.2 mm
(2) ratio of skin thicknesses >= 1.32
Performance:
• The sensitivity of the skin thickness was 78%, the specificity 92% and area under the ROC curve 0.82.
• The sensitivity of the ratios of skin thickness was 81%, the specificity 82% and area under the ROC curve 0.86.
Limitation:
• The ratio may not work if the woman has bilateral breast disease.
• The measurements may not work in a woman with scleroderma or other infiltrative skin disease.