Cross-Sectional Areas of Calf Soft Tissue Measured with MRI as a New Method for Staging Gynecologic Oncology-Related Extremity Lymphedema

Objectives: To determine whether the cross-sectional area (CSA) of the soft tissue of the calf measured with magnetic resonance imaging (MRI) could stage unilateral lower extremity lymphedema (LEL) secondary to gynecological cancer treatments. Materials and Methods: One hundred and twenty females with unilateral LEL and Thirty-two without LEL after gynecological cancer treatments underwent calf MRI and water displacement. Total soft tissue CSA (T), muscle CSA (M) and subcutaneous tissue CSA (S) of affected calf, and difference of T (DT), M (DM) and S (DS) between calves were obtained on MRI at mid-calf level. Volume of affected calf and difference of volume (DV) between calves were obtained by water displacement. Statistical analysis was performed to determine feasibility of MRI measurements for accessing LEL. Results: There were close correlations between volume and T or S of affected calf, and between DV and DT or DS of calves. The correlations of stages of LEL with T and S of affected calf as well as DT and DS were stronger than with the volume of affected calf and DV (all p < 0.01). Multivariate analysis showed more significant differences between LEL stages in T and S than in volume of affected calf, and in DS than in DV (all p < 0.05). No difference was found between stage 0 and 1 in volume of affected calf and in DV. For staging LEL, DS showed the most profound discrimination ability among all measurable parameters. Conclusions: DS of calves could be the most reliable parameter recommended for staging unilateral LEL.